Large spin relaxation rates in trapped submerged-shell atoms

• Main Authors: Connolly, Colin B. (Contributor), Au, Yat Shan (Contributor), Doret, S. Charles (Contributor), Ketterle, Wolfgang (Contributor), Doyle, John M. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Physics (Contributor), MIT-Harvard Center for Ultracold Atoms (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society, 2010-07-12T15:08:56Z.
• Subjects: Article
• Online Access: Get fulltext

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 3.0×10[superscript -10] and 1.1×10[superscript -10] cm[superscript 3] s[superscript -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, electronic interaction 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.
National Science Foundation (Grant No. 0757157)
Harvard/MIT Center for Ultracold Atoms