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Energy and Structure of Hard-Sphere Bose Gases in three and two dimensions

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

The energy and structure of dilute gases of hard spheres in three dimensions is discussed, together with some aspects of the corresponding 2D systems. A variational approach in the framework of the Hypernetted Chain Equations (HNC) is used starting from a Jastrow wavefunction that is optimized to produce the best two--body correlation factor with the appropriate long range. Relevant quantities describing static properties of the system are studied as a function of the gas parameter $x=ρa^d$ where $ρ$, $a$ and $d$ are the density, $s$--wave scattering length of the potential and dimensionality of the space, respectively. The occurrence of a maximum in the radial distribution function and in the momentum distribution is a natural effect of the correlations when $x$ increases. Some aspects of the asymptotic behavior of the functions characterizing the structure of the systems are also investigated.

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F. Mazzanti, A. Polls, A. Fabrocini. 2004-10-26. Energy and Structure of Hard-Sphere Bose Gases in three and two dimensions. https://doi.org/10.1007/s10909-005-2295-y

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