Skyrmion Strings and Anomalous Hall Effect in Double Exchange Systems

We perform Monte Carlo simulations to obtain quantitative results for the anomalous Hall resistance, R_A, observed in colossal magnetoresistance manganites. R_A arises from the interaction between the spin magnetization and topological defects via spin-orbit coupling. We study these defects and how they are affected by the spin-orbit coupling within the framework of the double exchange model. The obtained anomalous Hall resistance is, in sign, order of magnitude and shape, in agreement with experimental data.