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Light shifts in a pulsed cold-atom coherent-population-trapping clock



Eric M. Blanshan, Elizabeth A. Donley, John E. Kitching


Field-grade atomic clocks capable of primary standard performance in compact physics packages would be of significant value in a variety of applications. A cold-atom coherent population trapping clock featuring laser-cooled 87Rb atoms and pulsed Ramsey interrogation is a strong candidate for this technology if the frequency biases can be minimized and controlled. Here we characterize the AC-stark effect in the lin I I lin CPT scheme, explaining observed light shifts in terms of contributions from coherent CPT-generating couplings and optical-pumping effects caused by incoherent light. Measurements are compared with existing and new theoretical treatments, and a laser configuration is identified that reduces clock drift from light shifts to -14 for the current system.
Physical Review Letters


Atomic clocks, coherent population trapping, laser-cooled atoms


Blanshan, E. , Donley, E. and Kitching, J. (2015), Light shifts in a pulsed cold-atom coherent-population-trapping clock, Physical Review Letters, [online], (Accessed July 21, 2024)


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Created April 10, 2015, Updated November 10, 2018