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Reduction of light shifts in Ramsey spectroscopy with a combined error signal



Moshe Shuker, Juniper Wren Y. Pollock, Rodolphe Boudot, V. I. Yudin, A. V. Taichenachev, John E. Kitching, Elizabeth A. Donley


Light-induced frequency shifts can be a key limiting contribution to the mid and long-term frequency stability in atomic clocks. In this letter, we demonstrate the experimental implementation of the combined error signal (CES) interrogation protocol to a cold atom clock based on coherent population trapping (CPT) and Ramsey spectroscopy. The CES method is based on the use of a single error signal that results from the normalized combination of two error signals extracted from two Ramsey sequences of different dark periods. This combined error signal is used to stabilize the atomic clock frequency. Compared to the standard Ramsey-CPT interrogation, this method reduces the clock frequency sensitivity to the intensity ratio of the CPT fields and CPT laser frequency variations by more than an order of magnitude. This method can be applied in various kinds of Ramsey-based atomic clocks, sensors and instruments.
Applied Physics Letters


atomic clock, laser cooling, light-shifts, Ramsey spectroscopy


Shuker, M. , Y., J. , Boudot, R. , Yudin, V. , Taichenachev, A. , Kitching, J. and Donley, E. (2019), Reduction of light shifts in Ramsey spectroscopy with a combined error signal, Applied Physics Letters, [online], (Accessed April 20, 2024)
Created April 11, 2019, Updated October 7, 2019