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).