Anisotropic energy dissipation in high-Tcceramic superconductors: Local-field effects

Abstract

In a recent communication Ji, Rzchowski, and Tinkham have interpreted the history dependence of the microwave surface resistance in polycrystalline ${\mathrm{YBa}}_2$ ${\mathrm{Cu}}_3$ ${\mathrm{O}}_{7\mathrm{-}\mathrm{\delta }}$ in terms of granularity and flux flow. In this paper we show that the proposed model can be extended to understand the hysteretic dissipation, found in polycrystalline superconductors through I-V dc curves, for the case where the magnetic field lies parallel and antiparallel to the transport current.