Metastable magnetic domain walls in cylindrical nanowires
Metastable magnetic domain walls in cylindrical nanowires
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DOI：
10.1016/j.jmmm.2015.01.027
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发表时间：
2015-05-01
影响因子：
2.7
通讯作者：
McVitie, S.
中科院分区：
文献类型：
--
作者：
Ferguson, C. A.;MacLaren, D. A.;McVitie, S.
利用微磁学模拟研究了圆柱形软磁纳米线和纳米管中非对称畴壁的稳定性。我们计算的相图表明，对于圆柱形坡莫合金纳米线，横向畴壁（TDW）是基态的半径低于20 nm，而布洛赫点壁（BPW）有利于在较厚的线。ATDW仅稳定为亚稳态，但能量接近BPW。DW自旋结构的表征表明，ATDW具有涡旋状的表面自旋状态，与TDW的发散表面自旋相反。这导致表面电荷低于临界半径。对于圆柱形的纳米管和纳米线，我们发现，ATDWs似乎只存在亚稳态，特别是抑制在纳米管由于静磁能的增加。(C)2015作者由爱思唯尔公司出版
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.