Study of dipole moments of LiSr and KRb molecules by quantum Monte Carlo methods

Abstract

Heteronuclear dimers are of significant interest to experiments seeking to exploit ultracold polar molecules in a number of novel ways including precision measurement, quantum computing, and quantum simulation. We calculate highly accurate Born-Oppenheimer total energies and electric dipole moments as a function of internuclear separation for two such dimers, LiSr and KRb. We apply fully-correlated, high-accuracy quantum Monte Carlo methods for evaluating these molecular properties in a many-body framework. We use small-core effective potentials combined with multi-reference Slater-Jastrow trial wave functions to provide accurate nodes for the fixed-node diffusion Monte Carlo method. For reference and comparison, we calculate the same properties with Hartree-Fock and with restricted Configuration Interaction methods, and carefully assess the impact of the recovered many-body correlations on the calculated quantities. For LiSr we find a highly nonlinear dipole moment curve, which may make this molecule's dipole moment tunable through vibrational state control.

13 pages, 6 figures, 2 tables, 78 references. Submitted to a special issue of Molecular Physics on "Manipulation of Molecules with Electromagnetic Fields." Published June 2013. http://dx.doi.org/10.1080/00268976.2013.788741

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Cited by in corpus (5)

• Manipulation of Molecules with Electromagnetic Fields
• Strongly interacting ultracold polar molecules
• Diatomic molecules of alkali-metal and alkaline-earth-metal atoms: interaction potentials, dipole moments, and polarizabilities
• Double Degenerate Bose-Fermi Mixture of Strontium and Lithium
• Fractional charge by fixed-node diffusion Monte Carlo