title: Electrical tuning of the polarization state of light using graphene-integrated anisotropic metasurfaces.
abstract: Plasmonic metasurfaces have been employed for moulding the flow of transmitted and reflected light, thereby enabling numerous applications that benefit from their ultra-thin sub-wavelength format. Their appeal is further enhanced by the incorporation of active electro-optic elements, paving the way for dynamic control of light's properties. In this paper, we realize a dynamic polarization state generator using a graphene-integrated anisotropic metasurface (GIAM) that converts the linear polarization of the incident light into an elliptical one. This is accomplished by using an anisotropic metasurface with two principal polarization axes, one of which possesses a Fano-type resonance. A gate-controlled single-layer graphene integrated with the metasurface was employed as an electro-optic element controlling the phase and intensity of light polarized along the resonant axis of the GIAM. When the incident light is polarized at an angle to the resonant axis of the metasurface, the ellipticity of the reflected light can be dynamically controlled by the application of a gate voltage. Thus accomplished dynamic polarization control is experimentally demonstrated and characterized by measuring the Stokes polarization parameters. Large changes of the ellipticity and the tilt angle of the polarization ellipse are observed. Our measurements show that the tilt angle can be changed from positive values through zero to negative values while keeping the ellipticity constant, potentially paving the way to rapid ellipsometry and other characterization techniques requiring fast polarization shifting.This article is part of the themed issue 'New horizons for nanophotonics'.
authors.affiliation: Department of Physics, and Center for Nano and Molecular Science and Technology, University of Texas at Austin, Austin, TX 78712, USA.|School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Shourya
authors.initials: S
authors.lastname: Dutta-Gupta
authors.affiliation: Department of Physics, and Center for Nano and Molecular Science and Technology, University of Texas at Austin, Austin, TX 78712, USA.
authors.forename: Nima
authors.initials: N
authors.lastname: Dabidian
authors.affiliation: Department of Mechanical Engineering, and Materials Science Program, University of Texas at Austin, Austin, TX 78712, USA.|CNR-INO, Sensor Lab, University of Brescia, via Branze 45, 25123 Brescia, Italy.
authors.forename: Iskandar
authors.initials: I
authors.lastname: Kholmanov
authors.affiliation: Department of Electrical and Computer Engineering, Microelectronics Research Center, University of Texas at Austin, 10100 Burnet Road, Austin, TX 78758, USA.
authors.forename: Mikhail A
authors.initials: MA
authors.lastname: Belkin
authors.affiliation: Department of Physics, and Center for Nano and Molecular Science and Technology, University of Texas at Austin, Austin, TX 78712, USA gs656@cornell.edu.|School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Gennady
authors.initials: G
authors.lastname: Shvets
keywords: active metasurface; graphene; polarization