Ferromagnetic resonance in submicron metallic wires

We report on the microwave properties of a nanostructured magnetic planar substrate. It consists of an array of parallel magnetic nanowires constituted of nickel, cobalt or Ni/Fe alloy embedded in a porous polymer membrane. Experiments consist of transmission measurements carried out on microwave stripline. Measurements were performed at frequencies ranging from 100 MHz to 40 GHz and under static magnetic fields up to 5.6 kOe applied along the wire axis. Resonance phenomena have been observed in the presence but also in the absence of the DC magnetic field at frequencies which depend on the nature of the material and the applied static magnetic field. Results are consistent with those expected for a ferromagnetic resonance (FMR) experiment and the observed behaviors are analyzed in the framework of the classical FMR theory