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arXiv:1501.00884 · Physical Review A

Ab initiointeraction potentials and scattering lengths for ultracold mixtures of metastable helium and alkali-metal atoms

Dariusz Kędziera, Ł. M. Mentel, Piotr Szymon Żuchowski, Steven Knoop

Published Jun 25, 2015• 7 citations
arXivHTMLPDF

Abstract

We have obtained accurate ab initio $^{4}\mathrm{\ensuremath{\Sigma}}^{+}$ quartet potentials for the diatomic metastable triplet helium+alkali-metal (Li, Na, K, Rb) systems, using all-electron restricted open-shell coupled cluster singles and doubles with noniterative triples corrections CCSD(T) calculations and accurate calculations of the long-range ${C}_{6}$ coefficients. These potentials provide accurate ab initio quartet scattering lengths, which for these many-electron systems is possible, because of the small reduced masses and shallow potentials that result in a small amount of bound states. Our results are relevant for ultracold metastable triplet helium+alkali-metal mixture experiments.

DOI
10.1103/physreva.91.062711

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