Variational Approach to the Dilute Bose Gas

M. Bijlsma; H. T. C. Stoof

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arXiv · cond-mat/9507134

Variational Approach to the Dilute Bose Gas

M. Bijlsma·H. T. C. Stoof

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Abstract

We study the weakly-interacting Bose gas in both two and three dimensions using a variational approach. In particular we construct the thermodynamic potential of the gas to within ladder approximation and find by minimization an accurate mean-field description of the dilute Bose gas. Using spin-polarized atomic hydrogen as a specific example, we obtain an improved description of the Bose-Einstein condensed phase in three dimensions and a signature of a phase transition in two dimensions. The latter cannot be found by straightforward application of perturbation theory around the ideal Bose gas.

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M. Bijlsma, H. T. C. Stoof. 1995-07-31. Variational Approach to the Dilute Bose Gas. https://arxiv.org/abs/cond-mat/9507134

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