Reproducibility of High-Performance Quantum Dot Single-Photon Sources

Single-photon sources based on semiconductor quantum dots have emerged as an excellent platform for high efficiency quantum light generation. However, scalability remains a challenge since quantum dots generally present inhomogeneous characteristics. Here we benchmark the performance of 15 deterministically fabricated single-photon sources. They display an average single-photon purity of 95.4% ± 1.5% with an average mean wavepacket overlap of 88.0% ± 3.1% corresponding to a single-photon indistinguishability of 92.2% ± 2.6% and high homogeneity in operation wavelength and temporal profile. Each source also has state-of-the-art brightness with an average first lens brightness value of 13.6% ± 4.4%. While the highest brightness is obtained with charged quantum dots, the highest quantum purity is obtained with neutral ones. We also introduce various techniques to identify the nature of the emitting state. Our study sets the groundwork for large-scale fabrication of identical sources.