Polyakov loop effects on the phase diagram in strong-coupling lattice QCD
Abstract
We investigate the Polyakov loop effects on the QCD phase diagram by using the strong-coupling (1 /g2 ) expansion of the lattice QCD (SC-LQCD) with one species of unrooted staggered quark, including O (1 /g4) effects. We take account of the effects of Polyakov loop fluctuations in Weiss mean-field approximation (MFA), and compare the results with those in the Haar-measure MFA (no fluctuation from the mean-field). The Polyakov loops strongly suppress the chiral transition temperature in the second-order/crossover region at small chemical potential (μ ), while they give a minor modification of the first-order phase boundary at larger μ . The Polyakov loops also account for a drastic increase of the interaction measure near the chiral phase transition. The chiral and Polyakov loop susceptibilities (χσ,χℓ) have their peaks close to each other in the second-order/crossover region. In particular in Weiss MFA, there is no indication of the separated deconfinement transition boundary from the chiral phase boundary at any μ . We discuss the interplay between the chiral and deconfinement dynamics via the bare quark mass dependence of susceptibilities χσ ,ℓ.
- Publication:
-
Physical Review D
- Pub Date:
- June 2017
- DOI:
- 10.1103/PhysRevD.95.114505
- arXiv:
- arXiv:1610.09288
- Bibcode:
- 2017PhRvD..95k4505M
- Keywords:
-
- High Energy Physics - Lattice
- E-Print:
- 17 pages, 17 figures