Self-modulation instability in high power ferromagnetic resonance of BiYIG nanodisks
Abstract
We study the high power ferromagnetic resonance (FMR) of perpendicularly magnetized BiYIG nanodisks where the uniaxial anisotropy almost compensates the shape anisotropy. We observe a strong saturation of the averaged magnetization upon moderately increasing the amplitude of the rf field and a broadening of the FMR line towards lower and higher magnetic field. Full micromagnetic simulations reveal that a self-modulation of the dynamic magnetization is responsible of this behavior. To get more insight into this unstable dynamics, it is analysed in terms of normal modes. The number of modes involved is found to rapidly increase above the critical threshold. Still, a normal modes model taking into account only a few of them and their mutual nonlinear couplings allows us to qualitatively reproduce the observed phenomenon. The normal modes analysis and micromagnetic simulations also predict a Suhl-like instability at larger excitation power when it is slowly increased from low values, and bistability. Using two-tone spectroscopy, we directly measure the self-modulation spectrum and provide experimental evidence of bistable dynamics. These findings open some perspectives of using high dimensional dynamics in magnetic nanostructures for unconventional information processing.
Keywords
Cite
@article{arxiv.2503.07159,
title = {Self-modulation instability in high power ferromagnetic resonance of BiYIG nanodisks},
author = {Igor Ngouagnia Yemeli and Salvatore Perna and Diane Gouéré and Amel Kolli and Soraya Sangiao and José María de Teresa and Manuel Muñoz and Abdelmadjid Anane and Massimiliano d'Aquino and Hugo Merbouche and Claudio Serpico and Grégoire de Loubens},
journal= {arXiv preprint arXiv:2503.07159},
year = {2025}
}