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Electrical Tuning of Polarizaion-state Using Graphene-Integrated Metasurfaces
Authors:
Nima Dabidian,
Shourya Dutta-Gupta,
Iskandar Kholmanov,
Mikhail Belkin,
Gennady Shvets
Abstract:
Plasmonic metasurfaces have been employed for tuning and controlling light enabling various novel applications. Their appeal is enhanced with the incorporation of an active element with the metasurfaces paving the way for dynamic control. In this letter, we realize a dynamic polarization state generator using graphene-integrated anisotropic metasurface (GIAM), where a linear incidence polarization…
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Plasmonic metasurfaces have been employed for tuning and controlling light enabling various novel applications. Their appeal is enhanced with the incorporation of an active element with the metasurfaces paving the way for dynamic control. In this letter, we realize a dynamic polarization state generator using graphene-integrated anisotropic metasurface (GIAM), where a linear incidence polarization is controllably converted into an elliptical one. The anisotropic metasurface leads to an intrinsic polarization conversion when illuminated with non-orthogonal incident polarization. Additionally, the single-layer graphene allows us to tune the phase and intensity of the reflected light on the application of a gate voltage, enabling dynamic polarization control. The stokes polarization parameters of the reflected light are measured using rotating polarizer method and it is demonstrated that a large change in the ellipticity as well as orientation angle can be induced by this device. We also provide experimental evidence that the titl angle can change independent of the ellipticity going from positive values to nearly zero to negative values while ellipticity is constant.
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Submitted 16 January, 2017;
originally announced January 2017.
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Optical generation and detection of local non-equilibrium phonons in suspended graphene
Authors:
Sean Sullivan,
Ajit Vallabhaneni,
Iskandar Kholmanov,
Xiulin Ruan,
Jayathi Murthy,
Li Shi
Abstract:
The measured frequencies and intensities of different first- and second- order Raman peaks of suspended graphene are used to show that optical phonons and different acoustic phonon polarizations are driven out of local equilibrium inside a sub-micron laser spot. The experimental results are correlated with a first principles-based multiple temperature model to suggest a considerably lower equivale…
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The measured frequencies and intensities of different first- and second- order Raman peaks of suspended graphene are used to show that optical phonons and different acoustic phonon polarizations are driven out of local equilibrium inside a sub-micron laser spot. The experimental results are correlated with a first principles-based multiple temperature model to suggest a considerably lower equivalent local temperature of the flexural phonons than those of other phonon polarizations. The finding reveals weak coupling between the flexural modes with hot electrons and optical phonons. Since the ultrahigh intrinsic thermal conductivity of graphene has been largely attributed to contributions from the flexural phonons, the observed local non-equilibrium phenomena have important implications for understanding energy dissipation processes in graphene-based electronic and optoelectronic devices, as well as in Raman measurements of thermal transport in graphene and other two-dimensional materials.
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Submitted 11 January, 2017;
originally announced January 2017.
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Experimental Demonstration of Phase Modulation and Motion Sensing Using Graphene-Integrated Metasurfaces
Authors:
Nima Dabidian,
Shourya Dutta-Gupta,
Iskandar Kholmanov,
Feng Lu,
Jongwon Lee,
Kueifu Lai,
Mingzhou Jin,
Babak Fallahazad,
Emanuel Tutuc,
Mikhail A. Belkin,
Gennady Shvets
Abstract:
Plasmonic metasurfaces are able to modify the wavefront by altering the light intensity, phase and polarization state. Active plasmonic metasurfaces would allow dynamic modulation of the wavefront which give rise to interesting application such as beam-steering, holograms and tunable waveplates. Graphene is an interesting material with dynamic property which can be controlled by electrical gating…
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Plasmonic metasurfaces are able to modify the wavefront by altering the light intensity, phase and polarization state. Active plasmonic metasurfaces would allow dynamic modulation of the wavefront which give rise to interesting application such as beam-steering, holograms and tunable waveplates. Graphene is an interesting material with dynamic property which can be controlled by electrical gating at an ultra-fast speed. We use a graphene-integrated metasurface to induce a tunable phase change to the wavefront. The metasurface supports a Fano resonance which produces high-quality resonances around 7.7 microns. The phase change is measured using a Michleson interferometry setup. It is shown that the reflection phase can change up to 55 degrees. In particular the phase can change by 28 degrees while the amplitude is nearly constant. The anisotropic optical response of the metasurface is used to modulate the ellipticity of the reflected wave in response to an incident field at 45 degree. We show a proof of concept application of our system in potentially ultra-fast laser interferometry with sub-micron accuracy.
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Submitted 22 October, 2015; v1 submitted 14 October, 2015;
originally announced October 2015.
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Strong Modulation of Infrared Light using Graphene Integration with Plasmonic Fano-Resonant Metasurfaces
Authors:
Nima Dabidian,
Iskandar Kholmanov,
Alexander B. Khanikaev,
Kaya Tatar,
Simeon Trendafilov,
S. Hossein Mousavi,
Carl Magnuson,
Rodney S. Ruoff,
Gennady Shvets
Abstract:
Plasmonic metasurfaces represent a promising platform for enhancing light-matter interaction. Active control of the optical response of metasurfaces is desirable for applications such as beam-steering, modulators and switches, biochemical sensors, and compact optoelectronic devices. Here we use a plasmonic metasurface with two Fano resonances to enhance the interaction of infrared light with elect…
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Plasmonic metasurfaces represent a promising platform for enhancing light-matter interaction. Active control of the optical response of metasurfaces is desirable for applications such as beam-steering, modulators and switches, biochemical sensors, and compact optoelectronic devices. Here we use a plasmonic metasurface with two Fano resonances to enhance the interaction of infrared light with electrically controllable single layer graphene. It is experimentally shown that the narrow spectral width of these resonances, combined with strong light/graphene coupling, enables reflectivity modulation by nearly an order of magnitude leading to a modulation depth as large as 90%. . Numerical simulations demonstrate the possibility of strong active modulation of the phase of the reflected light while keeping the reflectivity nearly constant, thereby paving the way to tunable infrared lensing and beam steering
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Submitted 5 May, 2014;
originally announced May 2014.