Universal phase diagram for vortex states of layered superconductors in strong magnetic fields

We report on a Monte Carlo study of the lowest-Landau-level limit of the Lawrence-Doniach model for a layered superconductor. We have studied order parameter correlation functions for indications of the broken translational symmetry and the off-diagonal long-range order present in the mean-field-theory vortex lattice, Our results are consistent with a single first-order phase transition between a low-temperature three-dimensional vortex solid phase, with both broken translational symmetry and off-diagonal long-range order, and a high-temperature vortex liquid phase with no broken symmetries. We construct a universal phase diagram in terms of dimensionless parameters characterizing intralayer and interlayer couplings. The universal phase boundary extracted from our simulations and the associated latent heats and magnetization jumps are compared with experiment and with numerical results obtained for related models.