c -axis correlated pinning behavior near the irreversibility fields

Abstract

The authors found that the peak at the parallel external field (B‖c) to the c axis in the angular dependence of Jc shrinks and almost disappears with increasing a magnetic field but it grows again with further increasing of a magnetic field at various temperatures for high-Jc Sm1+xBa2−xCu3Oy films. These behaviors can be explained by the flux pinning properties of the interstitial vortices, which locate in between the vortices pinned by the c-axis correlated disorders. From the obtained experimental results, the collective correlated pinned glass state is proposed in a high field region in the vortex glass states.