Design of Hybrid Narrow-Band Plasmonic Absorber Based on Chalcogenide Phase Change Material in the Infrared Spectrum

Abstract

Structures absorbing electromagnetic waves in the infrared spectral region are important optical components in key areas such as biosensors, infrared images and thermal emitters, and require special attention from reconfigurable devices. We propose a three-dimensional metal-dielectric plasmonic absorber with a layer of PCM's (Phase Change Materials). The phase shift effects of PCMs are analyzed, and it is possible to obtain a displacement control in the resonant absorption peaks between the amorphous and crystalline states using the Lorentz-Lorenz relation. Aided in this empirical relation, we analyzed the absorption shift in the intermediate phases between them. The geometric parameters of the structure with the pcm material layer in the semi-crystalline state were optimized to present strong absorption for normal incidence. The effects of the oblique incidence for the TM and TE polarization modes were also analyzed. Our results demonstrate that PCMs have great potential for reconfigurable nanophotonic devices.