Multilayer graphene-based radiation modulator for adaptive infrared camouflage with thermal management

Abstract

Graphene film is a promising thermal camouflage and thermal management material because of its thin, light, flexible structural characteristics and controllable broad-spectrum electromagnetic radiation modulation properties. In this study, a thermal radiation modulator (TRM) based on multilayer graphene (MLG) was studied by simulation and an equivalent transmission line model. The physical mechanism underlying the spectral characteristics and the sensitivity of infrared (IR) radiation modulation to the number of graphene layers is revealed. Furthermore, to solve the problem of thermal instability in the MLG-based TRM, a design scheme integrating a TRM and a meta-absorber is proposed. By electrical control of the MLG, the improved modulator can achieve dynamic emissivity modulation in the wavelength ranges of 3–5 µm and 8–14 µm for adaptive thermal camouflage while maintaining a high emissivity at 5–8 µm for radiative cooling. The compatibility of tunable IR emission and radiative heat dissipation enables graphene to be used for thermal camouflage in complex environments and at high temperatures. The results not only promote the exploration of advanced thermal camouflage materials or devices but also provide inspiration for the application of graphene in thermal management, thermophotovoltaics, IR displays and communications.