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Active light-shift stabilization in modulated CPT clocks



V Shah, P Schwindt, Vladislav Gerginov, Svenja A. Knappe, Leo W. Hollberg, John E. Kitching


We demonstrate a simple technique to significantly improve the long-term frequency stability in atomic clocks based on coherent population trapping (CPT). In this technique an additional servo is used to control the local oscillator power level to ensure that the clock frequency is always given by the atomic resonance frequency that is not perturbed by the incident light fields.
Proceedings Title
Proc. Freq. Cont. Symp
Conference Dates
June 5-7, 2006
Conference Location
Miami, FL
Conference Title
IEEE Intl. Freq. Cont. Symp.


Coherent Population trapping, Frequency Standards, Light shifts


Shah, V. , Schwindt, P. , Gerginov, V. , Knappe, S. , Hollberg, L. and Kitching, J. (2006), Active light-shift stabilization in modulated CPT clocks, Proc. Freq. Cont. Symp, Miami, FL, [online], (Accessed July 25, 2024)


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Created June 5, 2006, Updated February 17, 2017