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arXiv · 2002.01624

The condensed fraction of a homogeneous dilute Bose gas within the improved Hartree-Fock approximation

Nguyen Van Thu·Jonas Berx
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Abstract

Motivated by the recent experiment [R. Lopes et. al., Phys. Rev. Lett. 119, 190404 (2017)] with a homogeneous Bose gas, we investigate a homogeneous dilute Bose gas to calculate the quantum depletion density. By means of the Cornwall-Jackiw-Tomboulis effective action approach within an improved Hartree-Fock approximation, the condensed fraction is recovered in a simpler manner and compared with corresponding findings in experimental data. Additionally, higher-order terms are taken into account for several physical quantities, in particular for the chemical potential and free energy density.

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Nguyen Van Thu, Jonas Berx. 2020-02-05. The condensed fraction of a homogeneous dilute Bose gas within the improved Hartree-Fock approximation. https://doi.org/10.1007/s10955-022-02944-0

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