Structural and magnetic properties of (FePt)1−xCux nanowires

Highly ordered (FePt)1−xCux nanowire arrays have been fabricated successfully by double-pulse electro-deposition into the pores of a porous anodic aluminum oxide template. We have found that the addition of Cu to FePt nanowires is an effective approach for reducing the ordering temperature of FePt. The coercivity of the (FePt)88Cu12 nanowire arrays is around 2 kOe after annealing at 300 °C for 1 h, whereas that of FePt nanowire arrays shows several hundred Oe. X-ray diffraction characterization showed that only one set of L10 diffraction peaks appeared and no elemental Cu diffraction peaks were visible. This result, along with a varying c/a-lattice parameter ratio, suggests that Cu substitutes Fe or Pt in the ternary FePtCu alloy nanowires.