Inhomogeneous current distribution in wide high-temperature superconducting small-angle grain boundaries
Institut für Materialphysik, University of Göttingen, Friedrich-Hund-Platz 1, 37077
Corresponding author: a email@example.com
Published online: 14 December 2004
Using space resolved magneto-optical microscopy we have studied the development of the critical state in high temperature superconducting small-angle grain boundaries in magnetisation experiments. It has been found that with respect to the position in the grain boundary plane this critical state develops in a highly inhomogeneous manner. Towards the centre of the grain boundary there exists a distinct suppression of the inter-granular currents flowing across the grain boundary. A strong correlation between the static (critical current) and the dynamical properties (e.g. electric field or flux-line velocity) of the vortex system inside the grain boundary appears to be the principal mechanism for the observed inhomogeneous current distribution in wide bi-crystalline current bridges.
PACS: 74.25.Sv – Critical currents / 74.72.Bk – Y-based cuprates / 74.78.Bz – High-Tc films / 74.81.Bd – Granular, melt-textured, amorphous and composite superconductors
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2004