Author: JunweiZhang, Yong Peng,HongbinMa, Senfu Zhang, Yang Hu, Xue Zeng, Xia Deng, Chaoshuai Guan,Rongrong Chen, Yue Hu, Abdul Karim, Kun Tao, Mingjie Zhang, andXixiang Zhang
The accurate magnetoresistance (MR) measurement of individualnanostructures is essential and important for either the enrichmentof fundamental knowledge of the magnetotransport mechanism or thefacilitation of desired design of magnetic nanostructures for varioustechnological applications. Herein, we report a deep investigation onthe magnetotransport mechanism of a single CoCu/Cu multilayerednanowire via direct MR measurement using our inventedmagnetotransport instrument in situ scanning electron microscope.Off-axis electron holography experiments united with micromagneticsimulation prove that the CoCu layers in CoCu/Cu multilayerednanowires form a single-domain structure, in which the alignment ofmagnetic moments is mainly determined by shape anisotropy. The MR ofthe single CoCu/Cu multilayered nanowire is measured to be only 1.14%when the varied external field is applied along the nanowire lengthaxis, which matches with the theoretical prediction of the granularfilm model. Density functional theory calculations further disclosethat spin-dependent scattering at the interface between magnetic andnonmagnetic layers is responsible for the intrinsic magnetotransportmechanism.
Keywords: magnetotransport mechanism; individual nanostructures; off-axiselectron holography; magnetotransport instrument; in situ scanningelectron microscopy