Light shift in CPT based Cs miniature atomic clocks

We report on our studies of the light shift in a miniature atomic clock based on Coherent Population Trapping (CPT) in Cesium. There is no data published in the literature on the frequency and intensity-related light shift coefficients for CPT atomic clock on the Cesium D₁ line, only for the D₂ line. With our data we fill this gap and report on the measurements of light shift for the Cs D₁ line in a MEMS buffer-gas cell. The behavior of the light shift due to different laser intensities, laser frequencies and due to different cell temperatures is discussed.