Preparation and magnetic behavior of arrays of electrodeposited Co nanowires

Cobalt nanowires have been synthesized by electrodeposition into porous track-etched polycarbonate membranes with a quoted pore diameter of Dp approximate to 200-400nm and a thickness of L approximate to 7mum. Magnetization curves and torque experiments of arrays of Co wires confirm that when the lengths of the wires are increased a crossover takes place from a parallel easy direction of magnetization towards an easy direction perpendicular to the axis of the wire. This change in the easy direction of magnetization is analyzed considering the competition between demagnetizing field, magnetocrystalline anisotropy, and dipolar interaction among wires. (C) 2002 Elsevier Science B.V. All rights reserved.