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arXiv · 0909.0249

Large spin relaxation rates in trapped submerged-shell atoms

Colin B. Connolly·Yat Shan Au·S. Charles Doret·Wolfgang Ketterle·John M. Doyle
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Abstract

Spin relaxation due to atom-atom collisions is measured for magnetically trapped erbium and thulium atoms at a temperature near 500 mK. The rate constants for Er-Er and Tm-Tm collisions are 3.0 times 10^-10 cm^3 s^-1 and 1.1 times 10^-10 cm^3 s^-1, respectively, 2-3 orders of magnitude larger than those observed for highly magnetic S-state atoms. This is strong evidence for an additional, dominant, spin relaxation mechanism, electrostatic anisotropy, in collisions between these "submerged-shell" L > 0 atoms. These large spin relaxation rates imply that evaporative cooling of these atoms in a magnetic trap will be highly inefficient.

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Colin B. Connolly, Yat Shan Au, S. Charles Doret, Wolfgang Ketterle, John M. Doyle. 2009-09-01. Large spin relaxation rates in trapped submerged-shell atoms. https://doi.org/10.1103/physreva.81.010702

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