Exploring the QCD phase diagram at finite density by the complex Langevin method on a $16^3\times 32$ lattice

Abstract

We explore the QCD phase diagram at finite density with four-flavor staggered fermions using the complex Langevin method, which is a promising approach to overcome the sign problem. In our previous work on an $8^3\times 16$ lattice at $\beta =5.7$ with the quark mass $m=0.01$, we have found that the baryon number density has a clear plateau as a function of the chemical potential. In this study, we use a $16^3\times 32$ lattice to reduce finite volume effects and find that the plateau structure survives. Moreover, the number of quarks in the plateau region turns out to be 24, which is exactly the same as the one obtained previously on the $8^3\times 16$ lattice. We provide a simple interpretation of this number, which suggests that the Fermi sphere is starting to form.

arXiv comment7 pages, 2 figures, submitted to the proceedings for 37th International Symposium on Lattice Field Theory - Lattice2019

References in corpus (12)

• The Complex Langevin method: When can it be trusted?
• Complex Langevin: Etiology and Diagnostics of its Main Problem
• Simulating full QCD at nonzero density using the complex Langevin equation
• Controlling complex Langevin dynamics at finite density
• The argument for justification of the complex Langevin method and the condition for correct convergence
• Adaptive stepsize and instabilities in complex Langevin dynamics
• New insights into the problem with a singular drift term in the complex Langevin method
• Complex Langevin dynamics for dynamical QCD at nonzero chemical potential: a comparison with multi-parameter reweighting
• Applying Complex Langevin Simulations to Lattice QCD at Finite Density
• Complex Langevin calculations in finite density QCD at large $\mu /T$ with the deformation technique
• Applying Complex Langevin to Lattice QCD at finite $\mu$
• Exploring the phase diagram of finite density QCD at low temperature by the complex Langevin method