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

• Type: Article in International Scientific Journal
• Date: 2016

Authors

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

Journal

Title: Nanotechnology

Vol. 27

Final page: 335301

ISSN: 0957-4484

Publisher: Institute of Physics Publishing

Indexing

ISI Web of Knowledge - 40 Citations

Scopus - 43 Citations

Other information

Authenticus ID: 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.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10