Experimental Determination of the Landé g-Factors for 5s2 1S and 5s5p 3P States of the 87Sr Atom**Supported by the National Natural Science Foundation of China under Grant Nos 61127901, 11404025 and 91536106, the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No XDB21030700, the Key Research Project of Frontier Science of Chinese Academy of Sciences under

Abstract

We present an experimental determination on the Landé g-factors for the 5s2 1S0 and 5s5p 3P0 states in ultra-cold atomic systems, which is important for evaluating the Zeeman shift of the clock transition in the 87Sr optical lattice clock. The Zeeman shift of the 5s5p 3P0–5s2 1S0 forbidden transition is measured with the π-polarized and σ±-polarized interrogations at different magnetic field strengths. Moreover, in the g-factor measurement with the σ±-transition spectra, it is unnecessary to calibrate the external magnetic field. By this means, the ground state 5s2 1S0 g-factor for the 87Sr atom is −1.306(52)×10−4, which is the first experimental determination to the best of our knowledge, and the result matches very well with the theoretical estimation. The differential g-factor δg between the 5s5p 3P0 state and the 5s2 1S0 state of the 87Sr atoms is measured in the experiment as well, which are −7.67(36) × 10−5 with π-transition spectra and −7.72(43) × 10−5 with σ±-transition spectra, in good agreement with the previous report [Phys. Rev. A 76 (2007) 022510]. This work can also be used for determining the differential g-factor of the clock states for the optical clocks based on other atoms.