Monte Carlo simulations of vortex states in high- Tc superconductors with point defects

Abstract

The phase diagram for the vortex states of high- T c superconductors with point defects in B → ∥ c → is composed by large-scale Monte Carlo simulations of the three-dimensional anisotropic, frustrated XY model. Phase transitions between the Bragg glass, vortex glass, and vortex liquid phases are characterized by various thermodynamic quantities. The so-called vortex slush phase is found between the vortex liquid phase and the vortex glass phase. Although both the vortex slush phase and the vortex liquid phase do not exhibit superconductivity, the density of dislocations changes discontinuously at the phase boundary between these two phases.