Flux tubes at finite temperature

TL;DR

This study uses lattice simulations to explore how chromoelectric flux tubes in SU(3) gauge theory behave across the deconfinement transition, revealing a shrinking amplitude but stable shape above the critical temperature.

Contribution

It provides new insights into the behavior of flux tubes at finite temperature, especially their evaporation above the deconfinement point, contrasting with superconductivity models.

Findings

Flux tube amplitude decreases above T_c

Flux tube shape remains stable across deconfinement

Evidence of flux-tube structures in the deconfined phase

Abstract

The chromoelectric field generated by a static quark-antiquark pair, with its peculiar tube-like shape, can be nicely described, at zero temperature, within the dual superconductor scenario for the QCD confining vacuum. In this work we investigate, by lattice Monte Carlo simulations of the SU(3) pure gauge theory, the fate of chromoelectric flux tubes across the deconfinement transition. We find that, as the temperature is increased towards and above the deconfinement temperature $T_c$, the amplitude of the field inside the flux tube gets smaller, while the shape of the flux tube does not vary appreciably across deconfinement. This scenario with flux-tube "evaporation" above $T_c$ has no correspondence in ordinary (type-II) superconductivity, where instead the transition to the phase with normal conductivity is characterized by a divergent fattening of flux tubes as the transition temperature is approached from below. We present also some evidence about the existence of flux-tube structures in the magnetic sector of the theory in the deconfined phase.