Flux tubes and topological charges in finite-temperature lattice QCD
  Topological properties of the vacuum were investigated in finite-temperature lattice QCD without and with dynamical quarks using a local operator of topological charge density and a variant of cooling. Below the deconfinement temperature evidence for flux tube formation was observed in the distribution of topological charge density around a static $Q\bar Q$ pair. With dynamical quarks, the flux tube breaks when the distance between the static quark and antiquark increases. 
M. Faber, H. Markum, S.Olejnik, W.Sakuler