Domain-wall dynamics for an in-plane magnetized thin film with a large perpendicular hard-axis anisotropy including the Dzyaloshinskii-Moriya interaction

Article

关键词: WEAK FERROMAGNETISM;    DIFFUSION;    MOTION;    NANOWIRES;   

DOI  :  10.1103/PhysRevB.98.134429

来源: SCIE

【 摘 要 】

We consider a thin ferromagnetic layer to which an external field or a current are applied along an in-plane easy axis. The perpendicular hard-axis anisotropy constant is large so that the out-of-plane magnetization component is much smaller than the in-plane components. A perturbation approach is used to obtain the profile and velocity of the moving domain wall. The dynamics of the in-plane components of the magnetization is governed by a reaction diffusion equation which determines the speed of the profile. We find a simple analytic expression for the out-of-plane magnetization showing a symmetric distortion due to the motion in addition to the asymmetric component due to the Dzyaloshinskii-Moriya interaction. The results obtained complement previous studies in which either the Dzyalozhinskii vector or the out-of-plane hard-axis anisotropy were assumed small. In the regime studied the Walker breakdown is not observed but the reaction diffusion dynamics predicts a slowing down of the domain wall for a sufficiently large magnetic field. The transition point depends on the applied field, saturation magnetization, and easy-axis anisotropy.

【 授权许可】

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