A New Process with the Promise of High J_c in Oxide Superconductors

TLDR

The authors report a new process that promises high critical current density in oxide superconductors. The process consists of three stages: rapid heating and quenching from the Y₂O₃ plus liquid region, reheating to the Y₂BaCuO₅ plus liquid region, and slow cooling with a temperature gradient in flowing oxygen to grow a unidirectionally textured YBa₂Cu₃Oₓ phase. The process produces well‑textured YBa₂Cu₃Oₓ with high Jc in magnetic fields and shows Bean’s critical state.

Abstract

We report a new process which promises high critical current density in oxide superconductors. The process consists of three stages. Firstly a YBa 2 Cu 3 O x sample is rapidly heated and quenched from the Y 2 O 3 plus liquid region. Subsequently the quenched sample is reheated to the Y 2 BaCuO 5 plus liquid region, and then slowly cooled with a temperature gradient in flowing oxygen. The process enables us to grow a superconducting phase unidirectionally and to suppress the second phase intrusion, leading to the production of well textured YBa 2 Cu 3 O x which yields a high J c value in the presence of magnetic fields. It is also found that Bean's critical state is realized in such high J c samples.