A Dual-Band Guided-Laser Absorber Based on Silicon-Nickel Metasurface

Abstract

Metasurface absorbers are already used in many laser applications. To achieve laser stealth, a dual-band guided-laser absorber is presented in this paper. The absorber is composed of periodic silicon squares on a silicon film and a nickel layer. Under normal incidence, the absorber has two absorption peaks at wavelengths of 1.55 μm and 1.064 μm, with absorption rates higher than 94.4%. For wavelength-tunable 1.55 μm lasers with a large wavelength tuning range of ±50 nm, the absorption rate is still as high as 90%. Plasmonic resonance theory, as well as FDTD simulations, are used to design and study the absorber. It is found that the absorber is independent of the incident polarization and tolerant to the incident angle. The design method is flexible, and the absorber is easy to manufacture.