Tuning the magnetic properties of multisegmented Ni/Cu electrodeposited nanowires with controllable Ni lengths

• Tipo: Artigo em Revista Científica Internacional
• Data: 2016

Autores

Susano, M (Autor) Outra; proenca, m. p. (Autor) FCUP; Moraes, S (Autor) Outra; Sousa, CT (Autor) FCUP; araujo, j. p. (Autor) FCUP

Revista

Título: Nanotechnology

Vol. 27

Página Final: 335301

ISSN: 0957-4484

Editora: Institute of Physics Publishing

Indexação

ISI Web of Knowledge - 40 Citações

Scopus - 43 Citações

Outras Informações

ID Authenticus: P-00K-P3V

DOI: 10.1088/0957-4484/27/33/335301

Abstract (EN): The fabrication of segmented Ni/Cu nanowires (NWs), with tunable structural and magnetic properties, is reported. A potentiostatic electrodeposition method with a single electrolytic bath has been used to fabricate multisegmented Ni/Cu NWs inside a highly hexagonally ordered anodic nanoporous alumina membrane, with diameters of 50 nm and Ni segment lengths (L-Ni) tuned from 10 nm up to 140 nm. The x-ray diffraction results evidenced a strong dependence of the Ni NWs crystallographic face-centered-cubic (fcc) texture along the [220] direction on the aspect ratio of the NWs. The magnetic behavior of the multisegmented Ni/Cu NW arrays, as a function of the magnetic field and temperature, is also studied and correlated with their structural and morphological properties. Micromagnetic simulations, together with the experimental results, showed a dominant antiferromagnetic coupling between Ni segments along the wire length for small low aspect-ratio magnetic segments. When increasing the Ni segments' length, the magnetic interactions between these along the wire became stronger, favouring a ferromagnetic coupling. The Curie temperature of the NWs was also found to strongly depend on the Ni magnetic segment length. Particularly the Curie temperature was found to be reduced 75 K for the 20 nm Ni segments, following the finite-size scaling relation with xi(0) = 8.1 angstrom and gamma = 0.48. These results emphasize the advantages of using a template assisted method to electrodeposit multilayer NWs, as it allows an easy tailor of the respective morphological, chemical, structural and magnetic properties.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 10