Intrinsic topological magnons in arrays of magnetic dipoles
arXiv:2108.08459 · doi:10.1038/s41598-022-05469-4
Abstract
We study a simple magnetic system composed of periodically modulated magnetic dipoles with an easy axis. Upon adjusting the modulation amplitude alone, chains and two-dimensional stacked chains exhibit a rich magnon spectrum where frequency gaps and magnon speeds are easily manipulable. The blend of anisotropy due to dipolar interactions between magnets and geometrical modulation induces a magnetic phase with fractional Zak number in infinite chains and end states in open one-dimensional systems. In two dimensions it gives rise to topological modes at the edges of stripes. Tuning the amplitude in two-dimensional lattices causes a band touching, which triggers the exchange of the Chern numbers of the volume bands and switches the sign of the thermal conductivity.
9 figures
References in corpus (20)
- Observation of the Magnon Hall Effect
- Theoretical prediction of rotating magnon wavepacket in ferromagnets
- Topological Magnon Insulator in Insulating Ferromagnet
- Topological Nature of the Phonon Hall Effect
- The Fascinating World of Landau-Lifshitz-Gilbert Equation: An Overview
- Topological Magnons and Edge States in Antiferromagnetic Skyrmion Crystals
- Chiral Magnonic Edge States in Ferromagnetic Skyrmion Crystals Controlled by Magnetic Fields
- Reconfigurable magnonic mode-hybridisation and spectral control in a bicomponent artificial spin ice
- Topological Magnetoelastic Excitations in Non-Collinear Antiferromagnets
- Topological bands with Chern number C=2 by dipolar exchange interactions
- Spin-orbital dynamics in a system of polar molecules
- Moiré magnons in twisted bilayer magnets with collinear order
- Manipulation of coupling and magnon transport in magnetic metal-insulator hybrid structures
- Dipolar spin waves in uniaxial easy-axis antiferromagnets: A natural topological nodal-line semimetal
- Topological Magnon Bands and Unconventional Thermal Hall Effect on the Frustrated Honeycomb and Bilayer Triangular Lattice
- Quantum field theory of topological spin dynamics
- Magnonic Su-Schrieffer-Heeger Model in Honeycomb Ferromagnets
- Robust edge states in magnetic domain-wall racetrack
- Hinge Magnons from Non-collinear Magnetic Order in Honeycomb Antiferromagnet
- Stable and unstable trajectories in a dipolar chain