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The (2+1)-dimensional Gross-Neveu model with a U(1) chiral symmetry at non-zero temperature

S. J. Hands·J. B. Kogut·C. G. Strouthos
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Abstract

We present results from numerical simulations of the (2+1)-dimensional Gross-Neveu model with a U(1) chiral symmetry and N_f=4 fermion species at non-zero temperature. We provide evidence that there are two different chirally symmetric phases, one critical and one with finite correlation length, separated by a Berezinskii-Kosterlitz-Thouless transition. We have also identified a regime above the critical temperature in which the fermions acquire a screening mass even in the absence of chiral symmetry breaking, analogous to the pseudogap behaviour observed in cuprate superconductors.

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S. J. Hands, J. B. Kogut, C. G. Strouthos. 2001-07-02. The (2+1)-dimensional Gross-Neveu model with a U(1) chiral symmetry at non-zero temperature. https://doi.org/10.1016/s0370-2693(01)00885-1

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