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arXiv:1506.03752 · Physical Review B

Coordinated wave function for the ground state of liquid He4

Y. Lutsyshyn

Published Dec 14, 2015• 3 citations
arXivHTMLPDF

Abstract

We present a variational ansatz for the ground state of a strongly correlated Bose system. This ansatz goes beyond the Jastrow-Feenberg functional form and explicitly enforces coordination shells in the structure of the wave function. We apply this ansatz to liquid helium-4 with a simple three-variable parametrization of the pair functions. The optimized wave function is found to give an excellent description of the mid-range correlations in the fluid. We also demonstrate the possibility to use this ansatz to study inhomogeneous systems. The phase separation and free surface emerge naturally in this wave function, even though it is constructed of short-range two-body functions and does not contain one-body terms. Because no explicit description of the surface is necessary, this provides a powerful description tool for cluster states.

DOI
10.1103/physrevb.92.214507

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