Anisotropic flux pinning in YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// single crystals

• Published in: IEEE transactions on applied superconductivity Vol. 5; no. 2; pp. 1892 - 1895
• Main Authors: Pan, V.M., Solovjov, V.F., Svetchnikov, V.L., Freyhardt, H.C.
• Format: Journal Article
• Language: English
• Published: IEEE 01-06-1995
• Subjects: Anisotropic magnetoresistance; Critical current; Crystallization; Crystals; Flux pinning; Lattices; Magnetic field measurement; Physics; Temperature dependence; Yttrium barium copper oxide
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/77.402951

Direct transport measurements of the critical currents as well as their angular and field dependencies in YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// single crystals were performed. The role of twin planes as extended defects, which provide a vortex locking, is studied and their contribution to the J/sub c/ anisotropy is analyzed. The angular dependence of the critical current is represented as a combination of a contribution from extended defects and a point-like-defect-induced anisotropic background. The latter is responsible for the major part of the measured J/sub c/ anisotropy. The observed Kramer-like scaling law concerning the dependencies of the volume pinning force versus the applied magnetic field component along the c-axis indicates a three-dimensional flux line lattice behavior and excludes vortex decoupling as a possible mechanism of the "fishtail-effect".< >