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Ground state properties of a dilute homogeneous Bose gas of hard disks in two dimensions

F. Mazzanti·A. Polls·A. Fabrocini
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Abstract

The energy and structure of a dilute hard-disks Bose gas are studied in the framework of a variational many-body approach based on a Jastrow correlated ground state wave function. The asymptotic behaviors of the radial distribution function and the one-body density matrix are analyzed after solving the Euler equation obtained by a free minimization of the hypernetted chain energy functional. Our results show important deviations from those of the available low density expansions, already at gas parameter values $x\sim 0.001$. The condensate fraction in 2D is also computed and found generally lower than the 3D one at the same $x$.

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F. Mazzanti, A. Polls, A. Fabrocini. 2004-10-27. Ground state properties of a dilute homogeneous Bose gas of hard disks in two dimensions. https://doi.org/10.1103/physreva.71.033615

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