Symmetry-selective nonrelativistic spin splitting in antiferromagnets driven by coherent phonons
Abstract
Nonrelativistic spin splitting (NRSS) in antiferromagnets (AFMs) enables magnetization-free spin polarization for ultrafast spintronics. Here, we demonstrate that coherent phonons can dynamically induce and control NRSS in collinear AFMs. Excitation of Γ-point infrared-active phonons lifts the spin degeneracy of the ground state, while the residual sublattice-connecting symmetries determine the momentum-space form of the induced splitting. Because the relevant infrared modes couple to orthogonal in-plane light polarizations, distinct spin-split phases can be selectively activated by the polarization of the driving field. Using first-principles calculations for MnPS3, we show that a mode that breaks all sublattice-connecting symmetries induces an s-wave spin-split state with Δ(Γ)≠0, whereas a symmetry-distinct mode that preserves a sublattice-connecting mirror symmetry generates a d-wave altermagnetic state with Δ(Γ)=0. In both cases, the spin splitting grows linearly with the phonon amplitude and reverses the induced spin polarization when the displacement is reversed. Our results establish coherent lattice driving as a direct, polarization- and mode-selective route to dynamically induce distinct NRSS phases in AFMs.
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BibTeX
@misc{rajpurohit2026symmetryselective,
title = {{Symmetry-selective nonrelativistic spin splitting in antiferromagnets driven by coherent phonons}},
author = {Sangeeta Rajpurohit and Mohsen Yarmohammadi and Sheikh Rubaiat Ul Haque and Tony F. Heinz and Aaron M. Lindenberg and Tadashi Ogitsu},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.01844},
eprint = {2609.01844},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.01844},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Symmetry-selective nonrelativistic spin splitting in antiferromagnets driven by coherent phonons
AU - Sangeeta Rajpurohit
AU - Mohsen Yarmohammadi
AU - Sheikh Rubaiat Ul Haque
AU - Tony F. Heinz
AU - Aaron M. Lindenberg
AU - Tadashi Ogitsu
PY - 2026
DA - 2026/09/01
PB - arXiv
DO - 10.48550/arxiv.2609.01844
UR - https://arxiv.org/abs/2609.01844
AB - Nonrelativistic spin splitting (NRSS) in antiferromagnets (AFMs) enables magnetization-free spin polarization for ultrafast spintronics. Here, we demonstrate that coherent phonons can dynamically induce and control NRSS in collinear AFMs. Excitation of Γ-point infrared-active phonons lifts the spin degeneracy of the ground state, while the residual sublattice-connecting symmetries determine the momentum-space form of the induced splitting. Because the relevant infrared modes couple to orthogonal in-plane light polarizations, distinct spin-split phases can be selectively activated by the polarization of the driving field. Using first-principles calculations for MnPS_3, we show that a mode that breaks all sublattice-connecting symmetries induces an s-wave spin-split state with Δ(Γ)≠0, whereas a symmetry-distinct mode that preserves a sublattice-connecting mirror symmetry generates a d-wave altermagnetic state with Δ(Γ)=0. In both cases, the spin splitting grows linearly with the phonon amplitude and reverses the induced spin polarization when the displacement is reversed. Our results establish coherent lattice driving as a direct, polarization- and mode-selective route to dynamically induce distinct NRSS phases in AFMs.
ER -