Spin dependent inelastic collisions between metastable state two-electron atoms and ground state alkali-atoms

Abstract

Experimentally the spin dependence of inelastic collisions between ytterbium (Yb) in the metastable ${}^{3}{{\rm{P}}}_{2}$ state and lithium (Li) in the ${}^{2}{{\rm{S}}}_{1/2}$ ground state manifold is investigated at low magnetic fields. Using selective excitation all magnetic sublevels m _J of ${}^{174}$ Yb( ${}^{3}{{\rm{P}}}_{2}$ ) are accessed and four of the six lowest lying magnetic sublevels of ${}^{6}{\rm{L}}{\rm{i}}$ are prepared by optical pumping. On the one hand, m _J -independence of collisions involving Li( $F=1/2$ ) atoms is found. A systematic m _J -dependence in collisions with Li( $F=3/2$ ) atoms, in particular suppressed losses for stretched collisional states, is observed on the other hand. Further, m _J -changing processes are found to be of minor relevance. The span of observed inelastic collision rates is between $1\times {10}^{-11}$ and $40\times {10}^{-11}\,{\mathrm{cm}}^{3}\,{{\rm{s}}}^{-1}$ , and a possible origin of the observed behavior is discussed.

Keywords

• quantum degenerate atomic mixtures
• metastable state
• inelastic collisions
• non-S-state collisions
• anisotropy