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arXiv:1311.4352 · Physical Review A

Inelastic collisions of optically trapped metastable calcium atoms

Purbasha Halder, Hannes Winter, Andreas Hemmerich

Published Dec 26, 2013• 6 citations
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Abstract

We study binary collisions of metastable calcium atoms (${}^{40}$Ca) in an optical dipole trap. Collisions between ${}^{3}{P}_{0}$ atoms and between ${}^{3}{P}_{0}$ and ${}^{1}{S}_{0}$ atoms are considered. In the former case, the elastic and inelastic collision parameters are found to be $5.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}$ and $3.6\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}\phantom{\rule{0.16em}{0ex}}\phantom{\rule{0.16em}{0ex}}{\mathrm{cm}}^{3}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$, respectively. A fraction of the collisions between ${}^{3}{P}_{0}$ atoms is found to produce cold trapped atoms in the singlet ${}^{1}{S}_{0}$ state, suggesting that the internal energy for these collisions is dissipated by radiation. For collisions between ${}^{3}{P}_{0}$ and ${}^{1}{S}_{0}$ atoms, we find a two-body loss parameter of $8.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}\phantom{\rule{0.16em}{0ex}}\phantom{\rule{0.16em}{0ex}}{\mathrm{cm}}^{3}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$. Our observations show that metastable calcium samples in the ${}^{3}{P}_{0}$ state are not stable at high densities, which limits their usefulness in quantum computing or many-body quantum simulation schemes.

DOI
10.1103/physreva.88.063639

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