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Landau-Zener transitions with spin flipping in chiral structures
Bo-Chen Zhou1, Ran-Bo Yang1, Chun-Yu Cai1
1Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, Department of Physics, School of Science, Tianjin University, Tianjin 300354, China.
The Journal of Chemical Physics
|May 22, 2025
Summary
Chirality-induced spin selectivity arises from electron spin coupling with molecular vibrations. Spin flipping rates depend on molecular handedness and phonon properties, crucial for electron transfer in chiral systems.
Area of Science:
- Physical Chemistry
- Materials Science
- Molecular Physics
Background:
- Chirality-induced spin selectivity (CISS) is a phenomenon where chiral molecules can separate electron spins.
- Understanding the mechanisms behind CISS is vital for developing spintronic devices and understanding biological processes.
Purpose of the Study:
- To investigate Landau-Zener transitions and electron spin flipping in donor-chiral bridge-acceptor systems.
- To elucidate the role of electron-phonon coupling and molecular handedness in CISS.
Main Methods:
- Calculation of transition rates near conical intersections of potential energy surfaces.
- Analysis of electron spin coupling with the strain tensor induced by anisotropic phonon fields.
Main Results:
- Spin flipping rates are highly sensitive to the handedness of chiral bridge molecules.
- Increasing phonon wave vectors significantly enhance spin flipping rates.
- Demonstrated the critical role of electron-phonon coupling in spin selectivity.
Conclusions:
- The study reveals microscopic mechanisms governing CISS in chiral structures.
- Highlights the importance of spin selectivity in electron transfer for chemical and biological systems.
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