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arXiv · 0903.3272

Skyrmions and Anomalous Hall Effect in a Dzyloshinskii-Moriya Spiral Magnet

Su Do Yi·Shigeki Onoda·Naoto Nagaosa·Jung Hoon Han
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Abstract

Monte Carlo simulation study of a classical spin model with Dzylosinskii-Moriya interaction and the spin anisotropy under the magnetic field is presented. We found a rich phase diagram containing the multiple spin spiral (or skyrme crystal) phases of square, rectangular, and hexagonal symmetries in addition to the spiral spin state. The Hall conductivity $σ_{xy}$ is calculated within the $sd$ model for each of the phases. While $σ_{xy}$ is zero in the absence of external magnetic field, applying a field strength $H$ larger than a threshold value $H_c$ leads to the simultaneous onset of nonzero chirality and Hall conductivity. We find $H_c = 0$ for the multiple spin spiral states, but $H_c > 0$ for a single spin spiral state regardless of the field orientation. Relevance of the present results to MnSi is discussed.

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Su Do Yi, Shigeki Onoda, Naoto Nagaosa, Jung Hoon Han. 2009-03-19. Skyrmions and Anomalous Hall Effect in a Dzyloshinskii-Moriya Spiral Magnet. https://doi.org/10.1103/physrevb.80.054416

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