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arXiv · 1102.1860

Finite-size effects on the phase diagram of difermion condensates in two-dimensional four-fermion interaction models

L. M. Abreu·A. P. C. Malbouisson·J. M. C. Malbouisson
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Abstract

We investigate finite-size effects on the phase structure of chiral and difermion condensates at finite temperature and density in the framework of the two-dimensional large-$N$ Nambu-Jona-Lasinio model. We take into account size-dependent effects by making use of $zeta$-function and compactification methods. The thermodynamic potential and the gap equations for the chiral and difermion condensed phases are then derived in the mean-field approximation. Size-dependent critical lines separating the different phases are obtained considering anti-periodic boundary conditions for the spatial coordinate.

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L. M. Abreu, A. P. C. Malbouisson, J. M. C. Malbouisson. 2011-02-09. Finite-size effects on the phase diagram of difermion condensates in two-dimensional four-fermion interaction models. https://doi.org/10.1103/physrevd.83.025001

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