Magnetization Relaxation and Resistive Behaviour of High-Tc Superconductors

Abstract

From the analysis of magnetization relaxation data on various types of samples and MonteCarlo calcu1ations Hagen and Griessen concluded that the existing ex~erimental data can be understood in terms of a model which incorporates a distribution m(V ) of activation energies for thermally activated flux motion. This model is extended to include f1ux-flow in order to reproduce the characteristic features of current-voltage curves of high-Tc superconductors. In particular the re cent data of Koch et al. and Zeldov et al. can be explained without invoking a continuous phase transition (freezing into a superconducting vortex-glass phase) or a logarithmic current dependence of the activation energy.