Disorder-Induced Resistive Anomaly Near Ferromagnetic Phase Transitions

Carsten Timm; M. E. Raikh; Felix von Oppen

doi:10.1103/physrevlett.94.036602

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Disorder-Induced Resistive Anomaly Near Ferromagnetic Phase Transitions

Carsten Timm·M. E. Raikh·Felix von Oppen

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Abstract

We show that the resistivity rho(T) of disordered ferromagnets near, and above, the Curie temperature T_c generically exhibits a stronger anomaly than the scaling-based Fisher-Langer prediction. Treating transport beyond the Boltzmann description, we find that within mean-field theory, dρ/dT exhibits a |T-T_c|^{-1/2} singularity near T_c. Our results, being solely due to impurities, are relevant to ferromagnets with low T_c, such as SrRuO3 or diluted magnetic semiconductors, whose mobility near T_c is limited by disorder.

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Carsten Timm, M. E. Raikh, Felix von Oppen. 2005-01-31. Disorder-Induced Resistive Anomaly Near Ferromagnetic Phase Transitions. https://doi.org/10.1103/physrevlett.94.036602

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