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Magnetotransport in manganites and the role of quantal phases II: Experiment

S. H. Chun·M. B. Salamon·P. D. Han·Y. Lyanda-Geller·P. M. Goldbart
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Abstract

As in conventional ferromagnets, the Hall resistivity rho_xy of a La_{2/3}(Ca,Pb)_{1/3}MnO_3 single crystal exhibits both ordinary and anomalous contributions at low temperature. However, these contributions, unexpectedly, have opposite signs. Near Tc, the ordinary contribution is no longer evident and rho_xy is solely determined by the sample magnetization, reaching an extremum at approximately 40% of the saturated magnetization. A new model for the anomalous Hall effect, incorporating the quantal phase accumulated by double-exchange, three-site hopping reproduces this result. Below Tc, rho_xy reflects the competition between normal and anomalous Hall effects.

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S. H. Chun, M. B. Salamon, P. D. Han, Y. Lyanda-Geller, P. M. Goldbart. 1999-04-22. Magnetotransport in manganites and the role of quantal phases II: Experiment. https://doi.org/10.1103/physrevlett.84.757

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