A bioinspired switchable selective infrared solar absorber by tunable optical coupling

Abstract

Harvesting energy from sunlight is an essential component of thermal load in an outdoor environment. Controlling the solar heating effects is therefore important. Inspired by the tunable coupling of the pigment cells and iridocytes in squid skin, we simulated a design for the tunable coupling of a grating and hyperbolic material. This composite metamaterial possessed thermoregulatory properties. The tiny mechanical action (∼250 nm) can tune the solar absorptive quality from 0.9 to 0.03 while keeping the radiative quality small. Our findings could have applications in dynamic and simply controlled thermoregulatory systems for outdoor structures and other technologies that regulate solar infrared absorption.