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arXiv · 0801.1387

Stability of the homogeneous Bose-Einstein condensate at large gas parameter

Abdulla Rakhimov·Chul Koo Kim·Sang-Hoon Kim·Jae Hyung Yee
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Abstract

The properties of the uniform Bose gas is studied within the optimized variational perturbation theory (Gaussian approximation) in a self-consistent way. It is shown that the atomic BEC with a repulsive interaction becomes unstable when the gas parameter gamma=rho a^3 exceeds a critical value gamma_{crit} ~ 0.01. The quantum corrections beyond the Bogoliubov-Popov approximation to the energy density, chemical potential and pressure in powers of gamma expansions are presented.

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Abdulla Rakhimov, Chul Koo Kim, Sang-Hoon Kim, Jae Hyung Yee. 2008-01-09. Stability of the homogeneous Bose-Einstein condensate at large gas parameter. https://doi.org/10.1103/physreva.77.033626

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