Flux creep associated with bulk pinning and edge barriers in BSCCO-2212 single crystals

Abstract

We have examined the flux creep behaviour in high-quality BSCCO-2212 single crystals by dynamic relaxation of the global magnetization using a vibrating-sample magnetometer. The irreversible magnetization is attributed to bulk pinning at low temperatures and to edge barriers at high temperatures. The increase of current at the anomalous `arrowhead' feature is related to the penetration of a Bean-type profile through the sample at a field . We show that at flux creep is enhanced. The fast-creep regime survives over a narrow field range up to a field , associated with the irreversibility line of the bulk pinning. Apart from the temperatures and fields where the arrowhead is observed, the creep rate has a similar normalized field dependence at all temperatures.