Magnetoresistance profile of a Bi2Sr2CaCu2Oδ thin film: On the behavior of the potential barrier in the flux creep process

Abstract

The magnetoresistance profile was shown to have an activation related peaked behavior which is a consequence of the Kim-Anderson flux creep theory. The corresponding energy scale or potential barrier to the activation mechanism was analyzed in terms of its dependence on temperature and applied magnetic field. The behavior was correlated with the features of the magnetoresistance profile. The potential barrier profile in temperature presents two prominent features which may be able to explain the asymmetry of the magnetoresistance peak. Also, the low temperature regime of the potential barrier which decreases with increasing temperature was pointed out to result to a more readily activated flux flow manifested as the rise in the low temperature magnetoresistance. However, the high temperature feature of the potential barrier profile is yet to be accounted for.