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arXiv:1701.07924 · Physical Review A

Light-assisted collisions in ultracold Tm atoms

I. S. Cojocaru, Sergey Pyatchenkov, Stepan Snigirev, I. A. Luchnikov, Елена Сергеевна Калганова, Gulnara A. Vishnyakova, Daria N. Kublikova, Vladislav Bushmakin, E. T. Davletov, V. V. Tsyganok, O. V. Belyaeva, А. Хорошилов, В. Н. Сорокин, Денис Дмитриевич Сукачев, Alexey V. Akimov

Published Jan 25, 2017• 16 citations
arXivHTMLPDF

Abstract

We studied light-assisted collisions of Tm atoms in a magneto-optical trap (MOT), working on a weak cooling transition at 530.7 nm [$4{f}^{13}(^{2}F^{o})6{s}^{2},\phantom{\rule{0.16em}{0ex}}J=7/2,\phantom{\rule{0.16em}{0ex}}F=4$ to $4{f}^{12}(^{3}H_{6})5{d}_{5/2}6{s}^{2},\phantom{\rule{0.16em}{0ex}}J=9/2,\phantom{\rule{0.16em}{0ex}}F=5$]. We observed a strong influence from radiation trapping and light-assisted collisions on the dynamics of this trap. We carefully separated these two contributions and measured the binary loss rate constant at different laser powers and detuning frequencies near the cooling transition. Analyzing losses from the MOT, we found the light-assisted inelastic binary loss rate constant to reach values of up to $\ensuremath{\beta}={10}^{\ensuremath{-}9}\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{3}/\mathrm{s}$ and gave the upper bound on a branching ratio $k<0.8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$ for the 530.7 nm transition.

DOI
10.1103/physreva.95.012706

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We studied light-assisted collisions of Tm atoms in a magneto-optical trap (MOT), working on a weak cooling transition at 530.7 nm [4f13(2Fo)6s2,J=7/2,F=44{f}^{13}(^{2}F^{o})6{s}^{2},\phantom{\rule{0.16em}{0ex}}J=7/2,\phantom{\rule{0.16em}{0ex}}F=44f13(2Fo)6s2,J=7/2,F=4 to 4f12(3H6)5d5/26s2,J=9/2,F=54{f}^{12}(^{3}H_{6})5{d}_{5/2}6{s}^{2},\phantom{\rule{0.16em}{0ex}}J=9/2,\phantom{\rule{0.16em}{0ex}}F=54f12(3H6​)5d5/2​6s2,J=9/2,F=5]. We observed a strong influence from radiation trapping and light-assisted collisions on the dynamics of this trap. We carefully separated these two contributions and measured the binary loss rate constant at different laser powers and detuning frequencies near the cooling transition. Analyzing losses from the MOT, we found the light-assisted inelastic binary loss rate constant to reach values of up to \ensuremathβ=10\ensuremath−9cm3/s\ensuremath{\beta}={10}^{\ensuremath{-}9}\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{3}/\mathrm{s}\ensuremathβ=10\ensuremath−9cm3/s and gave the upper bound on a branching ratio k<0.8\ifmmode×\else\texttimes\fi10\ensuremath−6k<0.8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}k<0.8\ifmmode×\else\texttimes\fi10\ensuremath−6 for the 530.7 nm transition.
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