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Download Research Opportunities at LCLS - Stanford Synchrotron Radiation
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Research Opportunities at LCLS September 2011 Joachim Stöhr Five Revolutions in “light” • 1879 - Invention of the light bulb • 1895 - Discovery of X-Rays • 1960 - Invention of the LASER • 1970 - Synchrotron radiation x-rays - SSRL • 2009 - The first x-ray laser - LCLS The speed of things – the smaller the fast manifestation of the physical concept of “inertia” = resistance to motion, action, or change macro molecules molecular groups atoms “electrons” & “spins” Laser flash The new science paradigm: Static “structure” plus dynamic “function” Present technological speeds Future technological speeds X-ray Lasers Important areas of LCLS research Because of their size, atoms and “bonds” can change fast but how do systems evolve? key areas of interest: equilibrium (phase diagrams of complex materials…) close to equilibrium (operation or function of a system…) far from equilibrium (transient states like a chemical reaction…) far, far from equilibrium (matter during inertial confinement fusion…) “Equilibrium”: What is the structure of water? Small angle x-ray scattering shows inhomogeneity Disordered soup Ice like clusters Components probably dynamic – form and dissolve - can we take an ultrafast snapshot?? How do we image with LCLS? “Close to equilibrium” – how does a device function: e.g. how does a spin current turn the magnetization ? magnetic switching today in 1 ns how fast can it be done? “bit” in cell 100 nm Computer chip Electronic circuit Memory cell Magnetic structure of “bit” “Far from equilibrium”: How does a chemical reaction proceed? reaction dynamics & intermediates end reaction products What are the key intermediate reactive species? “Far, far from equilibrium”: Warm and hot dense matter The properties of matter in extreme states - which on earth can only be created transiently on ultrafast time scale- Sample “Image before destroy” snapshots femtosecond protein crystallography • Atoms = electronic cores move slow enough so that “image before destruction” becomes possible at LCLS requirements: maximum intensity for signal-to-noise pulse length (~10 fs) shorter than atomic motion (100 fs) LCLS facilities overview Injector electron beam 1km linac 14GeV AMO SXR Undulator hall XPP Near-hall: 3 stations XCS x-ray beam CXI Far-hall: 3 stations MEC 132 meters of FEL undulators Experimental Halls and Operations Schedules Near Experimental Hall AMO SXR XPP X-ray Transport Tunnel 200 m Start of operation AMO Oct-09 SXR May-10 XPP October-10 CXI February-11 XCS Spring-12 MEC Fall-12 < 30Hz 60Hz 60Hz, 120Hz since Jan 2011 XCS CXI MEC Far Experimental Hall Optical laser versus X-ray free electron laser Optical laser X-ray laser • electrons in discrete energy states • a bunch (~109) of free electrons • stimulated emission amplified through mirrors • stimulated emission amplified through electron ordering • fixed photon energy • tunable photon energy • low energy, long wavelength photons • high energy, short wavelength photons • compact • large The end
