INTRINSIC CRITICAL-CURRENT FOR A 3D JOSEPHSON-JUNCTION MODEL WITH BONDING DISORDER AND FRUSTRATION

We modeled ceramic high T-c (HTS) materials as quantum-capacitive Jose phson junction arrays (JJA), with weakly coupled superconducting grain s on a 3D lattice, and Angstrom scale parameters. We studied a highly anisotropic 3D-XY/JJA model with bonding disorder (defect and probabil ity) and frustration (vector potential) by the use of Monte Carlo simu lation. We also obtained a phase-boundary diagram of magnetic field H- temperature T-anisotropy alpha. The ''glass like behavior'' of the 3D- XY/JJA model seems to be at least qualitatively consistent with variou s experimental data discovered so far. (C) 1997 Elsevier Science B.V.