In Search of the Vortex Loop Blowout Transition for a type-II   Superconductor in a Finite Magnetic Field
  The 3D uniformly frustrated XY model is simulated to search for a predicted "vortex loop blowout" transition within the vortex line liquid phase of a strongly type-II superconductor in an applied magnetic field. Results are shown to strongly depend on the precise scheme used to trace out vortex line paths. While we find evidence for a transverse vortex path percolation transition, no signal of this transition is found in the specific heat. 
P. Olsson and S. Teitel