A non-perturbative method of Field Correlators is applied to calculate the Polyakov loop dependence on temperature, L(T), in the 2+1 flavor QCD with small quark masses, so the only relevant scale is the color-electric string tension σ(T). Polyakov loop in the temperature range 100 MeV ≲T≲ 400 MeV is expressed via the heavy-light meson mass that decreases with T as σ(T). The latter is deduced from a gradually vanishing chiral condensate. The resulting L(T) is in good agreement with recent lattice data.
@article{arxiv.1812.01998,
title = {Dynamics of the Polyakov loops in QCD},
author = {R. A Abramchuk and Z. V. Khaidukov and Yu. A. Simonov},
journal= {arXiv preprint arXiv:1812.01998},
year = {2019}
}