Two-Dimensional Magnonic Crystal With Periodic Thickness Variation in YIG Layer for Magnetostatic Volume Wave Propagation

The propagation characteristics of magnetostatic volume waves (MSVWs), namely, magnetostatic forward volume waves (MSFVWs) and magnetostatic backward volume waves (MSBVWs), in two-dimensional (2-D) magnonic crystals (MCs) with periodic thickness variation of square lattice in YIG layer are reported. The theoretical approach based on Walker's equation was employed to determine the bandgaps associated with the MSVWs. Experiments were conducted on a 2-D MC with periodic square lattices in YIG layer thickness to measure both the magnetic field-tuned and propagation direction-dependent bandgaps. A very good agreement between the measured and the calculated results was obtained.