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Updated: Mar 19, 2026
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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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Ultrafast Magnetic Order Transition Driven by Excited-State Carrier Relaxation in Ferromagnetic Heterostructures.
Yuchong Kang1, Jian Yuan1, Shunwei Yao1
1School of Physics, Sun Yat-Sen University, Guangzhou 510275, China.
The Journal of Physical Chemistry Letters
|March 18, 2026
Summary
Researchers demonstrated ultrafast magnetic state switching in CrI3/CrBr3 heterostructures using photoexcited electrons. This discovery enables rapid, stable magnetic state generation for spintronic devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- All-optical control of magnetism is crucial for ultrafast spintronic devices.
- Generating transient magnetic states with long-term stability is a significant challenge.
Purpose of the Study:
- To propose and investigate the potential of photoexcited electron relaxation in type-II spin-antiparallel heterostructures for creating multiple stable magnetic states.
- To understand the dynamics of ultrafast magnetic phase transitions.
Main Methods:
- Photoinduced spin-dynamics simulations were performed on the CrI3/CrBr3 heterostructure.
- The influence of electron-phonon coupling (EPC) and spin-orbit coupling (SOC) on relaxation pathways and rates was analyzed.
Main Results:
- An ultrafast phase transition from antiferromagnetic (AFM) to ferrimagnetic (FiM) state was observed within 826 fs.
- The competition between EPC and SOC critically determines relaxation pathways and rates.
- Exciting electrons to higher-energy states accelerated the phase transition to 346 fs due to enhanced EPC and SOC.
Conclusions:
- The study advances the understanding of dynamic coupling between spin, charge, and lattice degrees of freedom in ultrafast magnetic order transitions.
- The findings pave the way for developing advanced nonvolatile memory and neuromorphic computing systems.
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