Ultrafast Magnetization Induced from Raman-Active Axial Chiral Phonons
Abstract
Axial chiral phonons, which carry angular momentum and exhibit unusually large magnetic moments, provide a new degree of freedom for controlling the time-reversal symmetry and magnetic properties of quantum materials. While infrared-active axial phonons are efficiently excited to large amplitudes by circularly polarized terahertz pulses, their application may be constrained by short lifetimes, small penetration depths, low spatial resolution, and limited availability of optical sources. Here, we report that an axial Raman-active phonon mode in CeF3 exhibits a significant magnetic moment and an exceedingly long lifetime that more closely matches the paramagnetic spin dynamics. The axial phonon population is resonantly driven by a near-infrared laser pulse with rotating linear polarization, known as an optical centrifuge, a coherent control scheme never applied to solids before. The phonon-driven magnetization observed by time-resolved Faraday rotation scales quadratically with incident power and rapidly decreases at high temperatures, consistent with phonon inverse Faraday effect from many-body spin-phonon coupling. Our findings open a new avenue for using shaped laser pulses from widely accessible light sources to manipulate coherent axial chiral phonons and ultrafast spintronics.
Related
BibTeX
@misc{huang2026ultrafast,
title = {{Ultrafast Magnetization Induced from Raman-Active Axial Chiral Phonons}},
author = {Chuankun Huang and Alexander Milner and Jiaming Luo and Jianbo Ye and Gaihua Ye and Junjie Zhang and Cynthia Nnokwe and Boris I. Yakobson and Rui He and Valery Milner and Hanyu Zhu},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.14179},
eprint = {2609.14179},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.14179},
}
RIS
TY - UNPB
TI - Ultrafast Magnetization Induced from Raman-Active Axial Chiral Phonons
AU - Chuankun Huang
AU - Alexander Milner
AU - Jiaming Luo
AU - Jianbo Ye
AU - Gaihua Ye
AU - Junjie Zhang
AU - Cynthia Nnokwe
AU - Boris I. Yakobson
AU - Rui He
AU - Valery Milner
AU - Hanyu Zhu
PY - 2026
DA - 2026/09/12
PB - arXiv
DO - 10.48550/arxiv.2609.14179
UR - https://arxiv.org/abs/2609.14179
AB - Axial chiral phonons, which carry angular momentum and exhibit unusually large magnetic moments, provide a new degree of freedom for controlling the time-reversal symmetry and magnetic properties of quantum materials. While infrared-active axial phonons are efficiently excited to large amplitudes by circularly polarized terahertz pulses, their application may be constrained by short lifetimes, small penetration depths, low spatial resolution, and limited availability of optical sources. Here, we report that an axial Raman-active phonon mode in CeF3 exhibits a significant magnetic moment and an exceedingly long lifetime that more closely matches the paramagnetic spin dynamics. The axial phonon population is resonantly driven by a near-infrared laser pulse with rotating linear polarization, known as an optical centrifuge, a coherent control scheme never applied to solids before. The phonon-driven magnetization observed by time-resolved Faraday rotation scales quadratically with incident power and rapidly decreases at high temperatures, consistent with phonon inverse Faraday effect from many-body spin-phonon coupling. Our findings open a new avenue for using shaped laser pulses from widely accessible light sources to manipulate coherent axial chiral phonons and ultrafast spintronics.
ER -