IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control

Frequency Shifts in a Coherent Population Trapping Cs Vapor Cell Atomic Clock

Juliette Breurec, Moustafa Abdel Hafiz, Claudio Eligio Calosso, O. Lelievre, Rodolphe Boudot

Published May 29, 2025• 4 citations

Abstract

We report on measurements of frequency shifts in a microwave cesium vapor cell atomic clock based on coherent population trapping (CPT). The dependence of the clock frequency on numerous experimental parameters, such as the laser power, the laser frequency, the microwave power, the cell temperature, the static magnetic field, but also the temperature of some key components, or the translation and rotation of critical wave plates and optical elements, is investigated. The stability budget of the clock frequency at one day is reported and discussed. This study constitutes a solid database for the future demonstration of a CPT-based cell clock with enhanced mid- and long-term stability performances.

DOI: 10.1109/tuffc.2025.3575002

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