Radiative thermal runaway due to negative differential thermal emission across a solid-solid phase transition

Thermal runaway occurs when a rise in system temperature results in heat generation rates exceeding dissipation rates. Here we demonstrate that thermal runaway occurs in thermal radiative systems, given a sufficient level of negative differential thermal emission. By exploiting the insulator-to-metal phase transition of vanadium dioxide, we show that a small increase in heat generation (e.g., 10 nW/mm2) can result in a large change in surface temperature (e.g., ~35 K), as the thermal emitter switches from high emissivity to low emissivity. While thermal runaway is typically associated with catastrophic failure mechanisms, detailed understanding and control of this phenomenon may give rise to new opportunities in infrared sensing, camouflage, and rectification.