Dislocation description of twins in high-temperature superconductor YBa₂Cu₃O₇₋δ

Abstract

The thin twins theory consistently applied to the dislocation description of twins in the high-temperature superconductor YBa₂Cu₃O₇₋δ(YBCO). Quantitative analysis of the twin shape shows an agreement with theoretical consideration and gives new method to evaluate the twin boundary energy γtw. Friction stress Sfr acting on a twinning dislocation is also determined. The formation of a twin and twin microstructures are analyzed. The principles of microstructure design by twinning in YBCO crystals for enhanced Jc at high magnetic fields are discussed.