Francesca Cuteri

Flux tubes in the SU(3) vacuum: London penetration depth and coherence length

Within the dual superconductor scenario for the QCD confining vacuum, the chromoelectric field generated by a static

Flux tubes at finite temperature

q\overline{q}

Roberge-Weiss transition inNf=2QCD with Wilson fermions andNτ=6

pair can be fitted by a function derived, by dual analogy, from a simple variational model for the magnitude of the normalized order parameter of an isolated Abrikosov vortex. Previous results for the SU(3) vacuum are revisited, but here the transverse chromoelectric field is measured by means of the connected correlator of two Polyakov loops and, in order to reduce noise, the smearing procedure is used instead of cooling. The penetration and coherence lengths of the flux tube are then extracted from the fit and compared with previous results.

Flux tubes in the QCD vacuum

A bstractThe 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, if the distance between the static sources is kept fixed at about 0.76fm≃1.6/σ

QCD flux tubes across the deconfinement phase transition

0.76\ \mathrm{fm}\simeq 1.6/\sqrt{\sigma }

Anatomy of SU(3) flux tubes at finite temperature

and the temperature is increased towards and above the deconfinement temperature Tc, 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 Tc 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.

Flux tubes and coherence length in the SU(3) vacuum

QCD with imaginary chemical potential is free of the sign problem and exhibits a rich phase structure constraining the phase diagram at real chemical potential. We simulate the critical endpoint of the Roberge-Weiss (RW) transition at imaginary chemical potential for

Flux tubes in QCD with (2+1) HISQ fermions

N_\text{f}=2