Nanowire Quantum Dot Surface Engineering for High Temperature Single Photon Emission.

Generating single photons at high temperature remains a major challenge, particularly for group III-As and III-P materials widely used in optical communication. Here, we report a high temperature single photon emitter based on a "surface-free" GaAs quantum dot (QD) in a GaAsP nanowire. By using self-catalyzed vapor-liquid-solid growth and simple surface engineering, we can significantly enhance the optical signal from the QDs with a highly polarized photoluminescence at 750 nm. The "surface-free" nanowire quantum dots show photon antibunching up to 160 K and well resolved exciton lines as high as 220 K.