Quantum clock synchronization over 20-km multiple segmented fibers with frequency-correlated photon pairs and HOM interference
Quantum clock synchronization over 20-km multiple segmented fibers with frequency-correlated photon pairs and HOM interference
复制标题
具有频率相关光子对和 HOM 干扰的 20 公里多分段光纤上的量子时钟同步
DOI：
10.1063/5.0061478
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发表时间：
2021
影响因子：
4
通讯作者：
Shougang Zhang
中科院分区：
文献类型：
--
作者：
Yuting Liu;Runai Quan;Xiao Xiang;Huibo Hong;Mingtao Cao;Tao Liu;Ruifang Dong;Shougang Zhang
基于频率相关光子对和HOM干涉的量子同步凭借高精度的时频信号，已经展现出飞秒级的精度和在众多领域的巨大应用前景。由于长距离光纤传输后难以获得稳定的HOM干涉条纹，这种量子同步在长距离现场应用中受到了阻碍。利用分段光纤代替单根长光纤，在不采用辅助相位稳定方法的情况下，成功实现了实验室开发的宽带频率相关光子对在20公里长光纤传输后的双光子干涉的稳定观测。参考该干涉条纹，成功实现了两个光纤臂的平衡，并具有 20 fs 的长期稳定性。由此证明了 20 公里光纤链路上基于 HOM 干扰的同步，并且在 48,000 秒时达到了 74 fs 的最低稳定性。这一结果不仅为长距离量子通信系统稳定光纤双光子干涉仪提供了一种简单的方法，而且在将基于量子干涉的同步方案扩展到长距离现场应用方面迈出了一大步。
The quantum synchronization based on frequency-correlated photon pairs and HOM interference has shown femtosecond-level precision and great application prospect in numerous fields depending on high-precision timefrequency signals. Due to the difficulty of achieving stable HOM interference fringe after long-distance fiber transmission, this quantum synchronization is hampered from long-haul field application. Utilizing segmented fibers instead of a single long-length fiber, we successfully achieved the stable observation of the two-photon interference of the lab-developed broadband frequency-correlated photon pairs after 20 km-long fiber transmission, without employing auxiliary phase stabilization method. Referenced to this interference fringe, the balance of the two fiber arms is successfully achieved with a long-term stability of 20 fs. The HOM-interference-based synchronization over a 20-km fiber link is thus demonstrated and a minimum stability of 74 fs has been reached at 48,000 s. This result not only provides a simple way to stabilize the fiber-optic two-photon interferometer for long-distance quantum communication systems, but also makes a great stride forward in extending the quantum-interference-based synchronization scheme to the long-haul field applications.