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arXiv · 0902.4119

Multiple condensed phases in attractively interacting Bose systems

M. Männel·K. Morawetz·P. Lipavský
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Abstract

We investigate a Bose gas with finite-range interaction using a scheme to eliminate unphysical processes in the T-matrix approximation. In this way the corrected T-matrix becomes suitable to calculate properties below the critical temperature. For attractive interaction, an Evans-Rashid transition occurs between a quasi-ideal Bose gas and a BCS-like phase with a gaped dispersion. The gap decreases with increasing density and vanishes at a critical density where the single-particle dispersion becomes linear for small momenta indicating Bose-Einstein condensation. The investigation of the pressure shows however, that the mentioned quantum phase transitions might be inaccessible due to a preceding first order transition.

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M. Männel, K. Morawetz, P. Lipavský. 2009-10-13. Multiple condensed phases in attractively interacting Bose systems. https://doi.org/10.1088/1367-2630%2F12%2F3%2F033013

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