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arXiv · 2504.19713

Measurement of the total spin angular momentum of alkali-metal atoms

Runa Yasuda·Kei Ishii·Wolfgang Klassen·Jeffery W. Martin·Atsushi Hatakeyama
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Abstract

It is important to evaluate the total spin angular momentum of alkali-metal atoms if the atoms serve as a reservoir of angular momenta. We use an absorption-monitoring technique to measure , i.e., the expectation values of the quantization (z) axis components of the total angular momentum of cesium (Cs) atoms in the electronic ground state in both uncoated and anti-relaxation-coated vacuum cells at room temperature. Cs atoms are polarized via optical pumping and probed using their D2 transitions. The probe laser frequency is varied across the Doppler-broadened D2 transition; the values are derived using the integrated absorption coefficients. The largest is 2.5 for the coated cell. We then use a simple model of spin flow through vapor cells to estimate the atomic spin relaxation probabilities after a single surface collision.

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Runa Yasuda, Kei Ishii, Wolfgang Klassen, Jeffery W. Martin, Atsushi Hatakeyama. 2025-04-28. Measurement of the total spin angular momentum of alkali-metal atoms. https://doi.org/10.1103/physreva.111.033111

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