论文部分内容阅读
采用电化学沉积在多孔氧化铝模板中制备了NiCo/Cu多层结构纳米线,并使用扫描电子显微镜(SEM)和透射电子显微镜(TEM)表征了纳米线的形貌和微观结构。透射电子显微镜的结果表明,通过控制阶梯电位时间,制备的铁磁层厚度为100nm,非铁磁层厚度为10nm。结合选区电子衍射技术(SAED)与X射线衍射分析技术(XRD),确定多层纳米线的晶格结构是面心立方(FCC)。在分析多层纳米阵列的微观结构之后,使用振动样品磁强计(VSM)测量磁滞回线。结果表明,随着Co含量的增加,多层纳米线的矫顽力升高。当多层纳米线中Co含量为10%和30%时,易磁化轴垂直于纳米线,当Co含量为70%和90%时,易磁化轴平行于纳米线。最后,对纳米线磁化翻转机制进行微磁学模拟分析得出,当外加磁场垂直于纳米线时,磁化反转机制是形核机制;当外加磁场平行于纳米线时,磁化反转机制是卷曲机制。
NiCo / Cu multilayer nanowires were prepared by electrochemical deposition in a porous alumina template. The morphology and microstructure of the nanowires were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results of transmission electron microscopy showed that the thickness of the ferromagnetic layer prepared was 100 nm and the thickness of the non-ferromagnetic layer was 10 nm by controlling the step potential time. Combined with the selected area electron diffraction (SAED) and X-ray diffraction analysis (XRD), the lattice structure of multilayer nanowires is confirmed as FCC. After analyzing the microstructure of a multilayer nanowire array, a hysteresis loop was measured using a vibrating sample magnetometer (VSM). The results show that with the increase of Co content, the coercivity of multilayer nanowires increases. When the content of Co is 10% and 30%, the axis of easy magnetization is perpendicular to the nanowires. When the Co content is 70% and 90%, the axis of easy magnetization is parallel to the nanowires. Finally, the magnetization reversal mechanism of nanowires is analyzed by micro-magnetic simulation. It is found that the magnetization reversal mechanism is the nucleation mechanism when the applied magnetic field is perpendicular to the nanowires. When the applied magnetic field is parallel to the nanowires, the magnetization reversal mechanism is curly mechanism.