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arXiv · 1012.5433

Sub-Doppler Laser Cooling of Thulium Atoms in a Magneto-optical Trap

D. Sukachev·A. Sokolov·K. Chebakov·A. Akimov·S. Kanorsky·N. Kolachevsky·V. Sorokin
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Abstract

We have experimentally studied sub-Doppler laser cooling in a magneto-optical trap for thulium atoms working at the wavelength of 410.6\,nm. Without any dedicated molasses period of sub-Doppler cooling, the cloud of $3\times 10^6$ atoms at the temperature of 25(5)\,$\mu$K was observed. The measured temperature is significantly lower than the Doppler limit of 240$\mu$K for the cooling transition at 410.6\,nm. High efficiency of the sub-Doppler cooling process is due to a near-degeneracy of the Land\'e-$g$ factors of the lower $4f^{13}6s^{2}\, (J\,=\,{7}/{2})$ and the upper $4f^{12}5d_{3/2}6s^{2}\, (J\,=\,{9}/{2})$ cooling levels.}

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D. Sukachev, A. Sokolov, K. Chebakov, A. Akimov, S. Kanorsky, N. Kolachevsky, V. Sorokin. 2010-12-24. Sub-Doppler Laser Cooling of Thulium Atoms in a Magneto-optical Trap. https://doi.org/10.1134/s0021364010220133

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