Measurement of the temperature dependence of dwell time and spin relaxation probability of Rb atoms on paraffin surfaces using a beam-scattering method

Kanta Asakawa; Yutaro Tanaka; Kenta Uemura; Norihiro Matsuzaka; Kunihiro Nishikawa; Yuki Oguma; Hiroaki Usui; Atsushi Hatakeyama

doi:10.1103/physreva.104.063106

arXiv · 2108.04487

Measurement of the temperature dependence of dwell time and spin relaxation probability of Rb atoms on paraffin surfaces using a beam-scattering method

Kanta Asakawa·Yutaro Tanaka·Kenta Uemura·Norihiro Matsuzaka·Kunihiro Nishikawa·Yuki Oguma·Hiroaki Usui·Atsushi Hatakeyama

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Abstract

The scattering of Rb atoms on an anti-relaxation coating was studied. No significant change in the spin relaxation probability of Rb atoms by single scattering from a tetracontane surface was observed by cooling the film from 305 to 123 K. The mean surface dwell time was estimated using a time-resolved method.Delay-time spectra, from which mean surface dwell times can be estimated, were measured at 305, 153, and 123 K, with a time window of $9.3\times 10^{-5}$ s. The increase in mean surface dwell time with cooling from 305 to 123 K was smaller than $4.4\times 10^{-6}$ s, which is significantly smaller than the value expected from the mean dwell time at room temperature measured using the Larmor frequency shift. These results can be explained by assuming a small number of scattering components, with a mean surface dwell time at least three orders of magnitude longer than the majority component.

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Kanta Asakawa, Yutaro Tanaka, Kenta Uemura, Norihiro Matsuzaka, Kunihiro Nishikawa, Yuki Oguma, Hiroaki Usui, Atsushi Hatakeyama. 2021-08-10. Measurement of the temperature dependence of dwell time and spin relaxation probability of Rb atoms on paraffin surfaces using a beam-scattering method. https://doi.org/10.1103/physreva.104.063106

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