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Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Spin-filtered edge states and quantum Hall effect in graphene
Dmitry A Abanin1, Patrick A Lee, Leonid S Levitov
1Department of Physics, Massachusetts Institute of Technology, Cambridge, 02139, USA.
Physical Review Letters
|May 23, 2006
Summary
Graphene's quantum Hall effect reveals counterpropagating spin modes in electron edge states. These chiral spin currents can be controlled, offering new possibilities for spintronic devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Electron edge states in graphene exhibit the quantum Hall effect.
- These states possess both charge and spin properties.
Purpose of the Study:
- Investigate the role of spin splitting in the zeroth Landau level.
- Explore the generation and control of chiral spin current states.
Main Methods:
- Theoretical analysis of electron edge states in graphene.
- Modeling of spin splitting and spin-flip dynamics.
- Proposal for local control of spin-flip rates.
Main Results:
- Spin splitting of the zeroth Landau level creates counterpropagating modes with opposite spin polarization.
- These chiral spin modes result in diverse spin current states.
- A method for local control of spin-flip rates is proposed.
- Estimated Zeeman spin splitting, enhanced by exchange, yields a spin gap of several hundred Kelvin.
Conclusions:
- Chiral spin modes in graphene's quantum Hall regime offer tunable spin current states.
- Local control of spin-flip rates is feasible.
- The observed spin gap has implications for future spintronic applications.
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