Micromagnetic simulations of magnon-magnon coupling in synthetic antiferromagnets with tilted magnetic anisotropy.

Abstract

Hybrid magnonics has attracted extensive attention for its potential applications in quantum information processing, especially following the discovery of strong coupling in magnon-magnon hybrid systems. In this paper, we studied the coupling phenomena between the left-handed (LH) and right-handed (RH) magnon modes in synthetic antiferromagnets with a tilted perpendicular magnetic anisotropy (PMA). By tilting the PMA at a certain angle from the film normal, we achieved strong magnon-magnon coupling without the need for an external magnetic field. The resulting hybrid eigenmodes exhibit characteristics of a linear combination of pure LH and RH modes. In addition, micromagnetic simulations revealed in detail the gradual change of hybrid resonance modes from approximately linear to elliptic, and eventually to circular polarization as the coupling strength gradually decreases. We also examined the effects of an applied magnetic field on the coupling strength and mechanism between the two eigenmodes. These findings provide valuable insights into magnetic dynamics within hybrid magnonic systems for spintronic applications involving magnon polarization.