A polarization-insensitive and dynamic-tunable perfect absorber for a compatible infrared-visible multi-band stealth

Abstract

With the rapid development of infrared detection technology, infrared stealth technology has evolved to focus not only on low infrared emissivity but also on achieving target stealth from multiple perspectives, including tunable optical performance, effective thermal management, and multispectral compatible stealth. This study developed a multilayer thin-film structure (ZnS/Ge/Ge₂Sb₂Te₅ (GST)/Ag) that can simultaneously achieve both visible camouflage and infrared stealth, with an operating wavelength band spanning the entire visible region and the infrared detection window. A wide range of color shifts is achieved in the visible band, and a green-yellow-orange-violet-blue-green color cycle is obtained. The structure can achieve dynamic switching between stealth and non-stealth modes by adjusting the phase state of the functional layer GST. The average emissivity of the structure in the whole infrared band in the stealthy state is only 2.1 %. A perfect absorption rate of 99.4 % can be achieved in the non-stealthy state, realizing the heat dissipation of the structure. In addition, since the structure has a high degree of symmetry, it is insensitive to polarization and can maintain stable stealth switching at large incidence angles up to 60°. The top layer structure and multiple adapted substrates can also be changed according to the application's needs. This work has great potential in multi-band compatible switching to advanced adaptive cloaking technology, with promising applications in advanced military camouflage, infrared optics, and intelligent thermal management systems.