Temperature-driven tunability of a vanadium dioxide-based microcavity made of random sequences of layers

Vanadium dioxide-based photonic devices show significant potential for a range of applications, such as smart windows and reconfigurable optical switches. In this study, we introduce a microcavity design featuring a vanadium dioxide layer positioned between two photonic structures composed of a random sequence of 32 alternating layers of silicon dioxide and zirconium dioxide. The temperature-dependent complex refractive index of vanadium dioxide has been thoroughly accounted for. Our findings reveal that even a temperature change of just 1 °C results in subtle variations in the optical response. These small changes can be detected through differential light transmission measurements, which can be performed using relatively simple and low-cost optical setups. Consequently, the proposed microcavity can serve as an effective temperature sensor or a highly sensitive photon detector, where incident photons induce a temperature rise in the material.