Ground state energy density of a dilute Bose gas in the canonical transformation

Sang-Hoon Kim; Chul Koo Kim; Mukunda P. Das

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Ground state energy density of a dilute Bose gas in the canonical transformation

Sang-Hoon Kim·Chul Koo Kim·Mukunda P. Das

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Abstract

A ground state energy density of an interacting dilute Bose gas system is studied in the canonical transformation scheme. It is shown that the transformation scheme enables us to calculate a higher order correction of order $n a^3$ in the particle depletion and ground state energy density of a dilute Bose gas system, which corresponds to the density fluctuation contribution from the excited states. The coefficient of $n a^3$ term is shown to be $2(π- 8/3)$ for the particle depletion, and $16(π- 8/3)$ for the ground state energy density.

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Sang-Hoon Kim, Chul Koo Kim, Mukunda P. Das. 2007-08-01. Ground state energy density of a dilute Bose gas in the canonical transformation. https://arxiv.org/abs/cond-mat/0603479

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