Department of Physics, Seoul National University, Seoul, Republic of Korea.
Nanotechnology. 2011 Feb 25;22(8):085201. doi: 10.1088/0957-4484/22/8/085201. Epub 2011 Jan 17.
We have found that the depinning field of domain walls (DWs) in permalloy (Ni(81)Fe(19)) nanowires can be experimentally controlled by interactions between magnetic stray fields and artificial constrictions. A pinning geometry that consists of a notch and a nanobar is considered, where a DW traveling in the nanowire is pinned by the notch with a nanobar vertical to it. We have found that the direction of magnetization of the nanobar affects the shape and local energy minimum of the potential landscape experienced by the DW; therefore, the pinning strength strongly depends on the interaction of the magnetic stray field from the nanobar with the external pinning force of the notch. The mechanism of this pinning behavior is applied for the instant and flexible control of the pinning strength with respect to various DW motions in DW-mediated magnetic memory devices.
我们发现，通过磁 stray 场与人工狭缝之间的相互作用，可以在实验上控制坡莫合金（Ni(81)Fe(19))纳米线中畴壁（DWs）的去钉扎场。考虑了一种由凹槽和纳米棒组成的钉扎几何形状，其中在纳米线中移动的 DW 被垂直于纳米棒的凹槽钉扎。我们发现，纳米棒的磁化方向会影响 DW 所经历的势景观的形状和局部能量最小值；因此，钉扎强度强烈依赖于来自纳米棒的磁 stray 场与凹槽的外部钉扎力之间的相互作用。这种钉扎行为的机制可用于在 DW 介导的磁存储器件中针对各种 DW 运动即时且灵活地控制钉扎强度。
