Magnonic band gap design by the edge modulation of micro-sized waveguides

The potential to control the number of the spin-wave band gaps of a magnonic crystal (MC) by variation of its geometry is investigated by numerical simulations. The MC is represented by a micro-sized planar ferromagnetic waveguide with periodically variable width. By choosing a step-like or sinusoidal variation of the width, the MC reveals multiple or single band gaps, respectively. This allows for additional degrees of freedom in the design of MC-based microwave filters and phase shifters with desired characteristics. The MCs' band gaps have been studied in the space and frequency domains exploring the spin-wave spectrum dependence on the probing position inside the MC.