Momentum-space theory for topological magnons in 2D ferromagnetic skyrmion lattices
arXiv:2405.00192 · doi:10.1103/PhysRevB.110.184409
Abstract
Magnon dynamics in skyrmion lattices have garnered significant interest due to their potential applications in topological magnonics. Existing theories often follow a single-momentum approach, assuming significant Dzyaloshinskii-Moriya Interaction (DMI) to minimize the skyrmion's dimensions, which can lead to oversimplification in describing magnon behavior. This study introduces a multi-momentum operator theory for magnons in large 2D skyrmions, where each skyrmion encompasses several thousand spins. The proposed theory fully transforms the magnon Hamiltonian into momentum space, incorporating off-diagonal terms to capture umklapp scattering caused by the skyrmion wave vectors. Our results reveal deviations from single-momentum theories, demonstrating that flat bands are not universal features of the skyrmionic magnon spectrum. Additionally, we find that manipulating the skyrmion size with an external magnetic field induces multiple topological phase transitions. At high magnetic fields, the low-energy magnon spectrum becomes densely packed and entirely topological, resembling a topological band continuum.
Supplementary notes are available with the published version (PhysRevB.110.184409)
References in corpus (18)
- Skyrmion Lattice in Two-Dimensional Chiral Magnet
- Magnetic Two-Dimensional Chromium Trihalides: A Theoretical Perspective
- Dirac magnons in honeycomb ferromagnets
- Topological Magnons and Edge States in Antiferromagnetic Skyrmion Crystals
- Properties and dynamics of meron topological spin textures in the two-dimensional magnet CrCl3
- Electrically switchable Rashba-type Dzyaloshinskii-Moriya interaction and skyrmion in two-dimensional magnetoelectric multiferroics
- Chiral Magnonic Edge States in Ferromagnetic Skyrmion Crystals Controlled by Magnetic Fields
- Topological magnon insulator spin excitations in the two-dimensional ferromagnet CrBr
- Topological magnon band structure of emergent Landau levels in a skyrmion lattice
- Topological Phases in Magnonics
- Moiré magnons in twisted bilayer magnets with collinear order
- Topological Thermal Hall Effect of Magnons in Magnetic Skyrmion Lattice
- Quantum fluctuations in the order parameter of quantum skyrmion crystals
- Quantum topological phase transitions in skyrmion crystals
- Magnetoelectric Cavity Magnonics in Skyrmion Crystals
- Insights on magnon topology and valley-polarization in 2D bilayer quantum magnets
- Designing layered 2D skyrmion lattices in moiré magnetic hetero-structures
- Magnon topological transition in skyrmion crystal