Two-dimensional weakly interacting Bose gas: equation of state
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.
Cite
@article{arxiv.0812.3844,
title = {Two-dimensional weakly interacting Bose gas: equation of state},
author = {G. E. Astrakharchik and J. Boronat and J. Casulleras and I. L. Kurbakov and Yu. E. Lozovik},
journal= {arXiv preprint arXiv:0812.3844},
year = {2009}
}
Comments
New data points added at smaller densities. Correspondingly Table I, Figs. 1 and 2 are updated. Results by L. Pricoupenko (Ref [15]) are given in Table II. Comment [25] by Y. Castin is added. Minor changes in response to referee comments