Magnetization and ferromagnetic resonance studies in Co/V multilayers

The magnetic properties of evaporated Co/V multilayer films have been studied by superconducting quantum interference device magnetometer and ferromagnetic resonance (FMR). The magnetization follows a quasi-linear temperature dependence, which reverts to a T 3/2 dependence further into the bulk. We attribute the quasi-linear temperature behavior to surface spin-wave modes created by a perpendicular surface anisotropy at the interface. The FMR spectra are obtained with the applied magnetic field parallel and perpendicular to the film plane at 300 K. The FMR linewidth of uniform mode, Δ H ⊥, for the perpendicular geometry, depends on the thickness of Co layer as t Co −2. From both FMR and torque magnetometer measurements, a positive value for Co/V interface anisotropy is obtained.