Frontiers of Physics

Single-photon source with sub-MHz linewidth for cesium-based quantum information processing

Hai Dan He, Pengfei Yang, Pengfei Zhang, Gang Li, Tiancai Zhang

Published Jul 12, 2023• 7 citations

Abstract

A single-photon source with narrow bandwidth, high purity, and large brightness can efficiently interact with material qubits strongly coupled to an optical microcavity for quantum information processing. Here, we experimentally demonstrate a degenerate doubly resonant single-photon source at 852 nm by the cavity-enhanced spontaneous parametric down-conversion process with a 100% duty cycle of generation. The single photon source possesses both high purity with a second-order correlation g (2) (0) = 0.021 and narrow linewidth with Δνsp = (800 ± 13) kHz. The single-photon source is compatible with the cesium atom D2 line and can be used for cesium-based quantum information processing.

DOI: 10.1007/s11467-023-1317-z

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