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

TL;DR

This paper presents accurate ab initio interaction potentials and scattering lengths for ultracold mixtures of metastable helium with alkali-metal atoms, aiding experimental research in ultracold physics.

Contribution

The study provides the first accurate ab initio quartet potentials and scattering lengths for metastable helium and alkali-metal atom systems using advanced coupled cluster calculations.

Findings

Generated accurate quartet potentials for He + alkali-metal systems.

Calculated precise scattering lengths relevant for ultracold experiments.

Results facilitate understanding of ultracold metastable helium-alkali mixtures.

Abstract

We have obtained accurate ab initio 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 results in a small amount of bound states. Our results are relevant for ultracold metastable triplet helium + alkali-metal mixture experiments.