Spin-waves generation at the thickness step of yttrium iron garnet film

Abstract

We report on the experimental observation of short, exchange-dominated spin waves (EDSW) generation by a thickness step in the ferrite waveguide under microwave pumping. This effect was explored both experimentally (using mirco-Brillouin light scattering technique) and theoretically (by micromagnetic simulation) for the sample magnetized along the step and for two cases of pumping: a uniform microwave pumping of the step and its pumping through a magnetostatic surface wave (MSSW) traveling across the step. It was shown that efficiency of EDSW generation caused by MSSW scattering on the thickness step increases with the frequency (or wave number) while for the case of the uniform pumping, the generation efficiency demonstrates the opposite behavior.