# Collision-Induced Spin Exchange of Alkali-Metal Atoms With $$^3$$He: An Ab Initio Study

 Title: Collision-Induced Spin Exchange of Alkali-Metal Atoms With $$^3$$He: An Ab Initio Study Author: Tscherbul, T.V.; Zhang, P.; Sadeghpour, Hossein R.; Dalgarno, Alexander Note: Order does not necessarily reflect citation order of authors. Citation: Tscherbul, T.V., P. Zhang, Hossein R. Sadeghpour, and Alexander Dalgarno. 2009. Collision-induced spin exchange of alkali-metal atoms with $$^3$$He: An ab initio study. Physical Review A 79(6): 062707. Full Text & Related Files: PhysRevA.79.062707.pdf (360.3Kb; PDF) Abstract: We present a rigorous quantum study of spin-exchange transitions in collisions of the alkali-metal atoms with $$^3$$He in the presence of an external magnetic ﬁeld. Using accurate ab initio interaction potentials, we obtain reﬁned estimates for the Fermi contact interaction constants for complexes of Na, K, and Rb atoms with $$^3$$He. Ab initio calculations show that the Fermi contact interaction in Li-$$^3$$He varies more slowly with inter-nuclear distance than predicted by the atomic model [R. M. Herman, Phys. Rev. 37, A1062 (1965)]. The calculated spin-exchange rate constants for Na, K, and Rb atoms in a gas of $$^3$$He are in good agreement with experimental data. Our calculations demonstrate that at a temperature of 0.5 K, collision-induced spin exchange of the alkali-metal atoms occurs at a very slow rate of ~10$$^−22$$ cm$$^3$$/s, suggesting potential applications in cryogenic cooling, precision spectroscopy, and quantum optics. Published Version: doi:10.1103/PhysRevA.79.062707 Terms of Use: This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAA Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:10345124 Downloads of this work:

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