Estimate of Attainable Critical Current Density in Superconducting YBa₂Cu₃O_7-δ

Abstract

Attainable critical current density in oxide superconductor YBa 2 Cu 3 O 7-δ is estimated by an ordinary analyzing method in flux pinning phenomena with superconducting parameters obtained from a magnetization measurement. The pinning mechanisms considered here are an anisotropy in the upper critical field and an electron scattering effect for grain boundaries and twinning planes. While the elementary pinning force of these planar defects is small due to a small thermodynamic critical field at 77 K, a critical current density comparable to that of Nb-Ti at 4.2 K is expected to be attained by increasing the pin concentration.