Josephson phenomenology and microstructure of YBaCuO artificial grain boundaries characterized by misalignment of the c-axes
Abstract
YBa 2Cu 3O 7- δ (YBCO) grain boundaries characterized by a misalignment of the c-axes (45° c-axis tilt or 45° c-axis twist) have been obtained by employing a recently implemented biepitaxial technique. Junctions based on these grain boundaries exhibit good Josephson properties useful for applications. High values of the ICRN product and a Fraunhofer-like dependence of the critical current on the magnetic field, differently from traditional biepitaxial junctions, have been obtained. The correlation between transport properties and microstructure has been investigated by Transmission Electron Microscopy (TEM), which was also performed on previously measured junctions. The presence of atomically clean basal plane (BP) faced tilt boundaries, among other types of interfaces, has been shown. The possibility of selecting these kinds of boundaries by controlling film growth, and their possible advantages in terms of reproducibility and uniformity of the junction properties are discussed. The possibility of employing these junctions to explore the symmetry of the order parameter is also discussed.
- Publication:
-
Physica C Superconductivity
- Pub Date:
- November 1999
- DOI:
- 10.1016/S0921-4534(99)00372-X
- Bibcode:
- 1999PhyC..326...63T