Remote Comparison of Two Sr Optical Lattice Clocks through a 58 km Fiber Link  

作　　者：Tang-Yin Liao Hao Liu Fei Meng Qiang Wang Tao Yang Hao-Chen Tian Bing-Kun Lu Lin Zhu Ye Li Bai-Ke Lin Zhan-Jun Fang Yi-Ge Lin 廖堂银;刘豪;孟飞;王强;杨涛;田昊晨;卢炳坤;朱琳;李烨;林百科;方占军;林弋戈(Division of Time and Frequency Metrology,National Institute of Metrology,Beijing 100029,China;Department of Precision Instrument,Tsinghua University,Beijing 100084,China;Key Laboratory of Time Frequency and Gravity Primary Standard,State Administration for Market Regulation,Beijing 100029,China;Institute of Precision Optical Engineering,School of Physics Science and Engineering,Tongji University,Shanghai 200092,China;Hefei National Laboratory,Hefei 230088,China)

机构地区：[1]Division of Time and Frequency Metrology,National Institute of Metrology,Beijing 100029,China [2]Department of Precision Instrument,Tsinghua University,Beijing 100084,China [3]Key Laboratory of Time Frequency and Gravity Primary Standard,State Administration for Market Regulation,Beijing 100029,China [4]Institute of Precision Optical Engineering,School of Physics Science and Engineering,Tongji University,Shanghai 200092,China [5]Hefei National Laboratory,Hefei 230088,China

出　　处：《Chinese Physics Letters》2025年第3期63-68,共6页中国物理快报(英文版)

基　　金：supported by the National Key R&D Program of China(Grant No.2021YFF0603802);the National Natural Science Foundation of China(Grant No.61905231);the State Administration for Market Regulation(Grant No.CXTD202301);the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0300902)。

摘　　要：Two^(87)Sr optical lattice clocks(OLCs)are being developed and operated at the National Institute of Metrology(NIM),located on different campuses that are 40km apart.In order to compare the optical frequencies of these two Sr OLCs,a 58-km noise canceled fiber link is built to transfer both a 1542-nm transfer laser and a microwave reference from Changping campus to Hepingli campus.Two commercial optical frequency combs(OFCs)with adapted single-branch 698/1542nm outputs coherently unite the two 698-nm clock lasers and the 1542-nm transfer laser.The fractional instability of the comparison yields 3.1×10^(−17)at 10000 s averaging time.The measured fractional frequency difference between these two Sr OLCs was evaluated to be 1.9(3.2)×10^(−17),which is within their claimed uncertainties.This result demonstrates the consistency of their frequencies when they serve as optical frequency standards.Our remote comparison demonstrates the feasibility of optical clock comparison through a long-distance fiber link and contributes to the progress of redefinition of the SI second.

关 键 词：FIBER FRACTIONAL LATTICE 

分 类 号：TN2[电子电信—物理电子学]