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Spin conductances and magnetization production in chiral molecular junctions
Richard Korytár1, Jan M van Ruitenbeek2, Ferdinand Evers3
1Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 12116 Praha 2, Czech Republic.
The Journal of Chemical Physics
|September 5, 2024
Summary
Chirality induced spin selectivity in helical molecules is investigated. Researchers predict spin accumulation at contacts, offering a new method to measure spin conductance by quantifying spin accumulation instead of spin current.
Area of Science:
- Condensed Matter Physics
- Molecular Electronics
- Spintronics
Background:
- Experimental observations show chirality-induced spin selectivity (CISS).
- Understanding spin transport in helical molecules is crucial for spintronics applications.
Purpose of the Study:
- To analytically calculate charge and spin conductances in helical molecules.
- To investigate spin-momentum locking effects and spin current behavior.
Main Methods:
- A minimal theoretical model is developed.
- Analytical calculations of charge and spin conductances are performed.
- Spin-orbit interaction is considered within the molecule.
Main Results:
- Four helical modes with spin-momentum locking are identified, analogous to quantum spin Hall edge states.
- Spin currents in leads have equal magnitude but opposite signs.
- Spin accumulation is predicted in the contact region.
Conclusions:
- Transport through helical molecules leads to spin accumulation.
- Spin conductance can be measured via spin accumulation, bypassing difficult spin current measurements.
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