Confined dipole and exchange spin waves in a bulk chiral magnet with Dzyaloshinskii-Moriya interaction

Abstract

The Dzyaloshinskii-Moriya interaction (DMI) has an impact on excited spin waves in the chiral magnet Cu${}_2$OSeO${}_3$ by means of introducing asymmetry on their dispersion relations. The confined eigenmodes of a chiral magnet are hence no longer the conventional standing spin waves. Here we report a combined experimental and micromagnetic modeling study by broadband microwave spectroscopy we observe confined spin waves up to eleventh order in bulk Cu${}_2$OSeO${}_3$ in the field-polarized state. In micromagnetic simulations we find similarly rich spectra. They indicate the simultaneous excitation of both dipole- and exchange-dominated spin waves with wavelengths down to (47.2 $\pm$ 0.05) nm attributed to the exchange interaction modulation. Our results suggest DMI to be effective to create exchange spin waves in a bulk sample without the challenging nanofabrication and thereby to explore their scattering with noncollinear spin textures.

References in corpus (5)

• Observation of two independent skyrmion phases in a chiral magnetic material
• The quantum origins of skyrmions and half-skyrmions in Cu2OSeO3
• Magnon dispersion shift in the induced-ferromagnetic phase of the noncentrosymmetric MnSi
• Low spin wave damping in the insulating chiral magnet Cu${}_2$OSeO${}_3$
• Microwave spectroscopy of the low-temperature skyrmion state in Cu2OSeO3

Cited by in corpus (4)

• Frustration model and spin excitations in the helimagnet FeP
• Tunable gigahertz dynamics of low-temperature skyrmion lattice in a chiral magnet
• Chiral standing spin waves in skyrmion lattice
• Nonreciprocal Spin Waves in Nanoscale Domain Walls Detected by Scanning X-ray Microscopy in Perpendicular Magnetic Anisotropic Fe/Gd Multilayers