Spatial division of spin wave signal in a waveguide based on a ferrimagnet/antiferromagnet structure

A study on the propagation of spin waves in a waveguide based on a ferrimagnetic film of iron-yttrium garnet (YIG) with a longitudinally oriented layer of antiferromagnetic iron-rhodium (FeRh) has been conducted. The case where the transverse dimension of the FeRh layer is an order of magnitude smaller than the waveguide width is considered. By means of micromagnetic modeling, the problem of exciting surface spin waves in the antenna region and detecting the integral magnitude of the dynamic magnetization in the output section of the structure has been solved. It is shown that changing the temperature of the FeRh layer leads to a variation in the amplitude-frequency characteristics. Moreover, in the output section, there is a localization of the spin wave intensity either in the YIG region, underneath the FeRh layer, or in the free area of the film. This is caused by power division of the input signal due to the change in the magnetization of the FeRh layer. The proposed structure based on YIG/FeRh can be used as logical devices in magnonics and for spatial-frequency signal selection in magnonic networks.