Quarkyonic Chiral Spirals in the Nambu-Jona-Lasinio Approach

TL;DR

This paper investigates inhomogeneous phases of QCD at finite density and temperature using a (3+1)D NJL model, revealing a connection to quarkyonic matter and providing insights into the QCD phase diagram.

Contribution

It introduces a (3+1)D NJL model with tensor interactions that reproduces quarkyonic chiral spirals, linking lower-dimensional theories to QCD phase structure.

Findings

Identification of quarkyonic chiral spirals in the NJL model.

Reduction of the problem to a (1+1)D NJL2 theory for solutions.

Potential guidance for locating the QCD critical point.

Abstract

We explore the inhomogeneous QCD phases at finite density and temperature using a (3+1)-dimensional Nambu-Jona-Lasinio (NJL) model in the large Nc limit with an additional attractive tensor-tensor interaction channel. For single modulated solutions, the problem reduces to solving the gap equation of a Chiral Gross-Neveu (NJL2) theory, whose minimum solution is a periodic array of chirally twisted kinks. At zero temperature, the minimum solution reduces to the quarkyonic chiral spiral found in quarkyonic matter. The connection between the quarkyonic matter and our (3+1)-dimensional NJL model is rooted on the fact that the first reduces to (1+1)-dimensional QCD and the second to the NJL2 theory, both of which have continuous chiral symmetry and asymptotic freedom. Our findings can be useful to obtain a reliable qualitative picture of the QCD phase diagram and the location of the QCD critical point in the technically challenging region of intermediate densities and temperatures.