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arXiv · 1707.00397

Chiral helimagnetic state in a Kondo lattice model with the Dzyaloshinskii-Moriya interaction

Shun Okumura·Yasuyuki Kato·Yukitoshi Motome
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Abstract

Monoaxial chiral magnets can form a noncollinear twisted spin structure called the chiral helimagnetic state. We study magnetic properties of such a chiral helimagnetic state, with emphasis on the effect of itinerant electrons. Modeling a monoaxial chiral helimagnet by a one-dimensional Kondo lattice model with the Dzyaloshinskii--Moriya interaction, we perform a variational calculation to elucidate the stable spin configuration in the ground state. We obtain a chiral helimagnetic state as a candidate for the ground state, whose helical pitch is modulated by the model parameters: the Kondo coupling, the Dzyaloshinski--Moriya interaction, and electron filling.

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Shun Okumura, Yasuyuki Kato, Yukitoshi Motome. 2017-07-03. Chiral helimagnetic state in a Kondo lattice model with the Dzyaloshinskii-Moriya interaction. https://doi.org/10.1016/j.physb.2017.08.047

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