Antiferro-Chiral Phonons as Conjugate Fields to Néel Order in 𝒫𝒯-Symmetric Antiferromagnets
Abstract
Chiral phonons act as a phononic conjugate field to net magnetization, enabling phononic detection and control of ferromagnetic order. Whether an analogous phononic coupling exists for the compensated Néel order of antiferromagnets has remained open. Here we show that, in 𝒫𝒯-symmetric antiferromagnets, phonons with sublattice-staggered angular momentum can couple to the Néel vector like a conjugate field. Such coupling can be induced by the molecular Berry curvature-induced gyroscopic coupling between Raman and infrared-active phonons. The gyroscopic coupling is odd under both 𝒫 and 𝒯 while preserving their product. 𝒫𝒯 symmetry forbids the resulting normal modes to have a net phonon angular momentum (PAM) while allows counter-rotating local motion on inversion-related sublattices, which are dubbed the antiferro-chiral phonons (AFCPs). Reversing the Néel vector reverses the staggered phonon chirality and the sign of the coupling. Our results indicate AFCPs can serve as probes and control knobs of Néel order.
Related
- Symmetry-selective nonrelativistic spin splitting in antiferromagnets driven by coherent phonons
- Light-induced chiral altermagnets from conventional antiferromagnets
- Magnetically and electrically tunable nonlinear Hall effect in Tt-symmetric antiferromagnets
- Chiral Surface Phonons
- Electronic Orbital Angular Momentum Driven by Finite-Momentum Phonons: Beyond Chiral and Axial Phonons
BibTeX
@misc{das2026antiferrochiral,
title = {{Antiferro-Chiral Phonons as Conjugate Fields to Néel Order in $\mathcalP\mathcalT$-Symmetric Antiferromagnets}},
author = {Sanjib Kumar Das and Randy Yeh and Eider A. Vega Ramirez and Yafei Ren},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2605.08490},
eprint = {2605.08490},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2605.08490},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - UNPB
TI - Antiferro-Chiral Phonons as Conjugate Fields to Néel Order in 𝒫𝒯-Symmetric Antiferromagnets
AU - Sanjib Kumar Das
AU - Randy Yeh
AU - Eider A. Vega Ramirez
AU - Yafei Ren
PY - 2026
DA - 2026/10/28
PB - arXiv
DO - 10.48550/arxiv.2605.08490
UR - https://arxiv.org/abs/2605.08490
AB - Chiral phonons act as a phononic conjugate field to net magnetization, enabling phononic detection and control of ferromagnetic order. Whether an analogous phononic coupling exists for the compensated Néel order of antiferromagnets has remained open. Here we show that, in 𝒫𝒯-symmetric antiferromagnets, phonons with sublattice-staggered angular momentum can couple to the Néel vector like a conjugate field. Such coupling can be induced by the molecular Berry curvature-induced gyroscopic coupling between Raman and infrared-active phonons. The gyroscopic coupling is odd under both 𝒫 and 𝒯 while preserving their product. 𝒫𝒯 symmetry forbids the resulting normal modes to have a net phonon angular momentum (PAM) while allows counter-rotating local motion on inversion-related sublattices, which are dubbed the antiferro-chiral phonons (AFCPs). Reversing the Néel vector reverses the staggered phonon chirality and the sign of the coupling. Our results indicate AFCPs can serve as probes and control knobs of Néel order.
ER -