Intergranular fields and Josephson critical currents in HTS ceramics

Abstract
The critical current Jc of a granular HTS is modeled by Josephson type junctions to describe the weak-link network and by effective medium theories to estimate the magnetic field at the junctions. Previous theoretical work for HHc1. Intergranular fields inconsistent with earlier suppositions on Jc(H) hysteresis are found.