Download Deliverable 9: Blueprints of ICT relevant demonstrators As pointed

Deliverable 9: Blueprints of ICT relevant demonstrators
As pointed out in the original PHOME proposal, using chiral metamaterials can be used
as thin-film optical isolators. In addition, we have proposed to use photonic
metamaterials that can be used as tunable switches at THz frequencies, and finally we
have proposed to use photonic metamaterials for electro-optic modulation.
Chirality only exists in truly three-dimensional structures, i.e., it does not occur in planar
metamaterials. Furthermore, chirality enables devices that are immediately relevant for
ICT-related applications such as, e.g., “poor man’s optical isolators” or circular
polarization filters. Combined with non-reciprocal constituent materials, chirality would
also enable true optical isolators based on the Faraday effect in the future. In Fig. 9 we
present the designs and the fabricated samples for GHz and THz frequencies [D9:1, D9:2,
D9:3, D9:4, D9:5, D9:6]. Notice that
Figure 9.1: Comparison of different chiral metamaterials, which were fabricated and
experimentally characterized at GHz and THz frequencies.
the rotation angle per wavelength is around 800o for GHz frequencies, around 400o for 3
microns and around 60o for 1.5 microns. The rotation angle is given with zero ellipticity,
i.e. it means that the linear polarized wave rotates and remains linear polarized. These
new designs, which have been fabricated and measured experimentally, can be used as
thin-film optical isolators.
The second ICT demonstrator is the gold-helix metamaterial that was fabricated [D9:7]
with direct laser writing (DLW) and it was filled with gold using an electroplating
approach. This work can be viewed as a possible first “real-world” application of the farreaching concepts of electromagnetic metamaterials.
Figure D9.2: 3D gold-helix metamaterial serving as
compact, broadband circular polarizer [D9:7].
The
realized
gold-helix
metamaterial can serve as a
compact broadband (more than one
octave
bandwidth)
circular
polarizer
that
might
find
applications
in
infrared
spectroscopy of fingerprints of
chiral molecules. Importantly, a
linear polarizer and a subsequent
quarter-wave plate cannot simply
obtain
broadband
circular
polarization of light. The realized
structures [D9: 7] can be viewed as
the circular analogue of the good
old wire-grid polarizer that is
widely applied for obtaining linear
polarization of light.
The third ICT demonstrator is the dynamic response of metamaterials at the THz regime.
In particular we have made designs, fabricated the samples and characterize them by THz
time-domain spectroscopy. We demonstrate experimentally [D9:8] blueshift tunability
and a broadband phase modulation. This happens when the metamaterial is dynamically
photoexcited, using synchronized femtosecond near-infrared laser pulses. The possibility
of phase modulation under photoexcitation, opens the way of realization of broadband
(250 GHz) phase plate devices in the THz range. In addition, we have designed and
fabricated [D9:9] a new metamaterial device that gives a dual-band switch, which has a
lot of potential applications in switchable devices.
Fig. D9.3: Schematic view of our design for
broadband blue-shift tunable metamaterial.
Fig. D9.4: Optical microscopy image of the
fabricated metamaterial device.
Fig. D9.5: Simulation results of transmission with
different conductivity levels of photoactive silicon.
Fig. D9.6: Experimentally measured transmission for
different levels of energy flux of pump beam.
References D9
[D9: 1] E. Plum, J. Dong, J. Zhou, V. A. Fedotov, Th. Koschny, C. M. Soukoulis, and N. I.
Zheludev, “Metamaterial with Negative Index due to Chirality,” Phys. Rev. B. 79, 035407 (2009);
(Selected for a Viewpoint in Physics 2, 3 (2009)).
[D9:2] J. Zhou, J. Dong, B. Wang, Th. Koschny, M. Kafesaki and C. M. Soukoulis, “Negative
refractive index due to chirality,” Phys. Rev. B. 79, 121104(R) (2009).
[D9:3] M. Decker, M. Ruther, C.E. Kriegler, J. Zhou, C.M. Soukoulis, S. Linden, and M.
Wegener, “Strong optical activity from twisted-cross photonic metamaterials,” Optics. Letters 34,
2501(2009).
[D9:4] Z. Li, R. Zhao, Th. Koschny, M. Kafesaki, E. Colak, H. Caglayan, E. Ozbay and C. M.
Soukoulis, “Chiral metamaterials with negative refractive index based on Four-U-SRRs
resonators,” Appl. Phys. Lett. (submitted).
[D9:5] M. Decker R. Zhao, C.M. Soukoulis, S. Linden, and M. Wegener, “Twisted split-ringresonator photonic metamaterial with huge optical activity,” Opt. Lett. 35, 1593 (2010).
[D9:6] R. Zhao, Th. Koschny and C. M. Soukoulis, “Conjugated-bi-layer swastika-shaped chiral
metamaterial with huge optical activity and negative refractive index,” unpublished.
[D9:7] J.K. Gansel, M. Thiel, M.S. Rill, M. Decker, K. Bade, V. Saile, G. von Freymann, S.
Linden, and M. Wegener, Gold helix photonic metamaterial as broadband circular polarizer,
Science 325, 1513 (2009).
[D9:8] J. M. Manceau, N.-H. Shen, M. Kafesaki, C. M. Soukoulis, and S. Tzortzakis, “Dynamic
response of metamaterials in the terahertz regime: Blue shift tunability and broadband phase
modulation,” Appl. Phys. Lett. 96, 021111 (2010).
[D9:9] N.-H. Shen, M. Massaouti, M. Gokkavas, E. Ozbay, J. M. Manceau, S. Tzortzakis, and C.
M. Soukoulis, “Experimental realization of broadband blue-shift swith in THz regime with all
optical implementation,” unpublished.