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arXiv · 0903.1868

Inhomogeneous Condensates in the Thermodynamics of the Chiral NJL_2 model

Gokce Basar·Gerald V. Dunne·Michael Thies
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Abstract

We analyze the thermodynamical properties, at finite density and nonzero temperature, of the (1+1)-dimensional chiral Gross-Neveu model (the NJL_2 model), using the exact inhomogeneous (crystalline) condensate solutions to the gap equation. The continuous chiral symmetry of the model plays a crucial role, and the thermodynamics leads to a broken phase with a periodic spiral condensate, the "chiral spiral", as a thermodynamically preferred limit of the more general "twisted kink crystal" solution of the gap equation. This situation should be contrasted with the Gross-Neveu model, which has a discrete chiral symmetry, and for which the phase diagram has a crystalline phase with a periodic kink crystal. We use a combination of analytic, numerical and Ginzburg-Landau techniques to study various parts of the phase diagram.

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Gokce Basar, Gerald V. Dunne, Michael Thies. 2009-03-10. Inhomogeneous Condensates in the Thermodynamics of the Chiral NJL_2 model. https://doi.org/10.1103/physrevd.79.105012

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