Effect of crystallinity on the magnetoresistance in perovskite manganese oxide thin films

Publication Type

Journal Article

Authors

DOI

Abstract

We report our study of the effect of crystallinity on the magnetoresistance in epitaxial and polycrystaliine La2/3Ba1/3MnO3 and La2/3Ca1/3MnO3 thin films. Magnetoresistance in epitaxial films exhibits field dependence and temperature dependence similar to bulk single crystals and sintered bulk ceramics. The polycrystalline films exhibit a markedly different behavior. The magnetoresistance in this case shows either a monotonic increase or saturation with decreasing temperature in contrast to that of epitaxial films in which the magnetoresistance peaks close to the ferromagnetic transition temperature. The field dependence in the polycrystalline films is also remarkably different. At low fields, we observe a sharp drop in resistance followed by a more gradual decrease at higher fields. Our data suggest that in addition to the intrinsic magnetoresistance, grain-boundary transport contributes significantly to the magnetoresistance in polycrystalline films. © 1997 American Institute of Physics.

Journal

Applied Physics Letters

Volume

71

Year of Publication

1997

ISSN

00036951

Notes

cited By 134

Research Areas