Topological Magnon Frequency Combs

Abstract: Exploring the synergy between topological physics and nonlinear dynamics unveils profound insights into emergent states of matter. Inspired by recent experimental demonstrations of topological frequency combs in photonics, we theoretically introduce topological magnon frequency combs (MFCs) in a two-dimensional triangular skyrmion lattice. Computing the Chern numbers of magnon bands reveals robust chiral edge states. Strikingly, these topological MFCs originate from nonlinear four-magnon scattering among the chiral edge modes, activated by dual-frequency driving without an amplitude threshold. Comb spacings are readily tunable through excitation frequency detuning. Micromagnetic simulations validate our predictions with good concordance. This work paves the way for defect-immune magnonic devices exploiting MFCs and sparks investigations into topological-nonlinear phenomena in magnetic systems.