Thermally switchable polarization manipulation and diodelike transmission in scalable, resonator-free, mid-infrared metasurfaces with vanadium-dioxide grids

Abstract

We conceptualized three-array scalable metasurfaces comprising only three thin strip grids and numerically demonstrated their characteristics in the mid-infrared spectral regime for switchable polarization manipulation and related asymmetric diodelike transmission (AT). A few or all of the grids were taken to be made of VO2, a phase-change material. For each proposed metasurface, two effective structures and, therefore, two different functionalities exist, corresponding to the metallic and insulating phases of VO2. The achieved scenarios of functionality switching that depend on the VO2 phase are shown to significantly depend in the way in which VO2 is incorporated to the metasurface. Switchable bands of polarization manipulation are up to 40 THz wide. The AT band can be modulated when Fabry-Perot (anti-)resonances come into play.