A triple-mode mid-infrared modulator for all-surface radiative thermal management

TL;DR

This paper introduces a triple-mode mid-infrared modulator capable of switching between emission, reflection, and transmission modes, enabling adaptive radiative thermal management for various surface emissivities in a sustainable and versatile manner.

Contribution

The authors develop a novel elastomer-based device that can dynamically switch infrared modes, offering a new approach for surface-based radiative heat control across different materials.

Findings

Achieved emittance contrast of 0.58

Achieved transmittance contrast of 0.49

Achieved reflectance contrast of 0.39

Abstract

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 surface emissivities require different tuning strategies. Here, we demonstrate a triple-mode mid-infrared modulator that can switch between passive heating and cooling suitable for all types of object surface emissivities. The device is composed of a surface-textured infrared-semi-transparent 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 of emittance contrast = 0.58, transmittance contrast = 0.49, and reflectance contrast = 0.39. The device can provide a new design paradigm of radiation heat regulation to develop the next generation wearable devices, robotics, and camouflage technology.