Magnetostatic surface wave scattering in geometrically modified ferromagnetic films

A problem of interest in the area of Magnonics is the propagation of spin waves in thin ferromagnetic films or stripes. At present, this interest is related with the possibility of using spin waves as a practical mechanism of transfering information within nano-devices, either coded in their amplitudes or phases. In particular, to elucidate the effect of obstacles in their propagation is of relevance for practical applications. The present study focuses on a particular geometry and spin wave modes of interest: we consider the propagation of magnetostatic Damon-Eshbach surface waves in ferromagnetic films with surfaces that have geometric modulations perpendicular to the direction of propagation of the waves. In particular, we study the scattering of these surface wave of high group velocity by bumps and depressions, with a focus on transmitted energy and the presence of eventual localized modes. We study the propagations of these modes through the Green-extinction theorem, that renders sets of integral equations for the modes evaluated on the geometrically modified surfaces.