Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS)

High contrast signal in a coherent population trapping based atomic frequency standard application

M. Zhu

Published Jul 8, 2004• 27 citations

Publisher

Abstract

A polarization-selective method is developed for detecting a coherent-population-trapping (CPT) resonance signal in a vapor cell. The method uses a single laser beam with frequency modulation to induce CPT resonance and to control the AC Stark shift. The method provides a CPT resonance signal with a high contrast of 22%. Using this method, a CPT-based rubidium vapor cell frequency standard demonstrates a measured short-term stability of 1.4/spl times/10/sup -12//spl tau//sup - 1/2 /.

DOI: 10.1109/freq.2003.1274978

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