Intrinsic electroresistance of Sm0.60Sr0.40MnO3 and Sm0.55Sr0.45MnO3

Abstract

We report investigations of the intrinsic electroresistance of polycrystalline Sm0.60Sr0.40MnO3 and Sm0.55Sr0.45MnO3 that are synthesized in the same way. These experiments were carried out with excitation using short current pulses, and are analyzed with the goal of drastically reducing the contribution of Joule heating on the electroresistance. We find that the changes of the intrinsic electroresistance with the current density are much more significant in Sm0.60Sr0.40MnO3 compared to Sm0.55Sr0.45MnO3. These results are compared with other recent measurements of the electroresistance in the same compositions. The possible underlying mechanisms for our observed composition-dependent changes are also discussed.