Spin Dynamics in Open Quantum Systems: A DLvN-TDDFT Approach
Kashinath T Chavan1, Oded Hod2, Juan E Peralta1
1Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, United States.
Journal of Chemical Theory and Computation
|May 26, 2026
Summary
We developed a new computational method, driven Liouville-von Neumann (DLvN-TDDFT), to simulate electron spin transport in quantum systems. This approach reveals complex spin dynamics in magnetic nanoribbons, advancing spintronics research.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Materials science
Background:
- Modeling electron spin transport in open quantum systems is crucial for spintronics.
- Existing methods may not fully capture dynamical spin phenomena.
Purpose of the Study:
- To introduce and validate a novel computational framework for simulating spin-polarized electron transport.
- To explore spin dynamics in low-dimensional magnetic materials.
Main Methods:
- Developed a spin-uncompensated driven Liouville-von Neumann methodology.
- Integrated this into the time-dependent density functional theory (DLvN-TDDFT) framework.
- Validated the approach using benchmark simulations of molecular junctions.
Main Results:
- Applied the DLvN-TDDFT to a magnetic zigzag graphene nanoribbon junction.
- Observed rich spin-resolved current dynamics under external electric fields.
- Demonstrated the framework's capability to model complex spin behavior.
Conclusions:
- The DLvN-TDDFT framework is a powerful tool for studying dynamical spintronic phenomena.
- This methodology shows promise for investigating spin transport in low-dimensional open quantum systems.
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