Edge modes in strip-loaded bilayer YIG waveguides

Abstract

Magnonics utilizes spin waves - the collective precession of magnetic moments—for the ultra-low-power transmission, processing, and storage of information, offering a viable alternative to traditional CMOS electronics. A key challenge in this field is tailoring the spin-wave mode structure and achieving selective excitation of localized states. In this work, we investigate edge modes in strip-loaded bilayer magnetic waveguides based on yttrium iron garnet (YIG) films with differing saturation magnetizations. Using micromagnetic simulations within the MuMax3 package based on the Landau-Lifshitz-Gilbert equation, we analyzed a system comprising a bottom YIG film and a symmetrically positioned top strip under a Damon-Eshbach magnetostatic configuration.The simulations reveal that the superposition of demagnetizing fields from both layers creates significant local reductions in the internal magnetic field near the boundaries of the top strip. These potential wells facilitate the efficient excitation of localized edge modes whose frequencies lie below the Damon-Eshbach geometry band. Spatial mapping of the mz magnetization component confirms the stable propagation of these edge states along the interfaces. By adjusting the geometrical parameters and saturation magnetizations, the potential profile can be dynamically tuned to control mode localization, enabling multi-channel or unidirectional spin-wave routing. These findings demonstrate that strip-loaded YIG bilayers provide an effective platform for spatial-frequency signal separation, paving the way for compact, frequency-selective magnonic logic components, demultiplexers, and energy-efficient filters.

Speaker

Martyshkin Aleksandr Aleksadnrovich
Saratov State University
Russia

Discussion

Ask question