Thermally switchable, bifunctional, scalable, mid-infrared metasurfaces with VO2 grids capable of versatile polarization manipulation and asymmetric transmission
Date
2022-12-01Source Title
Optical Materials Express
Print ISSN
21593930
Publisher
Optica Publishing Group (formerly OSA)
Volume
12
Issue
12
Pages
4594 - 4605
Language
English
Type
ArticleItem Usage Stats
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Abstract
We conceptualized three-array scalable bifunctional metasurfaces comprising only three thin strip grids and numerically determined their characteristics in the mid-infrared spectral regime for switchable operation scenarios involving polarization manipulation and related diodelike asymmetric transmission (AT) as one of two functionalities. A few or all of the grids were taken to be made of VO2, a bifunctionality-enabling phase-change material; there are no layers and/or meta-atoms comprising simultaneously both metal and VO2. 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 significantly depend on the way in which VO2 is incorporated into 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. Besides, transmission regimes with the cross-polarized component insensitive to VO2 phase change are possible, as well as the ones with all co- and cross-polarized components having the same magnitude for both linear polarizations of the incident wave. © 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.
Keywords
Fabry-Perot interferometersInfrared devices
Phase change materials
Polarization
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