Saved in:
Bibliographic Details
Main Authors: Wiedmann, Raymond, Hering, Dag-Björn, Sulaiman, Vanessa, Walther, Matthias R., Schmidt, Kai P., Uhrig, Götz S.
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2511.03528
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909887901990912
author Wiedmann, Raymond
Hering, Dag-Björn
Sulaiman, Vanessa
Walther, Matthias R.
Schmidt, Kai P.
Uhrig, Götz S.
author_facet Wiedmann, Raymond
Hering, Dag-Björn
Sulaiman, Vanessa
Walther, Matthias R.
Schmidt, Kai P.
Uhrig, Götz S.
contents We investigate quantum effects on magnon excitations in a minimal spin-1/2 Heisenberg model for 2D altermagnets on the square lattice. A continuous similarity transformation is applied in momentum space to derive an effective Hamiltonian that conserves the number of magnon excitations. This allows us to quantitatively calculate the one-magnon dispersion, the effects of magnon-magnon interactions, and the dynamic structure factor in a certain range of parameters. In particular, we focus on the altermagnetic spin splitting of the magnon bands and the size of the roton minimum. We further map out divergencies of the continuous similarity transformation for different types of generators, which signal either the breakdown of the Néel-ordered phase or the presence of significant magnon decay.
format Preprint
id arxiv_https___arxiv_org_abs_2511_03528
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Quantum effects in the magnon spectrum of 2D altermagnets via continuous similarity transformations
Wiedmann, Raymond
Hering, Dag-Björn
Sulaiman, Vanessa
Walther, Matthias R.
Schmidt, Kai P.
Uhrig, Götz S.
Strongly Correlated Electrons
Quantum Physics
We investigate quantum effects on magnon excitations in a minimal spin-1/2 Heisenberg model for 2D altermagnets on the square lattice. A continuous similarity transformation is applied in momentum space to derive an effective Hamiltonian that conserves the number of magnon excitations. This allows us to quantitatively calculate the one-magnon dispersion, the effects of magnon-magnon interactions, and the dynamic structure factor in a certain range of parameters. In particular, we focus on the altermagnetic spin splitting of the magnon bands and the size of the roton minimum. We further map out divergencies of the continuous similarity transformation for different types of generators, which signal either the breakdown of the Néel-ordered phase or the presence of significant magnon decay.
title Quantum effects in the magnon spectrum of 2D altermagnets via continuous similarity transformations
topic Strongly Correlated Electrons
Quantum Physics
url https://arxiv.org/abs/2511.03528