Intensity nonreciprocity reversal of spin wave in magnonic crystal by specific wavenumber excitation

Abstract

Abstract Spin wave propagation in a magnonic crystal excited at a specific wavenumber was investigated by micromagnetic simulation modelling with meander-shaped antennae. The dispersion relation when excited at wave number k which corresponds to the boundary of the Brillouin zone, shows a pair of strong spots that originate from the magnonic upper and lower bands. When excited at wavenumber slightly offset from k above, additional strong spots appear and it shows intensity nonreciprocity reversal. It can be interpreted in terms of the repeated or reduced zone scheme of the Brillouin zone. These characteristics have the potential for novel control of nonreciprocity.