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arXiv · 2106.06940

Multi-spectral programmable absorbers

Yun Meng·Dan Li·Chong Zhang·Yang Wang·Robert E. Simpson·Yi Long
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Abstract

We designed and demonstrated a multi-spectral programmable perfect absorber that exploits two different phase-change materials. This programmability is possible by resonantly coupling two phase change materials, a Ge2Sb2Te5 layer to vanadium dioxide nanoparticles (VO2 NPs). The perfect absorption is attributed to the coalescence of gap plasmon modes excited between the NPs and waveguide cavity-like modes excited between the film and the NPs. The absorptance peak (>90%) can be tuned to four different infrared (IR) wavelengths from 1906 to 2960 nm by heating the structure to different temperatures. The perfect absorber is reconfigurable, lithography-free, large-scale, polarization-insensitive omnidirectional. Our strategy opens a new path for programmable infrared photonics.

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Yun Meng, Dan Li, Chong Zhang, Yang Wang, Robert E. Simpson, Yi Long. 2021-06-13. Multi-spectral programmable absorbers. https://arxiv.org/abs/2106.06940

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