CONICET | Buscador de Institutos y Recursos Humanos

Nanoporous anodic alumina films on Al substrates have been used as templates for the growth of electrodeposited Ni nanowires. The nanowire diameter ranges between 35 and 65 nm, and the hexagonal symmetry lattice constant is 105 nm. The magnetization curves for these nanowire arrays with and without the Al substrate have been measured in a temperature range from 5 to 300 K, from which the effective magnetic anisotropy, coercivity, and remanence have been determined. The effective easy magnetization axis changes from parallel to perpendicular to the Ni nanowire axis as temperature decreases, as a result of the magnetocrystalline and the magnetoelastic anisotropy terms, arising from the different thermal expansion coefficients of the ferromagnetic nanowires, the alumina and Al.