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arXiv · 2407.00841

Short-term stability of a microcell optical reference based on Rb atom two-photon transition at 778 nm

Abstract

We report on the development and short-term stability characterization of an optical frequency reference based on the spectroscopy of the rubidium two-photon transition at 778 nm in a microfabricated vapor cell. When compared against a 778 nm reference signal extracted from a frequency-doubled cavity-stabilized telecom laser, the short-term stability of the microcell frequency standard is 3.5 $\times$ 10$^{-13}$ $\tau^{-1/2}$ until 200~s, in good agreement with a phase noise level of $+$ 43 dBrad$^2$/Hz at 1~Hz offset frequency. The two main contributions to the short-term stability of the microcell reference are currently the photon shot noise and the intermodulation effect induced by the laser frequency noise. With still a relevant margin of progress, these results show the interest of this spectroscopic approach for the demonstration of high-stability miniaturized optical vapor cell clocks. Such clocks are poised to be highly beneficial for applications in navigation, communications, and metrology.

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Martin Callejo, Andrei Mursa, Rémy Vicarini, Emmanuel Klinger, Quentin Tanguy, Jacques Millo, Nicolas Passilly, Rodolphe Boudot. 2024-06-30. Short-term stability of a microcell optical reference based on Rb atom two-photon transition at 778 nm. https://arxiv.org/abs/2407.00841

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