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arXiv · 1212.3053

Coherent sliding dynamics and spin motive force driven by crossed magnetic fields in chiral helimagnet

Abstract

We demonstrated that the chiral soliton lattice formed out of a chiral helimagnet exhibits coherent sliding motion by applying a time-dependent magnetic field parallel to the helical axis, in addition to a static field perpendicular to the helical axis. To describe the coherent sliding, we use the collective coordinate method and numerical analysis. We also show that the time-dependent sliding velocity causes a time-varying Berry cap which causes the spin-motive-force. A salient feature of the chiral soliton lattice is appearance of the strongly amplified spin motive force which is directly proportional to the macroscopic number of solitons (magnetic kinks).

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Jun-ichiro Kishine, I. G. Bostrem, A. S. Ovchinnikov, Vl. E. Sinitsyn. 2012-12-13. Coherent sliding dynamics and spin motive force driven by crossed magnetic fields in chiral helimagnet. https://doi.org/10.1103/physrevb.86.214426

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