Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Stanford Institute for Materials and Energy Sciences (SIMES) Field Budget Request for FY2016 FWP Page Time‐Resolved Soft X-ray Materials Science at the LCLS & ALS 2 Diamondoid Science and Applications 11 Electronic and Magnetic Structure of Quantum Materials 14 Correlated Materials – Synthesis and Physical Properties 20 Spin Physics 26 Clathrin Biotemplating 30 Magnetization & Dynamic 33 Atomic Engineering Oxide Heterostructures: Materials by Design 37 Two-Dimensional Chalcogenide Nanomaterials 40 Joint Center for Energy Storage Research (JCESR) 44 Nanostructured Design of Sulfur Cathodes for High Energy Lithium-Sulfur Batteries 46 Pre-Lithiation of Silicon Anode for High Energy Li Ion Batteries 1 63 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS Date Submitted: 6/18/2015 FWP#: 10017 Time‐Resolved Soft X-ray Materials Science at the LCLS & ALS Principal Investigator(s): T. P. Devereaux, Z.-X. Shen, Z. Hussain, Tony Heinz, A. Lindenberg, D. Reis, and W. Mao Staff Scientists: Wei-Sheng Lee, Yi-De Chuang, Mariano Trigo, Hongchen Jiang Postdoctoral Scholars and Graduate Students: Crystal Bray, Martin Claassen, Jesse Clark, Frank Chen, Simon Gerber, Thomas Henighan, Te Hu, Shigeto Hirai, Chunjing Jia, Mason Jiang, Michael Kozina, Yu Lin, Shenxiu Liu, Ehren Mannebach, Christian Mendl, Clara Nyby, Dylan Rittman, Renee Sher, Michael Shu, Kai Wu, Peter Zalden, Qiaoshi Zeng, Zhao Zhao Overview: This program connects concepts of ultrafast time-domain science with those for momentum- and energydomain x-ray spectroscopy. The FWP consists of the single-investigator small group research (SISGR) program (Devereaux, Lee, Shen, Moritz, Hussain, Chuang) on time-resolved soft x-ray materials science at the Linac Coherent Light Source (LCLS) and the Advanced Light Source (ALS), merged with the recent addition of high pressure studies (Mao), ultrafast activities (Lindenberg, Reis) on non-equilibrium phonon dynamics and phase transitions, nanoscale dynamics and ferroelectric oxide ultrafast processes, and ultrafast optical studies of 2D chalcoganide materials (Heinz). The combined activities bring a synergy to explore how materials behave under extreme conditions, driving lattice and charge conformational changes by applying short pulses, high fields, or high pressures. The purpose of this research is to develop a world-class program on the dynamics of complex materials using the x-ray beamlines available at LCLS to address the grand challenge problems of “emergence”, non-equilibrium dynamics, and to probe model systems for deep insights on materials for energy conversion, transport and efficiency. Theoretical calculations and simulations conducted in parallel with experimental progress will establish a formalism for describing non-equilibrium physics of strongly correlated and related materials and provide additional guidance to experiments. This activity requires the development of novel theoretical and computational tools and as well as the deployment of standard techniques designed to uncover the nature of the many-body state both in and out of equilibrium. We have made substantial progresses on several research fronts to advance our understanding of complex materials through advanced x-ray based techniques coupled with advanced numerical simulations. These include LCLS- and synchrotron based experiments to further the study novel quantum materials and extend knowledge of time-domain based x-ray spectroscopy. In the following, we outline our progress through lists of bullets. Progress in FY2015 LCLS-related activities: We have performed the first pulsed magnetic field experiment at LCLS to study charge density wave (CDW) state in YaBa2Cu3O6.67. With this new experimental setup, we investigated the CDW evolution up to 28 Tesla, significantly higher than previous experiments. Surprisingly, in addition to the CDW already existing at zero field, we observed another CDW correlation emerges at high field and low temperatures. Its field and temperature dependence are consistent with the NMR observations that have been attributed to the CDW state; thus, they likely share the same origin. Furthermore, our results directly reveal that this CDW is three dimensionally ordered with a propagating wave vector different than that of the zero-field CDW. We have directly characterized the photo-induced coherent lattice dynamics in a parent iron-superconductor BaFe2As2 via time-resolved x-ray scattering experiment at the LCLS. Combining with theoretical investigation, we evaluated associated changes in the band structure, Fermi surface, and magnetic properties. This work has been accepted for publishing on Nature Communication. (S. Geber et al., Nature Communications accepted). Recently, we performed a continuation experiment to further investigate the temperature and doping dependence of the photo-induced coherent lattice dynamics in BaFe2As2 and superconducting compounds, Ba(Fe1-xCox)2As2. We found that the oscillation amplitude exhibits an interesting temperature dependence that 2 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS Date Submitted: 6/18/2015 FWP#: 10017 appears to be only associated with the spin-density-wave phase. Furthermore, a phase shift is also observed at low temperatures. Data analysis is still in process. During this beamtime, we also characterized the ultrafast coherent lattice response in a related compound FeSe film ( of thickness of 60 u.c.), grown by Dr. Moore/ Z. X. Shen group in another FWP. A complementary time-resolved ARPES measurement to directly reveal the timeevolution of the electronic states is also in progress by Dr. Kirchmann/Z. X. Shen group in another FWP. We have been using the novel capabilities of the MEC hutch at LCLS to conduct time-resolved dynamic compression experiments. We observed, for the first time, crystallization from an amorphous starting material under shock compression using in-situ X-ray diffraction (XRD). Time-resolved XRD was used to study the nucleation and growth of nano-crystalline stishovite grains and determine grain size as a function of time after shock loading. Data collected up to 33.6 GPa showed nucleation as early as 1.4 ns, fast growth, 22 nm/ns and find data trends to match a coalescence grain growth mechanism rather than diffusion-based. A campaign on liquid and crystalline H2O (ice Ih) was successful providing the first shock-driven diffraction data on H2O and showing evidence of liquid water shock freezing to ice VII by 5 GPa in 10’s of nanoseconds. From our diffraction, ice X is observed at 1.6 Mbar – helping to bound the onset of the predicted superionic phase. We have also studied shock-driven plasticity, strength, deformation mechanism, phase transitions, and resolidification on release in several metals: Ti, Ce, Fe, etc. Completed studies using both the LCLS and laboratory-scale THz pump-probe measurements demonstrating giant modulations in the nonlinear optical susceptibility of ferroelectric thin films. This work opens up new opportunities for electric-field gating of nonlinear optical devices and provides a new understanding of novel ways in which the ferroelectric polarization can be manipulated by light. Experiments at the LCLS show subpicosecond modulations in the structure factor and indicate a surprising field-driven cooling of BaTiO3 films, providing a new understanding of field-driven ultrafast electrocaloric responses in ferroelectric thin films. Measurements at the LCLS showed a new means of visualizing the structural dynamics of semiconductor nanocrystals, capturing both their breathing mode response and melting response in the limit of large stresses and strains. These measurements inform our understanding of the dynamical response of materials at their limits, in the limit of large amplitude strains. In a series of LCLS experiments on XPP, we have demonstrated high resolution with Fourier transform inelastic x-ray scattering; using two-pulse coherent control, we have unambigously demonstrated that the mechanism for generating correlated pairs of high-momentum phonon coherences is through squeezing; and applied the method to measure the 2-phonon coherent excitation spectra in PbTe, which comprises a squeezed modes in the form of combination and overtones, and demonstrated the excitation of screened LO-plasmon coupled modes. Using hard x-ray scattering we have also measured the photo-excited lattice dynamics near the charge density wave peak in the SmTe3, and in collaboration with H. Durr the generation of high frequency coherent acoustic phonons during femtosecond demagnetization in single crystal Fe films. RIXS activities: Using resonant inelastic x-ray scattering, we have discovered an unexpected doping evolution of collective excitations in the electron-doped cuprates Nd2-xCexCuO4. The energy scales of magnetic excitations increases when doping electrons into the antiferromagnetic ordered cuprates. In addition, another branch of collective modes is also observed, which emanates from the zone center and disappears at high temperatures. Since then, we continue to investigate complete doping dependence of the collective excitations in electrondoped cuprates, especially near the antiferromagnetic-superconducting phase boundary. We have performed two more RIXS experiments at Swiss Light Source and National Synchrotron Radiation Research Center to measure samples with different dopings across the AFM-SC phase boundary. Preliminary data analysis suggests an abrupt change of the magnetic excitations and the zone center modes across the AFM-SC phase boundary. Two modular X-ray emission spectrographs have been fully assembled and fiducialized for q-RIXS. The commissioning performed at BL6.3.2 of the ALS gives a resolving power of 1,600 at 500 eV with the commercial CCD detector. This resolving power is in agreement with the design specification. The q-RIXS endstation assembling is nearly complete, with experimental chamber already installed on the hexapod. The sample cryostat was re-developed and is expected to be completed in fall 2015. The endstation assembly is expected to be completed before the end of 2015. Theory activities: Successfully obtained 10M CPU-hours in allocations for computational simulations at NERSC. We have investigated theoretical constructions for fractional Chern insulators which possess many-body interacting topologically ordered states that have potential applications in topological quantum computation. 3 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS Date Submitted: 6/18/2015 FWP#: 10017 We developed a description for pseudospin modification in graphene driven by circularly polarized light. Performed Floquet analysis of “quantum geometry” effects in monolayer dichalcogenides driven with circularly polarized light.We characterized non-trivial, topological surface states associated with both sub-gap and above gap pumping with potential for both future experimental observation/characterization and applications. Work on high pressures: We have been studying the effect of pressure on the structural and electronic properties of transition metal chalcogenides. We have recent results on a silver chalcogenide, Ag2Se (Z. Zhao et al, Phys. Rev. B 2014), which has generated interest as potential topological insulator and a transition metal dichalcogenide, MoSe2 (Z. Zhao et al, Nature Comm. in press), which has generated interest due to their atomically thin structures and unique electronic states coupling high pressure synchrotron XRD, Raman and IR spectroscopy, temperaturedependent electrical transport measurements. Organic-inorganic hybrids form the basis for natural and synthetic functional materials because they can combine the mechanical stability and electronic properties of inorganic solids with the tunability and flexibility of organic molecules. We studied the structural and electronic changes resulting from the application of pressures up to 60 GPa on a two-dimensional Cu-Cl perovskite, through a combination of in situ synchrotron xray diffraction, electronic absorption and vibrational spectroscopy, dc conductivity measurements, and optical observations. Compression of this charge-transfer insulator yields two structural phase transitions, dramatic piezochromism, and the first instance of appreciable conductivity in CuII–Cl perovskites at high pressure. In addition, we have conducted high pressure experiments on a wide range of energy related materials including high Tc cuprates and mixed valence compounds, anode materials for Li batteries, bulk metallic glasses, and upconverting nanoparticles. We are conducting ultrafast optical and THz experiments in PbTe to elucidate the nature of the anomalous splitting of the zone-center soft TO mode which has been attributed to both extended anharmonic interactions and dynamic symmetry breaking at high temperature. We are extending these experiments to high-pressure to alter the phonon density of states and attempt to isolate the TO mode. Structural dynamics: Completed measurements probing field-driven switching in phase-change materials. These measurements show that threshold switching, the first step in the field-driven transition from amorphous to crystalline phase, can be driven on picosecond time-scales, contrary to existing understanding in the field. Complementary measurements using the LCLS have been carried out using optically excitation, probing the crystal growth velocities associated with amorphous-to-crystalline transitions, which have been too fast to resolve in prior studies. Experiments using a new femtosecond electron diffraction source have been carried out probing structural dynamics in monolayer transition metal dichalcogenide films. The measurements, currently submitted for publication, capture for the first time the dynamic rippling and wrinkling dynamics, showing that nanoscale ripples with amplitudes of order 1 Å develop on picosecond time-scales, reversible at the 120 Hz repetition rate of the experiment. Complementary optical studies of related phenomena were published in ACS Nano in FY15. Expected Progress in FY2016 LCLS activities: We will perform a time-resolved x-ray scattering experiment at LCLS to investigate the CDW dynamic in YBCO. We are hoping to resolve the collective dynamics of CDW induced by single cycle of THz pulse. The beamtime has been awarded and will occur in July 2015. Followed by our successful first pulsed field experiment at LCLS, we will continue to further investigate the surprising behaviors of CDW in high temperature superconducting cuprates. In the next beamtime, we plan to map out the boundary of the field-induced CDW in the field-temperature phase diagram. We will apply coherent control techniques to demonstrate for the first time selective excitation of high q phonons using optical excitation. If successful this will provide a new mechanism for controlling and probing matter both in and out of equilibrium. We will apply our new method of fourier-transform inelastic x-ray scattering to measure ther relative roles of anisotropic electron-phonon coupling and Fermi-surface nesting in CDW systems including HTSC. RIXS activities: 4 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS Date Submitted: 6/18/2015 FWP#: 10017 Inspired by our discoveries on electron-doped cuprates, we will perform high resolution RIXS experiment on hole-doped cuprates, La2-xSrxCuO4 near the antiferromangetic phase boundary in the lightly doped regime. Magnetic excitations and its relation to the spin density wave state will be investigated. We are also awarded the first user beamtime at ESRF to perform experiment with the newly commissioned ultrahigh resolution RIXS spectrometer (energy resolution ~ 50 meV or better). We will use this spectrometer to investigate the phonon excitations in the RIXS spectrum, which contain direct information about electronphonon coupling strength at different momentum. We have chosen to study single-layer and double layer Bibase superconducting cuprates. Commission experiments of q-RIXS endstation will be conducted at ALS. Using its unique capability of high data acquisition efficiency and continuously variable spectrometer angle, we plan to perform energy-resolved resonant diffraction and momentum-resolved RIXS measurements on classical correlated materials. We also expect to perform the first time-resolved q-RIXS experiment at LCLS. We plan to explore the dynamic of excitons in transition metal diachalcogenides using RIXS. Theory activities: Continue development of Floquet codes to investigate “quantum geometry” in transition metal dichalcogenides with potential applications in “valleytronics”. Continue to refine tight-binding models obtained from ab initio band structure calculations for monolayer dichalcogenides with emphasis on a Wannier description of a larger number of valence and conduction band states. Continued characterization of experimentally realizable topological phases and surface states with symmetry classifications and predictions for realistic experimental probes. Investigate “valley Hall effect” applications in “valleytronics” and tuning these effects with changes to material parameters and applied fields. High pressures: We will continue to work on the dynamic strength of materials under dynamic compression (MEC, LCLS) and work on high pressure phase transition kinetics in metals and simple oxides. We will continue our work on transition metal chalcogenides looking at Ag2X and MoX2 (X = S, Se, and Te) as well as other interesting transition metal chalcogenide systems like ReS2. We plan to study the bromide analogues of the Cu-Cl hydrid perovskites, and also plan to substitute Cr2+ for Cu2+, switching from a d9 to a d4 electronic configuration. In addition, three-dimentional perovskites such as are one of the most heavily researched family of materials in recent years owing to their fruitful implementation in photovoltaic devices. We will complete studies on pressure dependence of the electron-phonon coupling and anharmonic interactions in order to better understand the stability of PbTe and related materials. Phase change materials: Continuation of studies of electric-field-driven switching in phase-change materials. Prior measurements show evidence for filamentary breakdown processes occurring on picosecond time-scales and we will employ THz pump / optical microscopy probe approaches to resolve the dynamics within a filament. Continuation of studies of ferroelectric thin films, probing switching dynamics within nanoscale electrode structures. Extensions of this work to two-dimensional perovskite films. Continuation of electron diffraction studies of monolayer transition metal dichalcogenide and extensions to multilayer samples and complex TMDC heterostructures. Application of coherent scattering techniques to probe strain dynamics and thermal transport processes while reconstructing the dynamic strain profiles and interfacial transport processes. We will apply ultrafast optical spectroscopy to examine changes in the band-structure of 2D materials, including the breaking of valley symmetry, induced by intense optical fields. Expected Progress in FY2017 We plan to continue utilizing LCLS to perform advanced x-ray scattering experiments, including time-resolved xray diffraction, time-resolved RIXS and inelastic scattering, and pulsed field experiments to address the grand challenge problems of “emergence” in and out of equilibrium. 5 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS Date Submitted: 6/18/2015 FWP#: 10017 Continue investigating the collective dynamics with high-resolution momentum RIXS measurement. In FY2017, RIXS instrument will energy resolution better than 50 meV will be operational in several synchrotron facilities in the world (e.g. ESRF, NSLS-II, and TPS). New discoveries enabled by these new instruments are expected. Thus, it is important to continue these efforts. These efforts are strategically important to the continuation of our FWP, as well as the development of a next generation time-resolved RIXS instrument at the LCLS-II that can fully utilize the self-seeded FEL and high-repetition rate. We will introduce other metals and insulators into the study on dynamic strength once our techniques have been validated. We will continue high pressure studies of 2D- and 3D- hybrid perovskites. We will continue to study transition metal chalcogenide systems at high pressure. SIMES will undergo its triannual DOE program review November 2015. A full narrative of the SIMES FWP program will be available at that time. Collaborations Bolme, Cindy, LLNL; Caracas, Razvan, Ecole Normale Superieure de Lyon; Chen, David Z., Caltech; Chen, Xiaojia, HPSTAR, China; Chow, Paul, CIW; Collins, Gilbert, LLNL; Ding, Yang, APS, ANL; dos Santos, A. ORNL; Eggert, Jon, LLNL; Eng, Peter, APS, ANL; Fratanduono, Dayne, LLNL; Goddard, William A., Caltech; Goncharov, Alexander, CIW; Greer, Julia, Caltech; Greven, Martin, U Minnesota; Haskel, Daniel, APS, ANL; Hawreliak, James, Washington State U; Hemley, Russell, Carnegie Institution of Washington; Kono, Yoshio, CIW; Kraus, Richard, LLNL; Lazicki, Amy, LLNL; Mao, Ho-kwang, CIW; Meng, Yue, CIW; Oganov, Artem, SUNY-Stony Brook; Pascarelli, Sakura, ESRF; Shen, Guoyin, CIW; Shen, Howard, George Mason University; Shahar, Anat, CIW; Shu, Jinfu, CIW; Sinogeikin, Stas, CIW; Struzhkin, Viktor, CIW; Thonhauser, Timo, Wake Forest; Tulk, Chris, ORNL; Yang, Wenge, CIW. Analytis, J G, UC Berkeley; Ando, Yoichi, Osaka University; Banerjee, Tamalika, University of Groningen; Baumberger, Felix, U Geneva; Bluhm, Hendrik, Lawrence Berkeley National Laboratory (LBNL); Chen, Cheng-Chien, Argonne National Laboratory; Chen, Yulin, Oxford University, England; Chuang, Yi-De, LBNL; Delaire, Olivier, Oak Ridge National Laboratory; Fahy, Stephen, University College Cork; Freericks, James K., Georgetown University;.; Fujimori, Atsushi, University of Tokyo, Japan, Greven, Martin, University of Minnesota; He, Rui-Hua, Boston College, Massachusetts; Hemminger,John C., UC Irvine; Hill, John, Brookhaven National Laboratory; Hussain, Zahid, LBNL; Johnson, Steven, ETH Zurich; Johnston, Steven, University of Tennessee; Kaindl, Robert A., LBNL; Kampf, Arno P., University of Augsburg; Kemper, Alexander F., LBNL; Krishnamurthy, H. R., Indian Institute of Science, Bangalore, India; Lee, Dung-Hai, UC Berkeley; Lipp, Magnus J.,LLNL; Liu , Amy Y., Georgetown University; Martin, L., UC Berkeley; Mazin, Igor I., Naval Research Laboratory; Meevasana, Worawat, Suranaree University of Technology, Thailand; Merlin, Roberto, U. Michigan; Mishchenko, Andrey S, RIKEN Advanced Science Institute, Japan; Monney, Claude, Fritz-Haber-Institut, Berlin, Germany; Nagaosa, Naoto, University of Tokyo; RIKEN Advanced Science Institute, Japan; Orenstein, Joseph, LBNL; Patthey, Luc, Paul Scherrer Institut, Switzerland; Sawatzky, George A., University of British Columbia, Canada; Scalapino, Douglas J., UC Santa Barbara; Scalettar, Richard T., UC Davis; Schmitt, Thorsten, Paul Scherrer Institute, Switzerland; Schoenlein, Robert W., LBNL; Sokolowski-Tinten, Klaus, University of Duisburg-Essen, Germany; Shastry, B. Sriram, UC Santa Cruz; Shen, Kyle M., Cornell University; Singh, Rajiv R. P., UC Davis; Stephenson, G.B., Argonne National Laboratory; Stock, Chris, NIST Center for Neutron Research; Indiana University Cyclotron Facility; Strocov, Vladimir N., Paul Scherrer Institute, Switzerland; Thomale, Ronny, University of Wurzburg, Germany; Tohyama, Takami, Kyoto University; Uchida, Shin-Ichi, University of Tokyo, Japan; van den Brink, Jeroen, IFW Dresden, Germany; van der Marel, Dirk, Université de Genève, Switzerland; van Veenendaal, Michel, Northern Illinois University, Argonne National Laboratory; Vernay, Francois, Université de Perpignan, France; Vishik, Inna, MIT; Yang, WanLi, LBNL; Yang, Wenge, CIW; Yabashi, Makina, RIKEN, Japan; Zaanen, Jan, University of Leiden, The Netherlands, Zhu, Diling, SLAC LCLS. 6 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS Date Submitted: 6/18/2015 FWP#: 10017 Publications Peer-Reviewed Journal Articles 1. Charge Density Wave in YBa2Cu3O6.67 at High Magnetic Fields, S. Gerber, H. Jang, H. Nojiri, S. Matsuzawa, Y. Yasumura, D. A. Bonn, R. Liang, H. N. Hardy, Z. Islam, A. Mehta, S. Song, M. Sikorski, D. Stefanescu, Y. Feng, S. A. Kivelson, T. P. Devereaux, Z.-X. Shen, C.-C. Kao, W.-S. Lee, D. Zhu, J.-S. Lee, submitted to Science. 2. Spatially-resolved ultrafast magnetic dynamics launched at a complex-oxide hetero-interface, A. Caviglia , R. Scherwitzl, R. Mankowsky, P. Zubko , V. Khanna , H. Bromberger, S. Wilkins, Y. D. Chuang, W. S. Lee, W. Schlotter , J. Turner, G. Dakovski, M. Minitti, J. Robinson, S. Clark, D. Jaksch, J. Triscone , J. Hill, S. Dhesi , A. Cavalleri, Accepted by Nature Materials (2015). 3. Direct characterization of photo-induced lattice dynamics in BaFe2As2. S. Gerber, K. W. Kim, Y. Zhang, D. Zhu, N. Plonka, M. Yi, G. L. Dakovski, D. Leuenberger, P. S. Kirchmann, R. G. Moore, M. Chollet, J. M. Glownia, Y. Feng, J.-S. Lee, A. Mehta, A. F. Kemper, T. Wolf, Y.-D. Chuang, Z. Hussain, C.-C. Kao, B. Moritz, Z.-X. Shen, T. P. Devereaux, and W.-S. Lee, Accepted by Nature Communication (2015). 4. Asymmetry of collective excitations in electron and hole doped cuprate superconductors, W. S. Lee, J. J. Lee, E. A. Nowadnick, S. Gerber, W. Tabis, S. W. Huang, V. N. Strocov, E. M. Motoyama, G. Yu, B. Moritz, H. Y. Huang, R. P. Wang, Y. B. Huang, W. B. Wu, C. T. Chen, D. J. Huang, M. Greven, T. Schmitt, Z. X. Shen, and T. P. Devereaux. Nature Physics 10, 883–889 (2014). 5. Direct observation of bulk charge modulations in optimally doped Bi1.5 Pb0.6 Sr1.54 CaCu2O8+d. M. Hashimoto, G. Ghiringhelli, W.-S. Lee, G. Dellea, A. Amorese, C. Mazzoli, K. Kummer, N. B. Brookes, B. Moritz, Y. Yoshida, H. Eisaki, Z. Hussain, T. P. Devereaux, Z.-X. Shen, and L. Braicovich. Phys. Rev. B 89, 220511(R) (2014). 6. Large-Amplitude Spin Dynamics Driven by a THz Pulse in Resonance with an Electromagnon. T. Kubacka, J.A. Johnson, M.C. Hoffmann, C. Vicario, S. de Jong, P. Beaud, S. Grübel, S-W. Huang, L. Huber, L. Patthey, Y-D. Chuang, J.J. Turner, G.L. Dakovski, W-S. Lee, W. Schlotter, R. G. Moore, C. Hauri, S.M. Koohpayeh, V. Scagnoli, G. Ingold, S.L. Johnson, U. Staub. Science 343, 1333 (2014). 7. Charge-orbital-lattice coupling effects in the dd excitation profile of one-dimensional cuprates. J. J. Lee, B. Moritz, W. S. Lee, M. Yi, C. J. Jia, A. P. Sorini, K. Kudo, Y. Koike, K. J. Zhou, C. Monney, V. Strocov, L. Patthey, T. Schmitt, T. P. Devereaux, and Z. X. Shen. Phys. Rev. B 89, 041104(R) (2014). 8. Melting of Charge Stripes in Vibrationally Driven La1.875Ba0.125CuO4: Assessing the Respective Roles of Electronic and Lattice Order in Frustrated Superconductors. M. Först, R. I. Tobey, H. Bromberger, S. B. Wilkins, V. Khanna, A. D. Caviglia, Y.-D. Chuang, W. S. Lee, W. F. Schlotter, J. J. Turner, M. P. Minitti, O. Krupin, Z. J. Xu, J. S. Wen, G. D. Gu, S. S. Dhesi, A. Cavalleri, and J. P. Hill. Phys. Rev. Lett. 112, 157002 (2014). 9. Persistence of magnetic order in a highly excited Cu2+ state in CuO. U. Staub, R.A. de Souza, P. Beaud, E. Möhr-Vorobeva, G. Ingold, A. Caviezel, V. Scagnoli, B. Delley, J.J. Turner, O. Krupin, W.-S. Lee, Y.-D. Chuang, L. Patthey, R.G. Moore, D. Lu, M. Yi, P.S. Kirchmann, M. Trigo, P. Denes, D. Doering, Z. Hussain, Z.X. Shen, D. Prabhakaran, A.T. Boothroyd, S.L. Johnson. Phys. Rev. B 89, 220401(R) (2014). 10. Position-Momentum Duality and Fractional Quantum Hall Effect in Chern Insulators, M. Claassen, C.-H. Lee, R. Thomale, X.-L. Qi, and T. P. Devereaux, arXiv:1502.06998, to appear in Phys. Rev. Lett. (Editor’s Suggestion). 11. Theory of Pump-Probe Photoemission in Graphene: Ultrafast Tuning of Floquet Bands and Local Pseudospin Textures, M. Sentef, M. Claassen, A. F. Kemper, B. Moritz, T. Oka, J. K. Freericks, and T. P. Devereaux, arXiv:1401.5103, to appear in Nature Commun. 12. Persistent Spin Excitations in Doped Antiferromagnets Revealed by Resonant Inelastic Light Scattering, C. J. Jia, E. A. Nowadnick, K. Wohlfeld, C.-C. Chen, S. Johnston, T. Tohyama, B. Moritz, and T. P. Devereaux, Nat. Commun. 5, 3314 (2014). 7 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS Date Submitted: 6/18/2015 FWP#: 10017 13. Densification process of GeO2 glass: High pressure transmission x-ray microscopy study, Y. Lin, Q. S. Zeng, W. Yang, and W. L. Mao, Appl. Phys. Lett. 103, 261909 (2013). 14. High-pressure Raman spectroscopy of phase change materials, W. P. Hsieh, P. Zalden, M. Wuttig, A. M. Lindenberg, and W. L. Mao, Appl. Phys. Lett. 103, 191908 (2013). 15. Evidence for photo-induced monoclinic metallic VO2 under high pressure, W.-P. Hsieh, M. Trigo, D. A.Reis, G. Andrea Artioli, L. Malavasi, and W. L. Mao, Applied Physics Letters 104, 021917 (2014). 16. Strain derivatives of Tc in HgBa2CuO4 : The CuO2 plane alone is not enough, S. Wang, J. Zhang, J. Yan, X-J Chen, V. V. Struzhkin, W. Tabis, N. Barisic, M. Chan, C. Dorow, X. Zhao, M. Greven, W. L. Mao, T. Geballe, Phys. Rev. B 89, 024515 (2014). 17. High pressure Raman and X-ray diffraction study of [121] Tetramantane, F. Yang, Y. Lin, J. E. P. Dahl, R. M. K. Carlson, W. L. Mao, J. Phys. Chem. C, doi:10.1021/jp500431 (2014). 18. Pressure induced second-order structural and electronic transition in Sr3Ir2O7, Z. Zhao, S. Wang, T. F. Qi, Q. S. Zeng, S. Hirai, P. P. Kong, L. Li, C. Park, S. J. Yuan, C. Q. Jin, G. Cao, and W. L. Mao, J. Phys.: Condens. Matter 26, 215402 (2014). 19. Tuning the crystal structure and electronic states of Ag2Se: Structural transitions and metallization under pressure, Z. Zhao, S. Wang, A. Oganov, P. Chen, Z. Liu, W. L. Mao, Phys. Rev. B 89, 180102(R) (2014). 20. Universal Fractional Non-Cubic Power Law for Density of Metallic Glasses, Q. Zeng, Y. Kono, Y. Lin, Z. Zeng, J. Wang, S. V. Sinogeikin, C. Y. Park, Y. Meng, W. Yang, H.-k. Mao, and W. L. Mao, Phys. Rev. Lett. 112, 185502 (2014). 21. Bandgap Closure and Reopening in CsAuI3 at High Pressure, Shibing Wang, Maria Baldini, Max Shapiro, Scott Riggs, Alexander F. Kemper, Zhao Zhao, Zhenxian Liu, Thomas P. Devereaux, Ted Geballe, Ian R Fisher, and Wendy L. Mao, Phys. Rev. B 89, 245109 (2014). 22. High-pressure storage of hydrogen fuel: ammonia borane and its related compounds, Y. Lin and W. L. Mao, Chin. Sci. Bull. doi:10.1007/s11434-014-0624-8 (2014). 23. Deviatoric Stress-Induced Phase Transitions in Diamantane, F. Yang, Y. Lin, J. E. P. Dahl, R. M. K. Carlson, and W. L. Mao, J. Chem. Phys. 141, 154305 (2014). 24. Pressure-Induced Conductivity and Yellow-to-Black Piezochromism in a Layered Cu–Cl Hybrid Perovskite, A. Jaffe, Y. Lin, W. L. Mao, and H. I. Karunadasa, J. Am. Chem. Soc. 137, 1673-1678 (2015). 25. Strain-Induced Modification of Optical Selection Rules in Lanthanide-Based Upconverting Nanoparticles, M. D. Wisser, M. Chea, Y. Lin, D. M. Wu, W. L. Mao, A. Salleo, and J. A. Dionne, Nano Lett. doi: 10.1021/nl504738k (2015). 26. A novel phase of Li15Si4 synthesized under pressure, Z. Zeng, N. Liu, Q. F. Zeng, Q. Zhu, A. R. Oganov, Q. S. Zeng, Y. Cui, and W. L. Mao, Adv. Energy Mat. 10.1002/aenm.201500214 (2015). 27. Magnetic excitations and phonons simultaneously studied by resonant inelastic x-ray scattering in optimally doped Bi1.5Pb0.55Sr1.6La0.4CuO6+δ, Y. Y. Peng, M. Hashimoto, M. Moretti Sala, A. Amorese, N. B. Brookes, G. Dellea, W.-S. Lee, M. Minola, T. Schmitt, Y. Yoshida, K.-J. Zhou, H. Eisaki, T. P. Devereaux, Z.-X. Shen, L. Braicovich, and G. Ghiringhelli, Submitted to Phys. Rev. B. 28. Ultrafast lattice dynamics of the electronically driven, lattice directed charge density wave in TbTe3. R. G. Moore, W. S. Lee, P. S. Kirchman, Y. D. Chuang, A. F. Kemper, M. Trigo, L. Patthey, D. H. Lu, O. Krupin, M. Yi, D. A. Reis, D. Doering, P. Denes, W. F. Schlotter, J. J. Turner, G. Hays, P. Hering, T. Benson, J. -H. Chu, T. P. Devereaux, I. R. Fisher, Z. Hussain, and Z. -X. Shen. Submitted to Phys. Rev. B 8 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS Date Submitted: 6/18/2015 FWP#: 10017 29. Pressure induced metallization with absence of structural transition in layered MoSe2, Z. Zhao, H. Zhang, H. Yuan, S. Wang, Y. Lin, Q. S. Zeng, Z. Liu, K. D. Patel, G. K. Solanki, Y. Cui, H. Y. Hwang, and W. L. Mao, Nature Comm., in press. 30. Structural transition and amorphization in compressed Hirai, Z. Zeng, and W. L. Mao, Phys. Rev. B, accepted. -Sb2O3, Z. Zhao, Q. S. Zeng, H. Zhang, S. Wang, S. 31. Ultrafast crystallization and grain growth in shock compressed SiO2, A.E. Gleason, C. Bolme, H.J. Lee, B. Nagler, E. Galtier, D. Milathianaki, J. Eggert, J. Hawreliak, D. Fratanduono, R. Kraus, G. Collins, W. Yang, and W. L. Mao, Nature Comm., in review. 32. Fractal nature of atomic arrangements in metallic glass, D. Z. Chen, C.Y. Shi, Q. An, Q.S. Zeng, W. L. Mao, W. A. Goddard, III, and J.R. Greer, Science, submitted. 33. Generalized Kitaev Models and Slave Genons, Maissam Barkeshli, Hong-Chen Jiang, Ronny Thomale, XiaoLiang Qi, Phys. Rev. Lett. 114, 026401 (2015) 34. Quantum Phase Transitions Between a Class of Symmetry Protected Topological States, Lokman Tsui, HongChen Jiang, Yuan-Ming Lu, and Dung-Hai Lee, Nuclear Physics B (2015) (In press) 35. Emergence of p+ip superconductivity in 2D strongly correlated Dirac fermions, Zheng-Cheng Gu, Hong-Chen Jiang, G. Baskaran, arXiv:1408.6820 36. Fermionic Symmetry Protected Topological Phase Induced by Interactions, Shang-Qiang Ning, Hong-Chen Jiang, Zheng-Xin Liu, arXiv:1412.0092 37. Charge modulation as fingerprints of phase-string triggered interference, Zheng Zhu, Chushun Tian, HongChen Jiang, Yang Qi, Zheng-Yu Weng, Jan Zaanen, arXiv:1412.3462 38. Dynamic structural response and deformations of monolayer MoS2 visualized by femtosecond electron diffraction, Ehren M. Mannebach, Renkai Li, Karel-Alexander Duerloo, Clara Nyby, Peter Zalden, Theodore Vecchione, Friederike Ernst, Alexander Hume Reid, Tyler Chase, Xiaozhe Shen, Stephen Weathersby, Carsten Hast, Robert Hettel, Ryan Coffee, Nick Hartmann, Alan R. Fry, Yifei Yu, Linyou Cao, Tony Heinz, Evan J. Reed, Hermann A. Dürr, Xijie Wang, Aaron M. Lindenberg, (Submitted), (2015) 39. MeV Ultrafast Electron Diffraction at SLAC, S. P. Weathersby, G. Brown, M. Centurion, T. F. Chase, R. Coffee, J. Corbett, J. P. Eichner, J. C. Frisch, A. R. Fry, M. Guehr, N. Hartmann, C. Hast, R. Hettel, R. K. Jobe, E. N. Jongewaard, J. R. Lewandowski, R. K. Li, A. M. Lindenberg, I. Makasyuk, J. E. May, D. McCormick, M. N. Nguyen, A. H. Reid, X. Shen, K. Sokolowski-Tinten, T. Vecchione, S. L. Vetter, J. Wu, J. Yang, H. A. Durr, and X. J. Wang, (Submitted), (2015). 40. How supercooled liquid phase-change materials crystallize: Snapshots after femtosecond optical excitation, Peter Zalden, Alexander von Hoegen, Patrick Landreman, Matthias Wuttig, and Aaron M. Lindenberg, (Submitted), (2015). 9 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS Date Submitted: 6/18/2015 FWP#: 10017 41. Giant terahertz-driven nonlinear response in bismuth ferrite, F. Chen, J. Goodfellow, S. Liu, I. Grinberg, M. C. Hoffmann, A.R. Damodaran, Y. Zhu, X. Zhang, I. Takeuchi, A. Rappe, L.W. Martin, H. Wen, A.M. Lindenberg, (Submitted), (2015). 42. Visualization of nanocrystal breathing modes at extreme strains, E. Szilagyi, J.S. Wittenberg, T.A. Miller, K. Lutker, F. Quirin, H. Lemke, D. Zhu, M. Chollet, J. Robinson, H. Wen, K. Sokolowski-Tinten, and A.M. Lindenberg, Nat. Commun., 6, 6577 (2015) 43. Color switching with enhanced optical contrast in ultrathin phase-change materials and semiconductors induced by femtosecond laser pulses, F.F. Schlich, P. Zalden, A.M. Lindenberg, R. Spolenak, ACS Photonics, 2 178 (2015). 44. Ultrafast electronic and structural response of monolayer MoS2 under intense photoexcitation conditions, E.M. Mannebach, K.N. Duerloo, L.A. Pellouchoud, M. Sher, S. Nah, Y. Kuo, Y. Yu, A. Marshall, L. Cao, E.J. Reed, A.M. Lindenberg, ACS Nano, 8, 10734 (2014). 45. Room Temperature Stabilization of Nanoscale Superionic Ag2Se, T. Hu, J.S. Wittenberg, A.M. Lindenberg, Nanotechnology, 25, 415705 (2014). 46. Reversible optical switching of infrared antenna resonances with ultrathin phase-change layers using femtosecond laser pulses, Ann-Katrin U. Michel, Peter Zalden, Dmitry N. Chigrin, Matthias Wuttig, Aaron M. Lindenberg, and Thomas Taubner, ACS Photonics, 1, 833 (2014) . Research highlight: "Phase-change control," Nat. Photon. 8, 812 (2014). 47. Ultrafast polarization response of an optically-trapped single ferroelectric nanowire, S. Nah, Y. Kuo, F. Chen, J. Park, R. Sinclair, A.M. Lindenberg. Nano Lett., 14, 4322 (2014). 48. Picosecond carrier recombination dynamics in chalcogen-hyperdoped silicon, M. Sher, C.B. Simmons, J.J. Krich, A.J. Akey, M.T. Winkler, D. Recht, T. Buonassisi, M.J. Aziz, A.M. Lindenberg, Appl. Phys. Lett. 105, 053905 (2014). 49. Below gap optical absorption in GaAs driven by intense, single-cycle coherent transition radiation, J. Goodfellow, M. Fuchs, D. Daranciang, S. Ghimire, F. Chen, H. Loos, D. Reis, A.S. Fisher, A.M. Lindenberg, Opt. Express 22, 17423 (2014). 50. Ultrafast terahertz-induced response of GeSbTe phase-change materials, M. Shu, P. Zalden, F. Chen, B. Weems, I. Chatzakis, F. Xiong, R. Jeyasingh, M. Hoffmann, E. Pop, H.-S.P. Wong, M. Wuttig, A.M. Lindenberg, Appl. Phys. Lett. 104, 251907 (2014). 51. Measurement of transient atomic displacements in thin films with picosecond and femtometer resolution, M. Kozina, T. Hu, J.S. Wittenberg, E. Szilagyi, M. Trigo, T.A. Miller, C. Uher, A. Damodaran, L. Martin, A. Mehta, J. Corbett, J. Safranek, D.A. Reis and A.M. Lindenberg, Struct. Dyn. 1, 034301 (2014). 52. Real-time visualization of nanocrystal solid-solid transformation pathways, J.S. Wittenberg, T.A. Miller, E. Szilagyi, K. Lutker, F. Quirin, W. Lu, H. Lemke, D. Zhu, M. Chollet, J. Robinson, H. Wen, K. Sokolowski-Tinten, A.P. Alivisatos, A.M. Lindenberg. Nano Lett., 14, 1995 (2014). 10 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Time‐Resolved Soft X-ray Materials Science at the LCLS and ALS Date Submitted: 6/18/2015 FWP#: 10017 53. Phonon Spectroscopy with Sub-meV Resolution by Femtosecond X-ray Diffuse Scattering, Diling Zhu, Aymeric Robert, Tomas Henighan, Henrik T. Lemke, Matthieu Chollet, J.~Michael Glownia, David A. Reis and Mariano Trigo, submitted to Physical Review Letters (2015). 54. Imaging transient melting of a nanocrystal using an x-ray laser,Jesse N. Clark, Loren Beitra, Gang Xiong, David M. Fritz, Henrik T. Lemke, Diling Zhu, Matthieu Chollet, Garth J. Williams, Marc Messerschmidt, Brian Abbey, Ross J. Harder, Alexander M. Korsunsky, Justin S. Wark, David A. Reis and Ian K. Robinson, Accepted PNAS (2015). 55. Generation of high-frequency strain waves during femtosecond demagnetization of Fe/MgO(001) films, T. Henighan, S. Bonetti, P. Granitzka, M. Trigo, Z. Chen, R. Kukreja, D. Higley, A. Gray, A. H. Reid, E. Jal, M. Hoffmann, M.E. Kozina, S. Song, M. Collet, D. Zhu, J. Jeong, M. G. Samant, S. S. P. Parkin, D.A. Reis, H. A. Dürr in preparation. 11 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Diamondoid Science and Applications Date Submitted: 6/18/2015 FWP#: 10018 Diamondoid Science and Applications PIs: Nicholas A. Melosh (FWP lead), Peter R. Schreiner, Z. X. Shen Staff Scientists: Jeremy Dahl Postdocs and Students: Hitoshi Ishiwata, Fei Li, Natalia Fokina, Maria Gunawan, Abolfazl Hosseini, Oana Moncea, Boryslav A. Tkachenko, Hao Yan Overview Diamondoids are unique new carbon-based nanomaterials consisting of 1–2 nanometer, fully hydrogen-terminated diamond particles. Unlike their conjugated counterparts, graphene or carbon nanotubes, the carbon atoms in diamondoids are exclusively sp3-hybridized, leading to unique electronic and mechanical properties. Diamondoids behave much like small molecules, with atomic-level uniformity, flexible chemical functionalization, and systematic series of sizes, shapes and chiralities. At the same time diamondoids offer more mechanical and chemical stability than small molecules, and vastly superior size and shape control compared to inorganic nanoparticles. This family of new carbon nanomaterials is thus an ideal platform for approaching the grand challenges of energy flow at the nanoscale and synthesis of atomically perfect new forms of matter with better precision than any other nanomaterials system. This program explores and develops diamondoids as a new class of functional nanomaterials based upon their unique electronic, mechanical, and structural properties. This includes all phases of investigation, from diamondoid isolation from petroleum, chemical functionalization, and molecular assembly, as well as electronic, optical and theoretical characterization. We have currently focused on three areas of research: synthesis, electronic properties, and thin film growth. This naturally requires the broad expertise and collaboration between a number of investigators to successfully approach tackle these problems. This approach has yielded fruit, enabling synthesis of a number of new compounds, and exploration of their structural and electronic properties. In particular the ability of these materials to control the flow of electrons and emitted electron energy at the molecular level is an exciting direction for mastering energy flow at the nanoscale. The team meets biweekly to review current progress and initiate new ideas. Progress in FY2015 As planed, we prepared Se-modified diamondoids or similarly rigid molecules. Indeed, we have succeded in preparing Se-modified diamondoids, which turned out to be rather challenging owing to the very rapid oxidation and dimerization of the selenol end groups. We developed a novel synthetic protocol than now allows access to a large variety of diamondoid (and other) selenols. These are now being used in in chalcogen self-assembly reactions to produce Cu and Ag –selenolates. These materials are unusual due to their three-atom cross section backbone, and have good electronic conductivity. Also as proposed, we prepared completely rigid, nm-sized hydrocarbon structures are accessible through the coupling of diamondoids through their secondary positions. Indeed, nanometer-sized doubly-bonded diamondoid dimers and trimers, which may be viewed as models of diamond with surface sp2-defects, were prepared from their corresponding ketones via a McMurry coupling and were characterized by spectroscopic and crystallographic methods. The neutral hydrocarbons and their radical cations were studied utilizing density functional theory (DFT) and ab initio (MP2) methods, which reproduce the experimental geometries and ionization potentials well. The van der Waals complexes of the oligomers with their radical cations that are models for the self-assembly of diamondoids, form highly delocalized and symmetric electron-deficient structures. This implies a rather high degree of -delocalization within the hydrocarbons not too dissimilar to delocalized π-systems. As a consequence, sp2-defects are thus also expected to be nonlocal, thereby leading to the observed high surface charge mobilities of diamond-like materials. In order to be able to use the diamondoid oligomers for subsequent surface attachment and modification, their C–H-bond functionalizations were studied and these provided halogen and hydroxy derivatives with conservation of unsaturation. Our studies also help elucidate graphitization and diamond surface defects. As many properties of diamond materials can be traced back to surface impurities, the preparation of such unsaturated larger diamondoid particles with well-defined structures can helps interpret these findings (e.g., EAs, IPs, fluorescence etc.). Secondly, we have developed readily accessible processes to control previously unobserved robust self-assemblies of nanodiamonds in micro- and nanocrystals through mild vapor deposition techniques. The chemical functionalization of 12 3 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Diamondoid Science and Applications Date Submitted: 6/18/2015 FWP#: 10018 uniform and discernible nanodiamonds was found to be a key parameter, and depending on the type of functional group (hydroxy, fluorine, etc.) and its position on the diamondoid, the structures of the discrete deposits vary dramatically. Thus, well-defined anisotropic structures such as rods, needles, triangles or truncated octahedra shapes were obtained, and self-assembled structures ranging from 20 nm to several hundred micrometers formed with conservation of a similar structure for a given diamondoid. Key thermodynamic data including sublimation enthalpy of diamondoid derivatives are reported, and SEM of the self-assemblies coupled with EDX analyses and XRD attest for the nature and purity of nanodiamonds crystals deposits. This attractive method is simple and outperforms in terms of deposit quality dip-coating methods we used. This vapor phase deposition approach is expected to allow for an easy formation of diamondoid nanoobjects on different types of substrates. Finally, we also developed a CVD technique for growing nanoscale diamond nanoparticles from diamondoid seeds. We investigated the critical nucleation size for diamond nucleation, and found that pentamantane, at 1.5 nm diameter and exclusively <111> surfaces was the critical seed for nucleation. This enabled well-controlled growth of diamond that can be further used for intentional inclusion of optically active defects. Expected Progress in FY2016 Among developing further methods for the preparation of an even broader variety of functional diamondoid derivatives, we will also plan the preparation of a variety of diamondoid-carbon nanotube (CNTs) adducts and / or hybrids with small graphene models such as pyrene. These adducts will be thoroughly characterized chemically and physically (especially I/V curves via STS) with a keen eye on single-molecule electronics and the dependence on the size, shape, attachment geometry, and functionalization of the diamondoids. Given the success of the self-asembly of chalcogen materials from thiol and selenol modified diamondoids we will contrinue to explore these reactions. These materials fall into a new class of two-dimensional tessellated materials that have been rolled up into tube- or wire like structures. Using the diamondoid thiols as a building block we will explore which of the 3 primary and 7 secondary tessellation constructs are synthetically accessible. These may reveal new electronic and optical properties, similar to the chemical synthetic production of graphene ribbons. With the goal in mind of producing diamonds from diamondoids, we aim at developing further methods for the synthesis of linear-chain diamond-like nanomaterials and diamantane polymers. The synthetic approach will primarily be based on template reactions of dihalogen-substituted diamondoids (starting with 4,9-dihalodiamantane), using the hollow cavities of CNTs. Under vacuum conditions, the dehalogenated intermediates spontaneously form the linear chains within the carbon nanotubes. Transmission electron microscopy will be employed to characterize the polymers. We expect that the present template-based approach will enable us to produce a diverse range of linear-chain polymers by choosing various precursor molecules. This technique may offer a new strategy for the design and synthesis of one-dimensional nanomaterials. We will continue to pursue diamond growth using diamondoids as seed particles, and explore which defects can be controllably introduced into different size nanoparticles. We hope to achieve N-V and Si-V centers in sub 5nm diameter diamond particles, which have only been feasible with diamondoid seeding. We will investigate the ultimate stability limit for these defects and measure their environmental stability and emission yield. Finally, in the context of diamondoid van der Waals bonding situations, we will re-examine and a textbook example for a very long C–C-bond: The reported 1.643 Å central bond length in propellane diamondoid 5-cyano-1,3dehydroadamantane, which computationally only amounts to about 1.58 Å. Hence, a re-determination could also be used to validate various ab initio and density functional theory (DFT) approaches that do less well regarding the inclusion of dispersion (which can be added ad hoc); we will compare these results with a series of CCSD(T)/cc-pVTZ optimized [n.n.n]propellanes. The structure should be prepared and retermined. Expected Progress in FY2017 One particular scientifically worthwhile challenge associated with diamondoids is their remarkable ability to stabilize van-der-Waals contact surface through intramolecular dispersion (cf. Schreiner et al. Nature 2011, 477, 308). This property has not been utilized, for instance in the design of novel materials and catalysts. With regard to materials, we will attempt to prepare the hexaphenylethane (an unknown molecule) analogues with substituents in the all-meta positions. The derivative with all-meta-tbutyl groups indeed is a stable molecule owing to the mutual London dispersion interactions of the tbutyl groups. Diamondoid groups in the same positions should be even more favorable as the entropic penalty (large for tbutyl substiuents) is minimized. This approach would give rise to new organic materials that can 4 13 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Diamondoid Science and Applications Date Submitted: 6/18/2015 FWP#: 10018 dissociate at higher temperature, thereby leading to two radicals per molecule and a paramagnetic organic material overall. There are very few examples of such materials that undoubtedly have a large variety of applications, especially in energy science (e.g., conversion of thermal energy into magnetic moment). In the realm of catalysis, we will further develop the use of diamondoids as sterically demanding yet dispersion energy donor binding moieties for ligands (e.g., mixed phospines and others). Finally, we plan on preparing large diamondoid rings connected through saturated and unsaturated moieties for superior adhesion to nonpolar surfaces (utilizing the “Gecko”-effect). Collaborations Prof. Andrey A. Fokin, Kiev Polytechnic Institute, Ukraine Prof. Jean-Cyrille Hierso, Université Burgogne, Dijon, France Prof. Thomas Möller, Techical University of Berlin Publications Peer-Reviewed Journal Articles 1. Toward an Understanding of Diamond sp2-Defects with Unsaturated Diamondoid Oligomer Models. Tatyana S. Zhuk, Tatyana Koso, Alexander E. Pashenko, Ngo Trung Hoc, Vladimir N. Rodionov, Michael Serafin, Peter R. Schreiner* and Andrey A Fokin* J. Am. Chem. Soc. 2015, 137, in press. DOI: 10.1021/jacs.5b01555 2. Unconventional Molecule-Resolved Current Rectification in Diamondoid-Fullerene Hybrids. Functionalized Nanodiamonds, part 44. Jason C. Randel, Francis C. Niestemski, Andrés R. Botello-Mendez, Warren Mar, Georges Ndabashimiye, Sorin Melinte, Jeremy E. P. Dahl, Robert M. K. Carlson, Ekaterina D. Butova, Andrey A. Fokin, Peter R. Schreiner, Jean-Christophe Charlier, and Hari C. Manoharan* Nature Commun. 2014, 5, 4877. DOI: 10.1038/ncomms5877. Open Access. 3. The Functionalization of Nanodiamonds (Diamondoids) as key Parameter of the Easily Controlled Self-Assembly in Micro- and Nanocrystals from the Vapor Phase. Functionalized Nanodiamonds, part 43. Maria A. Gunawan, Didier Poinsot, Bruno Domenichini, Sébastien Chevalier, Céline Dirand, Andrey A. Fokin, Peter R. Schreiner,* and JeanCyrille Hierso,* Nanoscale 2015, 8, 1956–1962. DOI: 10.1039/C4NR04442H. Open Access. 4. Selective Preparation of Diamondoid Phosphonates. Functionalized Nanodiamonds, part 44. Andrey A. Fokin,* Raisa I. Yurchenko, Boryslav A. Tkachenko, Natalie A. Fokina, Maria A. Gunawan, Didier Poinsot, Jeremy E. P. Dahl, Robert M. K. Carlson, Michael Serafin, Hélène Cattey, Jean-Cyrille Hierso,* and Peter R. Schreiner* J. Org. Chem. 2014, 79, 5369–5373. DOI: 10.1021/jo500793m 5. Functionalization of Homodiamantane: Oxygen Insertion Reactions Without Rearrangement with Dimethyldioxirane. Functionalized Nanodiamonds, part 42. Andrey A. Fokin,* Tanya S. Zhuk, Alexander E. Pashenko, Valeriy V. Osipov, Pavel A. Gunchenko, Michael Serafin, Peter R. Schreiner,* J. Org. Chem. 2014, 79, 1861–1866. DOI: 10.1021/jo4026594 6. Effects of molecular structures of carbon-based molecules on bio-lubrication. Zhou, Y., et al., Carbon, 2015. 86(0): p. 132-138. A Novel Phase of Li15Si4 Synthesized under Pressure. Zeng, Z., et al., Advanced Energy Materials, 2015: in press Laser-induced fluorescence of free diamondoid molecules. Richter, R., et al.,. Physical Chemistry Chemical Physics, 2015. 17(6): p. 4739-4749 7. 8. 14 5 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Electronic and Magnetic Structure of Quantum Materials Date Submitted: 6/18/2015 FWP#: 10027 Electronic and Magnetic Structure of Quantum Materials Principal Investigator(s): Zhi-Xun Shen, Thomas Devereaux Staff Scientists: Makoto Hashimoto, Patrick Kirchmann, DongHui Lu, Robert Moore, Brian Moritz Postdoctoral Scholars and Graduate Students: Sudi Chen, Yu He, Edwin Huang, Yvonne Kung, James Lee, Dominik Leuenberger, Wei Li, Benjamin Nosarzewski, Nachum Plonka, Slavko Rebec, Elliott Rosenberg, Jonathan Sobota, Hadas Soifer, Yao Wang, Krzysztof Wohlfeld, Shuolong Yang, Ming Yi, Jin Min Yoon, Hongyu Xiong, Chaofan Zhang,Yan Zhang, Yi Zhang Visiting Physicists: Lucio Braicovich, Giacomo Ghiringhelli, Rudolf Hackl, Di-Jinn Huang, Arno Kampf, Xianwen Sun, Shujie Tang Overview We have made substantial progress on several research fronts to advance our understanding of complex materials through advanced photoelectron spectroscopy techniques coupled with advanced numerical simulations. There are four themes of complementary experimental efforts within this FWP: to study novel superconductors and related materials, to develop in-situ materials synthesis capability, to develop time resolved photoelectron spectroscopy, and to develop spinresolved photoelectron spectroscopy, and to apply these capabilities to important contemporary material science issues. These experiments are complemented by closely integrated theoretical simulation and investigations that study model systems with strongly coupled degrees of freedom under equilibrium and non-equilibrium conditions. In the following, we outline our progress through lists of bullets. As this is a brievated version, we will only highlight key results, the full results will be included in the review document. Progress in FY2015 Direct spectroscopic evidence for the competition between the pseudogap and superconductivity in Bi2212 cuprate superconductors by studying the ARPES spectral weight (M. Hashimoto et al., Nature Mater 14, 37 (2015)). This work adds one more dimension to microscopic origin for the rich physics exhibited in the cuprate phase diagram (Invited Review: M. Hashimoto, I. M. Vishik, R.-H. He, T. P. Devereaux, Z.-X. Shen, Nature Phys 10, 483 (2014)) o Antagonistic spectral weight singularity at Tc, which is a profound signature for competition between the order parameters for the pseudogap and superconductivity. o Disappearance of the competition at p > 0.22 around Tc revealed by the doping dependence of the spectral weight singularity. o The ground state pseudogap critical point at p~0.19, which is at lower doping than p~0.22, suggesting the reentrant behavior of the pseudogap phase boundary beneath the superconducting dome in the cuprate phase diagram. o Spectral weight and spectral lineshape reproduced by simulation where density wave based pseudogap, coupling of electron to collective modes and superconductivity all contribute. o A pathway towards more quantitative characterizations of the pseudogap order and the mode. In-situ ARPES study of MBE grown FeSe films o Monolayer and multilayer FeSe films have been grown and characterized in-situ by ARPES o Robust quantum replica bands have been observed elucidating the strong, forward focused, electron-phonon interactions between the FeSe film and underlying STO substrate. Theoretical collaborations with T. Devereaux (SLAC), S. Johnston (U. TN) and D. H. Lee (Berkeley) have revealed how such strong e-p coupling with dominant forward scattering can enhance Tc in all channels and is responsible for the Tc enhancement in monolayer FeSe films (J. J. Lee et al., Nature 515, 245 (2014)). Ex-situ studies of FeSe films o The search for diamagnetic signature of superconductivity on capped FeSe films has revealed ferroelectric domains that form at the interface. Domains form with the addition of Se on the surface of STO but is 15 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Electronic and Magnetic Structure of Quantum Materials Date Submitted: 6/18/2015 FWP#: 10027 dramatically enhanced with the addition of a monolayer of FeSe capped with Se (Y. T. Cui, et al., Phys. Rev. Lett. 114, 037002 (2015)). Time-resolved photoemission studies of topological insulator compounds. o Distinguishing phonon mode energies with sub-meV separation in the time domain (J. A. Sobota et al., Phys. Rev. Lett. 113, 157401 (2014). Theory activities: o Successfully obtained 10M CPU-hours in allocations for computational simulations at NERSC. o Used quantum Monte Carlo to investigate the single-particle spectral function of the HubbardHolstein model in collaboration with S. Johnston, Tennessee, and E. A. Nowadnick, Cornell. o Performed a combined quantum Monte Carlo and small cluster exact diagonalization study which found no evidence for “orbital loop currents” in the cuprate pseudogap. o Performed a “fidelity” analysis of superconductivity in extended Hubbard models for the cuprates (arXiv). o Investigated the signatures of a sub-dominant d-wave pairing channel in iron-based superconductors using Raman scattering in collaboration with R. Hackl, WMI, Germany (PRX). o Using cluster perturbation theory we have investigated the microscopic mechanisms which give rise to the band dispersion in the Hubbard model. o We investigated entanglement and fractionalization in one-dimensional spin-orbital system using cluster perturbation theory and analytical techniques finding a cross-over between fractionalized excitations and strongly entangled spin and orbital degrees of freedom as a function of orbital splitting in collaboration with C.-C. Chen, ANL. o Continued development of state-of-the-art charge transfer full atomic multiplet code to add materials specificity to small cluster calculations for transition metal oxides using open-source, ab initio back-end software sources. Developed a new algorithm, PARADISOS, which significantly improves memory performance for small cluster exact diagonalization codes which can be used in conjunction with the PARMETIS library and full checkerboard decomposition techniques to treat Hilbert spaces in excess of 1010 elements. o Continued development of state-of-the-art small cluster codes using the Krylov subspace-based methods for efficient evaluation of wave-function time-evolution. o Developed codes used to study the interplay between strong electronic correlations and strong electron-phonon coupling in the Hubbard-Holstein model, examining the dynamics of a single photo-doped hole in the Peierls phase of a one-dimensional system. Infrastructure and equipment development o Commission the new beamline V and related experimental end station – this facility is expected to give five fold increase of the performance, and will substantially extend the photon energy range. o Design and construction of sample transfer system to couple oxide MBE system, chalcogenide MBE system and PLD system to ARPES endstation at SSRL. o Design and construction of chalcogenide MBE system to be coupled to ARPES endstation and oxide MBE for in-situ investigation of chalcogenide materials and chalcogenide/oxide heterostructures. o Design, construction and testing of 4-point probe for in-situ transport measurements of thin films. o Design and procurement of STM to couple to the MBE/ARPES system at SSRL. o Continued development of 11eV laser in collaboration with Lumeras Inc. o Continued development of spin-resolved ARPES system in collaboration with LBNL. Expected Progress in FY2016 Investigation of superconducting properties without the influence of the pseudogap in extremely overdoped Bi2212 o Simple d-wave superconducting gap with BCS-like temperature dependence on the entire Fermi surface. o Confirmed that this is an ideal system to study d-wave superconductivity in cuprates and identify the bosonic mode directly related with superconductivity without the complications from the pseudogap. Search for the re-entrant behavior of the pseudogap in the overdoped regime of the phase diagram. 16 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Electronic and Magnetic Structure of Quantum Materials Date Submitted: 6/18/2015 FWP#: 10027 Growth of Bi2212 samples near the pseudogap critical point with precise control of the doping level. Detailed temperature dependence study of the gap function to detect the pseudogap suppression and disappearance in the superconducting dome. Universal orbital-selective Mott physics in FeSe film, KFe2Se2, and Fe(Te,Se) chalcogenide systems (M. Yi et al., Nature Communications, accepted (2015)). Incoherent-coherent crossover and orbital dependent band renormalization in Fe(Te,Se) (Z. K. Liu et al., accepted by Phys. Rev. B). Origin of the nematicity in multilayer FeSe systems (Y. Zhang et al., submitted to Nature Communications; arXiv: 1503.01556). MBE of oxide films o Homoepitaxial STO films grown utilizing O-18 for investigation of isotope effect in monolayer FeSe/STO via ARPES where preliminary results have been obtained. o BaTiO3 and TiO2 films are being developed for investigation of the replica bands and O-18 isotope effect in FeSe films. o Recipes for La2CuO4, LSCO and LBCO utilizing ozone assisted MBE are under development for exploration of electronic structure evolution with dimension and epitaxial strain via in-situ ARPES and trARPES. o o Time-Resolved Photoemission studies of CDW compound CeTe3 o Momentum-dependent analysis of coherent response of amplitude and phonon modes highlights the coupling and symmetry of charge order. (D. Leuenberger et al., Phys. Rev. B (Rapid) accepted). Time-resolved photoemission studies of monolayer and multilayer FeSe/STO o Substrate-induced lattice strain softens the Se A1g mode in monolayer samples and demonstrates an abrupt phonon renormalization due to a lattice mismatch between the ultrathin film and the substrate. (S.-L. Yang et al., Nano Lett. – under consideration) Time-resolved Photoemission studies of optimally doped Bi2212 at high excitation densities o Tracking a 4THz coherent phonon mode along the Fermi surface points to an electron momentum dependent electron-phonon coupling Time-resolved Photoemission studies of optimally doped Bi2212 at low excitation densities o Energy-resolved hot electron population decay rates in the nodal region differ by 1-2 orders of magnitude from single particle decay rates, suggesting that scattering channels beyond electronphonon interaction play a significant role in the electron dynamics. (S.-L. Yang et al., Phys. Rev. Lett. – under consideration) Theory activities: o Continued refinement of state-of-the-art quantum Monte Carlo simulations. Multi-particle dynamical correlation functions, optical conductivity, and Raman response in the HubbardHolstein model over a wide range of doping. Extend studies in multi-orbital models for coupling to specific oxygen phonon modes identified in experimental studies. Investigate “cluster geometry” effects on nematic and charge density wave response functions in multi-orbital models. o Develop the framework for a single simulation capable of accessing different correlation functions such as small cluster exact diagonalization or quantum Monte Carlo for a comprehensive view of the pseudogap. o Provide additional phenomenological modeling to photoemission studies across the whole cuprate phase diagram, including specific evolution of peak-dip-hump features to understand the evolution of electron-phonon coupling with superconductivity and the pseudogap. o Extend the modified Krylov-based exact diagonalization approach to study time evolution of driven systems having charge, spin, orbital and lattice degrees of freedom. Continue to emphasize driving and relaxation between distinct states of matter such as charge density wave, spin density wave, and metallic states. Continue to investigate the possibility of “photoinduced” phase transitions in these highly correlated systems either through charge driving (applied fields) or direct photoexcitation. o Further refinement of time-domain Keldysh techniques. Investigate pump-probe photoemission in the superconducting state of d-wave superconductors and the influence of symmetry on amplitude 17 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Electronic and Magnetic Structure of Quantum Materials o Date Submitted: 6/18/2015 FWP#: 10027 mode oscillations. Continue development of codes for multi-particle response functions appropriate for Keldysh and Krylov subspace methods for systems out of equilibrium such as pump-probe optical conductivity, reflectivity, charge, and spin response functions. Deploy novel non-equilibrium numerical renormalization group approach for the single-site Anderson impurity model. Deploy charge-transfer full atomic multiplet code. Improved usability with open-source ab initio back-end support for transition metal oxide, chalcogenide, and pnictide materials. Continue infrastructure development for new beamline and end station, in-situ sample preparation, time and spinresolved experiments, and STM. Expected Progress in FY2017 Finish most of instrumentation development, focus on STM coupling and research using the new generation tools. SIMES will undergo its triannual DOE program review November 2015. A full narrative of the SIMES FWP program will be available at that time. Collaborations Ament, Luuk, Strategic Research at ASML, The Netherlands; Analytis, J G, UC Berkeley; Ando, Yoichi, Osaka University; Banerjee, Tamalika, University of Groningen; Baumberger, Felix, U Geneva; Bluhm, Hendrik, Lawrence Berkeley National Laboratory (LBNL); Cataudella, V., Universit`a di Napoli Federico II; Chen, Cheng-Chien, Argonne National Laboratory; Chen, Yulin, Oxford University, England; Cheng, Hai-Ping, University of Florida; Chuang, Yi-De, LBNL; Cuk, Tanja, UC Berkeley; Degiorgi, Leonardo, ETH Zurich, Switzerland; Freericks, James K., Georgetown University; Fujimori, Atsushi, University of Tokyo, Japan; Greven, Martin, University of Minnesota; Hackl, Rudi, Walther Meissner Institut, Bayerische Akademie der Wissenschaften, Germany; Hancock, Jason, University of Connecticut; He, Rui-Hua, Boston College, Massachusetts; Hemminger, John C., UC Irvine; Hill, John, Brookhaven National Laboratory; Hirschfeld, Peter, University of Florida; Hussain, Zahid, LBNL; Johnston, Steven, University of Tennessee; Kaindl, Robert A., LBNL; Kampf, Arno P., University of Augsburg; Kemper, Alexander F., LBNL; Kim, Changyoung, Yonsei University, South Korea; Kim, Young-June, University of Toronto, Canada; Krishnamurthy, H. R., Indian Institute of Science, Bangalore, India; Lee, Dung-Hai, UC Berkeley; Lipp, Magnus J.,LLNL; Liu , Amy Y., Georgetown University; Mazin, Igor I., Naval Research Laboratory; Meevasana, Worawat, Suranaree University of Technology, Thailand; Mishchenko, Andrey S, RIKEN Advanced Science Institute, Japan; Monney, Claude, FritzHaber-Institut, Berlin, Germany; Nagaosa, Naoto, University of Tokyo, RIKEN Advanced Science Institute, Japan; Nowadnick, Elizabeth A., Cornell, New York; Orenstein, Joseph, LBNL; Patthey, Luc, Paul Scherrer Institut, Switzerland; Sawatzky, George A., University of British Columbia, Canada; Scalapino, Douglas J., UC Santa Barbara; Scalettar, Richard T., UC Davis; Schmitt, Thorsten, Paul Scherrer Institute, Switzerland; Schoenlein, Robert W., LBNL; Shao-Horn, Young, Massachusetts Institute of Technology; Sentef, Michael A., Max Planck Institute for the Structure and Dynamics of Matter, Germany; Shastry, B. Sriram, UC Santa Cruz; Shen, Kyle M., Cornell University; Singh, Rajiv R. P., UC Davis; Stock, Chris, NIST Center for Neutron Research, Indiana University Cyclotron Facility; Strocov, Vladimir N., Paul Scherrer Institute, Switzerland; Thomale, Ronny, University of Wurzburg, Germany; Tohyama, Takami, Kyoto University; Uchida, Shin-Ichi, University of Tokyo, Japan; van den Brink, Jeroen, IFW Dresden, Germany; van der Marel, Dirk, Université de Genève, Switzerland; van Veenendaal, Michel, Northern Illinois University, Argonne National Laboratory; Vernay, Francois, Université de Perpignan, France; Vishik, Inna, MIT; Yang, WanLi, LBNL; Zaanen, Jan, University of Leiden, The Netherlands. Publications Peer-Reviewed Journal Articles 1. Fidelity study of superconductivity in extended Hubbard models, N. Plonka, C.J. Jia, Y. Wang, B. Moritz, and T. P. Devereaux, arXiv:1505.01127 [cond-mat.supr-con] 18 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Electronic and Magnetic Structure of Quantum Materials Date Submitted: 6/18/2015 FWP#: 10027 2. Amplitude mode oscillations in pump-probe photoemission spectra of electron-phonon mediated superconductors, A. F. Kemper, M. A. Sentef, B. Moritz, J. K. Freericks, and T. P. Devereaux, arXiv:1412.2762 [cond-mat.supr-con] 3. Direct characterization of photo-induced lattice dynamics in BaFe2As2, S. Gerber, K. W. Kim, Y. Zhang, D. Zhu, N. Plonka, M. Yi, G. L. Dakovski, D. Leuenberger, P. S. Kirchmann, R. G. Moore, M. Chollet, J. M. Glownia, Y. Feng, J.-S. Lee, A. Mehta, A. F. Kemper, T. Wolf, Y.-D. Chuang, Z. Hussain, C.-C. Kao, B. Moritz, Z.-X. Shen, T. P. Devereaux, and W.-S. Lee, arXiv:1412.6842 [cond-mat.str-el] (Accepted in Nature Communications) 4. Theory of Floquet band formation and local pseudospin textures in pump-probe photoemission of graphene, M. A. Sentef, M. Claassen, A. F. Kemper, B. Moritz, T. Oka, J. K. Freericks, and T. P. Devereaux, Nature Communications 6, 7047 (2015) 5. Renormalization of spectra by phase competition in the half-filled Hubbard-Holstein model, E. A. Nowadnick, S. Johnston, B. Moritz, and T. P. Devereaux, Physical Review B 91, 165127 (2015) 6. Probing LaMO3 metal and oxygen partial density of states using x-ray emission, absorption, and photoelectron spectroscopy, W. T. Hong, K. A. Stoerzinger, B. Moritz, T. P. Devereaux, W. Yang, and Y. Shao-Horn, Journal of Physical Chemistry C 119, 2063-2072 (2015) 7. Direct spectroscopic evidence for phase competition between the pseudogap and superconductivity in Bi2Sr2CaCu2O8+δ, M. Hashimoto, E. A. Nowadnick, R.-H. He, I. M. Vishik, B. Moritz, Y. He, K. Tanaka, R. G. Moore, D.H. Lu, Y. Yoshida, M. Ishikado, T. Sasagawa, K. Fujita, S. Ishida, S. Uchida, H. Eisaki, Z. Hussain, T. P. Devereaux, and Z.-X. Shen, Nature Materials 14, 37-42 (2015) 8. Balancing act: evidence for a strong subdominant d-wave pairing channel in Ba0.6K0.4Fe2As2, T. Bohm, A. F. Kemper, B. Moritz, F. Kretzschmar, B. Muschler, H.-M. Eiter, R. Hackl, T. P. Devereaux, D. J. Scalapino, and H.-H. Wen, Physical Review X 4, 041046 (2014) 9. Numerical exploration of spontaneous broken symmetries in multi-orbital Hubbard models, Y. F. Kung, C.-C. Chen, B. Moritz, S. Johnston, R. Thomale, and T. P. Devereaux, Physical Review B 90, 224507 (2014) 10. Asymmetry of collective excitations in electron- and hole-doped cuprate superconductors, W.-S. Lee, J. J. Lee, E. A. Nowadnick, S. Gerber, W. Tabis, S. W. Huang, V. N. Strocov, E. M. Motoyama, G. Yu, B. Moritz, H. Y Huang, R. P. Wang, Y. B. Huang, W. B. Wu, C. T. Chen, D. J. Huang, M. Greven, T. Schmitt, Z.-X. Shen, and T. P. Devereaux, Nature Physics 10, 883-889 (2014) 11. Effect of dynamical spectral weight redistribution on effective interactions in time-resolved spectroscopy, A. F. Kemper, M. A. Sentef, B. Moritz, J. K. Freericks, and T. P. Devereaux, Physical Review B 90, 075126 (2014) 12. Direct observation of bulk charge modulations in optimally-doped Bi1.5Pb0.6Sr1.54CaCu2O8+δ, M. Hashimoto, G. Ghiringhelli, W.-S. Lee, G. Dellea, A. Amorese, C. Mazzoli, K. Kummer, N. B. Brookes, B. Moritz, Y. Yoshida, H. Eisaki, Z. Hussain, T. P. Devereaux, Z.-X. Shen, and L. Braicovich, Physical Review B 89, 220511(R) (2014) (Editors’ Suggestion) 13. Dynamic competition between spin density wave order and superconductivity in underdoped Ba1−xKxFe2As2, M. Yi, Y. Zhang, Z. Liu, X. Ding, J.-H. Chu, A. F. Kemper, N. Plonka, B. Moritz, M. Hashimoto, S.-K. Mo, Z. Hussain, T. P. Devereaux, I. R. Fisher, H.-H. Wen, Z.-X. Shen, and D.H. Lu, Nature Communications 5, 3711 (2014) 14. Real-space visualization of remnant Mott gap and magnon excitations, Y. Wang, C.J. Jia, B. Moritz, and T. P. Devereaux, Physical Review Letters 112, 156402 (2014) 19 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Electronic and Magnetic Structure of Quantum Materials Date Submitted: 6/18/2015 FWP#: 10027 15. Persistent spin excitations in doped antiferromagnets revealed by resonant inelastic light scattering, C.J. Jia, E. A. Nowadnick, K. Wohlfeld, Y. F. Kung, C.-C. Chen, S. Johnston, T. Tohyama, B. Moritz, and T. P. Devereaux, Nature Communications 5, 3314 (2014) 16. Charge-orbital-lattice coupling effects in the dd-excitation profile of one dimensional cuprates, J. J. Lee, B. Moritz, W.-S. Lee, M. Yi, C.J. Jia, A. P. Sorini, K. Kudo, Y. Koike, K.J. Zhou, C. Monney, V. Strocov, L. Patthey, T. Schmitt, T. P. Devereaux, and Z.X. Shen, Physical Review B 89, 041104(R) (2014) (Editors’ Suggestion) 17. Examining electron-boson coupling using time-resolved spectroscopy, M. Sentef, A. F. Kemper, B. Moritz, J. K. Freericks, Z.-X. Shen, and T. P. Devereaux, Physical Review X 3, 041033 (2013) 18. Fractionalization, Entaglement, and Separation: Understanding the Collective Excitations in a SpinOrbital Chain, C.-C. Chen, M. van Veenendaal, T. P. Devereaux, K. Wohlfeld, Physical Review B 91, 165102 (2015) 19. Beyond Planck-Einstein Quanta: Amplitude driven Quantum Excitation, W. Shen, T. P. Devereaux, and J. K. Freericks, Physical Review B 90, 195104 (2014) 20. Exact Solution for High Harmonic Generation and the Response to an AC Driving Field for a Charge Density Wave Insulator, W. Shen, A. F. Kemper, T. P. Devereaux, and J. K. Freericks, Physical Review B 90, 115113 (2014) 21. Exact Solution for Bloch oscillations of a Simple Charge-Density-Wave Insultor, W. Shen, T. P. Devereaux, and J. K. Freericks, Physical Review B 89, 235129 (2014) 22. Nonequilibrium “Melting” of a Charge Density Wave Insulator via an Ultrafast Laser Pulse, W. Shen, Y. Ge, A. Y. Liu, H. R. Krishnamurthy, T. P. Devereaux, and J. K. Freericks, Physical Review Letters 112, 176404 (2014) 23. Tunneling Spectroscopy for Probing Orbital Anisotropy in Iron Pnictides, N. Plonka, A. F. Kemper, S. Graser, A. P. Kampf, and T. P. Devereaux, Physical Review B 88, 174518 (2013) 24. Spin chain in magnetic field: limitations of the large-N mean-field theory, K. Wohlfeld, C.-C. Chen, M. van Veenendaal, and T. P. Devereaux, Acta Physica Polonica A 127, 201 (2015) 25. Sitewise manipulations and Mott insulator-superfluid transition of interacting photons using superconducting circuit simulators, X.H. Deng, C.J. Jia, and C.-C. Chien, Physical Review B 91, 054515 (2015) 20 Field Work Proposal – SLAC National Accelerator Laboratory Correlated Materials – Synthesis and Physical Properties Date Submitted: 6/18/2015 FWP#: 10028 Correlated Materials – Synthesis and Physical Properties Principal Investigator(s): Ian Fisher, Theodore Geballe, Aharon Kapitulnik, Steven Kivelson & Kathryn Moler Postdoctoral Scholars and Graduate Students:, Abhimanyu Banerjee, Weejee Cho, Jiun-Haw Chu, Zheng Cui, Alan Fang, Alex Hristov, Philip Kratz, Sam Lederer, Se Joon Lim, Min Liu, Laimei Nie, Hilary Noad, Johanna Palmstrom, Elliott Rosenberg, Max Shapiro, Eric Spanton, Ilya Sochnikov, Christopher Watson, Patrick Worasaran, Qi Yang and Jiecheng Zhang Overview The overarching goal of our research is to understand, and ultimately control, emergent behavior in strongly correlated quantum materials. This broad class of materials holds promise for future applications directly relevant to energy security, affecting technologies from energy distribution, to improved power electronics, to more efficient computing. There are, however, many deep intellectual questions that need to be addressed in order to realize this potential. There are also many opportunities for the development of novel materials with improved properties. The intellectual focus of this FWP sits at the intersection of these challenges and opportunities. Our research combines synthesis, measurement and theory to coherently address questions at the heart of these issues. We use cutting edge, often unique, experimental probes to uncover novel forms of electronic order in a variety of complex materials. Our theoretical work provides a framework to understand the rich variety of possible ordered states, and guides our ongoing measurements and synthesis efforts. Big questions that we collectively address include; what are the rules and organizing principles governing emergent behavior in quantum materials? What is the nature of the coexisting and competing phases in high temperature superconductors, and how do they determine/limit the maximum critical temperature? What ordered states arise in oxide systems with strong spin-orbit coupling, both in bulk materials and at interfaces? And finally, how does quenched disorder affect quantum criticality and inhomogeneous electronic states in strongly correlated materials? Our research addresses these challenging questions in the context of a range of complex quantum materials. Progress in FY2015 Nematic component to the Hidden Order phase of URu2Si2 (Nature Communications 6, 6425 (2015).) For materials that harbor a continuous phase transition, the susceptibility of the material to various fields can be used to understand the nature of the fluctuating order and hence the nature of the ordered state. Here we use anisotropic biaxial strain to probe the nematic susceptibility of URu2Si2, a heavy fermion material for which the nature of the low temperature “hidden order“ state has defied comprehensive understanding for over 30 years. Our measurements reveal that the fluctuating order has a nematic component, confirming reports of two-fold anisotropy in the broken symmetry state and strongly constraining theoretical models of the hidden order phase. Ubiquitous signatures of nematic quantum criticality in optimally doped Fe-based superconductors (arXiv:1503.00402) From a theoretical perspective, recent treatments indicate that nematic fluctuations due to proximity to a nematic quantum critical point can provide an effective pairing interaction, which, as a consequence of the q=0 nature of the fluctuations, enhance Tc in all symmetry channels. It is therefore of considerable interest to empirically establish whether nematic fluctuations are a characteristic feature of optimally doped high temperature superconductors. In the present paper, we show that this appears to be the case for Fe-pnictide and chalcogenide superconductors by considering the representative materials Ba(Fe1-xCox)2As2 & Ba(Fe1-xNix)2As2 (i.e. electron doped), Ba1-xKxFe2As2 (hole doped), BaFe2(As1-xPx)2 (isovalent substitution) and FeTe1-xSex (the optimally substituted chalcogenide system). Furthermore, whilst the nematic susceptibility obeys a simple Curie law for optimal BaFe2(As1-xPx)2, all other cases reveal sub-Curie behavior, which we tentatively attribute to an enhanced sensitivity to disorder in a quantum critical regime. High Temperature Superconductivity in the Cuprates (Nature 518, 179 (2015).) It is almost thirty years since the disocovery of high temperature superconductivity in the cuprates. While it is common to start papers on this subject by bemoaning the lack of a complete understanding of the electronic 21 Field Work Proposal – SLAC National Accelerator Laboratory Correlated Materials – Synthesis and Physical Properties Date Submitted: 6/18/2015 FWP#: 10028 properties of these materials, in fact there has been spectacular progress made – both theoretically and experimentally. In this paper, the authors (a diverse group) articulate the basic – and widely accepted – theoretical understanding of the origin of high temperature superconductivity, its relation to quantum magnetism, why it has dwave symmetry, why there is a superconducting dome, and why the phase diagram is so complicated – riddled with “intertwined orders” of various sorts. We also carefully define the most fundamental remaining open issues in the field – most of which have relevance much more broadly to the understanding of highly correlated electron fluids in conditions in which the quasiparticle (Fermi liquid) paradigm is inadequate. Is FeSe a nematic quantum paramagnet? (arXiv:1501.00844) It has been understood for some time how a nematic phase of the sort found in the Fe based superconductors can arise from the thermal melting of a striped antiferromagnetic state. In this paper, we address the issue of how a zerotemperature ground-state nematic phase can arise due to the quantum melting (symmetry restoration due to quantum fluctuations) of either a stripe or a Neel antiferromagnet. Starting from the Neel state, in particular, the nematic phase reflects the existence of a non-trivial Berry’s phase associated with instanton (tunneling) events, which implies as well that a quantum phase transition between these two phases would be governed by a “deconfined quantum critical point.” We also construct an exactly solvable spin model which has a nematic quantum paramagnetic ground-state with remarkably short-range magnetic correlations, and present evidence that this phase arises naturally in a small but finite range of parameters in the spin-1 version of the familiar J1-J2 antiferromagnet. Evidence for broken time-reversal symmetry in the superconducting phase of URu2Si2 (Phys. Rev. B 91, 140506 (2015).) Recent experimental and theoretical interest in the superconducting phase of the heavy fermion material URu2Si2 has led to a number of proposals in which the superconducting order parameter breaks time-reversal symmetry (TRS). In this study we measured polar Kerr effect (PKE) as a function of temperature for several high-quality single crystals of URu2Si2. We find an onset of PKE below the superconducting transition that is consistent with a TRS-breaking order parameter. This effect appears to be independent of an additional, possibly extrinsic, PKE generated above the hidden order transition at THO = 17.5 K, and contains structure below Tc suggestive of additional physics within the superconducting state. Self Duality and a possible "Hall Insulator" phase near the Superconductor to Insulator Transition in twodimensional indium-oxide films (arXiv:1504.08115) We combine measurements of the longitudinal and Hall resistivities of disordered two-dimensional amorphous indium-oxide films to study the magnetic-field tuned superconductor to insulator transition (SIT) in the T→ 0 limit. We find that the transition exhibits signatures of self-duality, and separates the superconducting state from a “Hallinsulator” phase. A higher characteristic magnetic field at which the Hall resistance is T- independent marks a crossover to a Fermi-insulator, at which point the Hall resistivity reaches the normal-state value of H/nec. Further conclusions are drawn using a mapping of the SIT on the quantum Hall liquid to insulator transition. Chiral currents and trivial edge currents in topological heterostructures (submitted to Science, and unpublished data). We studied chiral edge currents in two systems. In one experiment, we studied ferromagnet insulator / topological insulator heterostructures, which should host chiral edge states, although direct demonstration has been lacking. Specifically, we used a scanning superconducting quantum interference device (SQUID) to show that current in a magnetized EuS/Bi2Se3 heterostructure flows at the edge when the Fermi level is gate-tuned to the surface band gap. We further induced micron-scale magnetic structures using the field coil of the SQUID. An edge current with chirality determined by magnetization of its surrounding domain and with magnitude dependent on the chemical potential rather than the applied current emerged at the magnetic domain boundary. Such magnetic structures, which can be created in-situ on a TI in a designed geometry, provide a versatile platform for detecting topological magnetoelectric effects and may enable the engineering of magnetically defined quantum bits, spinbased electronics, and topological quantum computation. In a somewhat related but so far unpublished experiment, we studied InAs/GaSb quantum wells, widely believed to be the second experimentally demonstrated quantum spin hall effect material. By imaging 2D current flow in InAs/GaSb quantum wells with long edges as a function of both top gate and back gate voltages, we demonstrate the existence of edge-state-dominated conduction in a regime believed to be trivial. In contrast, in these samples the regime believed to be topological has detectable edge states but also substantial bulk conductivity. These results may indicate a need for caution in interpreting experiments in quantum spin hall systems. 22 Field Work Proposal – SLAC National Accelerator Laboratory Correlated Materials – Synthesis and Physical Properties Date Submitted: 6/18/2015 FWP#: 10028 Real-time and -space imaging of spontaneous magnetic fluctuations in spin ice Ho2Ti2O7 (Manuscript in preparation). A wide variety of frustrated magnets, both classical and quantum, develop highly degenerate, correlated ground states. In theory, quasiparticles of an exotic nature emerge above the ground state as topological defects; in classical spin ices, these take the form of magnetic monopoles. In practice, the activation energies determined from magnetization measurements of classical spin ices at sub Kelvin temperatures are higher than those expected for monopole diffusion. The limits of the distributions of these energies, and therefore limits on the relevance of the monopole picture, are not fully understood, in part because of the scarcity of experimental tools that can directly probe monopole dynamics. Here, we use Superconducting QUantum Interference Device (SQUID) microscopy on classical spin ice Ho2Ti2O7 to image the magnetization at the surface. We found and quantified a a magnetization landscape that fluctuates in both time and space. The temperature, spatial, and frequency dependence of these fluctuations reveals a narrow distribution of activation energies. This distribution is consistent with a finite energy cost for spin flipping, or equivalently to strongly bound pairs of defects in the spin ice state rather than ‘freely’ propagating monopoles. Our technique will powerfully complement other techniques in studies of emergent phenomena in various classical and quantum magnets by enabling real-space-, -time-, and -energy- resolved detection of spin fluctuations. Expected Progress in FY2016 Elastoresistance measurements of HTSC cuprates We have just begun a series of elastoresistance measurements of single crystals of La2-xSrxCuO4 with the aim of investigating the evolution of the nematic susceptibility across the phase diagram in this representative cuprate superconductor. The measurements will potentially address the origin of the HTT to LTO transition and the presence/absence of fluctuating stripe order on the underdoped side of the phase diagram. Development/extension of the elastoresistance technique as a probe of broken symmetries In collaboration with S. Raghu (another SIMES FWP), we are currently working to extend the elastoresistance technique in order to address subtle forms of broken symmetry that might be relevant to cuprates and potentially other strongly correlated materials. Specific ideas include use of sheer conductivity to probe broken mirror symmetry, and a generalization of the elastoresistivity in the presence of a magnetic field. Studies of broken time-reversal symmetry in unconventional superconductors Our grand plan is to use Kerr effect measurements to detect signatures of time reversal symmetry breaking (TRSB) in unconventional superconductors. Here we want to further study UPt3, which was a previous highlight from our group, but look at the b-axis of this system. While b-axis crystals are difficult to make, our collaborators at Northwestern succeeded in fabricating high quality crystals. In addition, we plan to study CeCoIn5, a heavy fermion system with simple d-wave symmetry, thus, TRSB is not expected, and PrOs4Sb12 where two superconducting transitions have been detected, but ambiguity exists with respect to TRSB of each of them. Emergence of Metallic states near the superconductor-insulator transition for films with weak disorder The magnetic-field tuned superconductor to insulator transition (SIT) has been studied in a variety of amorphous 2D. An important advancement in this field is that it is now accepted that in “weakly disordered” films (with normal state resistivity small compared to the quantum of resistance, h/e2), the superconducting state gives way to an anomalous metallic phase with a resistivity that extrapolates to a non-zero value as T → 0; this “superconductor to metal” transition occurs at a magnetic field small compared to the mean- field Hc2. We plan to measure the Hall effect of this phase to verify how much of a “superconducting character it possesses. Enhanced superconducting transition temperature due to tetragonal domains in two-dimensionally doped SrTiO3 Strontium titanate is the most dilute superconductor known and is also one of the most important substrates for growing novel superconductors. Nevertheless, the mechanism of superconductivity in strontium titanate and it relationship to the structure and dielectric properties are not well understood. We use a scanning superconducting quantum interference device susceptometer to image the diamagnetic response of two-dimensionally niobium-doped SrTiO3 as a function of temperature. We find that regions of the sample, with a pattern that is characteristic of twin domains, have a larger critical temperature, Tc, temperature than their surroundings. The observed change in critical temperature, Tc / Tc, is of order the dielectric constant anisotropy and much larger than the tetragonal variation of the lattice constant. These results indicate the likely importance of dielectric properties in explaining the superconductivity, and provide a phenomenon which quantitative theories of the superconductivity must explain. 23 Field Work Proposal – SLAC National Accelerator Laboratory Correlated Materials – Synthesis and Physical Properties Date Submitted: 6/18/2015 FWP#: 10028 Exotic phases in LBCO In collaboration with Steve Kivelson (this FWP) and the Brookhaven group, we are studying the time and space dependence of the magnetic landscape in LBCO. Expected Progress in FY2017 Elastoresistance measurements of strongly correlated materials We will continue our investigation of the elastoresistance of several families of strongly correlated materials. We will also seek new materials that reveal electronic nematic phases, the study of which might shed light on the significance of nematic fluctuations and nematic quantum criticality in the Fe pnictides and cuprate HTSCs. Theory of quantum nematic phases of correlated electronic systems We will consider our theoretical studies of the properties of quantum nematic phases in diverse examples of highly correlated electronic systems, including quantum Hall systems, high temperature superconducting transition metal oxides, and possibly new materials which exhibit appropriate forms of orbital ordering. Development of all optical thermal diffusivity measurement of correlated materials This is a new project that we are currently assessing. While such method was use in the past to study high Tc materials, current interest in anisotropies due to charge order states suggest that this measurement can be of great importance to detect related phase transitions. It can also be an important complementary measurement to Fisher group’s elastoresistance measurements of strongly correlated materials. Magnetic imaging of strongly correlated materials We will investigate the lanscapes of magnetism, magnetic susceptibility, and magnetic fluctuations of several families of strongly correlated materials, concentrating particularly on materials of interest to our colleagues in this FWP. SIMES will undergo its triannual DOE program review November 2015. A full narrative of the SIMES FWP program will be available at that time. Collaborations A. Andreev (U. of Washington); Maissam Barkeshli (UCSB); E. Bauer (LANL); L. Balicas (NHMFL); K. Behnia (ESPCI, Paris); Christopher Bell (University of Bristol, England); E. Berg (Weizmann); G. S. Boebinger (NHMFL); Nicholas Breznay (LBNL); V. Brouet (Universite Paris Sud, France); S. Brown (UCLA); Christoph Brüne (Wuerzburg); S.L. Budko (Ames Laboaratory); Hartmut Buhmann (Wuerzburg); A. Carrington (Bristol, UK); A. Caldea (Oxford, UK); P. Canfield (Ames); R. Cava (Princeton University); S. Chandan (Purdue); A. V. Chubukov (U. of Wisconsin); SB. Chung (UCLA); J. R. Cooper (Cambridge, UK); Y. Cui (Stanford University); N. Curro (UC Davis); L. DeGiorgi (ETH Zurich, Switzerland); T. P. Devereaux (Stanford); Rui Rui Du (Rice); S. Dugdale (Bristol, UK); H. Durr (Stanford University); C. B. Eom (Wisconsin); A. Finkelstein (Texas A&M); E. M. Forgan (Birmingham, UK); E. Fradkin (UIUC); M. Gabay(LPS, Orsay, France); D. Goldhaber-Gordon (Stanford); S. A. Grigera (St. Andrews); R. Hackl (WMI, Germany); W. P. Halperin (Northwestern); R-H. He (BC); J-P. Hu (Purdue); J. Hulliger (University of Berne, Switzerland); Z. Hussain (LBL); N. Hussey (Bristol, UK); Harold Y. Hwang (Stanford University); Z. Islam (APS, ANL); M. Jaime (NHMFL); B. Kalisky (Bar-Ilan University, Israel); A. Kaminsky (Ames Lab); A. Keles (University of Washington), E-A. Kim (Cornell); Y-J Kim (Toronto), R. Knight (Stanford); M. Kramer (Ames Lab); T. Lemberger (Ohio State University); D-H. Lee (UCB); A. P. M. Mackenzie (St Andrews, UK); Jochen Mannhart (Max-Planck Stuttgart, Germany); M. B. Maple (UCSD); C. Marcus (University of Copenhagen, Denmark); Nadya Mason (Urbana); R. McDonald (NHMFL); J. Mesot (PSI); D. Mihailovic (Lubljana, Slovenia); F. Milleto-Fabrizio (University of Naples, Italy); L Molenkamp (Wuerzburg); J. Moodera (MIT); R. G. Moore (Stanford); J. Orenstein (LBNL); A. Palevski (Tel Aviv University, Israel); S. Parameswaran (UCB); R. Prozorov (Ames); A. Reid (Stanford University); A. W. Rost (St. Andrews); M. Rudner (Harvard); Andres Santander-Syro (U. of Paris, Orsay); R. Shankar (Yale); Yoni Shatner (Wiezmann), Z-X. Shen (Stanford); K. Shih (University of Texas, Austin); B.Z. Spivak (U of Washington); S. Stemmer (U.C.S.B.); M. Stone (Oak Ridge); M. Tanatar (Ames Laboratory); M. F. Toney (SSRL); S. Tozer (NHMFL); J. Tranquada (BNL); Fa Wang (Peking University); K. Wang (UCLA); S.R. White (UCI); M. Wolf (Berlin, Germany); M. Wuttig (RWTH, Aachen, Germany); Q. Xue (Tsinghua University, China); Hong Yao (Tsinghua). 24 Field Work Proposal – SLAC National Accelerator Laboratory Correlated Materials – Synthesis and Physical Properties Date Submitted: 6/18/2015 FWP#: 10028 Publications for FY14 & FY15 (Oct 1st 2013 to date) Oct 1st 2013 – Dec 31st 2013 1) Evidence from tunneling spectroscopy for a quasi-one dimensional origin of superconductivity in Sr2RuO4, I. A. Firmo, S. Lederer, C. Lupien, A. P. Mackenzie, J. C. Davis and S. A. Kivelson, Phys. Rev. B 88, 134521 (2013). (Published 28 October 2013) 2) Locally enhanced conductivity due to tetragonal domain structure in LaAlO3/SrTiO3 heterointerfaces, Beena Kalisky , Eric Spanton, Hilary Noad , John Kirtley, Katja Nowack , Christopher Bell , Hiroki Sato , Masayuki Hosoda , Yanwu Xie , Yasuyuki Hikita , Carsten Woltmann , Georg Pfanzelt , Rainer Jany , Christoph Richter , Harold Hwang , Jochen Mannhart, Kathryn Moler Nature Materials 12, pp 1091-1095 (Published 01 December 2013). 3) Correlations and renormalization of the electron-phonon coupling in the honeycomb Hubbard ladder and superconductivity in polyacene, G. Karakonstantakis, L. Liu, R. Thomale, and S. A. Kivelson, Phys. Rev. B 88, 224512 (2013). (Published 27 December 2013) 2014 4) Transport near a quantum critical point in BaFe2(As1-xPx)2, James G. Analytis, H-H. Kuo, Ross D. McDonald, MarkWartenbe, P. M. C. Rourke, N. E. Hussey and I. R. Fisher, Nature Physics 10, 194–197 (2014) [4 pages] – Published online 19 January 2014 5) Evidence of Chiral Order in the Charge-Ordered Phase of Superconducting La1.875Ba0.125CuO4 Single Crystals Using Polar Kerr-Effect Measurements, Hovnatan Karapetyan, Jing Xia, M. Hucker, G. D. Gu, J. M. Tranquada, M.M. Fejer, A. Kapitulnik, Phys. Rev. Lett 112, 047003 (2014) Published 30 January 2014 6) Hysteretic behavior in the optical response of the underdoped Fe-arsenide Ba(Fe1-xCox)2As2 in the electronic nematic phase C. Mirri, A. Dusza, S. Bastelberger, J.-H. Chu, H.-H. Kuo, I. R. Fisher, and L. Degiorgi, Phys. Rev. B 89, 060501(R) (2014) [5 pages] – Published 7 February 2014 7) Pulsed Laser Deposition of High-Quality Thin Films of the Insulating Ferromagnet EuS Qi I. Yang, Jinfeng Zhao, Li Zhang, Merav Dolev, Alexander D. Fried, Ann F. Marshall, Subhash H. Risbud, Aharon Kapitulnik, Appl. Phys. Lett. 104, 082402 (2014) (Published 25 February 2014) 8) Spectrally resolved femtosecond reflectivity relaxation dynamics in undoped spin-density wave 122-structure ironbased pnictides A. Pogrebna, N.Vujicic, T. Mertelj, T. Borzda, G. Cao, Z. A. Xu, J.-H. Chu, I. R. Fisher, and D. Mihailovic, Phys. Rev. B 89, 165131 (2014) [9 pages] – Published 24 April 2014 9) Dynamic competition between spin-density wave order and superconductivity in underdoped Ba1-xKxFe2As2 M. Yi, Y. Zhang, Z.-K. Liu, X. Ding, J.-H. Chu, A.F. Kemper, N. Plonka, B. Moritz, M. Hashimoto, S.-K. Mo, Z. Hussain, T.P. Devereaux, I.R. Fisher, H.H. Wen, Z.-X. Shen & D.H. Lu, Nature Communications DOI: 10.1038/ncomms4711 [7 pages] – Published 25 April 2014 10) Spectrally resolved femtosecond reflectivity relaxation dynamics in undoped spin-density wave 122-structure ironbased pnictides A. Pogrebna, N.Vujicic, T. Mertelj, T. Borzda, G. Cao, Z. A. Xu, J.-H. Chu, I. R. Fisher, and D. Mihailovic, Phys. Rev. B 89, 165131 (2014) [9 pages] – Published 24 April 2014 11) Dynamic competition between spin-density wave order and superconductivity in underdoped Ba1-xKxFe2As2 M. Yi, Y. Zhang, Z.-K. Liu, X. Ding, J.-H. Chu*, A.F. Kemper, N. Plonka, B. Moritz, M. Hashimoto, S.-K. Mo, Z. Hussain, T.P. Devereaux, I.R. Fisher, H.H. Wen, Z.-X. Shen & D.H. Lu, Nature Communications 5, 3711 (2014) [7 pages] DOI: 10.1038/ncomms4711 – Published 25 April 2014 25 Field Work Proposal – SLAC National Accelerator Laboratory Correlated Materials – Synthesis and Physical Properties Date Submitted: 6/18/2015 FWP#: 10028 12) Quenched disorder and vestigial nematicity in the pseudo-gap regime of the cuprates, L Nie, G. Tarjus, and S. A. Kivelson, Proceedings of the National Academy of Sciences, 111, 7980-7985 (2014).(Published June 3rd 2014) 13) Effect of Disorder on the Resistivity Anisotropy Near the Electronic Nematic Phase Transition in Pure and ElectronDoped BaFe2As2 Hsueh-Hui Kuo and Ian R. Fisher, Phys. Rev. Lett 112, 227001 (2014) [5 pages] – Published 4 June 2014 14) Observation of Broken Time-Reversal Symmetry in the B Phase of the Heavy Fermion Superconductor UPt3 E. R. Schemm, W. J. Gannon, C. Wishne, W. P. Halperin, A. Kapitulnik, Science 345, 190-193 (2014). Published 11th July 2014. 15) Images of edge current in InAs/GaSb quantum wells Eric M. Spanton, Katja C. Nowack, Lingjie Du, Gerald Sullivan, Rui-Rui Du, Kathryn A. Moler Physical Review Letters, 113, 026804 (2014). Published 11 July 2014 16) Ultrafast electron dynamics in the topological insulator Bi2Se3 studied by time-resolved photoemission spectroscopy J.A. Sobota, S.-L. Yang, D. Leuenberger, A.F. Kemper, J.G. Analytis*, I.R. Fisher, P.S. Kirchmann, T.P. Devereaux, Z.-X. Shen, Journal of Electron Spectroscopy and Related Phenomena 195, 249–257 (2014) [8 pages] – Published 5 Sept 2014 17) Distinguishing bulk and surface electron-phonon coupling in the topological insulator Bi2Se3 using time-resolved photoemission spectroscopy J. A. Sobota, S.-L. Yang, D. Leuenberger, A. F. Kemper, J. G. Analytis, I. R. Fisher, P. S. Kirchmann, T. P. Devereaux, and Z.-X. Shen Phys. Rev. Lett. 113, 157401 (2014) [4 pages] – Published 10 October 2014 18) Nematic-driven anisotropic electronic properties of underdoped detwinned Ba(Fe1-xCox)2As2 revealed by optical spectroscopy C. Mirri, A. Dusza, S. Bastelberger, J.-H. Chu*, H.-H. Kuo*, I. R. Fisher, and L. Degiorgi Phys. Rev. B 90, 155125 (2014) [7 pages] – Published 21 October 2014 2015 (to date) 19) Erratum: Kerr effect as evidence of gyrotropic order in the cuprates [Phys. Rev. B 87, 115116 (2013)] Pavan Hosur, A. Kapitulnik, S. A. Kivelson, J. Orenstein, S. Raghu, W. Cho, and A. Fried Phys. Rev. B 91, 039908 – Published 26 January 2015 20) Evidence for a nematic component to the hidden-order parameter in URu2Si2 from differential elastoresistance measurements Scott C. Riggs, M.C. Shapiro, Akash V Maharaj, S. Raghu, E.D. Bauer, R.E. Baumbach, P. Giraldo-Gallo, Mark Wartenbe & I.R. Fisher Nature Communications 6, 6425 (2015) doi:10.1038/ncomms7425 [6 pages] – Published 06 March 2015 21) Wave vector dependent electron-phonon coupling drives charge-density-wave formation in TbTe3, M. Maschek, S. Rosenkranz, R. Heid, A. H. Said, P. Giraldo-Gallo, I. R. Fisher, F. Weber arXiv:1410.7592 22) Ubiquitous signatures of nematic quantum criticality in optimally doped Fe-based superconductors Hsueh-Hui Kuo, Jiun-Haw Chu, Steven A. Kivelson, Ian R. Fisher arXiv:1503.00402 23) Transfer of spectral weight across the gap of Sr2IrO4 induced by La doping V. Brouet, J. Mansart, L. Perfetti, C. Piovera, I. Vobornik, P. Le Fèvre, F. Bertran, S. C. Riggs, M. C. Shapiro, P. Giraldo-Gallo, I. R. Fisher, arXiv:1503.08120 26 Field Work Proposal – SLAC National Accelerator Laboratory Correlated Materials – Synthesis and Physical Properties Date Submitted: 6/18/2015 FWP#: 10028 24) Shearconductivity as a probe of broken mirror symmetries Patrik Hlobil, Akash V. Maharaj, Pavan Hosur, M.C. Shapiro, I.R. Fisher, S. Raghu arXiv:1504.05972 25) Pressure dependence of the charge-density-wave and superconducting states in GdTe3, TbTe3, and DyTe3, D. A. Zocco, J. J. Hamlin, K. Grube, J.-H. Chu, H.-H. Kuo, I. R. Fisher, and M. B. Maple Phys. Rev. B 91, 205114 (2015) [7 pages] – Published 14 May 2015 26) High Temperature Superconductivity in the Cuprates B. Keimer, S. A. Kivelsin, M. Norman, S. Uchida, and J. Zaanen, Nature 518, 179 (2015). 27) Are there quantum oscillations in an incommensurate charge density wave? Yi Zhang, Akash V. Maharaj, and Steven A. Kivelson, Phys. Rev. B 91, 085105 (2015). 28) Theory of Intertwined Orders in High Temperature Superconductors Eduardo Fradkin, Steven A. Kivelsoon, and John M. Tranquada, Reviews of Modern Physics (in press) 2015. 29) Theory of disordered unconventional superconductors A. Keles, A. V. Andreev, S. A. Kivelson, and B.Z. Spivak, JETP 119, 1109 (2015). 30) Is FeSe a nematic quantum paramagnet? Fa Wang, S.A. Kivelson, and D-H. Lee, arXiv:1501.00844. 31) Is there a hidden chiral density-wave in the iron-based superconductors? R.M. Fernandes, S. A. Kivelson, and E. Berg, arXiv:1504.03656. 32) Notes on Constraints for the Observation of Polar Kerr Effect in Complex Materials, Aharon Kapitulnik, Physica B 460, 151-158 (2015). 33) Evidence for broken time-reversal symmetry in the superconducting phase of URu2Si2, E. R. Schemm, R. E. Baumbach, P. H. Tobash, F. Ronning, E. D. Bauer, A. Kapitulnik, Phys. Rev. B 91, 140506 (2015). 34) Self Duality and a possible "Hall Insulator" phase near the Superconductor to Insulator Transition in twodimensional indium-oxide films, Nicholas P. Breznay, Myles A. Steiner, Steven A. Kivelson, Aharon Kapitulnik, arXiv:1504.08115 35) Nonsinusoidal Current-Phase Relationship in Josephson Junctions from the 3D Topological Insulator HgTe Ilya Sochnikov, Luis Maier, Christopher A. Watson, John R. Kirtley, Charles Gould, Grigory Tkachov, Ewelina M. Hankiewicz, Christoph Brüne, Hartmut Buhmann, Laurens W. Molenkamp, and Kathryn A. Moler, Phys. Rev. Lett. 114, 066801 – Published 9 February 2015 27 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Spin Physics Date Submitted: 6/18/2015 FWP#: 10029 Spin Physics Principal Investigator(s): David Goldhaber-Gordon, Hari Manoharan, Joeseph Orenstein, Shoucheng Zhang Postdoctoral Scholars and Graduate Students: John Bartel, Andrew Bestwick, Derrick Boone, Eric Chatterjee, Alex Contryman, Alex Fragapane, Alexander Hughes, Francis Niestemski, Shreyas Patankar, Jason Randel, Dominik Rastawicki, Jing Wang, and Gang Xu Overview The Spin Physics program investigates novel phenomena arising from spin interactions and spin-orbit coupling in solids. In conventional semiconductors, spin-orbit coupling gives the possibility of electric manipulation of the spin degrees of freedom, which can be used for data storage and information processing. More recently, it is realized that spin-orbit coupling can lead to a fundamentally new state of matter, the topological insulator. These materials have an energy gap in the bulk, and a conducting topological state on the surface. The spin program develops theoretical concepts and experimental tools to investigate these novel effects. Progress in FY2015 Goldhaber-Gordon group published a paper in Physical Review Letters demonstrating a nearly ideal realization of the quantum anomalous Hall (QAH) effect. By manipulating an unexpected magnetocaloric effect, they drove a magnetically-doped topological insulator film to within one part per 10,000 of quantized conductance. This is an important confirmation of topological edge transport, as predicted by Zhang and his group. Goldhaber-Gordon group is designing new structures to manipulate magnetic domains and control the resulting conductance channels. Goldhaber-Gordon group also developed fabrication capabilities to make back-gated HgTe/HgCdTe heterostructures, allowing for studies of junctions between quantum Hall and quantum spin Hall edge states. In collaboration with Zhang group, they are working toward an understanding of the interplay of different forms of topological order, specifically how chiral edge states of quantum Hall systems equilibrate with helical edge states of quantum spin Hall systems. Manoharan, Zhang, and Orenstein worked together on the half-metallic surface state of NaCoO2 as a platform for topological superconductivity and Majorana fermions though the mechanism of s-wave superconductivity proximity effect. Manoharan performed STM measurements on the surface states of NaCoO2, confirmed a bulk bandgap > 1eV, and distinguished the p-type doping surface region expected by theory to harbor magnetic surface states. The observed local density of states (LDOS) by STM experiments quantitatively agree with Zhang group's ab initio calculations, indicating the single spin-polarized Fermi surface on NaCoO2. The single surface state was confirmed by ARPES experiments done by Yulin Chen. The magnetization of the surface states was confirmed by measurements of the magneto-optical Kerr effect by Orenstein group revealing a remnant magnetization of the state with a critical temperature T ~ 15 K, in agreement with T-dependent scanning tunneling spectroscopy performed by Manoharan group. Manoharan discovered a spin splitting of a 1D flatband in a linear topological defect assembled into molecular graphene, which also becomes half-metallic at the proper doping. Manoharan and Zhang began a joint theory-experimental investigation to explain these results. Manoharan published in Nature Communications a work on emergent current rectification observed from diamondoids being investigated for nanoscale spin probes, and has other papers pending on emergent granularity near superconducting-insulating transitions and the emergent half-metallic surface states. Zhang’s group has theoretically predicted a series of new phenomena on the quantum anomalous Hall (QAH) effect in Cr doped topological insulator (Sb,Bi)2Te3, many of which have been confirmed experimentally. In one paper, we study the critical phenomenon of the QAH plateau transition in magnetic topological insulators. We predict that there is an intermediate plateau with zero Hall conductance xy occurring at the coercive field, and accordingly the longitudinal conductance xx has double peaks at the coercive field. This prediction has been confirmed by two different experimental groups in two recent papers. In another paper, we predict the electric-field control of ferromagnetism in thin films of insulating magnetically dopped topological insulator (Sb,Bi)2Te3. We propose that the application of an electric field could reduce the magnetism of the thin film and therefore could induce a quantum phase transition from ferromagnetism to paramagnetism, which has also been confirmed experimentally (private communication). Based on this property, we further propose a topological transistor device for voltage based writing of magnetic random access memories in magnetic tunnel junctions, which may lead to electronic applications of topological insulators. 28 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Spin Physics Date Submitted: 6/18/2015 FWP#: 10029 Zhang’s group has theoretically studied and predicted new materials for quantum anomalous Hall effect and quantum spin Hall (QSH) effect in several papers. In the first paper, we propose that in ferromagnetic EuO/CdO quantum well, the QAH effect can be realized with high Curie temperature and a larger band gap. In the second paper, we propose junction quantum wells comprising II-VI, III-V or IV semiconductors as a large class of new materials realizing the QSH effect and the QAH effect (with magnetic doping) with a larger band gap. In the third paper, we propose realizing the QAH effect in more conventional diluted magnetic semiconductors with magnetically doped InAs/GaSb type-II quantum wells. In the fourth paper, we predict that a monolayer of Cr-doped (Bi,Sb)2Te3 and GdI2 heterostructure is a quantum anomalous Hall insulator with a band gap up to 38 meV, and the 3D quantum anomalous Hall insulator can be realized in (Bi2/3Cr1/3)2Te3 /GdI2 superlattice. Expected Progress in FY2016 Goldhaber-Gordon will investigate superconducting contacts to QAH systems, measuring supercurrents and magnetic interference patterns in S-QAHE-S Josephson junctions. Goldhaber-Gordon will also use the Oersted fields from currents in nanowires to form magnetic domain boundaries in the bulk of a magnetically-doped TI film (both Cr-BiSbTe and the recently demonstrated V-BiSbTe, which shows QAH at up to 1 Kelvin), and test Zhang’s prediction that these should host 1D chiral conduction channels. Orenstein will spatially map magnetic domains produced in this way. With recently-improved clean QSH edges and nanofabrication on these systems, Goldhaber-Gordon will test Zhang’s theories for backscattering on these edges induced by local potential perturbations. Manoharan and Zhang plan to investigate the vortex state of the proximity coupled system of superconductor with NaCoO2, and measure the tunneling spectrum of the core states, to observe possible signatures of the Majorana bound state at zero energy. Together with Manoharan and Harold Hwang of MSD/SLAC, Orenstein will perform optical measurements on systems with strong spin-orbit coupling, such as BiTeI and the interface of superconductors grown on small gap semiconductors. Goldhaber-Gordon will perform transport measurements on these systems, particularly the semiconducting ones. Manoharan and Zhang will complete the theory investigation to explain experiment results on spin-polarized topological edge states observed in molecular graphene. This will include a theoretical prediction of the conditions necessary for half-metallicity. Orenstein and Zhang plan to investigate the magnetic order in Cr-doped topological insulators, and study the mechanism for ferromagnetism in the insulating regime. Together with Manoharan and Goldhaber-Gordon, Orenstein will perform systematic magneto-optic Kerr measurements on this system. Zhang plans to perform detailed theoretical calculations on the ferromagnetic order and Kerr rotation angle at different chemical potential and compare with the experimental data. Expected Progress in FY2017 Goldhaber-Gordon will explore Majorana states in superconducting contacts to QAH edges. This will likely require development of microwave-frequency conductance measurements, due to short quasiparticle relaxation times. Manoharan will use AFM and STM/STS to investigate these lithographically patterned samples from GoldhaberGordon. Manoharan and Zhang plan to investigate the proximity coupling between superconductors and the quantum anomalous Hall state, and confirm the coupling by measuring the tunneling spectrum. Moreover, Manoharan and Zhang plan to investigate the vortex state of this proximity coupled superconductor, and measure the tunneling spectrum of the core states, to observe possible signatures of the Majorana bound state at zero energy. Goldhaber-Gordon will perform transport measurements on these systems, in order to confirm the chiral topological superconductivity in this system. 29 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Spin Physics Date Submitted: 6/18/2015 FWP#: 10029 SIMES will undergo its triannual DOE program review November 2015. A full narrative of the SIMES FWP program will be available at that time. Collaborations L. Molenkamp (Wuerzburg Germany), K. Wang (UCLA), Q-K Xue (Tsinghua, China), K.He (Tsinghua, China), ChaoXing Liu (Penn State), Rui-Rui Du (Rice), Yulin Chen (Oxford). Publications Peer-Reviewed Journal Articles 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. Jason C. Randel, Francis C. Niestemski, Andrés R. Botello-Mendez, Warren Mar, Georges Ndabashimiye, Sorin Melinte, Jeremy E. P. Dahl, Robert M. K. Carlson, Ekaterina D. Butova, Andrey A. Fokin, Peter R. Schreiner, Jean-Christophe Charlier, and Hari C. Manoharan, Unconventional molecule-resolved current rectification in diamondoid-fullerene hybrids. Nature Communications 5, 4877 (2014). Wang, J., B. Lian, and S.-C. Zhang, Universal scaling of the quantum anomalous Hall plateau transition. Physical Review B, 2014. 89(8): p. 085106. Wang, J., H. Mabuchi, and X.-L. Qi, Calculation of divergent photon absorption in ultrathin films of a topological insulator. Physical Review B, 2013. 88(19): p. 195127. Wang, J., Y. Xu, and S.-C. Zhang, Two-dimensional time-reversal-invariant topological superconductivity in a doped quantum spin-Hall insulator. Physical Review B, 2014. 90(5): p. 054503. Wang, Z. and S.-C. Zhang, Topological Invariants and Ground-State Wave functions of Topological Insulators on a Torus. Physical Review X, 2014. 4(1): p. 011006. Yuan, H., et al., Generation and electric control of spin-valley-coupled circular photogalvanic current in WSe2. Nat Nano, 2014. advance online publication. Yuan, H., et al., Generation and electric control of spin–valley-coupled circular photogalvanic current in WSe2. Nat Nano, 2014. 9(10): p. 851-857. Zhang, H., et al., Topological States in Ferromagnetic CdO/EuO Superlattices and Quantum Wells. Physical Review Letters, 2014. 112(9): p. 096804. Zhang, H., et al., Quantum Spin Hall and Quantum Anomalous Hall States Realized in Junction Quantum Wells. Physical Review Letters, 2014. 112(21): p. 216803. A.J. Bestwick, E.J. Fox, Xufeng Kou, Lei Pan, Kang L. Wang, D. Goldhaber-Gordon, Precise Quantization of the Anomalous Hall Effect near Zero Magnetic Field. Physical Review Letters 114, 187201 (2015). Eric Yue Ma, M. Reyes Calvo, Jing Wang, Biao Lian, Mathias Mühlbauer, Christoph Brüne, Yong-Tao Cui, Keji Lai, Worasom Kundhikanjana, Yongliang Yang, Matthias Baenninger, Markus König, Christopher Ames, Hartmut Buhmann, Philipp Leubner, Laurens W. Molenkamp, Shou-Cheng Zhang, David Goldhaber-Gordon, Michael K. Kelly, and Zhi-Xun Shen. To be published in Nature Communications. [Primary ownership is in another FWP, but Zhang and Goldhaber-Gordon, together with our group members supported on DOE, participated in key ways]. Shreyas Patankar, J. P. Hinton, Joel Griesmar, J. Orenstein, J. S. Dodge, Xufeng Kou, Lei Pan, Kang L. Wang, A. J. Bestwick, E. J. Fox, D. Goldhaber-Gordon, Jing Wang, Shou-Cheng Zhang, Resonant magneto-optic Kerr effect in the magnetic topological insulator Cr:(Sbx,Bi1-x)2Te3, arXiv:1505.00728. P. Giraldo-Gallo, Y. Zhang, C. Parra, H. C. Manoharan, M. R. Beasley, T. H. Geballe, M. J. Kramer, I. R. Fisher, Stripe-like nanoscale structural phase separation and optimal inhomogeneity in superconducting BaPb1−xBixO3. Nature Communications, in review (2015). arXiv:1407.7611. 30 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Clathrin Biotemplating Date Submitted: 6/18/2015 FWP#: 10031 Clathrin Biotemplating Principal Investigators: Sarah Heilshorn, Sebastian Doniach, Nicholas Melosh, Andrew Spakowitz Postdoctoral Scholars and Graduate Students: Nicholas Cordella, Abbygail Foster, Brad Krajina, Yifan Kong, Derek Mendez, Kevin Martinez Raines, and Gundolf Schenk Overview The focus of this multi-disciplinary research program is to characterize and exploit the tailored molecular interactions inherent in biological systems. Such understanding will enable engineering of responsive, biomimetic materials that exhibit self-healing and self-regulating transformations. These materials will lead to fundamentally new designs in biomimetic organic/inorganic devices for energy storage, catalysis, solar cells, and fuel cells. The team integrates a wide range of experimental and theoretical approaches to assemble, characterize, and model dynamic assembly. Our recent collaborative effort has focused on experimental and theoretical insights into the fundamentals of biomimetic self-assembly in two and three dimensions, including the development of an Artificial Clathrin Mimetic system that exhibits many of the properties and behaviors of natural clathrin. Furthermore, we are investigating the effects of local topological transformations on the structure and dynamics of supercoiled DNA in order to develop a DNA-based system with novel nanoscale behavior that can assemble responsive materials. Our team is developing novel synthesis and characterization strategies to enable the creation and analysis of our biomimetic materials, including the development of advanced x-ray characterization techniques for atomic scale resolution of biomaterials with local order but disorder at large length scales. Progress in FY2015 Our FWP has built a platform system that can leverage the insights learned from the clathrin system, but with more control over geometry and more amenable to fabrication of larger yields. In particular, we have created “Artificial Clathrin Mimetics” (ACMs) out of thin metal structures with several of the characteristics of clathrin (3-armed legs, localized binding sites, propensity to attach to 2D interfaces) in order to reproduce the dynamic assembly and sampling behavior of native clathrin. By selective functionalization of the ACM faces, we can order them onto fluid 2D air-water interfaces and manipulate their selfassembly structurally and chemically. These particles have been fabricated as micron-sized structural analogues of clathrin, with their self-assembling behavior visualized by optical microscopy at liquid-air interfaces. This general class of behaviors could recreate one of the most advanced and dynamic processes in biology, and would open up an entirely new, micron scale sampling and assembly method. Theoretical efforts in the project have developed a predictive theoretical model for the structure and dynamics of clathrin to establish responsive nanoscale assemblies. Our modeling of clathrin structural transformations led to new insight into the pivotal role of topological transformations within protein networks in dictating large-scale structural transitions. Our recent work in modeling the bud formation in clathrin was featured on the cover the Soft Matter in January 2015 (see Figure 1). To complement our work on clathrin, we are currently Figure 1: Cover image of our theoretical developing a DNA-based system that utilizes local topological model of clathrin bud formation on a changes to trigger structural transformations. This system will be membrane. used to create novel structures at the nanoscale, and incorporating such structures into 2D membranes and 3D gels will result in materials that exhibit large-scale 31 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Clathrin Biotemplating Date Submitted: 6/18/2015 FWP#: 10031 structural changes in response to local dynamic transformations. Double-stranded DNA behavior is strongly influenced by two topological contributions: twist-induced supercoiling and knotting. We have developed a new approach to modeling proteins and nucleic acids that permits us to predict behavior over a range of length and time scales that were previously inaccessible. Furthermore, our new model permits the efficient evaluation of topological quantities associated with supercoiling and knotting. Our theoretical model shows good agreement with the measured structure of supercoiled DNA from dynamic light scattering, and we are currently preparing a manuscript that elucidates the progression of structural transformations in supercoiled DNA. Expected Progress in FY2016 This FWP has developed theoretical and computational models for clathrin proteins and DNA, both exhibiting complex self-assembly and topological effects in their individual and collective behavior. These models will be combined to establish a predictive model for a biomimetic clathrin system that spontaneously assembles on a bilayer or interface. One of the most exciting goals for the next year is fully recreating the endocytosis ‘sampling’ of extracellular contents that clathrin normally performs in the cell. This would create truly advanced biomimetic behavior that could eventually be leveraged for continuous fluidic monitoring, non-destructive single-cell sampling, and self-healing structures. By changing the shape and functionalization of the ACM particles, we aim to mechanically control the underlying lipid support in a similar way to clathrin. We also aim to use the surface properties of these particles to localize secondary, non-membraneinteracting structures to the membrane-assembling particles. These secondary self-assembled structures would allow us to add additional functionality to the clathrin mimicking particles, and recreate the interesting biophysical functionality. Our efforts in modeling correlated X-ray scattering (CXS) will be used to determine dynamic DNA structural properties ranging from 1 to 100 nanometers. Models are currently being compared with experimental data sets obtained at the free-electron laser at SACLA (Japan). These efforts will be used as a structural characterization of supercoiled DNA, which will aid in the development of DNA-based, responsive materials that utilize local topological changes to elicit large-scale structural changes. Expected Progress in FY2017 We plan to study the effects of topoisomerases on the conformations of DNA plasmids using CXS. This will provide a direct measure of the degree of supercoiling of the DNA as a function of the degree of winding of the DNA by various topoisomerases. We have performed simulations of the CXS expected from DNA and expect to use these as a template for analysis of experimental data acquired in the coming 1-2 yeas. These data will inform our design of a DNA-based material composed of interconnected rings of DNA. Introducing local topological changes of the DNA supercoiling will result in large-scale changes in material shape and rheological properties. SIMES will undergo its triannual DOE program review November 2015. A full narrative of the SIMES FWP program will be available at that time. Collaborations Gyan Bhanot (Rutgers University), Marc Delarue (Institute Pasteur, Paris, France), Henri Orland (CEA, Saclay, France), Alberto Salleo (Stanford University), Jay Schieber (Illinois Institute of Technology), Soichi Wakatsuke (SLAC and Stanford Med School), Peter Zwart (LBNL) Publications Peer-Reviewed Journal Articles - Full DOE Support 1. J. J. VanDersarl, S. Mehraeen, A. P. Schoen, S. C. Heilshorn, A. J. Spakowitz, N. A. Melosh. "Rheology and simulation of 2-dimensional clathrin protein network assembly." Soft Matter, 2014, 10(33): 62196227. 32 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Clathrin Biotemplating Date Submitted: 6/18/2015 FWP#: 10031 2. N. Cordella, T. J. Lampo, S. Mehraeen, A. J. Spakowitz. "Membrane Fluctuations Destabilize Clathrin Protein Lattice Order." Biophysical Journal, 2014, 106(7): 1476-1488. 3. K. N. L. Huggins, A. P. Schoen, M. A. Arunagirinathan, S. C. Heilshorn. "Multi-site functionalization of protein scaffolds for bimetallic nanoparticle templating." Advanced Functional Materials, 2014, 24(48): 7737–7744. 4. N. Cordella, T. Lampo, N. Melosh, A. J. Spakowitz. "Membrane indentation triggers clathrin lattice reorganization and fluidization." Soft Matter, 2015, 11(3): 439-448. Peer-Reviewed Journal Articles - Partial DOE Support 5. D. Mendez, T. J. Lane, J. Sung, J. Sellberg, C. Levard, H. Watkins, A. E. Cohen, M. Soltis, S. Sutton, J. Spudich, V. Pande, D. Ratner, S. Doniach. “Observation of correlated X-ray scattering at atomic resolution.” Phil. Trans. R. Soc. B 2014 369, 20130315, published 9 June 2014. This FWP provided support for data acquisition and analysis by PhD student, Derek Mendez. 33 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Magnetization & Dynamics Date Submitted: 6/18/2015 FWP#: 10067 Magnetization & Dynamics Principal Investigator(s): Hermann Dürr, Katheryn Moler, Joachim Stöhr Staff Scientists: Matthias Hoffmann, John Kirtley, and Alexander Reid Postdoctoral Scholars and Graduate Students: Tyler Chase, Zhao Chen, Patrick Granitzka, Daniel Higley, Konstantin Hirsch, Emmanuelle Jal, TianMin Liu, and Yihua Wang Visiting Scientist: Patrick Granitzka Overview The FWP aims at developing a world leading program to understand and control the nanoscale dynamics of complex magnetic materials using soft x-rays at the Linac Coherent Light Source (LCLS) and the Stanford Synchrotron Radiation Laboratory (SSRL). These activities are complemented by laser and electron beam based studies using intense THz pulses to control spin and charge motion in materials. The program addresses the grand challenge problems of emergence of mesoscale spin & charge order far (or even very far) from equilibrium with the specific goal of impacting information technology, a key area underlying US competitiveness and scientific and technological advances in our modern data centric world. The research thrusts in the FWP focus at developing a microscopic understanding of (1) alloptical magnetic switching in metallic alloys, and (2) electric field driven metal-insulator transitions in strongly correlated materials. (3) It also aims at developing a new generation of non-linear x-ray techniques such as stimulated inelastic x-ray scattering to uniquely probe the electronic and spin interactions in emergent mesoscopic phases. Progress in FY2015 Significant progress has been achieved in all three research thrusts through successful experiments at SSRL, LCLS and other FEL sources. In the following, we outline our progress: We used laser-based THz radiation to drive spin dynamics in a prototypical ferrimagnet DyFeO to prepare for future LCLS beamtime applications [1]. In collaboration with external groups we performed x-ray imaging of Co nanoislands [2] and studied dynamical properties of stripe domain ordering [3]. Using SSRL beamline 13, we have investigated the magnetic domain sizes for the latest generation of magnetic hard disc drives with elastic resonant magnetic scattering. These investigations performed in close collaboration with Hitach (HGST) provide valuable input for tailoring future device generations [4]. We have continued our investigatigation of the insulator-metal transition in strongly correlated oxides. o Using Resonant Inelastic X-ray Scattering (RIXS) at the Swiss Light Source (SLS) we probed the evolution of the electronic excitations across the metal-insulator transition in VO2. In collaboration with theory groups data analysis is currently in progress. o We has performed x-ray spectroscopy of the VO2 insulator-metal transition in thermal equilibrium at ALS revealing that electron correlations are the main driving [5]. o We performed optical pump-probe spectroscopy measuremnts in collaboration with F. Parmigiani to investigate the insulator-metal transition in magnetite [6] In collaboration with M. Guehr, we used VUV radiation form laboratory based high-harmonic sources to study transient gratings generated by optically pumping VO2 across the insulator-metal transition [7-9]. Nonlinear x-ray phenomena relatd to the creation of x-ray transparency of matter by stimulated scattering was investigated theoretically [10]. This provides the basis for the ongoing analysis of LCLS experiemtnts aimed at demonstrating these effects experimentally. We have investigated the magnetic domain sizes written by fs laser illumination of FeCoTb alloys. Such materials display all-optical magnetization reversal. The goal of these studies is to use high-anisotropy for writing nanoscale 34 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Magnetization & Dynamics Date Submitted: 6/18/2015 FWP#: 10067 magnetic domains (‘bits’). The experiments demonstrate that ‘bit’ magnetization can be deterministically reversed by single optical laser pusles [11]. These experiemtns lead the way towards imaging the magnetization reversal during all-optical switching in real time. A beamtime at LCLS towards this goal has been granted in FY2015. Data analysis will extend into FY2016. Using the SSRL beamline 13, we have demonstrated high-resolution imaging of o Transient spin accumulation in non-magnetic Cu layers when current is passed through an adjacent ferromagnetic Co layer [12]. This study opens the dor for direct imaging of spin transport in spintronics which will be one of the focal point in this FWP in 2016 and beyond. o Non-linear magnetic solitons excited via spin transfer torque effects in the vicinity of a magnetic nanocontact [13]. This is the first time that such spin wave excitations have been observed directly and opens up a new field of exploration. o These activities were enabled by systematically imporving the experiemtnal infrastructure at beamine 13 in close collaboration with the beamline scientist (H. Ohldag) [14]. Using the XPP station at LCLS we strated to investigate the so-far unexplored ultrafast lattice dynamics during fs laser heating of ferromagnetic materials. In close collaboration with D. Reis (FWP#`10017/Devereaux) we found coherent strain wave propagation though 20nm Fe flims grown epitaxially onto MgO substrates. The high frequency (up to 3.5THz) is surprising and points towards a required extension of current models of ultrafast electron phonon coupling [15]. We started using fs electron pulses as complementray frobes to hard x-rays from LCLS as probes of lattice dynamics [16]. Commissioning a new ultrafsst electron scattering experiment at SLAC (operated by the SLAC accelerator division, X. Wang) we collaborated with A. Lindenberg (FWP#10017/Devereaux) on first studies on ultrafast lattice dynamics in2D materials [18]. Expected Progress in FY2016 Following the program renewal in 2015 the FWP will continue the successful activities described above. In addition more focus will be put (in collaboration with D. Reis) to the use of hard x-rays from LCLS to also probe ultrafast phonon excitations during fs laser heating of magnetic materials. This will be strengthened by including the use of complementary ultrafast electron scattering probes (developed and operated within the SLAC accelerator division, lead: X. Wang). It is suggested to do this in a cost neutral way by curtailing present activities using laboratory-based magnetic imaging techniques (K. Moler). The research thrusts in the FWP will continue to build on the successful FY2015 efforts and will include further scientific challenges identified at a 2015 DOE DMSE workshop on “Static and Dynamic Interface Effects in Magnetism”. In FY 2016 and beyond our goals are to develop a microscopic understanding of (1) all-optical magnetic switching in metallic alloys and heterostructures, and (2) the current-driven spin dynamics at magnetic interfaces. We finally aim at addressing the question (3) How is angular momentum conserved far from equilibrium? We will use soft x-rays form LCLS and SSRL to address (1) and (2). (3) will be addressed using the emerging ultrafast x-ray and electron scattering probes of lattice dynamics. This should allow us to finally address a question at the heart of ultrafast magnetism that has remained unanswered since its inception 20 years ago. Expected Progress in FY2017 Activities at LCLS aiming at all-optical magnetic switching will continue and we will increasingly use electron diffraction as a complementary tool compared to hard x-rays from LCLS. We will use higher spatial resoliution becoming available at SSRL for spin transport studies. Synchrotron and laser based charaterization of new materials and nanostructures will continue hopefully culminating in further high-profile applications for LCLS beamtime. Collaborations Bert Hecht (Wuerzburg Germany), Theo Rasing (Radboud University Nijmegen, NL), Mark Golden (University of Amsterdam, NL), Andy Kent (Columbia University), Stuart Parkin (IBM Almaden), Olav Hellwig (HGST), Keith Nelson (MIT), Rick Averitt (Boston Univiersity), Heidan Wen, John Freeland (APS, Argonne Nat. Lab.), Christian 35 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Magnetization & Dynamics Date Submitted: 6/18/2015 FWP#: 10067 Schüssler-Langeheine (HZ Berlin, Germany, A. Scherz (XFEL, Germany), C. Back (U. Regensburg, Germany), E. Fullerton (UCSD), F. Parmigiani (Trieste, Italy). SIMES will undergo its triannual DOE program review November 2015. A full narrative of the SIMES FWP program will be available at that time. Publications Peer-Reviewed Journal Articles 1. Terahertz-driven magnetism dynamics in DyFeO3, A. H. M. Reid, A. V. Kimel, Th. Rasing, R. V. Pisarev, H. A. Dürr, M. C. Hoffmann, Appl. Phys. Lett. 106, 082403 (2015). 2. Spin reorientation and large magnetic anisotropy of metastable body-centered-cubic Co islands on Au(001), T. Miyamachi, T. Kawagoe, S. Imada, M. Tsunekawa, H. Fujiwara, M. Geshi, A. Sekiyama, K. Fukumoto, F. H. Chang, H. J. Lin, F. Kronast, H. Dürr, C. T. Chen, S. Suga, Phys. Rev. B 90, 174410 (2014). 3. Irreversible transformation of ferromagnetic ordered stripe domains in single-shot infrared-pump/resonantx-ray-scattering-probe experiments, Nicolas Bergeard, Stefan Schaffert, Victor Lopez-Flores, Nicolas Jaouen, Jan Geilhufe, Christian M. Günther, Michael Schneider, Catherine Graves, Tianhan Wang, Benny Wu, Andreas Scherz, Cedric Baumier, Renaud Delaunay, Franck Fortuna, Marina Tortarolo, Bharati Tudu, Oleg Krupin, Michael P. Minitti, Joe Robinson, William F. Schlotter, Joshua J. Turner, Jan Lüning, Stefan Eisebitt, Christine Boeglin, Phys. Rev. B 91, 054416 (2015) . 4. Extracting magnetic cluster size and its distributions in advanced perpendicular recording media with shrinking grain size using small angle x-ray scattering, Virat Mehta, Tianhan Wang, Yoshihiro Ikeda, Ken Takano, Bruce D. Terris, Benny Wu, Catherine Graves, Hermann A. Dürr, Andreas Scherz, Jo Stöhr and Olav Hellwig, App. Phys. Lett. 106, 202403 (2015). 5. Correlation-driven insulator-metal transition in near-ideal vanadium dioxide films, A. X. Gray, J. Jeong, N. P. Aetukuri, P. Granitzka, Z. Chen, R. Kukreja, D. Higley, T. Chase, A. H. Reid, H. Ohldag, M. Marcus, A. Scholl, A. T. Young, A. Doran, C. A. Jenkins, P. Shafer, E. Arenholz, M. G. Samant, S. S. P. Parkin, H. A. Dürr, Phys. Rev. Lett. submitted (2015) arXiv:1503.07892 6. Signature of the phase separation in the non-equilibrium Verwey transition in magnetite, F. Randi, I. Vergara Kausel, F. Novelli, M. Esposito, M. Dell’Angela, C. Schüßler-Langeheine, P. Metcalf, R. Kukreja, H. Dürr, M. Grüninger, D. Fausti, F. Parmigiani, Phys. Rev. B submitted (2015). 7. Broadband extreme ultraviolet probing of transient gratings in vanadium dioxide, Emily Sistrunk, Jakob Grilj, Jaewoo Jeong, Mahesh G. Samant, Alexander X. Gray, Hermann A. Dürr, Stuart S. P. Parkin, Markus Gühr, Optics Express 23, 4340 (2015). 8. Extreme Ultraviolet Transient Grating Measurement of Insulator-Metal Transition Dynamics in VO2, Emily Sistrunk, Jakob Grilj, Jaewoo Jeong, Mahesh G. Samant, Alexander X. Gray, Hermann A. Dürr, Stuart S. P. Parkin, Markus Gühr, Ultrafast Phenomena XIX, Springer Proceedings in Physics Volume 162, 64 (2015). 9. Self referencing heterodyne transient grating spectroscopy with short wavelength, Jakob Grilj, Emily Sistrunk, Jaewoo Jeong, Mahesh G. Samant, Alexander X. Gray, Hermann A. Dürr, Stuart S. P. Parkin, Markus Gühr, Photonics 2, 392-401 (2015). 10. Creation of X-Ray Transparency of Matter by Stimulated Elastic Forward Scattering, J. Stöhr, A. Scherz, Phys. Rev. Lett. submitted (2015). 11. Nanoscale confinement of all-optical magnetic switching in TbFeCo – competition with nanoscale heterogeneity, TianMin Liu, Tianhan Wang, Alexander H. Reid, Matteo Savoini, Xiaofei Wu, Benny Koene, Patrick Granitzka, Catherine Graves, Daniel Higley, Zhao Chen, Gary Razinskas, Markus Hantschmann, Andreas Scherz, Joachim Stöhr, Arata Tsukamoto, Bert Hecht, Alexey V. Kimel, Andrei Kirilyuk, Theo Rasing, Hermann A. Dürr, submitted (2015) arXiv:1409.1280. 12. X-Ray Detection of Transient Spin Accumulation on Cu atoms near a Co/Cu Interface, R. Kukreja, S. Bonetti, Z. Chen, D. Backes, Y. Acremann, J. Katine, A.D. Kent, H. A. Dürr, H. Ohldag, J. Stöhr, Phys. Rev. Lett. submitted (2015) arXiv:1503.07275. 36 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Magnetization & Dynamics Date Submitted: 6/18/2015 FWP#: 10067 13. Direct observation and imaging of a spin-wave soliton with p−like symmetry, S. Bonetti, R. Kukreja, Z. Chen, F. Macia, J. M. Hernandez, A. Eklund, D. Backes, J. Frisch, J. Katine, G. Malm, S. Urazhdin, A. D. Kent, J. Stöhr, H. Ohldag, H. A. Dürr, submitted (2015) arXiv:1504.00144. 14. Microwave soft x-ray microscopy for nanoscale magnetization dynamics in the 5–10 GHz frequency range, Stefano Bonetti, Roopali Kukreja, Zhao Chen, Detlef Spoddig, Katharina Ollefs, Christian Schöppner, Ralf Meckenstock, Andreas Ney, Jude Pinto, Richard Houanche, Josef Frisch, Joachim Stöhr, Hermann Dürr, Hendrik Ohldag, submitted (2015) arXiv:1504.07561. 15. Generation of high-frequency strain waves during femtosecond demagnetization of Fe/MgO(001) films, T. Henighan, S. Bonetti, P. Granitzka, M. Trigo, Z. Chen, R. Kukreja, D. Higley, A. Gray, A. H. Reid, E. Jal, M. Hoffmann, M.E. Kozina, S. Song, M. Collet, D. Zhu, J. Jeong, M. G. Samant, S. S. P. Parkin, D.A. Reis, H. A. Dürr, in preparation (2015). 16. The future of electron microscopy, Yimei Zhu, Hermann Dürr, Physics Today 68, 32 (2015). 17. MeV Ultrafast Electron Diffraction at SLAC, S. P. Weathersby, G. Brown, M. Centurion, T. F. Chase, R. Coffee, J. Corbett, J. P. Eichner, J. C. Frisch, A. R. Fry, M. Gühr, N. Hartmann, C. Hast, R. Hettel, R. K. Jobe, E. N. Jongewaard, J. R. Lewandowski, R. K. Li, A. M. Lindenberg, I. Makasyuk, J. E. May, D. McCormick, M. N. Nguyen, A. H. Reid, X. Shen, K. Sokolowski-Tinten, T. Vecchione, S. L. Vetter, J. Wu, J. Yang, H. A. Dürr, X. J. Wang, submitted (2015). 18. Dynamic structural response and deformations of monolayer MoS2 visualized by femtosecond electron Diffraction, Ehren M. Mannebach, Renkai Li, Karel-Alexander Duerloo, Clara Nyby, Peter Zalden, Theodore Vecchione, Friederike Ernst, Alexander Hume Reid, Tyler Chase, Xiaozhe Shen, Stephen Weathersby, Carsten Hast, Robert Hettel, Ryan Coffee, Nick Hartmann, Alan R. Fry, Yifei Yu, Linyou Cao, Tony Heinz, Evan J. Reed, Hermann A. Dürr, Xijie Wang, Aaron M. Lindenberg, submitted (2015). 37 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Atomic Engineering Oxide Heterostructures: Materials by Design Date Submitted: 6/18/2015 FWP#: 10069 Atomic Engineering Oxide Heterostructures: Materials by Design Principal Investigator(s): Harold Y. Hwang (FWP lead), Srinivas Raghu, Yasuyuki Hikita Staff Scientists: Jun-Sik Lee, Yanwu Xie, Hongtao Yuan Postdoctoral Scholars and Graduate Students: Zhuoyu Chen, Samuel Crossley, Yaron Gross, Seung Sae Hong, Pavan Hosur, Hisashi Inoue, Rea Kolbl, Di Lu, Akash Maharaj, Tyler Merz, Kazunori Nishio, and Hyeok Yoon Visiting Physicists: Takashi Tachikawa Overview The overarching scientific goals of this FWP are to use techniques we have developed for atomic-scale synthesis of complex oxide heterostructures to address the grand challenges for basic energy sciences. The issues we investigate are central to the challenge of “how do we atomically design and perfect revolutionary new forms of matter with tailored properties”, and which are also important to the challenges of controlling processes at the electron level, understanding and creating emergent phenomena, and mastering energy and information on the nanoscale. Keywords for this FWP are emergence, design, and engineering: Emergence – how can we harness the strongly interacting charge, spin, orbital, and lattice degrees of freedom of transition metal oxides to create new states at their surfaces and interfaces, which exhibit properties beyond their bulk constituents? Design – how can we use theory to transcend intuition and serendipity, and move towards the rational construction of materials at the atomic scale? Engineering – how can we use the flexibility and reduced symmetry of oxide interfaces and surfaces to enhance their properties and band lineups for optimal use in energy technologies? X-ray scattering, spectroscopy, and microscopy are used to examine the surface and interface electronic structure, their nanoscale coupling, and their lateral nanoscale static and dynamic order. Magnetotransport and scanning probes are used to study artificial two-dimensional (2D) superconducting and magnetic oxide heterostructures, towards the development of the mesoscopic physics of d-electron systems. Advanced analytical and computational theory techniques are applied to develop a quantitative foundation for analysis and predictive design. In addition to the core mission of DoE BES, these aims are well aligned to the Materials Genome Initiative, and the Mesoscale Materials and Chemistry Initiative currently being developed. Progress in FY2015 We have suggested a set of transport measurements that can be used to detect spontaneous mirror symmetry breaking in correlated electron materials. The idea is to measure longitudinal resistivity in the presence of shear strain, or to measure the Hall resistivity in the presence of uniaxial strain. Neither response is finite when certain mirror planes are present in the system. We suggested that several candidate phases for the pseudogap regime of hole-doped cuprate materials would exhibit a finite value of such response functions and made concrete estimates for several distinct experimental protocols. We have studied quantum oscillations signatures of charge ordering in cuprate superconductors. We are in the process of studying quantum oscillations in oxide interfaces to deduce the form and magnitude of spin-orbit coupling present in these interfaces. We have developed dual gate structures which can independently modulate the mobility and carrier density in superconducting oxide heterointerfaces, using a hybrid ionic-liquid/solid gate technique. We have constructed a simple theory for the non-monotonic variation of Tc as a function of electron concentration in 3D strontium titanate. The theory invokes the proximity to the BEC-BCS crossover. We are currently contrasting the results for the 3D bulk and the 2D interfaces in comparison with experiments. 38 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Atomic Engineering Oxide Heterostructures: Materials by Design Date Submitted: 6/18/2015 FWP#: 10069 We are considering scaling theories of electrons in 2D in the presence of both interactions and disorder. We are studying the effect of correlated disorder and Coulomb interactions in a 2DEG and have found new renormalization group fixed point descriptions of electron systems which are metallic, and occur only in the presence of both disorder and Coulomb interactions. We are applying our theory to the phenomenology of the superconductorinsulator transition, as well as the closely related problem of quantum Hall plateau transitions. We showed using a very simple effective theory how superconductivity can be singularly enhanced at a Pomeranchuk instability, provided that the Pomeranchuk transition is continuous. Another effect is that near such transitions, Landau Fermi liquid behavior is destroyed. We have studied regimes where the enhancement of superconductivity dominates over the destruction of Fermi liquid behavior and vive versa. We have studied ultrathin oxide films via transport and resonant x-ray scattering, demonstrating a novel 1D electronic/magnetic reconstruction at the atomic scale step edges of the films. Expected Progress in FY2016 We are studying electrons tuned to van Hove singularities in 2D. Such systems allegedly exhibit higher temperature superconductivity as well as competition to other broken symmetry phases, including magnetism and nematic order. We are constructing a new scaling theory of such instabilities based on our studies of non-Fermi liquid behavior near quantum critical points. Experiments are currently underway to study monolayer films of electronic materials tuned via strain across the van Hove singularity. We are combining transport with x-ray spectroscopy to examine the evolution of the electronic structure in oxide films gated via solid and ionic-liquid structures. We are studying the superconducting properties of quasi-one dimensional systems. We are studying instabilities to triplet superconductivity, as well as the crossover from Luttinger liquid behavior at high temperatures to Fermi liquid behavior at low temperature. Expected Progress in FY2017 Further theoretical study of strongly enhanced superconducting instabilities near quantum critical points, the goal being to identify limits where higher Tc superconductivity can emerge from a non-Fermi liquid regime, the parametric enhancement of Tc and the effect of quantum critical fluctuations on the superfluid density. Further x-ray probes of magnetic reconstructions in ultrathin magnetic oxide films are planned, first to examine static properties, and eventually dynamical response. Increasing efforts to study magnetotransport in oxides on mesoscopic length scales are planned, as well as the development and utilization of inelastic tunneling spectroscopy. SIMES will undergo its triannual DOE program review November 2015. A full narrative of the SIMES FWP program will be available at that time. Collaborations T.H. Geballe, S. Kachru, A. Kapitulnik, S. Kivelson, K. A. Moler, Y. Cui, T. P. Devereaux, Z. X. Shen, H. Durr, J. Stohr, J. K. Norskov, A. Nilsson, M. Brongersma, C.-C. Kao, X. Qi (Stanford/SLAC); R. Thomale (ETF Lausanne); H. Akiyama, A. Fujimori, Y. Iwasa, M. Kawasaki, K. Miyano, N. Nagaosa, M. Oshima, S. Shin, H. Takagi, Y. Tokura (Tokyo); T. Kimura, Y. Wakabayashi (Osaka); H. Ohta (Nagoya); T. Egami, H. N. Lee (ORNL); J. Levy (Pittsburgh); Y. Taguchi (RIKEN); D. A. Muller, L. F. Kourkoutis, D. G. Schlom (Cornell); B. G. Kim (Pusan); B. Keimer, J. Mannhart (MPI Stuttgart); T. W. Noh (Seoul); C. Bernard (Fribourg); D. H. A. Blank, G. Rijnders (Twente); R. Ramesh (Berkeley); J. H. Song (Chungnam); A. F. Hebard (Florida); G. A. Sawatzky (UBC); T. Banerjee (Groningen); A. J. Millis (Columbia); F. Baumberger, J. M. Triscone (Geneva); S. J. Allen, D. D. Awschalom, C. Nayak, S. Stemmer, C. Van de Walle (UCSB); S. Rajan (Ohio State); D. Jena (Notre Dame); C. H. Ahn, T. P. Ma (Yale); Y. Dagan (Tel Aviv); J. Aarts, Y. M. Huber (Leiden); C. Attanasio (CNR-INFM); M. G. Blamire (Cambridge); B. Kalisky (Bar-Ilan); H. Kumigashira (KEK, Japan); M. Yu. Kupriyanov (Moscow State); V. N. Kushnir (Belarus State); W. Meevasana (Thailand Center of Excellence in Physics); R. J. Wijngaarden (Vrije). 39 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Atomic Engineering Oxide Heterostructures: Materials by Design Date Submitted: 6/18/2015 FWP#: 10069 Publications Peer-Reviewed Journal Articles 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. J. A. Mundy, Y. Hikita, T. Hidaka, T. Yajima, T. Higuchi, H. Y. Hwang, D. A. Muller, and L. F. Kourkoutis, “Visualizing the Interfacial Evolution from Charge Compensation to Metallic Screening across the Manganite Metal-Insulator Transition,” Nature Communications 5, 3464:1-6 (2014). A. L. Fitzpatrick, S. Kachru, J. Kaplan, and S. Raghu, “Non-Fermi Liquid Behavior of Large N_B Quantum Critical Metals,” Physical Review B 89, 165114 (2014). S. Lederer, W. Huang, E. Taylor, S. Raghu, and C. Kallin, “Suppression of Spontaneous Currents in Sr2RuO4 by Surface Disorder,” Physical Review B 90, 134521 (2014). H. Watanabe, S. Parameswaran, S. Raghu, and A. Vishwanath, “Anomalous Fermi Liquid Phase in Metallic Skyrmion Crystals,” Physical Review B 90, 045145 (2014). Y. W. Xie, C. Bell, M. Kim, H. Inoue, Y. Hikita, and H. Y. Hwang, “Quantum Longitudinal and Hall Transport at the LaAlO3/SrTiO3 Interface,” Solid State Communications 197, 25-29 (2014). M. Minohara, T. Tachikawa, Y. Nakanishi, Y. Hikita, L. Fitting Kourkoutis, J.-S. Lee, C.-C. Kao, M. Yoshita, H. Akiyama, C. Bell, and H. Y. Hwang, “Atomically Engineered Metal-Insulator Transition at the TiO2/LaAlO3 Heterointerface,” Nano Letters 14, 6743-6746 (2014). A. Maharaj, P. Hosur, and S. Raghu, “Criss-Crossed Stripe Order from Interlayer Tunneling in Hole-doped Cuprates,” Physical Review B 90, 125108 (2014). Y. Yamada, H. K. Sato, Y. Hikita, H. Y. Hwang, and Y. Kanemitsu, “Photocarrier Recombination and Localization Dynamics of LaAlO3/SrTiO3 Heterostructures,” Proceedings of the SPIE 8987, 898710:1-7 (2014). Y. Takahashi, S. Chakraverty, M. Kawasaki, H. Y. Hwang, and Y. Tokura, “In-plane Terahertz Response of Thin Film Sr2RuO4,” Physical Review B 89, 165116:1-5 (2014). Y. Yamada, H. K. Sato, Y. Hikita, H. Y. Hwang, and Y. Kanemitsu, “Spatial Density Profile of Electrons Near the LaAlO3/SrTiO3 Heterointerface Revealed by Time-Resolved Photoluminescence Spectroscopy,” Applied Physics Letters 104, 151907:1-4 (2014). A. G. Swartz, S. Harashima, Y. W. Xie, D. Lu, B. J. Kim, C. Bell, Y. Hikita, and H. Y. Hwang, “Spin Dependent Transport Across Co/LaAlO3/SrTiO3 Heterojunctions,” Applied Physics Letters 105, 032406:1-4 (2014). Y. Lei, Y. Z. Chen, Y. W. Xie, S. H. Wang, Y. Li, J. Wang, B. G. Shen, N. Pryds, H. Y. Hwang, and J. R. Sun, “Visible Light Enhanced Field Effect at the LaAlO3/SrTiO3 Interface,” Nature Communications 5, 5554:1-5 (2014). H. T. Yuan, X. Q. Wang, B. Lian, H. Zhang, X. Fang, B. Shen, G. Xu, Y. Xu, S. C. Zhang, H. Y. Hwang, and Y. Cui, “Generation and Electric Control of Spin-Valley-Coupled Circular Photogalvanic Current in WSe2,” Nature Nanotechnology 9, 851-857 (2014). X. Liu, J.-H. Park, J.-H. Kang, H. T. Yuan, Y. Cui, H. Y. Hwang, and Mark L. Brongersma, “Quantification and Impact of Nonparabolicity of the Conduction Band of Indium Tin Oxide on its Plasmonic Properties,” Applied Physics Letters 105, 181117:1-4 (2014). T. Yajima, M. Minohara, C. Bell, H. Kumigashira, M. Oshima, H. Y. Hwang, and Y. Hikita, “Enhanced Electrical Transparency by Ultra-Thin LaAlO3 Insertion at Oxide Metal/Semiconductor Heterointerfaces,” Nano Letters 15, 1622-1626 (2015). T. Yajima, Y. Hikita, M. Minohara, C. Bell, J. A. Mundy, L. F. Kourkoutis, D. A. Muller, H. Kumigashira, M. Oshima, and H. Y. Hwang, “Controlling Band Alignments by Artificial Interface Dipoles at Perovskite Heterointerfaces,” Nature Communications 6, 6759:1-5 (2015). Z. Erlich, Y. Frenkel, J. Drori, Y. Shperber, C. Bell, H. K. Sato, M. Hosoda, Y. W. Xie, Y. Hikita, H. Y. Hwang, and B. Kalisky, “Optical Study of Tetragonal Domains in LaAlO3/SrTiO3,” Journal of Superconductivity and Novel Magnetism 28, 1017-1020 (2015). V. Thareja, J. Kang, H. T. Yuan, K. M. Milaninia, H. Y. Hwang, Y. Cui, P. G. Kik, and M. L. Brongersma, “Electrically Tunable Coherent Optical Absorption in Graphene with Ion Gel,” Nano Letters 15, 1570-1576 (2015). T. Tsuyama, T. Matsuda, S. Chakraverty, J. Okamoto, E. Ikenaga, A. Tanaka, T. Mizokawa, H. Y. Hwang, Y. Tokura, and H. Wadati, “X-Ray Spectroscopic Study of BaFeO3 Thin Films: An Fe4+ Ferromagnetic Insulator,” Physical Review B 91, 115101:1-7 (2015). S. C. Riggs, M. C. Shapiro, A. V. Maharaj, S. Raghu, E. D. Bauer, R. E. Baumbach, P. Giraldo-Gallo, M. Wartenbe, and I. R. Fisher, “Evidence for a Nematic Component to the Hidden-Order Parameter in URu2Si2 from Differential Elastoresistance Measurements,” Nature Communications 6, 6425 (2015). P. Munkhbaatar, Z. Marton, B. Tsermaa, W. S. Choi, S. S. A. Seo, J. S. Kim, N. Nakagawa, H. Y. Hwang, H. N. Lee, and K. Myung-Whun, “Room Temperature Optical Anisotropy of a LaMnO3 Thin-film Induced by Ultra-short Pulse Laser,” Applied Physics Letters 106, 092907:1-4 (2015). 40 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Two-Dimensional Chalcogenide Nanomaterials Date Submitted: 6/18/2015 FWP#: 100141 Two-Dimensional Chalcogenide Nanomaterials Principal Investigator(s): Yi Cui (FWP lead), Harold Y. Hwang, Shoucheng Zhang, Jun-Sik Lee Staff Scientists: Yasuyuki Hikita, Hongtao Yuan Postdoctoral Scholars and Graduate Students: Wei Chen, Di Lu, Jie Sun, Chun Lan Wu, Gang Xu, Jung Ho Yu, Jinsong Zhang Visiting Physicists: Shougo Higashi, Alex Welch Overview Our long-term vision is to build a cutting-edge research program developing an exciting class of two dimensional (2D) chalcogenide (O, S, Se, Te) nanomaterials, which can generate high impact on a wide range of DoE BES priorities in materials design and control. Our central focus is understanding and utilizing the modification of the physical properties of these materials by their heterogeneous ionic environment. Here this ionic environment is realized through synthesis of heterostructured interfaces, electric double layer gating, electrochemical intercalation and chemical tuning. Based on the past excellent research accomplishments in this area, the co-PI’s (Yi Cui, Harold Hwang, Jun-Sik Lee and Shoucheng Zhang) integrate their research activity synergistically to explore an exciting territory of 2D nanomaterials discovery, computational design, synthesis and novel properties. To reach this long-term vision, this proposal outlines three thrusts of research to be conducted within the next three years: Thrust 1. Design and synthesis of novel 2D nanomaterials focusing on interfaces between different ionic environments. Thrust 2. Ionic tuning of 2D nanomaterials by electric double layer gating, electrochemical interaction and chemical tuning. Thrust 3. Probe and manipulate the exciting electronic and photonic properties of these novel materials. This proposal well matches the priorities of DoE BES and the development plan for the Stanford Institute for Materials and Energy Sciences (SIMES), the Materials Sciences Division at SLAC. It also integrates four co-located leading scientists with materials, theory, and X-ray expertise into a team to address this timely research opportunity, via this FWP on 2D chalcogenide nanomaterials. Progress in FY2015 We have successfully demonstrated the generation and further electrical control of a spin-coupled valley photocurrent, within an electric-double-layer transistor based on WSe2, whose direction and magnitude depend on the degree of circular polarisation of the incident radiation and can be further modulated with an external electric field. This room temperature generation and electric control of valley and spin photocurrent provides a new property of electrons in transition-metal dichalcogenides systems, thereby enabling new degrees of control for quantum-confined spintronic devices. We have demonstrate a broadband photodetector using layered black phosphorus transistors which is polarisation sensitive over a broad bandwidth from about 400 nm to 3750 nm. The polarisation‐ sensitivity is due to the strong intrinsic linear dichroism, which arises from the in‐plane optical anisotropyofthismaterial.Inthistransistorgeometry,aperpendicularbuilt‐inelectricfieldinducedby gatingcanspatiallyseparatethephoto‐generatedelectronsandholesinthechannel,effectivelyreducing theirrecombinationrate,andthusenhancingtheperformanceforlineardichroismphotodetection. We demonstrated atomically thin rhenium disulfide (ReS2) flakes with a unique distorted 1T structure, which exhibit in-plane anisotropic properties that are induced by low lattice symmetry. We fabricated mono- and fewlayer ReS2 field effect transistors (FETs), which exhibit competitive performance with large current on/off ratios (~108) and low subthreshold swings (100 mV/dec) at room temperature. The observed anisotropic ratio 41 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Two-Dimensional Chalcogenide Nanomaterials Date Submitted: 6/18/2015 FWP#: 100141 along the two principle axes reaches 3.1, which is the highest among all known 2D semiconducting materials. Furthermore, we successfully demonstrated an integrated digital inverter with good performance by utilizing two ReS2 anisotropic FETs, suggesting the promising implementation of large-scale 2D logic circuits. Our results underscore the unique properties of 2D semiconducting materials with low crystal symmetry, which can be exploited for future novel electronic applications. We discovered extraordinary light transmission through thin nanoplates of layered bismuth chalcogenides bychemical intercalation of copper atoms, which is on the contrary to most bulk materials in which doping reduces the light transmission. We discover substantial enhancement of light transmission and electrical conductivity in ultrathin MoS2 nanosheets after Li intercalation, due to changes in band structure that reduce absorption upon intercalation and the injection of large amounts of free carriers. This dynamic tuning capability via intercalation shows great potential in many applications. We also capture the first in-situ optical observations of Li intercalation in MoS2 nanosheets, shedding lights on the dynamics of the intercalation process and the associated spatial inhomogeneity and cycling-induced structural defects. We examined the impact of intercalated lithium (Li) ions on the thermal properties of thin films of MoS2 down to the order of tens of nanometers in thickness. We use in-situ time-domain thermoreflectance (TDTR) to monitor changes in the thermal conductivity of MoS2 films (kMoS2) while simultaneously performing intercalation and de-intercalation of Li+ ions. Changes in kMoS2 are dynamically measured by recording changes in the ratio of the in-phase to out-of-phase voltage components of the reflected probe intensity at fixed, short delay times. This ability to reversibly tune thermal conductivity via electrochemical modulation at the nanoscale could enable new applications in energy conversion and thermal management, where the dynamic control of heat transfer is a potentially useful feature. We investigated the insulator-metal phase transition behavior of layered 2H-MoSe2 using pressure generated by a Diamond Anvil Cell. We found that pressure allows MoSe2 to change from a highly anisotropic 2D layered network to an isotropic 3D solid where the van der Waals gap is effectively closed. With continuous contractions in lattice parameters under pressure, MoSe2 evolves from a semiconductor to a metal with the “indirect” feature of its band structure being well preserved. Our results underscore pressure’s role in tuning the mechanical, optical, and electronic properties of layered transition metal dichalcogenides. We have successfully developed the synthesis and structural characterization of a family of 2D-layered metal dichalcogenide films (MoS2, MoSe2, WS2, WSe2) whose crystal layers are perpendicular the the substrate surface. We have measured the catalytic activity of hydrogen evolution of vertically aligned 2D-layered dichalcoenide films. We showed that the edge exposure of this structure affords high activity of hydrogen evolution and also present well-defined sample for quantifiying catalytically active sites. We demonstrated the synthesis of vertical heterostructure of n-type MoS2 and p-type WSe2 with vertically aligned atomic layers. The heterostructure synthesis is scalable to a large area over 1 cm2. We demonstrated the pn junction diode behavior of the heterostructure device. This novel device geometry opens up exciting opportunities for a variety of electronic and optoelectronic devices, complementary to the recent interesting vertical heterostructures with horizontal atomic layers. We explored the use of black phosphorus (BP) as an anode material for SIB and found the two-step reaction mechanism of ‘intercalation’ and ‘alloying’. BP exhibits a high capacity (~2300 mA h g-1) upon its sodiation to Na3P, even though the large anisotropic expansion occurs upon alloy reaction resulting in the main limitation to utilize its full reversible capacity. In order to overcome this issue, we designed a new, sandwiched phosphorenegraphene structure. This newly developed material shows outstanding electrochemical properties with a high specific capacity of 2440 mA h g-1 (calculated using P mass only) at a current densitiy of 0.05 A/g and an 83 % capacity retention after 100 cycles. Expected Progress in FY2016 Further experiments on growing intrisinc and doped layered materials including the magnetic-atom doping or interrelation and copper into layer materials or strontium doping for topological superconductors. Demonstrationg of electrochemical and strain tuning of layered materials for electrocatalysis. Further demonstration of the chemical and electrochemical tuning of layered materials on the electronic, spintronic and optical properties. Further research on electric double layer gating on 2D materials and field-induced superconductivity. Further experiments to use 42 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Two-Dimensional Chalcogenide Nanomaterials Date Submitted: 6/18/2015 FWP#: 100141 intercalation to tune 2D material electrical, thermal and thermoelectric (Seebeck coefficient) properties to enhance the ZT for more efficient thermoelectric harvesting. Expected Progress in FY2017 Further study on electrocatalysis with 2D materials and experimental chemical and electrochemical tuning. Theorectical and simulation understanding of the effect of chemical and electrochemical tuning on the electronic structure. ARPES study of electronic structure of 2D materials. Further demonstrationof the chemical and electrochemical tuning of layered materials on the electronic, spintronic and optical properties. Further research on electric double layer gating on 2D materials and field-induced superconductivity. Collaborations S. Fan (Stanford), M. Brongersma (Stanford), Wendy L. Mao (Stanford), Y. L. Chen (Oxford), Z. X. Shen (Stanford). Publications 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. H. T. Yuan, X. G. Liu, F. Afshinmanesh, W. Li, G. Xu, J. Sun, B. Lian, G. J. Ye, Y. Hikita, Z. X. Shen, S.-C. Zhang, X. H. Chen, M. Brongersma, H. Y. Hwang, Y. Cui, Broadband linear-dichroic photodetector in a black phosphorus vertical p-n junction. Nature Nanotechnology (2015) DOI: 10.1038/NNANO.2015.112. H. T. Yuan, X. Q. Wang, B. Lian, H. J. Zhang, X. F. Fang, B. Shen, G. Xu, Y. Xu, S.-C. Zhang, H. Y. Hwang and Y. Cui, Generation and electric control of spin-coupled valley current in WSe2. Nature Nanotechnology 9, 851–857 (2014). H. T. Yuan, H. T. Wang, Y. Cui, Two-dimensional layered nanomaterials: toward property control via orbital occupation and electron filling. Accounts of Chemical Research 48, 81-90 (2015). H. T. Wang, H. T. Yuan, S. S. Hong, Y.B. Li, Y. Cui, Physical and chemical strategies for tuning twodimensional transition metal dichalcogenides properties. Chemical Society Reviews (2015) DOI: 10.1039/C4CS00287C. Z. Zhao, H. J. Zhang, H. T. Yuan, S. B. Wang, Y. Lin, Q. S. Zeng, Z. Liu, K. D. Patel, G. K. Solanki, Y. Cui, H. Y. Hwang, W. L. Mao. Pressure tuning the crystal structure and electronic state of MoSe2. Nature Communications (2015) in press. E. Liu, Y. Fu, Y. Wang, Y. Feng, Y. Pan, H. Liu, X. Wan, W. Zhou, B. Wang, Z. Cao, L. Wang, A. Li, J. Zeng, F. Song, X. Wang, Y. Shi, H. T. Yuan, H. Y. Hwang, Y. Cui, F. Miao & D. Xing. Rhenium disulphide anisotropic field-effect transistors and digital inverters. Nature Communications (2015) in press. S. S. Hong, D. Kong, and Y. Cui, Topological insulator nanostructures, MRS Bulletin 39, 873 (2014) J. Yao, K. J. Koski, W. Luo, J. J. Cha, L. Hu, D. Kong, V. K. Narasimhan, K. Huo, and Y. Cui, Optical transmission enhancement through chemically tuned two-dimensional bismuth chalcogenide nanoplates, Nature Communications 5, 5670 (2014). H. Wang, Q. Zhang, H. Yao, Z. Liang, H.-W. Lee, P.-C. Hsu, G. Zheng, and Y. Cui, High Electrochemical Selectivity of Edge versus Terrace Sites in Two-Dimensional Layered MoS2 Materials, Nano Letters (2014) DOI:10.1021/NL503730C. J. H. Yu, H. R. Lee, S. S. Hong, D. Kong, H.-W. Lee, H. Wang, F. Xiong, S. Wang, and Y. Cui, Vertical Heterostructure of Two-Dimensional MoS2 and WSe2 with Vertically Aligned Layers, Nano Letters (2015) DOI:10.1021/NL503897H. H. Wang, C. Tsai, D. Kong, K. Chan, F. Abild-Pedersen, J. K. Norskov, and Y. Cui, Transition-metal Doped Edge Sites in Vertically Aligned MoS2 Catalysts for Enhanced Hydrogen Evolution, Nano Research (2015) DOI:10.1007/S12274-014-0677-7. S. S. Hong, Y. Zhang, J. J. Cha, X.-L. Qi, and Y. Cui, One-Dimensional Helical Transport in Topological Insulator Nanowire Interferometers, Nano Letters 14, 2815-2821 (2014). H. Wang, Z. Lu, D. Kong, J. Sun, T. M. Hymel, and Y. Cui, Electrochemical Tuning of MoS2 Nanoparticles on Three-Dimensional Substrate for Efficient Hydrogen Evolution, ACS Nano 8, 4940-4947(2014). D. Kong, H. Wang, Z. Lu, and Y. Cui, CoSe2 Nanoparticles Grown on Carbon Fiber Paper: An Efficient and Stable Electrocatalyst for Hydrogen Evolution Reaction, J. Am. Chem. Soc. 136, 4897-4900 (2014) DOI: 10.1021/ja501497. J. P. Motter, K. J. Koski, and Y. Cui, General Strategy for Zero-Valent Intercalation into Two-Dimensional Layered Nanomaterials, Chemistry of Materials 26, 2313-2317 (2014). 43 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Two-Dimensional Chalcogenide Nanomaterials Date Submitted: 6/18/2015 FWP#: 100141 16. J. Sun, G. Zheng, H.-W. Lee, N. Liu, H. Wang, H. Yao, W. Yang and Y. Cui, Formation of Stable PhosphorusCarbon Bond for Enhanced Performance in Black Phosphorus Nanoparticle-Graphite Composite Battery Anodes, Nano Letters DOI:10.1021/NL501617j (2014). 17. N. Liu, K. Kim, P.-C. Hsu, A. N. Sokolov, F. L. Yap, H. T. Yuan, Y. W. Xie, H. Yan, Y. Cui, H. Y. Hwang, and Z. N. Bao, Large-Scale Production of Graphene Nanoribbons from Electrospun Polymers. J. Am. Chem. Soc., 136, 17284–17291 (2014). 44 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Joint Center for Energy Storage Research Date Submitted: 6/18/2015 FWP#: 100146 Joint Center for Energy Storage Research (JCESR) Principal Investigator(s): Yi Cui Postdoctoral Scholars and Graduate Students: Weiyang Li, Hongbin Yao Overview The JCESR aims to discover and to study energy storage systems for transportation and grid-scale storage. It integrates a large number of multi-institutional research programs to work together. Yi Cui is one of several PI’s conducting research to support this goal. Progress in FY2015 Lithium polysulfides are intermediate species generated in Li-S battery during cycling. Our previous research (Y. Yang, G. Zheng, Y. Cui, Energy Environ. Sci. 2013, 6, 1552) demonstrated a novel lithium/polysulfide semi-liquid battery system for grid-scale energy storage using lithium polysulfide (Li2S8) and passivated metallic lithium as the catholyte and the anode, respectively. However, practical applications of rechargeable lithium metal-based batteries have been hindered by the formation of dendritic and mossy lithium and associated electrolyte decomposition, resulting in safety concerns and low Coulombic efficiency. Most recently, we demonstrate that lithium dendrite growth can be effectively suppressed via manipulating the chemical reactions of lithium, lithium polysulfide, and lithium nitrate (LiNO3). Both Li2S8 and LiNO3 were used as additives to the ether-based electrolyte, which enables a synergetic effect leading to the formation of a stable and uniform solid electrolyte interphase layer on lithium surface that can greatly minimize the electrolyte decomposition and prevent dendrites from shooting out. By simply manipulating the concentrations of Li2S8 and LiNO3, we show that the formation of lithium dendrites can be prevented at a practical current density of 2 mA cm-2 up to a deposited areal capacity of 6 mAh cm-2. We also demonstrate excellent cyclability: the Coulombic efficiency can be maintained at >99% for over 300 cycles at 2 mA cm-2 with a deposited capacity of 1 mAh cm-2. Even for cyclic deposition of a high areal capacity of 3 mAh cm-2, the average Coulombic efficiency can be as high as 98.5% over 200 cycles (and is higher at ~99.0% between 70 and 200 cycles). In addition, we demonstrate that the precipitation of lithium polysulfide in Li-S battery can be controlled through the electrode design. We propose the tin-doped indium oxide (ITO)-carbon hybrid interface design to understand the spatially controlled deposition of polysulfides on the surface of electrodes and demonstrate its feasibility to improve the performance of Li-S batteries. We show a clear visual evidence that these solid species deposit preferentially onto ITO instead of carbon during electrochemical charge/discharge of soluble polysulfides. To incorporate this concept of spatial control into more practical battery electrodes, we further prepare carbon nanofibers with ITO nanoparticles decorating the surface as hybrid three-dimensional electrodes to maximize the number of deposition sites. With 12.5 µl of 5M Li2S8 as the catholyte and a rate of C/5, we can reach the theoretical limit of Li2S8 capacity ~1470 mAh g-1 (sulfur weight) under the loading of hybrid electrode only at 4.3 mg cm-2). Moreover, we report a novel carbon cluster structure inspired by pomegranate fruits as a framework for sulfur encapsulation for Li-S battery. The resulting sulfur cathode could deliver a high reversible capacity of over 700 mAh/g at an ultrahigh current of 3C (or 10 mA/cm2 equivalent) with a high sulfur mass loading of 2 mg/cm2, corresponding to a volumetric energy density of 1320 Wh/L. The space-efficient packing of the clusters allows for a high tapped density, excellent electrical contact, and the complicated nanoarchitecture effectively inhibits polysulfides dissolution. The enhanced electrochemical behavior shows that this sulfur cathode with pomegranate-like cluster structure represents an effective strategy in improving Li-S battery performance. Finally, instead of using lithium polysulfide and sulfur as cathode materials for Li-S battery, fully lithiated lithium sulfide (Li2S), with its high theoretical specific capacity of 1,166 mAh/g, represents an attractive cathode material because of its compatibility with safer lithium metal-free anodes. Moreover, since Li2S is already in its fully lithiated and fully expanded state, it circumvents the volumetric expansion problem in S cathodes, thus minimizing structural damage at the electrode level. We demonstrate the encapsulation of Li2S with conductive polymers or graphene oxides to improve the conductivity and retard the polysulfides dissolution. Using the Li2S-polypyrrole composites as a cathode 45 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Joint Center for Energy Storage Research Date Submitted: 6/18/2015 FWP#: 100146 material, we demonstrate a high discharge capacity of 785 mAh g-1 of Li2S (~1,126 mAh g-1 of S) with stable cycling over prolonged 400 charge/discharge cycles. Using the Li2S-graphene oxide composites as a cathode material, we demonstrate a high discharge capacity of 782 mAh g-1 of Li2S (~1,122 mAh g-1 of S) with stable cycling performance over 150 charge/discharge cycles. Expected Progress in FY2016 We will continue to develop method to find the perfect encapsulating materials that have high electronic/ionic conductivity to achieve a more complete coating on Li2S to further mitigate against polysulfide dissolution into the electrolyte. We plan to develop additional cost-effective methods to control the depostion sites of lithium polysulfides and systematically investigate the effect of different materials in retarding the polysulfide dissolution. We also plan to develop new methods to lower the activation potential of Li2S and identify any critical size for activation. Expected Progress in FY2017 We plan to pair the stable-cycling Li2S cathodes with lithium metal-free anodes (such as silicon or tin) to achieve a fullcell configuration. Collaborations 1. Prof. Yet-Ming Chiang (MIT). 2. Prof. Qianfan Zhang (Beihang University, China). Publications for FY15 (Oct 1st 2014 to date) Peer-Reviewed Journal Articles 1. Z. W. Seh, H. Wang, P. C. Hsu, Q. Zhang, W. Li, G. Zheng, H. Yao, Y. Cui, “Facile synthesis of Li2Spolypyrrole composite structures for high-performance Li2S cathodes.” Energy Environ. Sci. 2014, 7, 672-676. 2. Z. W. Seh, H. Wang, N. Liu, G. Zheng, W. Li, H. Yao, Y. Cui, “High-capacity Li2S-graphene oxide composite cathodes with stable cycling performance.” Chem. Sci. 2014, 5, 1396-1400. 3. H. Yao, G. Zheng, P. C. Hsu, D. Kong, J. J. Cha, W. Li, Z. W. Seh, M. T. McDowell, K. Yan, Z. Liang, V. K. Narasimhan, Y. Cui, “Improving lithium-sulphur batteries through spatial control of sulphur species deposition on a hybrid electrode surface.” Nat. Commun. 2014, 5: 3943. 4. W. Li, Z. Liang, Z. Lu, H. Yao, Z. W. Seh, K. Yan, G. Zheng, Y. Cui, "A Sulfur Cathode with PomegranateLike Cluster Structure", Adv. Energy Mater. 2015, DOI:10.1002/AENM.201500211. 5. W. Li, H. H. Yao, K. Yan, G. Y. Zheng, Z. Liang, Y.-M. Chiang, and Y. Cui, “The Synergetic Effect of Lithium Polysulfide and Lithium Nitrate to Prevent Lithium Dendrite Growth” Nat. Commun. 2015, In press. 46 Field Work Proposal – SLAC National Accelerator Laboratory Date Submitted: 6/18/2015 SIMES: Nanostructured Design of Sulfur Cathodes for High Energy Lithium-Sulfur Batteries FWP#: 100185 Nanostructured Design of Sulfur Cathodes for High Energy Lithium-Sulfur Batteries Principal Investigator(s): Yi Cui Staff Scientists and Academic Research Associates: Seok Woo Lee Postdoctoral Scholars and Graduate Students: Galvin Cooper, Jang Soo Lee, Sang Han Lee, Dingchang Lin, Frank Luciano, Zhi Wei Seh, Wesley Zheng, Denys Zhuo Visiting Physicists: Xinyong Tao Overview The EERE Vehicle Technology Program has supported research in high-energy lithium-based battery technologies for plug-in-hybrid-electric (PHEV) and electric vehicles (EV), calling for high capacity electrode materials. In this project, we will conduct research on developing sulfur cathodes from the perspective of nanostructured materials design, which will be used to combine with lithium metal anodes to generate high-energy lithium-sulfur batteries. Specifically, we will study the fundamental of lithium-sulfur reaction and design sulfur nanostructures and multifunctional coating to overcome the issues related to volume expansion, polysulfide dissolution and insulating nature of sulfur. We aim to enable high capacity and long cycle life sulfur cathodes Progress in FY2015 In order to improve the performance of sulfur cathode, we develope a 3-D electrode structure to achieve both sulfur physical encapsulation and polysulfides binding simultaneously. The electrode is based on hydrogen reduced TiO2 with an inverse opal structure that is highly conductive and robust toward electrochemical cycling. The openings at the top surface allow sulfur infusion into the inverse opal structure. In addition, chemical tuning of the TiO2 composition through hydrogen reduction was shown to enhance the specific capacity and cyclability of the cathode. With such TiO2 encapsulated sulfur structure, the sulfur cathode could deliver a high specific capacity of 1100 mAh/g in the beginning, with a reversible capacity of 890 mAh/g after 200 cycles of charge/discharge at a C/5 rate. The Coulombic efficiency was also maintained at around 99.5% during cycling. The results showed that inverse opal structure of hydrogen reduced TiO2 represents an effective strategy in improving lithium sulfur batteries performance. We further discover that conductive Magnéli phase Ti4O7 can function as highly effective matrix to bind with sulfur species. Compared with the TiO2-Sulfur composite cathode, the Ti4O7-S cathodes exhibit higher reversible capacity and improved cycling performance. It delivers high specific capacities at various C-rates (1342, 1044, and 623 mAh/g at 0.02, 0.1, and 0.5 C, respectively) and remarkable capacity retention of 99% (100 cycles at 0.1 C). The superior properties of Ti4O7-S are attributed to the strong adsorption of sulfur species on the low-coordinated Ti sites of Ti4O7. Our study demonstrates the importance of surface coordination environment for strongly influencing the S-species binding. These findings can be also applicable to numerous other metal oxide materials. Besides the study of sulfur cathode, fully lithiated lithium sulfide (Li2S) is currently being explored as a promising cathode material for emerging energy storage applications. Like their sulfur counterparts, Li2S cathodes require effective encapsulation to reduce the dissolution of intermediate lithium polysulfide species into the electrolyte. We demonstrate the encapsulation of Li2S cathodes using two-dimensional layered transition metal disulfides that possess a combination of high conductivity and strong binding with lithium sulfide and polysulfide species. In particular, using titanium disulphide as an encapsulation material, we demonstrate a high specific capacity of 503 mAh/g (based on Li2S mass) under high C-rate conditions (4C) as well as high areal capacity of 3.0 mAh/cm2 under high mass-loading conditions (5.3 mg Li2S/cm2). Moreover, we demonstrate the role of the separator in the capacity decay of the lithium-sulfur battery, namely that it can accommodate a large amount of polysulfides inside which then precipitates as a thick layer of inactive S-related species. We develope the use of a thin layer of conductive coating on the separator that can prevent the formation of the inactive 47 Field Work Proposal – SLAC National Accelerator Laboratory Date Submitted: 6/18/2015 SIMES: Nanostructured Design of Sulfur Cathodes for High Energy Lithium-Sulfur Batteries FWP#: 100185 S-related species layer. The large surface area of the conducting coating increased the utilization of the polysulfides accommodated in the separator. We show that the specific capacity and cycling stability of the lithium-sulfur battery are both improved significantly compared to the battery with a pristine separator. Understanding the behavior of soluble intermediate lithium polysulfide species is vitally important for improving the electrochemical performances of lithium-sulfur batteries. We further explore a simple in-operando lithium-sulfur cell design to enable direct visualization of the formation of the soluble polysulfide species and their temporal and spatial distribution over the entire discharge/ charge cycle under an optical microscope. Our results reveal detailed evidence of electrochemical degradation in lithium-sulfur batteries and help us to understand the improvements in electrochemical performances using advanced lithium-sulfur cell designs. As examples, we show that a cathode consisting of hollow sulfur nanoparticles with a conductive polymer coating exhibits significantly reduced dissolution of polysulfides into the electrolyte, and thus superior electrochemical performance could be achieved. Moreover, the trapping of soluble polysulfide species in the cathode side was also confirmed in our designed in-operando lithium-sulfur cell with a Nafion modified separator. Expected Progress in FY2016 Future directions include: 1) increasing the mass and the percentage of sulfur loading in the electrode; 2) tuning different electrolyte additives to improve the Coulombic efficiency and cycling stability; 3) screening a wide range of oxide and sulfide materials for effective polysulfide trapping. Expected Progress in FY2017 We plan to develop approaches to prevent the lithium dendrites growth on lithium metal anodes in lithium-sulfur batteries. We also plan to combine sulfur cathodes with lithiated anodes, such as lithiated silicon, to assemble full batteries to eliminate the safety concern of using lithium metal. Collaborations 1. 2. Prof. Qianfan Zhang (Beihang University, China). Prof. Weihui Zhang (Zhejiang University of Technology, China) Publications for FY15 (Oct 1st 2014 to date) Peer-Reviewed Journal Articles 1. 2. 3. 4. 5. Z. Liang, G. Zheng, W. Li, Z. W. Seh, H. Yao, K. Yan, D. Kong, and Y. Cui, "Sulfur Cathodes with Hydrogen Reduced Titanium Dioxide Inverse Opal Structure", ACS Nano, 2014, 8, 5249-5256. X. Tao, J. Wang, Z. Ying, Q. Cai, G. Zheng, Y. Gan, H. Huang, Y. Xia, C. Lian, W. Zhang and Y. Cui, "Strong Sulfur Binding with Conducting Magneli-Phase TinO2n-1 Nanomaterials for Improving Lithium-Sulphur Batteries", Nano Letters, 2014, 14, 5288-5294. H. Yao, K. Yan, W. Li, G. Zheng, D. Kong, Z. W. Seh, V. K. Narasimhan, Z. Liang, and Y. Cui, "Improved lithium-sulfur batteries with a conductive coating on the separator to prevent the accumulation of inactive Srelated species at the cathode-separator interface", Energy & Environmental Science, 2014, 7, 3381-3390. Z. W. Seh, J. H. Yu, W. Li, P.-C. Hsu, H. Wang, Y. Sun, H. Yao. Q. Zhang, and Y. Cui, "Two-dimensional layered transition metal disulphides for effective encapsulation of high-capacity lithium sulphide cathodes", Nature Communications, 2014, 5: 5017. Y. Sun, Z. W. Seh, W. Li, H. Yao, G. Zheng, and Y. Cui, "In-operando optical imaging of temporal and spatial distribution of polysulfides in lithium-sulfur batteries", Nano Energy, 2015, 11, 579-586 48 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Pre-Lithiation of Silicon Anode for High Energy Li Ion Batteries Date Submitted: 6/18/2015 FWP#: 100186 Pre-Lithiation of Silicon Anode for High Energy Li Ion Batteries Principal Investigator(s): Yi Cui Postdoctoral Scholars and Graduate Students: Yuzhang Li, Zheng Liang, Dingchang Lin, and Jie Zhao Overview Prelithiation of high capacity electrode materials such as Si is an important means to enable those materials in high energy batteries. Here we explore several methods of prelithiation in order to understand their impact on the electrochemical property and cyclability of Si anodes. We aim to identify the best and most practical prelithiation methods. Progress in FY2015 Rapid progress has been made in realizing battery electrode materials with high capacity and long-term cyclability in the past decade. However, the problem of irrerversible capacity loss in the first cycle remains unresolved. Prelithiation is becoming an important strategy to compensate for this lithium loss in lithium-ion batteries, particularly during the formation of solid electrolyte interphase (SEI) from reduced electrolytes in the first charging cycle. We demonstrated that thermal-alloying synthesized LixSi nanoparticles (NPs) can serve as a high-capacity (>2200 mAh/g Si) prelithiation reagent although its chemical stability in the battery processing environment remained to be improved. Therefore, we developed a surface modification method to enhance the stability of LixSi nanoparticles by exploiting the reduction of 1fluorodecane on the LixSi surface to form a continuous and dense coating, through a similar reaction process to SEI formation. The coating, consisting of LiF and Lithium alkyl carbonate with long hydrophobic carbon chains, serves as an effective passivation layer underambient environment. Remarkably, artificial-SEI protected LixSi NPs show a high prelithiation capacity of 2100 mAh/g with negligible capacity decay in dry air after 5 days and maintain a high capacity of 1600 mAh/g in humid air (~10% RH). Silicon, tin and graphite were successfully prelithiated with these NPs to eliminate the irreversible first cycle capacity loss. Thus, incorporation of coated LixSi NPs is a promising approach that may enable the commercial implementation of high-capacity nanostructured materials with large irreversible capacity loss during the first cycle, which is a significant step towards high-energy-density Li-ion batteries. Expected Progress in FY2016 We will continue to develop different kinds of prelithiation reagents. The target is to develop high capacity prelithiation reagents from low cost materials. Ambiant air stability of prelithiation reagents will be enhanced by different coatings. Finally, it should be stable in the ambient air for at least 6 h. We will continue to evaluate these particles blended with Si, Tin and carbon anodes. Expected Progress in FY2017 Different nanostructures will be ultilized to achieve fully lithiated Si with stable cycling performance. This material itself will be used as anode material and paired with high capacity lithium-free cathode materials, such as Sulfur, to realize new generation high-energy density lithium ion battery. Collaborations None. Publications for FY15 (Oct 1st 2014 to date) 49 Field Work Proposal – SLAC National Accelerator Laboratory SIMES: Pre-Lithiation of Silicon Anode for High Energy Li Ion Batteries Date Submitted: 6/18/2015 FWP#: 100186 Peer-Reviewed Journal Articles 1. Zhao, J. et al. Dry-air-stable lithium silicide–lithium oxide core–shell nanoparticles as high-capacity prelithiation reagents. Nat. Commun. 5 (2014). 2. Zhao, J. et al. Artificial Solid Electrolyte Interphase Protected LixSi Nanoparticles: An Efficient and Stable Prelithiation Reagent for Lithium-ion Batteries. Manuscript under review. 50