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Transient Laser-Induced Magnetic Order and Relaxation Pathways in TiCrCT2 (T = O, F) MXenes
Xueke Yu1, Qi Gao1, Bingxue Li1
1College of Physical Science and Technology, Yangzhou University, Yangzhou, Jiangsu 225009, China.
The Journal of Physical Chemistry Letters
|June 10, 2026
Summary
Surface termination in TiCrCT2 MXenes dictates ultrafast spin dynamics. This study reveals how surface chemistry controls magnetic transitions and spin relaxation, paving the way for tailored spintronic devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Quantum Chemistry
Background:
- Ultrafast spin manipulation is crucial for advanced spintronic devices.
- The role of surface termination in magnetic material spin dynamics is not well understood.
Purpose of the Study:
- To investigate the impact of surface termination on spin dynamics in TiCrCT2 MXenes.
- To elucidate the microscopic mechanisms governing spin relaxation and magnetic transitions.
Main Methods:
- Real-time time-dependent density functional theory (TD-DFT).
- Nonadiabatic molecular dynamics simulations.
- Analysis of electronic structure and electron-phonon coupling.
Main Results:
- Surface termination leads to distinct magnetic responses in TiCrCO2 and TiCrCF2.
- TiCrCF2 exhibits a ferrimagnetic-to-ferromagnetic transition due to Ti spin reversal.
- Spin-conserving charge transfer and spin-resolved band structure govern carrier relaxation dynamics.
Conclusions:
- Surface termination is a key factor in controlling ultrafast spin responses in MXenes.
- Electron-phonon coupling is more dominant than spin-orbit coupling for spin transitions.
- Findings provide a unified mechanism for magnetization dynamics and highlight surface engineering for spintronics.
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