A silicon carbide room-temperature single-photon source

Abstract

Over the past few years, single-photon generation has been realized in numerous systems: single molecules¹, quantum dots^2,3,4, diamond colour centres⁵ and others⁶. The generation and detection of single photons play a central role in the experimental foundation of quantum mechanics⁷ and measurement theory⁸. An efficient and high-quality single-photon source is needed to implement quantum key distribution, quantum repeaters and photonic quantum information processing⁹. Here we report the identification and formation of ultrabright, room-temperature, photostable single-photon sources in a device-friendly material, silicon carbide (SiC). The source is composed of an intrinsic defect, known as the carbon antisite–vacancy pair, created by carefully optimized electron irradiation and annealing of ultrapure SiC. An extreme brightness (2×10⁶ counts s⁻¹) resulting from polarization rules and a high quantum efficiency is obtained in the bulk without resorting to the use of a cavity or plasmonic structure. This may benefit future integrated quantum photonic devices⁹.