Effect of nonzero temperature to condensed fraction of a homogeneous dilute weakly interacting Bose gas

Nguyen Van Thu; Pham Duy Thanh

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arXiv · 2312.08379

Effect of nonzero temperature to condensed fraction of a homogeneous dilute weakly interacting Bose gas

Nguyen Van Thu·Pham Duy Thanh

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Abstract

We investigate the effect of non-zero temperature to the condensate fraction of a homogeneous dilute weakly interacting Bose gas in very low-temperature region. Within inproved Hartree-Fock approximation, the Cornwall-Jackiw-Tomboulis effective action approach shows that the thermal fluctuations make the condensate fraction decrease as a second and fourth-order power law of temperature. The result is compared with experimental data. Indeed, the effect of non-infinite size of the trap is also integrated.

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Nguyen Van Thu, Pham Duy Thanh. 2023-12-10. Effect of nonzero temperature to condensed fraction of a homogeneous dilute weakly interacting Bose gas. https://arxiv.org/abs/2312.08379

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