Acoustic attenuation in magnetic insulator films: effects of magnon polaron formation

A magnon and a phonon are the quanta of spin wave lattice wave, respectively, they can hybridize into polaron when their frequencies wavenumbers match close enough values at exceptional point. Guided by an analytically calculated dispersion, dynamical phase-field simulations performed to investigate effects formation on attenuation bulk acoustic in magnetic insulator film. It is shown that stronger magnon-phonon coupling leads larger attenuation. The also demonstrate existence minimum interaction time required for formation, which found decrease with magnetoelastic coefficient but increase damping coefficient. These results deepen understanding mechanisms crystals provide insights design new-concept interconnects operate based acoustically driven propagation.