Correlation between effects of electric current and magnetic field on transport properties of electron-doped manganite La_0.7Ce_0.3MnO₃ thin films

Abstract

We report the effect of electric current and magnetic field, separately and in conjugation, on the transport behaviour of patterned La_0.7Ce_0.3MnO₃ thin films. In the absence of a magnetic field, a significant reduction in peak resistance (R_p) was found with increasing bias current. This effect is also present when a magnetic field is applied, though the magnitude of the electroresistance (ER = [R(I = 0.05 µA)−R(I = 50 µA)]/R(I = 50 µA)) decreases. The metal–insulator transition temperature (T_p) increases both with increasing current and with magnetic field. We observe an interesting correlation between electric current and magnetic field: the magnetoresistance (MR = [R_H = 0−R_H = 1 T]/R_H = 0) decreases with increasing bias current, while ER decreases with increasing magnetic field. Both ER and MR show a maximum near T_p. The interesting correlation between these two effects suggests that both these effects arise from the same origin.