Triple-q Order in Na2Co2TeO6 from Proximity to Hidden-SU(2)-Symmetric Point

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

Abstract

In extended Heisenberg-Kitaev-Gamma-type spin models, hidden-SU(2)-symmetric points are isolated points in parameter space that can be mapped to pure Heisenberg models via nontrivial duality transformations. Such points generically feature quantum degeneracy between conventional single-q and exotic multi-q states. We argue that recent single-crystal inelastic neutron scattering data place the honeycomb magnet Na2Co2TeO6 in proximity to such a hidden-SU(2)-symmetric point. The low-temperature order is identified as a triple-q state arising from the Néel antiferromagnet with staggered magnetization in the out-of-plane direction via a 4-sublattice duality transformation. This state naturally explains various distinctive features of the magnetic excitation spectrum, including its surprisingly high symmetry and the dispersive low-energy and flat high-energy bands. Our result demonstrates the importance of bond-dependent exchange interactions in cobaltates, and illustrates the intriguing magnetic behavior resulting from them.

Details

Original languageEnglish
Article number146702
Number of pages8
JournalPhysical review letters
Volume131(2023)
Issue number14
Publication statusPublished - 5 Oct 2023
Peer-reviewedYes

External IDs

Scopus 85175084346

Keywords