Momentum-dependent precessional and nutational spin pumping in a honeycomb antiferromagnet
Abstract
The ultrafast magnetic inertial dynamics on subpicosecond timescales generate an additional high-frequency terahertz nutational resonance. Here, we investigate momentum-resolved spin pumping in a two-dimensional honeycomb antiferromagnet by incorporating spin inertia into the Landau-Lifshitz-Gilbert equation. Using a microscopic two-sublattice model with J1-J2-J3 exchange interactions, we calculate the precessional and nutational magnon spectra and their corresponding intra- and inter-sublattice spin pumping contributions throughout the Brillouin zone. For parameters representative of MnPS3, we find a pronounced complementary momentum dependence of the two spin pumping channels: the precessional current is strongly suppressed around the Γ point (0.01%) and increases towards the Brillouin zone boundary (100% at K and 87% at M), whereas the nutational current is largest near Γ (100%) and decreases towards the boundary (68% at K and 69% at M). This contrasting momentum dependence provides a means of distinguishing spin nutation from conventional precessional motion. We further demonstrate that the nutational spin pumping current is strongly controlled by the inertial relaxation time η, in contrast to the comparatively weak η dependence of the precessional current. In the small-η regime, our analytical results show that the intra-sublattice nutational spin pumping current exhibits a leading-order dependence of 1/η3. The spin pumping response can also be tuned through the exchange interaction strengths and magnetic moment. Our further results on the magnetic field dependence of spin pumping reveal that the ratio of nutational spin pumping current increases with magnetic field strength, whereas the corresponding precessional counterpart decreases.
Related
- Thermodynamic origin of the phonon Hall effect in a honeycomb antiferromagnet
- Precessional modes of phonon angular momentum
- Odd-parity magnon spin polarization from chiral four-spin exchange in a honeycomb antiferromagnet
- Triplon thermal Hall response in a honeycomb-lattice J1-J2 Heisenberg antiferromagnet with Dzyaloshinskii--Moriya interactions
- Flat-band ferrimagnetism in the edge-centered honeycomb antiferromagnet: From harmonic flat magnon to broad continuum
BibTeX
@misc{mukherjee2026momentumdependent,
title = {{Momentum-dependent precessional and nutational spin pumping in a honeycomb antiferromagnet}},
author = {Suman Mukherjee and Subhadip Ghosh and Ritwik Mondal},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.19289},
eprint = {2609.19289},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.19289},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Momentum-dependent precessional and nutational spin pumping in a honeycomb antiferromagnet
AU - Suman Mukherjee
AU - Subhadip Ghosh
AU - Ritwik Mondal
PY - 2026
DA - 2026/09/16
PB - arXiv
DO - 10.48550/arxiv.2609.19289
UR - https://arxiv.org/abs/2609.19289
AB - The ultrafast magnetic inertial dynamics on subpicosecond timescales generate an additional high-frequency terahertz nutational resonance. Here, we investigate momentum-resolved spin pumping in a two-dimensional honeycomb antiferromagnet by incorporating spin inertia into the Landau-Lifshitz-Gilbert equation. Using a microscopic two-sublattice model with J_1-J_2-J_3 exchange interactions, we calculate the precessional and nutational magnon spectra and their corresponding intra- and inter-sublattice spin pumping contributions throughout the Brillouin zone. For parameters representative of MnPS_3, we find a pronounced complementary momentum dependence of the two spin pumping channels: the precessional current is strongly suppressed around the Γ point (0.01%) and increases towards the Brillouin zone boundary (100% at K and 87% at M), whereas the nutational current is largest near Γ (100%) and decreases towards the boundary (68% at K and 69% at M). This contrasting momentum dependence provides a means of distinguishing spin nutation from conventional precessional motion. We further demonstrate that the nutational spin pumping current is strongly controlled by the inertial relaxation time η, in contrast to the comparatively weak η dependence of the precessional current. In the small-η regime, our analytical results show that the intra-sublattice nutational spin pumping current exhibits a leading-order dependence of 1/η^3. The spin pumping response can also be tuned through the exchange interaction strengths and magnetic moment. Our further results on the magnetic field dependence of spin pumping reveal that the ratio of nutational spin pumping current increases with magnetic field strength, whereas the corresponding precessional counterpart decreases.
ER -