Li Rui, Wu Yuelong, Rui Yang, Li Bo, Jiang Yanyi, Ma Longsheng, Wu Haibin
State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, People's Republic of China.
Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China.
Phys Rev Lett. 2020 Feb 14;124(6):063002. doi: 10.1103/PhysRevLett.124.063002.
We report the precision measurement of the absolute frequencies, hyperfine splitting, and 2P fine structure splitting in cold atoms of ^{6}Li. Using the stabilized optical frequency comb and developed heterodyne detection technique, the photon shot-noise limited optical spectroscopy is achieved. The measurement of absolute frequencies of D_{1} lines is reached with an uncertainty of about 1 kHz, which is 1 order of magnitude more accurate than previous measurements. The hyperfine splitting of the D_{1} line and 2P fine structure splitting of ^{6}Li are 26.103 1 (14) and 10 052.780 4 (18) MHz, respectively, in agreement with recent theoretical calculations. Our results could provide a benchmark to test the theory at the higher precision and help to resolve large discrepancies among previous experiments.
我们报告了对(^{6}Li)冷原子中绝对频率、超精细分裂和(2P)精细结构分裂的精确测量。利用稳定的光学频率梳和开发的外差检测技术，实现了光子散粒噪声限制的光学光谱学。(D_1)线绝对频率的测量不确定度约为(1kHz)，比之前的测量精度提高了一个数量级。(^{6}Li)的(D_1)线超精细分裂和(2P)精细结构分裂分别为(26.103 1 (14))和(10 052.780 4 (18) MHz)，与最近的理论计算结果一致。我们的结果可以为在更高精度下检验理论提供基准，并有助于解决先前实验之间的巨大差异。
