An outstanding goal in quantum optics and scalable photonic quantum technology is to develop a source that each time emits one and only one entangled photon pair with simultaneously high entanglement fidelity, extraction efficiency, and photon indistinguishability. By coherent two-photon excitation of a single InGaAs quantum dot coupled to a circular Bragg grating bullseye cavity with broadband high Purcell factor up to 11.3, we generate entangled photon pairs with a state fidelity of 0.90(1), pair generation rate of 0.59(1), pair extraction efficiency of 0.62(6), and photon indistinguishability of 0.90(1) simultaneously. Our work will open up many applications in high-efficiency multi-photon experiments and solid-state quantum repeaters.
@article{arxiv.1903.06071,
title = {On-demand semiconductor source of entangled photons which simultaneously has high fidelity, efficiency, and indistinguishability},
author = {Hui Wang and Hai Hu and T. -H. Chung and Jian Qin and Xiaoxia Yang and J. -P. Li and R. -Z. Liu and H. -S. Zhong and Y. -M. He and Xing Ding and Y. -H. Deng and C. Schneider and Qing Dai and Y. -H. Huo and Sven Höfling and Chao-Yang Lu and Jian-Wei Pan},
journal= {arXiv preprint arXiv:1903.06071},
year = {2019}
}