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arXiv · 2203.13580

Spectroscopy of high pressure rubidium-noble gas mixtures

Till Ockenfels·Paško Roje·Thilo vom Hövel·Frank Vewinger·Martin Weitz
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Abstract

Spectroscopy of alkali-buffer gas mixtures at high pressures from single-digit to several 100 bars in the regime of substantial collisional broadening is relevant in a wide range of fields, ranging from collisional redistribution cooling to laboratory astrophysics. Here we report on spectroscopic measurements of dense rubidium-noble gas mixtures recorded in a pressure cell equipped with soldered sapphire optical viewports, which allows for the controlled realization of extreme conditions of high temperature and high pressure in a table top laboratory experiment. In the gas cell, we have recorded absorption and emission spectra of rubidium subject to 250 bar helium buffer gas pressure at 500 K temperature. The spectra to good accuracy fulfill the thermodynamic Kennard- Stepanov frequency scaling of the ratio of absorption and emission spectral profiles. Further, the long optical path length in the cell allowed to both record spectra of rubidium-argon mixtures at moderate temperatures and high pressures and to observe redistributional laser cooling in this system.

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Till Ockenfels, Paško Roje, Thilo vom Hövel, Frank Vewinger, Martin Weitz. 2022-03-25. Spectroscopy of high pressure rubidium-noble gas mixtures. https://doi.org/10.1103/physreva.106.012815

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