English

Implementation of field two-way quantum synchronization of distant clocks across a 7 km deployed fiber link

Quantum Physics 2022-04-06 v2

Abstract

The two-way quantum clock synchronization has been shown not only providing femtosecond-level synchronization capability but also security against symmetric delay attacks, thus becoming a prospective method to compare and synchronize distant clocks with both enhanced precision and security. In this letter, a field test of two-way quantum synchronization between a H-maser and a Rb clock linked by a 7 km-long deployed fiber was implemented. Limited by the frequency stability of the Rb clock, the achieved time stability at 30 s was measured as 32 ps. By applying a fiber-optic microwave frequency transfer technology, the stability was improved by more than one-magnitude to 1.9 ps, even though the number of acquired photon pairs was only 1440 in 30 s due to the low sampling rate of the utilized coincidence measurement system. Such implementation demonstrates the high practicability of two-way quantum clock synchronization method for promoting the field applications.

Keywords

Cite

@article{arxiv.2109.00784,
  title  = {Implementation of field two-way quantum synchronization of distant clocks across a 7 km deployed fiber link},
  author = {Runai Quan and Huibo Hong and Wenxiang Xue and Honglei Quan and Wenyu Zhao and Xiao Xiang and Yuting Liu and Mingtao Cao and Tao Liu and Shougang Zhang and Ruifang Dong},
  journal= {arXiv preprint arXiv:2109.00784},
  year   = {2022}
}