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Weakly interacting two-dimensional system of dipoles: limitations of mean-field theory

G. E. Astrakharchik·J. Boronat·J. Casulleras·I. L. Kurbakov·Yu. E. Lozovik
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Abstract

We consider a homogeneous 2D Bose gas with repulsive dipole-dipole interactions. The ground-state equation of state, calculated using the Diffusion Monte Carlo method, shows quantitative differences with predictions of commonly used Gross-Pitaevskii mean-field theory. The static structure factor, pair distribution function and condensate fraction are calculated in a wide range of the gas parameter. Differences with mean-field theory are reflected in the frequency of the lowest ``breathing'' mode for harmonically trapped systems.

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G. E. Astrakharchik, J. Boronat, J. Casulleras, I. L. Kurbakov, Yu. E. Lozovik. 2006-12-29. Weakly interacting two-dimensional system of dipoles: limitations of mean-field theory. https://doi.org/10.1103/physreva.75.063630

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