A Triple-Mode Midinfrared Modulator for Radiative Heat Management of Objects with Various Emissivity

Thermal management is ubiquitous in the modern world and indispensable for a sustainable future. Radiative heat management provides unique advantages because the heat transfer can be controlled by the surface. However, different object emissivities require different tuning strategies, which poses challenges to develop dynamic and universal radiative heat management devices. Here, we demonstrate a triple-mode midinfrared modulator that can switch between passive heating and cooling suitable for all types of object surface emissivities. The device comprises a surface-textured infrared-semiabsorbing elastomer coated with a metallic back reflector, which is biaxially strained to sequentially achieve three fundamental modes: emission, reflection, and transmission. By analyzing and optimizing the coupling between optical and mechanical properties, we achieve a performance as follows: emittance contrast Delta epsilon = 0.58, transmittance contrast Delta tau = 0.49, and reflectance contrast Delta rho = 0.39. The device can provide a new design paradigm of radiation heat regulation for wearable, robotics, and camouflage technologies.

Automated summary

Thermal management is crucial for sustainable development, and radiative heat management can control heat transfer by the surface. Developing dynamic and universal radiative heat management devices is challenging due to the different tuning strategies required for various object emissivities. By utilizing a surface-textured infrared-semiabsorbing elastomer with a metallic back reflector, an innovative triple-mode midinfrared modulator has been demonstrated, providing high performance and a new design paradigm for radiation heat regulation in wearable, robotics, and camouflage technologies.