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High-Performance Coherent Population Trapping Clock Based on Laser-Cooled Atoms



Xiaochi Liu, Eugene Ivanov, V. I. Yudin, John Kitching, Elizabeth Donley


Atomic clocks based on laser-cooled atoms are capable of achieving long interrogation periods and hence narrow resonance linewidths because of the very low atom velocities achievable with laser cooling. The long interrogation periods are achieved without the frequency shifts and resulting instabilities that come from the addition of buffer gases, which are usually used for vapor-cell clocks to extend the interrogation period. Here we present a cold-atom coherent population trapping clock that achieves fractional frequency stability at the level of 3×10^-13 on the timescale of an hour. This level of stability is an order of magnitude better than the best CPT clocks reported for vapor-cells on that time scale.
Physical Review Applied


atomic clock, coherent population trapping, light shifts, ramsey spectroscopy


Liu, X. , Ivanov, E. , Yudin, V. , Kitching, J. and Donley, E. (2017), High-Performance Coherent Population Trapping Clock Based on Laser-Cooled Atoms, Physical Review Applied, [online], (Accessed June 21, 2024)


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Created November 1, 2017, Updated October 12, 2021