Conference on Precision Electromagnetic Measurements

Operating atomic fountain clock using robust DBR laser system

Sangmin Lee, Myoung-Sun Heo, Taeg Yong Kwon, Hyun-Gue Hong, Sang-Bum Lee, John Gideon Hartnett, Sang Eon Park

Published Jul 1, 2016• 2 citations

Abstract

We operate an atomic fountain clock KRISS-F1 using a laser system based on a DBR (Distributed Bragg Reflector) laser. We have found that there is no major difference in the fountain performance between laser systems with an ECDL (Extended-Cavity Diode Laser) and the DBR laser, even though spectral properties of the DBR is worse than that of ECDL. Moreover, quantum projection-noise limited stability is observed using DBR lasers. After replacing the ECDL to the DBR laser, laser system of the fountain clock became robust against acoustic and vibration noise mainly from mechanical shutters. Therefore, currently KRISS-F1 can be operated without failure of laser locking.

DOI: 10.1109/cpem.2016.7540697

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