Magnons in Metallic Altermagnetic KV2Se2O
Abstract
We investigate the spin excitation in altermagnetic vanadium oxyselenides, focusing on the metallic quasi-two-dimensional compound KV2Se2O. Using a fermionic Hamiltonian derived from ab initio calculations, we compute the transverse spin susceptibilities within the random phase approximation and extract the magnon dispersion relation. We show that the altermagnetic symmetry leads to characteristic degeneracies and directional splittings in both the electronic bands and the magnon spectra along high-symmetry paths of the Brillouin zone. The metallic KV2Se2O exhibits finite magnon linewidths arising from the coupling to the particle-hole continuum. Furthermore, by fixing the magnitude of the wave vector and varying its in-plane direction, we uncover a pronounced angular dependence of the magnon energies and lifetimes, with complementary damping behavior between the two magnon branches. Upon including spin-orbit coupling, the system exhibits an out-of-plane easy c-axis anisotropy, which opens a magnon gap of approximately 6 meV at the Γ-point, possibly rendering the magnetic order stable at room temperature. Our results demonstrate that altermagnetism controls not only the dispersion but also the anisotropic decay of spin excitations, highlighting altermagnetic metals as promising platforms for directionally selective magnon transport.
Related
- Altermagnetic Magnons in Dipolar Nanomagnet Arrays
- Spacetime Dynamics of Altermagnetic Magnons
- Exchange-Driven Chiral Magnons and Weyl States in Room-Temperature Metallic XCoB2 (X= Ta, Zr and Hf) Altermagnets
- Acoustically driven magnons in CrSBr bilayers
- Observation of dark magnons in a van der Waals antiferromagnet/ferromagnet interface
BibTeX
@misc{santos2026magnons,
title = {{Magnons in Metallic Altermagnetic $\textKV_2\textSe_2\textO$}},
author = {Daniel Lourenço R. Santos and António T. Costa},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.01853},
eprint = {2609.01853},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.01853},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Magnons in Metallic Altermagnetic KV_2Se_2O
AU - Daniel Lourenço R. Santos
AU - António T. Costa
PY - 2026
DA - 2026/09/01
PB - arXiv
DO - 10.48550/arxiv.2609.01853
UR - https://arxiv.org/abs/2609.01853
AB - We investigate the spin excitation in altermagnetic vanadium oxyselenides, focusing on the metallic quasi-two-dimensional compound KV_2Se_2O. Using a fermionic Hamiltonian derived from ab initio calculations, we compute the transverse spin susceptibilities within the random phase approximation and extract the magnon dispersion relation. We show that the altermagnetic symmetry leads to characteristic degeneracies and directional splittings in both the electronic bands and the magnon spectra along high-symmetry paths of the Brillouin zone. The metallic KV_2Se_2O exhibits finite magnon linewidths arising from the coupling to the particle-hole continuum. Furthermore, by fixing the magnitude of the wave vector and varying its in-plane direction, we uncover a pronounced angular dependence of the magnon energies and lifetimes, with complementary damping behavior between the two magnon branches. Upon including spin-orbit coupling, the system exhibits an out-of-plane easy c-axis anisotropy, which opens a magnon gap of approximately 6 meV at the Γ-point, possibly rendering the magnetic order stable at room temperature. Our results demonstrate that altermagnetism controls not only the dispersion but also the anisotropic decay of spin excitations, highlighting altermagnetic metals as promising platforms for directionally selective magnon transport.
ER -