Thermal fluctuation correction to magnetization and specific heat of vortex solids in type-II superconductors

Abstract

A systematic calculation of magnetization and specific beat contributions due to fluctuations of vortex lattice in strongly type-II superconductors to precision of 1% is presented. We complete the calculation of the two loop low temperature perturbation theory by including the umklapp processes. Then the Gaussian variational method is adapted to calculation of thermodynamic characteristics of the two-dimensional and the three-dimensional vortex solids in high magnetic field. Based on it as a starting point for a perturbation theory we calculate the leading correction providing simultaneously an estimate of precision. The results are compared to existing nonperturbative approaches.