Magnon-magnon interaction induced by nonlinear spin wave dynamics

TL;DR

This paper demonstrates how nonlinear spin-wave dynamics can induce effective interactions between magnon modes, leading to spectral splitting and parametric instabilities in yttrium iron garnet, with implications for quantum and classical computation.

Contribution

It provides the first experimental and theoretical evidence of nonlinear magnon-magnon interactions induced by spin wave dynamics in a yttrium iron garnet disk.

Findings

Spectral splitting observed with increasing drive amplitude.

Theoretical model based on magnon three-wave mixing Hamiltonian explains the phenomena.

Identification of parametric Suhl instabilities at high power.

Abstract

We experimentally and theoretically demonstrate that nonlinear spin-wave dynamics can induce an effective resonant interaction between non-resonant magnon modes in a yttrium iron garnet disk. Under strong pumping near the ferromagnetic resonance mode, we observe a spectral splitting that emerges with increasing drive amplitude. This phenomenon is well captured by a theoretical framework based on the linearization of a magnon three-wave mixing Hamiltonian, which at high power leads to parametric Suhl instabilities. The access and control of nonlinear magnon-parametric processes enables the development of experimental platforms in an unexplored parameter regime for both classical and quantum computation protocols.