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Topological Nature of Anomalous Hall Effect in Ferromagnet

Masaru Onoda·Naoto Nagaosa
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Abstract

The anomalous Hall effect in two-dimensional ferromagnets is discussed to be the physical realization of the parity anomaly in (2+1)D, and the band crossing points behave as the topological singularity in the Brillouin zone. This appears as the sharp peaks and the sign changes of the transverse conductance $σ_{xy}$ as a function of the Fermi energy and/or the magnetization. The relevance to the experiments including the three dimensional systems is also discussed.

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Masaru Onoda, Naoto Nagaosa. 2001-10-24. Topological Nature of Anomalous Hall Effect in Ferromagnet. https://doi.org/10.1143/jpsj.71.19

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