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Updated: Jun 25, 2025
09:06
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Optical-Helicity-Dependent Orbital and Spin Dynamics in Two-Dimensional Ferromagnets.
Shuo Li1, Ran Wang1, Thomas Frauenheim1,2
1Institute for Advanced Study, Chengdu University, Chengdu 610106, China.
The Journal of Physical Chemistry Letters
|May 29, 2024
Summary
Investigating ultrafast magnetism in 2D ferromagnets, this study reveals how circularly polarized light controls orbital angular momentum (OAM) and spin angular momentum (SAM) dynamics on attosecond timescales.
Area of Science:
- Condensed Matter Physics
- Ultrafast Magnetism
- 2D Materials
Background:
- Ultrafast spin dynamics in 2D ferromagnets are challenging to analyze.
- Disentangling orbital angular momentum (OAM) and spin angular momentum (SAM) is crucial.
Purpose of the Study:
- To investigate the OAM and SAM dynamics in Fe3GeTe2 (FGT) induced by circularly polarized light.
- To understand ultrafast spin dynamics on subfemtosecond timescales.
Main Methods:
- Employed a non-collinear spin version of real-time time-dependent density functional theory (RT-TDDFT).
- Studied dynamics induced by circularly polarized lasers.
Main Results:
- Demagnetization of the Fe sublattice in FGT shows helicity-dependent OAM and SAM precession.
- OAM and SAM precession occur faster than demagnetization (within femtoseconds).
- Circularly polarized lasers induce a periodic transverse linear response of OAM and SAM on attosecond timescales (~600 attoseconds).
Conclusions:
- Orbital and spin angular momenta dynamics can be controlled on attosecond timescales.
- Suggests a new route for manipulating angular momentum in 2D ferromagnets.
- Enables coherent control of helicity-dependent dynamics.
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