文摘
Sources of single photons are of central importance for the realization of several quantum information technologies including teleportation, cryptography, true random number generation, metrology, and some varieties of quantum computing. In principle the generation of single photons can be achieved via an optical transition in a quantum two-level system sufficiently separated from its environment. Solid-state semiconductor quantum dots are convenient structures that can provide such two-level systems, with engineered and tunable transition energies, but cryogenic temperatures are required in the vast majority of experiments in order to facilitate both carrier confinement and spectral isolation. The large-scale on-chip integration of such devices, however, due to inherent system heating, will require individual elements that can operate at temperatures in excess of room temperature. Here we report single-photon emission from an isolated state in a position-controlled GaN nanowire quantum dot at an unprecedented ambient temperature of 350 K (170 °F, 77 °C).