A CPT-based Cs vapor cell atomic clock with a short-term fractional frequency stability of 3 x 10-13 τ-1/2

8th Symposium on Frequency Standards and Metrology 2015

Hafiz, Moustafa Abdel^1 ; Liu, Xiaochi^1,3 ; Guérandel, Stéphane^2 ; De Clercq, Emeric^2 ; Boudot, Rodolphe^1

FEMTO-ST, CNRS, UFC, 26 chemin de l'épitaphe, Besançon Cedex

25030, France^1

LNE-SYRTE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, 61 avenue de l'Observatoire, Paris

75014, France^2

National Institute of Standards and Technology (NIST), Boulder

CO

80305, United States^3

关键词: Averaging time;    Clock transition;    Coherent population trapping;    Fractional frequencies;    High contrast;    Light-pulse sequence;    Pumping techniques;    Ramsey fringes;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/723/1/012013/pdf
DOI  :  10.1088/1742-6596/723/1/012013

来源: IOP

【 摘 要 】

This article reports on the development and short-term fractional frequency stability of a continuous-regime (CW) Cs vapor cell atomic clock based on coherent population trapping (CPT). The push-pull optical pumping technique is used to increase the number of atoms that participate to the clock transition, yielding a typical CPT resonance contrast of 25% for a CPT linewidth of about 450 Hz. The clock short-term fractional frequency stability is measured to be 3 x 10-13τ-1/2up to 100 seconds averaging time, in correct agreement with the signal-to-noise ratio limit. The mid-term frequency stability results are currently mainly limited by laser power effects. The detection of high-contrast narrow Raman-Ramsey fringes is demonstrated with this setup by making the atoms interact with a light pulse sequence.