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arXiv · 1403.0271

Bose-Einstein condensation on quantum graphs

Jens Bolte·Joachim Kerner
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Abstract

We present results on Bose-Einstein condensation (BEC) on general compact quantum graphs, i.e., one-dimensional systems with a (potentially) complex topology. We first investigate non-interacting many-particle systems and provide a complete classification of systems that exhibit condensation. We then consider models with interactions that consist of a singular part as well as a hardcore part. In this way we obtain generalisations of the Tonks-Girardeau gas to graphs. For this we find an absence of phase transitions which then indicates an absence of BEC.

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Jens Bolte, Joachim Kerner. 2014-03-02. Bose-Einstein condensation on quantum graphs. https://doi.org/10.1142/9789814618144_0016

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