Crystal fields, exchange, and dipolar interactions and noncollinear magnons of erbium oxide

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Maleki, Kian, Flatté, Michael E.
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915472020078592
author Maleki, Kian
Flatté, Michael E.
author_facet Maleki, Kian
Flatté, Michael E.
contents We simulate the properties of magnons in erbium oxide, a noncollinear antiferromagnet, from an effective single-ion Hamiltonian, including exchange and long-range dipolar interactions. We parametrize the crystal field splitting of Er$_2$O$_3$ using Steven's operators and obtain the effective symmetry-dependent exchange constants between different erbium ions quenched by the crystal field at different symmetry sites. We apply the Holstein-Primakoff transformation to the noncollinear spin system and employ paraunitary diagonalization for the effective spin Hamiltonian. The addition of the dipolar interaction to the exchange magnon dispersion changes the magnon bands drastically. The long-range nature of the dipolar interaction provides challenges to convergence, however we find that the averaged and normalized difference in the magnon dispersion is less than an averaged factor of $10^{-6}$ if the dipolar interaction is included out to the fortieth nearest neighbor.
format Preprint
id arxiv_https___arxiv_org_abs_2504_07234
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Crystal fields, exchange, and dipolar interactions and noncollinear magnons of erbium oxide
Maleki, Kian
Flatté, Michael E.
Mesoscale and Nanoscale Physics
Quantum Physics
We simulate the properties of magnons in erbium oxide, a noncollinear antiferromagnet, from an effective single-ion Hamiltonian, including exchange and long-range dipolar interactions. We parametrize the crystal field splitting of Er$_2$O$_3$ using Steven's operators and obtain the effective symmetry-dependent exchange constants between different erbium ions quenched by the crystal field at different symmetry sites. We apply the Holstein-Primakoff transformation to the noncollinear spin system and employ paraunitary diagonalization for the effective spin Hamiltonian. The addition of the dipolar interaction to the exchange magnon dispersion changes the magnon bands drastically. The long-range nature of the dipolar interaction provides challenges to convergence, however we find that the averaged and normalized difference in the magnon dispersion is less than an averaged factor of $10^{-6}$ if the dipolar interaction is included out to the fortieth nearest neighbor.
title Crystal fields, exchange, and dipolar interactions and noncollinear magnons of erbium oxide
topic Mesoscale and Nanoscale Physics
Quantum Physics
url https://arxiv.org/abs/2504.07234