Deterministic and Robust Generation of Single Photons On a Chip with 99.5% Indistinguishability Using Rapid Adiabatic Passage

We demonstrate deterministic and robust generation of pulsed resonance fluorescence single photons from a single InGaAs quantum dot using the method of rapid adiabatic passage. Comparative study is performed with transform-limited, negatively chirped and positively chi rped pulses, identifying the last one to be the most robust against fluctuation of driving strength. The generated sing le photons are background free, have a vanishing twophoton emission probability of 0.3% and a raw (corrected) two-photon Hong-Ou-Mandel interference visibility of 97.9% (99.5%), reaching a precision that places single photons at the threshold for fault-tolerant surface-code quantum computing. The single-photon source can be readily scaled up to multi-photon entanglement and used for quantum metrology, boson sampling and linear optical quantum computing.