Nam Chunghee
J Nanosci Nanotechnol. 2015 Oct;15(10):7620-3. doi: 10.1166/jnn.2015.11158.
We show that a type of magnetic domain walls (DWs) can be monitored by anisotropic magnetoresistance (AMR) measurements due to a specific DW volume depending on the DW type in NiFe magnetic wires. A circular DW injection pad is used to generate DWs at a low magnetic field, resulting in reliable DW introduction into magnetic wires. DW pinning is induced by a change of DW energy at an asymmetric single notch. The injection of DW from the circular pad and its pinning at the notch is observed by using AMR and magnetic force microscope (MFM) measurements. A four-point probe AMR measurement allows us to distinguish the DW type in the switching process because DWs are pinned at the single notch, where voltage probes are closely placed around the notch. Two types of AMR behavior are observed in the AMR measurements, which is owing to a change of DW structures. MFM images and micromagnetic simulations are consistent with the AMR results.
我们表明，由于特定的磁畴壁（DWs）体积取决于镍铁磁线中DW的类型，一种类型的磁畴壁可以通过各向异性磁阻（AMR）测量进行监测。圆形DW注入垫用于在低磁场下产生DW，从而将DW可靠地引入磁线。DW钉扎是由不对称单缺口处DW能量的变化引起的。通过使用AMR和磁力显微镜（MFM）测量，观察到从圆形垫注入DW及其在缺口处的钉扎。四点探针AMR测量使我们能够在切换过程中区分DW类型，因为DW被钉扎在单缺口处，电压探针紧密放置在缺口周围。在AMR测量中观察到两种类型的AMR行为，这是由于DW结构的变化。MFM图像和微磁模拟与AMR结果一致。
