Controlling different nonlinear dynamics by tailoring magnonic bands in permalloy microconduits
Phys. Rev. Applied 24, 024018 – Published 7 August, 2025
DOI: https://doi.org/10.1103/hmtn-pv2j
Abstract
Magnetic systems possess the unique capability to access multiple magnonic bands within a single device by tuning the spin-wave dispersion relationship. In this work, we demonstrate that distinct nonlinear magnonic processes—including three-magnon scattering, four-magnon scattering, and high-harmonic generation—can be selectively activated and controlled within a single microconduit by engineering the magnon spectrum through an externally applied bias magnetic field. Four-magnon scattering and both resonant and nonresonant excitations are observed across all bias fields, whereas three-magnon scattering only occurs at low bias fields (<40 mT) within the same structure. Notably, the efficiency of harmonic generation exhibits a significant decline as the bias field increases. Additionally, a systematic width-dependent analysis reveals that increasing the conduit width suppresses both three- and four-magnon scattering and reduces harmonic generation efficiency. Spatially resolved imaging of spin-wave dynamics is performed using microfocused Brillouin light-scattering microscopy, and the experimental results are interpreted with the support of analytical modeling. These comprehensive findings establish a platform for tuning nonlinear magnonic responses in confined geometries and offer insights that are critical to developing magnon-based information processing technologies.
