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arXiv · 1409.7869

Universal Ratio of Intrinsic Resistivities of Spin Helix in B20 (Fe-Co)Si Magnets

S. X. Huang·Jian Kang·Fei Chen·Jiadong Zang·G. J. Shu·F. C. Chou·S. V. Grigoriev·V. A. Dyadkin·C. L. Chien
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Abstract

The B20 magnets with the Dzyaloshinskii-Moriya (D-M) interaction exhibit spin helix and Skyrmion spin textures unattainable in traditional Heisenberg ferromagnets. We have determined the intrinsic resistivity of the spin helix, which is a macroscopic Bloch domain wall, in B20 (Fe-Co)Si magnets. We found a universal resistance ratio of gamma = 1.35 with current parallel and perpendicular to the helix, independent of composition and temperature. This gamma value is much smaller than 3, the well-known minimum value for domain wall resistivity in traditional ferromagnets, due to the significant spin-orbit coupling in the B20 magnets.

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S. X. Huang, Jian Kang, Fei Chen, Jiadong Zang, G. J. Shu, F. C. Chou, S. V. Grigoriev, V. A. Dyadkin, C. L. Chien. 2014-09-28. Universal Ratio of Intrinsic Resistivities of Spin Helix in B20 (Fe-Co)Si Magnets. https://arxiv.org/abs/1409.7869

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