Effect of End Shape on Magnetization Reversal Dynamics of NiFe Nanofilm Elements

doi:10.19596/j.cnki.1001-246x.7655

Abstract

Abstract: Magnetization reversal dynamics of NiFe nanofilm elements were studied with micromagnetic simulation. Magnetization reversal and spin-wave dynamic properties are effectively tuned by tailoring end shape of NiFe nanofilm elements. As magnetization reversal occurs,it is accompanied by a soft magnetic mode whose spacial symmetry determines initial steps(onset) of microscopic magnetization phase transitions path. There exists a critical tapered parameter h₀. For elements with tapering parameter h<h₀, reversal is achieved by nucleation of reversed domain at element ends and its irreversible expansion through domain wall movement toward central area of element. It is softening of edge mode that triggers magnetization reversal. For elements with h ≥ h₀, reversal is realized by quasi-uniform rotation of magnetization, which is induced by softening of fundamental mode.>

Key words: spin wave, magnetization reversal, micromagnetic simulation, NiFe nanofilm

CLC Number:

O482.51

ZHANG Guangfu, DENG Yangbao, TIAN Ye, JIANG Lianjun. Effect of End Shape on Magnetization Reversal Dynamics of NiFe Nanofilm Elements[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2018, 35(3): 373-378.

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