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arXiv · 0804.0364

Second order quantum phase transition of a homogeneous Bose gas with attractive interactions

P. Ziń·B. Oleś·M. Trippenbach·K. Sacha
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Abstract

We consider a homogeneous Bose gas of particles with an attractive interaction. Mean field theory predicts for this system a spontaneous symmetry breaking at a certain value of the interaction strength. We show that at this point a second-order quantum phase transition occurs. We investigate the system in the vicinity of the critical point using Bogoliubov theory and a continuous description, that allows us to analyze {\it quantum fluctuations} in the system even when the Bogoliubov approach breaks down.

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P. Ziń, B. Oleś, M. Trippenbach, K. Sacha. 2008-04-02. Second order quantum phase transition of a homogeneous Bose gas with attractive interactions. https://doi.org/10.1103/physreva.78.023620

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