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arXiv · 2110.02466

Magnetic-field-insensitive coherent-population-trapping resonances excited by bichromatic linearly polarized fields on the $D_1$ line of $^{133}$Cs

K. Matsumoto·S. Kagami·A. Kirihara·S. Yanagimachi·T. Ikegami·A. Morinaga
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Abstract

We have experimentally demonstrated that magnetic-field-insensitive coherent-population-trapping (CPT) resonances are generated between the ground hyperfine levels on the $D_1$ line of $^{133}$Cs using a two-photon $\Lambda$ scheme excited by lin || lin polarizations. The frequency shift of the CPT resonance is 0.04 Hz for the deviation of 1 $\mu$T at a "magic" magnetic field of 139 $\mu$T and is 50 times smaller than that of the conventional clock transition at a typical bias magnetic field for the clock operation. The amplitude of the CPT spectrum excited by lin || lin polarizations is enhanced as the excitation intensity increases and is well explained by the three-level model without trap levels. Thus, the CPT resonance on the $D_1$ line of $^{133}$Cs atom excited by a simple lin || lin scheme will be one of the best candidates for frequency reference of miniature atomic clocks.

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K. Matsumoto, S. Kagami, A. Kirihara, S. Yanagimachi, T. Ikegami, A. Morinaga. 2021-10-06. Magnetic-field-insensitive coherent-population-trapping resonances excited by bichromatic linearly polarized fields on the $D_1$ line of $^{133}$Cs. https://doi.org/10.1103/physreva.105.023110

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