Nonlinear signal processing with magnonic superlattice with two periods

In this work, we provide investigations of nonlinear spin wave propagation in magnonic superlattice. Magnonic superlattice is a ferromagnetic film loaded on a dielectric ceramic substrate with the copper grating with two periods. It is shown that a superlattice with two periods allows the formation of narrower bandgaps as compared to magnonic crystal with one period. Nonlinear effects, such as the generation of spin wave excitations at half-frequency, caused by first-order parametric processes, and a nonlinear shift of the bandgap, caused by a change in the longitudinal component of magnetization with an increase in the input signal power, are revealed. For the experimental study, the Brillouin light scattering spectroscopy was used, and the theoretical model was built using the transfer matrix method.