title: Dynamic Reflection Phase and Polarization Control in Metasurfaces.
abstract: Optical metasurfaces are two-dimensional optical elements composed of dense arrays of subwavelength optical antennas and afford on-demand manipulation of the basic properties of light waves. Following the pioneering works on active metasurfaces capable of modulating wave amplitude, there is now a growing interest to dynamically control other fundamental properties of light. Here, we present metasurfaces that facilitate electrical tuning of the reflection phase and polarization properties. To realize these devices, we leverage the properties of actively controlled plasmonic antennas and fundamental insights provided by coupled mode theory. Indium-tin-oxide is embedded into gap-plasmon resonator-antennas as it offers electrically tunable optical properties. By judiciously controlling the resonant properties of the antennas from under- to overcoupling regimes, we experimentally demonstrate tuning of the reflection phase over 180°. This work opens up new design strategies for active metasurfaces for displacement measurements and tunable waveplates.
authors.affiliation: Geballe Laboratory for Advanced Materials, Stanford University , Stanford, California 94305, United States.
authors.forename: Junghyun
authors.initials: J
authors.lastname: Park
authors.affiliation: Geballe Laboratory for Advanced Materials, Stanford University , Stanford, California 94305, United States.
authors.forename: Ju-Hyung
authors.initials: JH
authors.lastname: Kang
authors.affiliation: Geballe Laboratory for Advanced Materials, Stanford University , Stanford, California 94305, United States.
authors.forename: Soo Jin
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Geballe Laboratory for Advanced Materials, Stanford University , Stanford, California 94305, United States.
authors.forename: Xiaoge
authors.initials: X
authors.lastname: Liu
authors.affiliation: Geballe Laboratory for Advanced Materials, Stanford University , Stanford, California 94305, United States.
authors.forename: Mark L
authors.identifier: 0000-0003-1777-8970
authors.initials: ML
authors.lastname: Brongersma
keywords: Metasurface; electrical gating; phase control; polarization control