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arXiv:1806.10346 · Physical Review A

Proposal for the formation of ultracold deeply bound RbSr dipolar molecules by all-optical methods

Adrien Devolder, Eliane Luc-Koenig, Osman Atabek, Michèle Desouter-Lecomte, Olivier Dulieu

Published Nov 9, 2018• 14 citations
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Abstract

Ultracold paramagnetic and polar diatomic molecules are among the promising systems for quantum simulation of lattice-spin models. Unfortunately, their experimental observation is still challenging. Based on our recent ab initio calculations, we analyze the feasibility of all-optical schemes for the formation of ultracold $^{87}\mathrm{Rb}^{84}\mathrm{Sr}$ bosonic molecules. A first possibility is photoassociation followed by spontaneous emission. The photoassociation rate coefficients toward electronic states converging to the $^{87}\mathrm{Rb}(5s\phantom{\rule{0.16em}{0ex}}^{2}S_{1/2})+^{84}\mathrm{Sr}(5s5p\phantom{\rule{0.16em}{0ex}}^{3}P_{0,1,2}$) asymptotes are particularly small for vibrational levels close to the asymptote. The creation of molecules would be more interesting by using deeply bound levels which preferentially relax to the ${v}^{\ensuremath{'}\ensuremath{'}}=0$ level of the ground state. On the other hand, the photoassociation rate coefficients toward electronic states correlated to the $\mathrm{Rb}(5p\phantom{\rule{0.16em}{0ex}}^{2}P_{1/2,3/2})+\mathrm{Sr}(5{s}^{2}\phantom{\rule{0.16em}{0ex}}^{1}S_{0}$) are significant for levels close to the asymptote. The spontaneous emission thus creates weakly bound molecules in a single vibrational level. A second option relies on stimulated Raman adiabatic passage implemented in a tight optical trap. It efficiently creates weakly bound ground-state molecules in a well-defined level, thus providing a promising alternative to magnetic Feshbach resonances for further population transfer toward the absolute ground state of the RbSr molecule.

DOI
10.1103/physreva.98.053411

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