Study of the magnetization behavior of ferromagnetic nanowire array: Existence of growth defects revealed by micromagnetic simulations

• Published in: Journal of magnetism and magnetic materials Vol. 401; pp. 378 - 385
• Main Authors: Nguyen Vien, G., Rioual, S., Gloaguen, F., Rouvellou, B., Lescop, B.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-03-2016; Elsevier
• Subjects: Arrays; Chemical Sciences; Coercive force; Coercivity; Crystal defects; Ferromagnetic nanowires; Magnetic properties; Magnetization; Magnetization process; Micromagnetic modeling; Nanostructure; Nanowires; Simulation; Ferromagnetic nanowires; Magnetization process; Micromagnetic modeling; Coercivity
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2015.10.070

High aspect ratio nanowires were electrodeposited in nanoporous anodic alumina template by a potentiostatic method. The angular dependence of the coercive field and remanence magnetization extracted from magnetometry measurements are compared with micromagnetic simulations. Inclusion of magnetostatic interactions between Ni nanowires in simulations is required to explain some of the properties of the magnetization reversal. However, it is not sufficient to reproduce fully the angular dependence of the coercive field. Due to the polycrystalline nature of nanowires and thus to the presence of grain boundaries, defects are included in simulations. A good agreement between theory and experiment is then clearly highlighted, in particular in the nanowire easy axis direction. The achieved results allow a description of several experimental data published in the literature and consequently to get a better understanding of reversal mechanisms that operate in such nanowire arrays. A complementary study of composite nanowire array is successfully performed to prove the adequacy of the simulations method to describe the magnetic properties of nanowire array.
•High axial squareness nanowire array are synthetized by a potentiostatic method.•Nanowires are modeled as non-ideal magnetic particles.•Segmentation of nanowire is required to describe the angular dependence of coercivity.•Respective role of magnetostatic coupling and nanowire segmentation in nanowire array are studied.•Micromagnetic simulations lead to quantitative agreement for well-defined composite nanowire array.