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arXiv · 2410.06116

Faraday-Ramsey rotation measurement in a thin cell as an analogy to an atomic beam

Mark Dikopoltsev·Eliran Talker·Yefim Barash·Noa Mazurski·Uriel Levy
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Abstract

Atomic beams are powerful tools for measuring spin coherence in hot vapors but require bulky setups, limiting device miniaturization. We demonstrate that micron-thin vapor cells can mimic atomic beam behavior by exploiting geometry-dependent velocity filtering. In a 5 {\mu}m rubidium cell, coherence is preserved for atoms moving parallel to the cell walls, enabling observation of the Faraday-Ramsey effect without buffer gas or anti-relaxation coatings. Using a spatially displaced pump-probe scheme and magnetic field scanning, we achieve clear Ramsey fringes and validate our model experimentally. This technique offers a compact alternative to atomic beam systems, supporting scalable sensors and frequency standards.

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Mark Dikopoltsev, Eliran Talker, Yefim Barash, Noa Mazurski, Uriel Levy. 2024-10-08. Faraday-Ramsey rotation measurement in a thin cell as an analogy to an atomic beam. https://arxiv.org/abs/2410.06116

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