Nonvolatile High-Contrast Whole Long-Wave Infrared Emissivity Switching Based on In<sub>3</sub>SbTe<sub>2</sub>
Weiyi Zha, Yining Zhu, Binze Ma, Jianbo Yu, Pintu Ghosh, Min Qiu, Qiang Li
Abstract
Switchable thermal emission in the long-wave infrared (LWIR, 8–14 μm) range is of great significance in applications like thermal detection, radiative cooling, and infrared camouflage. Existing methods for switchable LWIR emission apply photonic structures incorporating smart materials, which either require a continuous input power or produce limited emissivity contrasts. In this study, two nonvolatile high-contrast switchable emitters over the whole LWIR range have been proposed utilizing the drastic permittivity change of In3SbTe2 (IST) upon crystallization. One switchable emitter exhibits negative differential emissivity (ΔεN,8–14 μm ≈ −0.75, emissivity decreases with temperature) and is experimentally applied to infrared camouflage; the other shows positive differential emissivity (ΔεP,8–14 μm ≈ 0.83, emissivity increases with temperature) and demonstrates its capability in thermal management. The demonstrated characteristics of IST provide a new route for realizing differential emissivity and make the IST-based emitters highly promising for applications such as infrared camouflage and thermal management.