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arXiv · 1010.3639

The three-dimensional, three state Potts model in a negative external field

Claudio Bonati·Massimo D'Elia
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Abstract

We investigate the critical behaviour of the three-dimensional, three state Potts model in presence of a negative external field h, i.e. disfavouring one of the three states. A genuine phase transition is present for all values of |h|, corresponding to the spontaneous breaking of a residual Z_2 symmetry. The transition is first/second order respectively for small/large values of |h|, with a tricritical field h_tric separating the two regimes. We provide, using different and consistent approaches, a precise determination of h_tric; we also compare with previous studies and discuss the relevance of our investigation to analogous studies of the QCD phase diagram in presence of an imaginary chemical potential.

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Claudio Bonati, Massimo D'Elia. 2010-12-30. The three-dimensional, three state Potts model in a negative external field. https://doi.org/10.1103/physrevd.82.114515

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