Effects of surface morphology on magnetic properties of Ni nanowire arrays in self-ordered porous alumina

Authors

H. Zeng, University of Nebraska - Lincoln
Stevem A. Michalski, University of Nebraska-LincolnFollow
Roger D. Kirby, University of Nebraska-LincolnFollow
David J. Sellmyer, University of Nebraska-LincolnFollow
L. Menon, University of Nebraska - Lincoln
Supriyo Bandyopadhyay, University of Nebraska-LincolnFollow

Date of this Version

1-18-2002

Comments

Published in Journal Of Physics: Condensed Matter 14 (2002), pp. 715–721. Copyright © 2002 Institute of Physics/IOP Publishing. Used by permission.

Abstract

Ni nanowire arrays were produced by electrodeposition of Ni into self-assembled porous anodic alumina templates. With different anodization voltages, the wires show different surface morphologies. The temperature dependence of the coercivity and activation volume of wires with regular shape can be explained by thermal activation over an energy barrier with a 3/2 power dependence on the field. The wires with irregular surface morphologies show abnormal temperature dependences of the coercivity and activation volume. Possible mechanisms for these behaviors are discussed.