Hexatic phase in thin-film superconductors

Abstract

The hexatic phase-isotropic vortex fluid phase boundaries are calculated for the thin-film superconductors high- T c YBa 2 Cu 3 O 7 and low- T c Nb, in the absence of strong pinning. It is shown that decreasing the thickness of the slab leads to the decreasing of the transition temperature. As a result of strong thermal fluctuations, the transition between hexatic phase and isotropic vortex fluid in thin-film high- T c superconductors occurs at much higher fields than in low- T c ones.