Engineering Magnetic Domain-Wall Structure in Permalloy Nanowires
Engineering Magnetic Domain-Wall Structure in Permalloy Nanowires
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DOI：
10.1103/physrevapplied.3.034008
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发表时间：
2015-03-26
影响因子：
4.6
通讯作者：
McVitie, S.
中科院分区：
文献类型：
--
作者：
Benitez, M. J.;Basith, M. A.;McVitie, S.
利用聚焦离子束显微镜，我们在由Cr(3nm)/ permalalloy (10nm)/Cr（5nm）组成的500 nm宽的纳米线中创建了非地形特征，提供了对畴壁结构、尺寸和钉接强度的可控修改。钉钉位置由线性缺陷组成，其中磁性能由直径约为10 nm的Ga+离子探针修饰。对辐照引起的结构、化学和磁性变化进行了详细的研究，表明修饰区域的宽度类似于40-50 nm，使用扫描-透射-电子显微镜模式的亮场成像、电子能量损失光谱和差相对比成像在像差校正（Cs）仪器上进行。利用洛伦兹透射电子显微镜的菲涅耳模式研究了畴壁行为，观察了脱屑强度和结构随辐照剂量和线取向的变化。我们提出了基于辐照缺陷的微磁模拟及其对畴壁能量项的影响的这种行为的理解。
Using a focused-ion-beam microscope, we create nontopographic features that provide controlled modification of domain-wall structure, size, and pinning strength in 500-nm-wide nanowires composed from Cr(3 nm)/permalloy(10 nm)/Cr(5 nm). The pinning sites consist of linear defects where magnetic properties are modified by a Ga+-ion probe of diameter similar to 10 nm. Detailed studies of the structural, chemical, and magnetic changes induced by the irradiation, which show the modified region to be similar to 40-50 nm wide, are performed using scanning-transmission-electron-microscopy modes of bright-field imaging, electron-energy-loss spectroscopy, and differential-phase-contrast imaging on an aberration corrected (Cs) instrument. The Fresnel mode of Lorentz-transmission-electron microscopy is used for studies of domain-wall behavior, where we observe changes in depinning strength and structure with irradiation dose and line orientation. We present an understanding of this behavior based upon micromagnetic simulation of the irradiated defects and their effect on the energy terms for the domain walls.