IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Magnetic Interfaces and Nanostructures Tuesday Sessions
       Session MI-TuP

Paper MI-TuP12
Annealing Effect on Structure and Magnetism of CoNi Pattern Quantum Dots

Tuesday, October 30, 2001, 5:30 pm, Room 134/135

Session: Emerging Materials & Nanostructures Poster Session
Presenter: H.L. Li, Lanzhou University, P. R. China
Authors: H.L. Li, Lanzhou University, P. R. China
C.W. Wang, Lanzhou University, P. R. China
D.H. Qin, Lanzhou University, P. R. China
M.K. Li, Lanzhou University, P. R. China
Correspondent: Click to Email
NiCo alloy nanowires were prepared by AC electrodeposition into self-assembled porous anodic alumina template. Then the sample was annealed at 500 °C, 6 hours, with argon as protected gas. The composition, microstructure and magnetism of samples used in this work were characterized by atom absorbed spectrum, transmission electron microscopy (TEM), scanning electron microscopy (SEM), x-ray diffraction (XRD), and vibrating sample magnetometer (VSM). XRD results showed that there were preferred orientation in CoNi nanowire arrays with Ni content range from 0.2 to 0.8 during electrodeposition, while random orientation was observed after the sample was heat-treated. Though the shape anisotropy was very high in the sample, it is found that the squareness (Mr/Ms) of the hysteresis of the samples (Ni content is in the range of 0.2 to 0.8) was only about 0.6 before annealing, and increased to about 0.9 after annealing. As its high bit density, such media may be used as high-density quantum magnetic disks. A qualitative discussion was given and explanation of reversal mechanism was offered in term of localized magnetization model.