DC magnetic characterization and pinning analysis on Nd1.85Ce0.15CuO4 cuprate superconductor

Abstract

Abstract We report the analysis of the magnetic response detected on the cuprate superconductor Nd1.85Ce0.15CuO4. In particular the magnetic behavior of the sample has been studied by means of DC magnetization measurements as a function of the temperature (T) and DC magnetic field (H). The superconducting critical temperature Tc has been obtained by analyzing the m(T) curve performed in Zero Field Cooling-Field Cooling conditions. Moreover, the m(T) curve shows the presence of a magnetic background for temperatures above Tc. By considering the superconducting m(H) hysteresis loop at different temperatures, it can be noted that the width of the curves appears narrow corresponding to a weak superconductivity. This is confirmed by the field dependence of the critical current densities Jc extracted from the superconducting hysteresis loops m(H) at different temperatures within the Bean critical state model. In fact, at the lowest measurement temperature, Jc is close to zero already at low magnetic fields. Nevertheless, by means of the temperature dependence of Jc, the sample shows a strong pinning behavior that can open perspectives for future improvement in the fabrication of this material.