Symmetry-Orchestrated Spin Relaxation in Bilayer CrI3: A Time-Domain ab initio Study
Yongjia Li1, Haoran Lu1, Run Long1
1College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University, Beijing 100875, People's Republic of China.
The Journal of Physical Chemistry Letters
|April 7, 2026
Summary
Magnetic symmetry in van der Waals magnets influences spin dynamics. This study reveals how symmetry affects hole relaxation and spin relaxation in bilayer CrI3, offering insights for spintronics.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Magnetic symmetry is crucial for van der Waals (vdW) magnets.
- Bilayer CrI3 is a key material for studying symmetry-tailored spin dynamics.
- The impact of magnetic space group symmetry on spin dynamics is not fully understood.
Purpose of the Study:
- To investigate how magnetic symmetry influences hole relaxation in bilayer ferromagnetic CrI3.
- To understand the role of symmetry in modulating electron-phonon scattering and interlayer coupling.
- To explore the relationship between magnetic symmetry and spin relaxation rates.
Main Methods:
- Utilized *ab initio* nonadiabatic molecular dynamics simulations.
- Analyzed the effects of magnetic symmetry on interlayer coupling and electron-phonon scattering.
- Investigated the coupling of hole relaxation to phonon modes.
Main Results:
- Magnetic symmetry alters scattering channels and phonon mode coupling for hole relaxation.
- Interlayer electronic state asymmetry, not magnetic symmetry hierarchy, governs energy relaxation rates.
- Spin relaxation accelerates as magnetic symmetry is reduced.
Conclusions:
- Magnetic symmetry plays a critical role in tailoring spin dynamics in vdW magnets.
- Understanding these relationships is vital for advancing spintronic devices.
- This research provides a framework for manipulating magnetic symmetry to control spin properties.
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