Abstract
Miniature atomic clocks based on coherent population trapping (CPT) states in thermal atoms are an important component in many field applications, particularly where satellite frequency standards are not accessible. Cold-atom CPT clocks promise improved accuracy and stability over existing commercial technologies. Here we demonstrate a cold-atom CPT clock based on Rb using a high-contrast double- configuration. Doppler frequency shifts are explained using a simple model and canceled by interrogating the atoms with counterpropagating light beams. We realize a compact cold-atom CPT clock with a fractional frequency stability of , thus demonstrating the potential of these devices. We also show that the long-term stability is currently limited by the second-order Zeeman shift to at 1000 s.
- Received 29 May 2013
DOI:https://doi.org/10.1103/PhysRevA.88.042120
©2013 American Physical Society