Reconfigurable All Dielectric Metasurfaces based on Optical Phase Change Materials: Design Approaches
Keywords:GSST, metasurface, metalens, PCM, phase change materials, reconfigurable optics
Optical metasurface is a recently emerged paradigm for controlling light propagation, which enables implementation of ultra-compact optical devices with extended functionalities. Nowadays the main challenge in the field is to realize active metasurfaces with high quality, high efficiency, and large tuning range. Here we present a design approach for constructing a twostate reconfigurable metalens made of low-loss optical phasechange material (O-PCM). The metalens design is capable to produce diffraction limited focusing, large change in focal length (from 1.5 mm to 2mm), and decent focusing efficiency of about 20% in both states. The proposed design methodology is generic and can be easily extended towards constructing metasurfaces, which can switch between two or more arbitrary phase maps.
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