Magnetic properties of Ni nanowires in self-assembled arrays

Authors

M. Zheng, University of Nebraska-Lincoln
L. Menon, University of Nebraska-Lincoln
H. Zeng, University of Nebraska-Lincoln
Yi Liu, University of Nebraska-LincolnFollow
Supriyo Bandyopadhyay, University of Nebraska-LincolnFollow
Roger D. Kirby, University of Nebraska-LincolnFollow
David J. Sellmyer, University of Nebraska-LincolnFollow

Date of this Version

10-1-2000

Comments

Published in Phys. Rev. B 62, 12282–12286 (2000) [Issue 18 – 1 November 2000 ] © 2000 The American Physical Society. Used by permission.
URL: http://link.aps.org/abstract/PRB/v62/p12282
DOI: 10.1103/PhysRevB.62.12282

Abstract

Magnetic properties of Ni nanowires electrodeposited into self-assembled porous alumina arrays have been investigated. By anodizing aluminum in sulfuric acid and immersing the as-anodized template into phosphoric acid for different lengths of time, we are able to vary the diameters of the subsequently deposited nanowires between 8 and 25 nm. The coercivity measured along wire axis first increases with the wire diameter, reaches a maximum of 950 Oe near a diameter of 18 nm, and then decreases with further increase of wire diameter. The dependence of the magnetization of Ni nanowires is found to follow Bloch’s law at low temperature but with the Bloch exponent decreasing from the bulk value and the Bloch constant increasing from the bulk value by an order of magnitude.