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arXiv:1906.05756 · Physical Review A

In situ Raman gain between hyperfine ground states in a potassium magneto-optical trap

Graeme Harvie, Adam Butcher, J. Goldwin

Published Sep 9, 2019• 4 citations
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Abstract

We study optical gain in a gas of cold $^{39}\mathrm{K}$ atoms. The gain is observed during operation of a conventional magneto-optical trap without the need for additional fields. Measurements of transmission spectra from a weak probe show that the gain is due to stimulated Raman scattering between hyperfine ground states. The experimental results are reproduced by a simplified six-level model, which also helps explain why such gain is not observed in similar experiments with rubidium or cesium.

DOI
10.1103/physreva.100.033408

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We study optical gain in a gas of cold 39K^{39}\mathrm{K}39K atoms. The gain is observed during operation of a conventional magneto-optical trap without the need for additional fields. Measurements of transmission spectra from a weak probe show that the gain is due to stimulated Raman scattering between hyperfine ground states. The experimental results are reproduced by a simplified six-level model, which also helps explain why such gain is not observed in similar experiments with rubidium or cesium.
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