Phys. Rev. B 72, 024453 (2005)

M. Ziese and A. Bollero, I. Panagiotopoulos, N. Moutis

Abstract

Measurements of the magnetoconductance of La_0.7Sr_0.3MnO₃ pressed powder samples in both the low and high field regime are reported. The magnetoconductance was calculated in a model based on inelastic tunneling via Mn sites situated in the tunneling barrier. This model satisfactorily accounts for the strong decrease of the low field magnetoconductance as a function of temperature due to spin depolarization in the inelastic tunneling processes. The susceptibility of the tunneling barrier was derived by two different methods showing the consistency of the model.