Low-field flux pinning in twinned and detwinned single crystals of YBa2Cu3O7−<i>x</i>

Abstract

Flux trapping in single crystals of YBa2Cu3O7−x before and after twin removal has been measured for vortices parallel and perpendicular to the c axis. The results show clearly that, for low applied magnetic fields, twins contribute significantly to flux pinning over the temperature range 60 to 85 K when the vortices are parallel to the twin boundaries (i.e., parallel to the c axis).