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arXiv · 2112.02261

Inhomogeneous Phases in the Chiral Gross-Neveu Model on the Lattice

Keita Horie·Chiho Nonaka
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Abstract

We discuss possible existence of inhomogeneous phase in low temperature and high density region in the 1+1 dimensional chiral Gross-Neveu ( $\chi$GN$_2$ ) model on the lattice. First we investigate the phase structure of the $\chi$GN$_2$ model at vanishing chemical potential, changing temperature. From behavior of $\Delta^2 = \Sigma^2 + \Pi^2$ as a function of Monte Carlo time, a candidate of an order parameter for chiral symmetry in the $\chi$GN$_2$ model is $\Delta$. At vanishing chemical potential, we observe restoration of chiral symmetry at high $T$. In low temperature and high chemical potential region, we find existence of inhomogeneous phase in spatial correlation functions of $\sigma$ and $\pi$. The signal of inhomogeneous phase in correlation function of $\Delta$ is more clearly than that of $\sigma$ or $\pi$.

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Keita Horie, Chiho Nonaka. 2021-12-04. Inhomogeneous Phases in the Chiral Gross-Neveu Model on the Lattice. https://arxiv.org/abs/2112.02261

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