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Spin Chirality Fluctuation and Anomalous Hall Effect in Itinerant Ferromagnets

Shigeki Onoda·Naoto Nagaosa
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Abstract

The anomalous Hall effect due to the spin chirality order and fluctuation is studied theoretically in a Kondo lattice model without the relativistic spin-orbit interaction. Even without the correlations of the localized spins, $σ_{xy}$ can emerge depending on the lattice structure and the spin anisotropy. We reveal the condition for this chirality-fluctuation driven mechanism for $σ_{xy}$. Our semiquantitative estimates for a pyrochlore oxide Nd$_2$Mo$_2$O$_7$ give a finite $σ_{xy} \sim 10 \Ohm^{-1} \cm^{-1}$ together with a high resistivity $ρ_{xx} \sim 10^{-4}-10^{-3} \Ohm \cm$, in agreement with experiments.

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Shigeki Onoda, Naoto Nagaosa. 2002-11-14. Spin Chirality Fluctuation and Anomalous Hall Effect in Itinerant Ferromagnets. https://doi.org/10.1103/physrevlett.90.196602

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