An empirical model for magnetic field dependent resistivity and magnetoresistance in manganites: application on polycrystalline charge-ordered La0.4Gd0.1Ca0.5MnO3

Abstract

In this paper, we have investigated the electrical and magnetic response of a La_0.4Gd_0.1Ca_0.5MnO₃ polycrystalline sample. This sample seems to exhibit fascinating phenomena like charge ordering, magnetic phase separation, training effects and kinetic arrest. It also shows colossal values of negative magnetoresistance (∼91.7% at 96 K under 1 T applied magnetic field), which raises the possibility of using this sample for technological applications. We have also proposed, in this work, a new empirical model to describe the evolution of resistivity and magnetoresistance as a function of magnetic field. This model was successfully tested on the La_0.4Gd_0.1Ca_0.5MnO₃ sample in spite of its complicated magnetic behavior, which suggests the use of this model for other magnetic samples in order to check its validity.