Metastable magnetic domain walls in cylindrical nanowires

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:381

Article

Ferguson, C. A.¹  MacLaren, D. A.¹  McVitie, S.¹ 

[1] Univ Glasgow, Sch Phys & Astron, SUPA, Glasgow G12 8QQ, Lanark, Scotland

关键词: Magnetic nanowires;    Phase diagram;    Domain wall;    Magnetic nanotubes;    Domain wall structure;   

DOI  :  10.1016/j.jmmm.2015.01.027

来源: Elsevier

【 摘 要 】

The stability of the asymmetric domain wall (ATDW) in soft magnetic cylindrical nanowires and nanotubes is investigated using micromagnetic simulations. Our calculated phase diagram shows that for cylindrical permalloy nanowires, the transverse domain wall (TDW) is the ground state for radii below 20 nm whilst the Bloch point wall (BPW) is favoured in thicker wires. The ATDW stabilises only as a metastable state but with energy close to that of the BPW. Characterisation of the DW spin structures reveals that the ATDW has a vortex-like surface spin state, in contrast to the divergent surface spins of the TDW. This results in lowering of surface charge above the critical radius. For both cylindrical nanotubes and nanowires we find that ATDWs only appear to exist as metastable static states and are particularly suppressed in nanotubes due to an increase in magnetostatic energy. (C) 2015 The Authors. Published by Elsevier B.V.

【 授权许可】

Free