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Scientia Sinica Informationis

非平衡光纤干涉仪的相位稳定方法研究

Chuanrong Yang, Chenzhi Yuan, Yunru Fan, Ruiming Zhang, Jiarui Li, Guangwei Deng, Haizhi Song, You Wang, Lixing You, Qiang Zhou

Published Feb 1, 2022• 0 citations

Abstract

By using photons to carry quantum information, optical quantum information technology plays an essential role in quantum communication, quantum metrology, and linear optical quantum computing. In recent years, the unbalanced fiber interferometer has been widely applied in preparing, manipulating, and measuring photon qubits. However, the unbalanced fiber interferometer based on fiber devices is sensitive to the environment's thermal, mechanical, and acoustic noise. Thus, phase stabilization based on feedback control is essential in utilizing an unbalanced fiber interferometer. The existing phase stabilization methods typically employ a reference laser combined with optoelectronic detection, thus introducing additional noise to photon qubits. In this paper, we propose and demonstrate a feedback control method to stabilize a phase in an unbalanced fiber interferometer by combining weak coherent reference light and single photon counting. Using theoretical analysis, we realized the phase stabilization of an unbalanced fiber Michelson interferometer with an arm-length difference of about 1 m. The results showed that the jitter of the stabilized phase is less than 0.042 rad, while the visibility of single-photon interference fringes is higher than 99%.

DOI: 10.1360/ssi-2021-0410

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