Starting from the assumption that ferromagnetically correlated regions exist in manganites even in the absence of long-range magnetic order, we construct a model of charge transfer due to the spin-dependent tunnelling of charge carriers between such regions. This model allows us to analyze the temperature and magnetic field dependence of resistivity, magnetoresistance, and magnetic susceptibility of phase-separated manganites in the temperature range corresponding to non-metallic behavior. The comparison of theoretical and experimental results reveals the main characteristics of the phase-separated state.
@article{arxiv.cond-mat/0312294,
title = {Spin-dependent transport in phase-separated manganites},
author = {K. I. Kugel and A. L. Rakhmanov and A. O. Sboychakov and M. Yu. Kagan and I. V. Brodsky and A. V. Klaptsov},
journal= {arXiv preprint arXiv:cond-mat/0312294},
year = {2007}
}
Comments
18 pages, 12 figures, submitted to Journal of Experimental and Theoretical Physics (Zh. Eksp. Teor. Fiz., v.125 (2), 2004)