Surface roughness induced extrinsic damping in thin magnetic films

The ferromagnetic relaxation caused by the surface roughness induced 2-magnon scattering is investigated. Approximate analytical solution predicts nonexponential decay of the uniform precession excitations of the form exp{-\t/tau(3/2)\(3/2)}. This behavior as well as the dependence of the decay time tau(3/2) on roughness parameters are confirmed by micromagnetic simulations.