Microstructure design by twinning in high-temperature superconductor YBa2Cu3O7−δ for enhanced Jc at high magnetic fields

The principles of microstructure design by twinning in YBa2Cu3O7−δ (YBCO) crystals for enhanced Jc at high magnetic fields are developed. The resources of twin microstructure design in YBCO by twining are analyzed by comparing pinning capability of different microstructures: system of plane-parallel twin lamellas; system of wedge-shaped twins; microstructure composed of twin intersections. Rough estimations of relative pinning strength of the basic crystal defect for each specific type of twin microstructure were done.