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arXiv:2005.09102 · Physical Review A

Interaction potentials and ultracold scattering cross sections for the Li+7–Li7 ion-atom system

Amrendra Pandey, M. Niranjan, N. Joshi, S. A. Rangwala, Romain Véxiau, Olivier Dulieu

Published May 11, 2020• 10 citations
arXivHTMLPDF

Abstract

We calculate the isotope-independent ${\mathrm{Li}}^{+}$-Li potential energy curves for the electronic ground and first excited states. The scattering phase shifts and total scattering cross section for the $^{7}\mathrm{Li}^{+}\text{\ensuremath{-}}^{7}\mathrm{Li}$ collision are calculated, with an emphasis on the ultralow-energy domain down to the $s$-wave regime. The effect of physically motivated alterations on the calculated potential energy curves is used to determine the bound of accuracy of the low-energy scattering parameters for the ion-atom system. It is found that the scattering length for the $A{\phantom{\rule{0.16em}{0ex}}}^{2}{\mathrm{\ensuremath{\Sigma}}}_{u}^{+}$ state, ${a}_{u}=1325{a}_{0}$, is positive and has well-constrained bounds. For the $X{\phantom{\rule{0.16em}{0ex}}}^{2}{\mathrm{\ensuremath{\Sigma}}}_{g}^{+}$ state, the scattering length, ${a}_{g}=20\phantom{\rule{0.16em}{0ex}}465{a}_{0}$, has a large magnitude, as it is sensitive to the restrained change of the potential, due to the presence of a vibrational state in the vicinity of the dissociation limit.

DOI
10.1103/physreva.101.052702

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