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arXiv:1509.05390 · Physical Review A

Ultracold magnetically tunable interactions without radiative-charge-transfer losses between Ca+, Sr+, Ba+ , and Yb+ ions and Cr atoms

Michał Tomza

Published Dec 1, 2015• 20 citations
arXivHTMLPDF

Abstract

The ${\mathrm{Ca}}^{+}, {\mathrm{Sr}}^{+}, {\mathrm{Ba}}^{+}$, and ${\mathrm{Yb}}^{+}$ ions immersed in an ultracold gas of the Cr atoms are proposed as experimentally feasible heteronuclear systems in which ion-atom interactions at ultralow temperatures can be controlled with magnetically tunable Feshbach resonances without charge transfer and radiative losses. Ab initio techniques are applied to investigate electronic-ground-state properties of the (CaCr)${}^{+}$, (SrCr)${}^{+}$, (BaCr)${}^{+}$, and (YbCr)${}^{+}$ molecular ions. The potential energy curves, permanent electric dipole moments, and static electric dipole polarizabilities are computed. The spin-restricted open-shell coupled-cluster method restricted to single, double, and noniterative triple excitations and the multireference configuration-interaction method restricted to single and double excitations are employed. The scalar relativistic effects are included within the small-core energy-consistent pseudopotentials. The leading long-range induction and dispersion interaction coefficients are also reported. Finally, magnetic Feshbach resonances between the ${\mathrm{Ca}}^{+}, {\mathrm{Sr}}^{+}, {\mathrm{Ba}}^{+}$, and ${\mathrm{Yb}}^{+}$ ions interacting with the Cr atoms are analyzed. The present proposal opens the way towards robust quantum simulations and computations with ultracold ion-atom systems free of radiative charge-transfer losses.

DOI
10.1103/physreva.92.062701

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