Modification of the Kosterlitz–Thouless transition to the temperature dependent resistance for anisotropic superconductors

Abstract It is found that the temperature dependence of the resistance transition can be analyzed by the modified Coulomb–Gas scaling law for anisotropic superconductors [Y.Z. Zhang, R. Deltour, Z.X. Zhao, Phys. Rev. Lett. 85 (2000) 3492]. In this Letter, through introducing the thermal activation energy and the pinning energy in the correlation length, the modified Coulomb–Gas scaling law is deduced from the phenomenological Kosterlitz–Thouless transition theory. This modified Kosterlitz–Thouless model is applied to the re-analysis of the temperature dependence of the resistance transition of an oxygen-deficient YBa 2 Cu 3 O x crystal reported in literature. Through this model, the mean height of pinning U 0 can be directly calculated from the resistance transition. It is found the mean height of pinning can be described as U 0 ( T , H ) ∝ ( 1 − T / T c ) H − β , where T c is the mean field critical temperature, and β = 1.08 . These experimental results are consistent with the proposed model.