Near-perfect photon utilization in an air-bridge thermophotovoltaic cell

Nature, Published online: 21 September 2020; doi:10.1038/s41586-020-2717-7

An air gap embedded within the structure of a thermophotovoltaic device acts as a near-perfect reflector of low-energy photons, resulting in their recovery and recycling by the thermal source, enabling excellent power-conversion efficiency.