Simulation of the d.c. critical current in superconducting sintered ceramics

R. Riedinger , P. Habig , El-Kebir Hlil , M. Arnaud , C. Boulesteix

The new superconducting high-Tc sintered ceramics can be described in some case as a lattice of interconnected rods, in other cases as a more or less random packing of parallelepiped crystallites ; their size is about a few microns. The d.c. critical current at zero voltage of such a material is not related to the critical current of the bulk material, but to its granular structure. Indeed, the critical current between two adjacent cells is governed by the critical current of the weak link between them ; this link behaves within some limits as a Josephson junction, the critical current of which is known. For our present problem, the system can be modeled as a lattice of Josephson junctions. We present here results for the d.c. critical current at zero voltage of lattices of identical Josephson junctions in two dimensions. The influence of the finiteness of size of the sample is examined. The relationship with normal conductivity simulations and percolation is discussed.

Mots clés: ceramics; critical currents; high temperature superconductors; Josephson effect; critical current; sintered ceramics; parallelepiped crystallites; granular structure; weak link; Josephson junction; conductivity; percolation

Domaines: Articles anciens

R. Riedinger, P. Habig, El-Kebir Hlil, M. Arnaud, C. Boulesteix. Simulation of the d.c. critical current in superconducting sintered ceramics. Revue de Physique Appliquée, 1990, 25 (1), pp.67-72. ⟨10.1051/rphysap:0199000250106700⟩. ⟨jpa-00246164⟩