Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Cold-atom double-lambda coherent population trapping clock



Elizabeth A. Donley, Francois-Xavier R. Esnault, Eric M. Blanshan, Eugene N. Ivanov, Robert E. Scholten, John E. Kitching


Miniature atomic clocks based on coherent population trapping (CPT) states in thermal atoms are emerging as an important component in many field applications, particularly where satellite frequency standards are not accessible. Cold-atom CPT clocks promise improved accuracy and stability. Here we demonstrate a cold-atom CPT clock using a high-contrast double-lambda CPT configuration. Doppler frequency shifts are explained using a simple model and canceled by interro- gating the atoms with counterpropagating light beams. We realize a compact cold-atom CPT clock with a fractional frequency stability of 4 x 10-11/√τ, thus demonstrating the promise of these devices. We also show that the long-term stability is currently limited by the second-order Zeeman shift to 2x10-12 at 1000s.
Physical Review A


Atomic Clocks, Coherent Population Trapping, Doppler Shift


Donley, E. , Esnault, F. , Blanshan, E. , Ivanov, E. , E., R. and Kitching, J. (2013), Cold-atom double-lambda coherent population trapping clock, Physical Review A, [online], (Accessed May 28, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created October 31, 2013, Updated February 19, 2017