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arXiv · 0812.3844

Two-dimensional weakly interacting Bose gas: equation of state

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

The equation of state of a weakly interacting two-dimensional Bose gas is studied at zero temperature by means of quantum Monte Carlo methods. Going down to as low densities as na^2 ~ 10^{-100} permits us for the first time to obtain agreement on beyond mean-field level between predictions of perturbative methods and direct many-body numerical simulation, thus providing an answer to the fundamental question of the equation of state of a two-dimensional dilute Bose gas in the universal regime (i.e. entirely described by the gas parameter na^2). We also show that the measure of the frequency of a breathing collective oscillation in a trap at very low densities can be used to test the universal equation of state of a two-dimensional Bose gas.

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G. E. Astrakharchik, J. Boronat, J. Casulleras, I. L. Kurbakov, Yu. E. Lozovik. 2009-05-14. Two-dimensional weakly interacting Bose gas: equation of state. https://arxiv.org/abs/0812.3844

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