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arXiv · 2211.09015

Measurement of Doppler effects in cryogenic buffer-gas cell

Ayami Hiramoto·Masaaki Baba·Katsunari Enomoto·Kana Iwakuni·Susumu Kuma·Yuiki Takahashi·Reo Tobaru·Yuki Miyamoto
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Abstract

Buffer-gas cooling is a universal cooling technique for molecules and used for various purposes. One of its applications is using molecules inside a buffer-gas cell for low-temperature spectroscopy. Although a high-intensity signal is expected in the cell, complex molecular dynamics is a drawback for precise spectroscopy. In this study, we performed high-resolution absorption spectroscopy of low-J transitions in the $\tilde{A}^2\Pi (0,0,0)-\tilde{X}^2\Sigma ^+(0,0,0)$ band of calcium monohydroxide (CaOH). CaOH molecules were produced by laser ablation in a copper cell and cooled to $\sim$5\,K using helium buffer gas. We probed the Doppler effects in a buffer-gas cell by injecting counter-propagating lasers inside the cell. The time evolutions of the Doppler width and shift were simulated using a dedicated Monte Carlo simulation and compared with data.

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Ayami Hiramoto, Masaaki Baba, Katsunari Enomoto, Kana Iwakuni, Susumu Kuma, Yuiki Takahashi, Reo Tobaru, Yuki Miyamoto. 2022-11-16. Measurement of Doppler effects in cryogenic buffer-gas cell. https://doi.org/10.1103/physreva.107.043114

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