Deviations from plastic barriers in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ thin films

TL;DR

This study investigates deviations from expected plastic barrier behavior in resistive transitions of Bi$_2$Sr$_2$CaCu$_2$O$_{8+eta}$ thin films under magnetic fields, proposing an empirical model that aligns with experimental data.

Contribution

The paper introduces an empirical barrier form that accurately characterizes deviations from plastic barriers in high-temperature superconductor thin films.

Findings

Empirical barrier form matches experimental resistive transition data.

Deviations from plastic barriers are explained by the empirical model.

Plastic barrier predictions are valid within a limited magnetic field range.

Abstract

Resistive transitions of an epitaxial Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ thin film were measured in various magnetic fields ($H\parallel c$), ranging from 0 to 22.0 T. Rounded curvatures of low resistivity tails are observed in Arrhenius plot and considered to relate to deviations from plastic barriers. In order to characterize these deviations, an empirical barrier form is developed, which is found to be in good agreement with experimental data and coincide with the plastic barrier form in a limited magnetic field range. Using the plastic barrier predictions and the empirical barrier form, we successfully explain the observed deviations.