Improved Evaluation of BBR and Collisional Frequency Shifts of NIM-Sr2 with 7.2×10^(-18)Total Uncertainty  

作　　者：Bing-Kun Lu Zhen Sun Tao Yang Yi-Ge Lin Qiang Wang Ye Li Fei Meng Bai-Ke Lin Tian-Chu Li Zhan-Jun Fang 卢炳坤;孙震;杨涛;林弋戈;王强;李烨;孟飞;林百科;李天初;方占军(Division of Time and Frequency Metrology,National Institute of Metrology,Beijing 100029,China;Department of Precision Instrument,Tsinghua University,Beijing 100084,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

出　　处：《Chinese Physics Letters》2022年第8期22-27,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 Nos.2021YFF0603802 and 2016YFF0200201)。

摘　　要：NIM-Sr2 optical lattice clock has been developed on the Changping campus of National Institute of Metrology(NIM).Considering the limitations in NIM-Sr1,several improved parts have been designed including a differential pumping stage in the vacuum system,a permanent magnet Zeeman slower,water-cooled anti-Helmholtz coils,an extended viewport for Zeeman slower,etc.A clock laser with a short-time stability better than 3×10^(-16)is realized based on a self-designed 30-cm-long ultra-low expansion cavity.The systematic frequency shift has been evaluated to an uncertainty of 7.2×10^(-18),with the uncertainty of BBR shift and the collisional frequency shift being an order of magnitude lower than the last evaluation of NIM-Sr1.

关 键 词：PUMPING SLOWER SHIFT 

分 类 号：TH714[机械工程—测试计量技术及仪器]