Multilayer planar structure for optimized passive thermal homeostasis [Invited]

We optimize planar, passive thermal-regulation devices that use the phase-change properties of VO 2 . We calculate the tunable total emittance, defined as the difference in normalized radiated power in the insulator and metallic states of VO 2 at the phase transition temperature. A single-layer VO 2 /ZnSe/Au device achieves a tunable total emittance of 0.574 in simulation. An optimized multilayer device using the same materials achieves a value of 0.69 in simulation, which outperforms all planar devices found in the literature. We present an analysis showing that an increase in tunable total emittance reduces the temperature fluctuations experienced by the device within a fluctuating environment.