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Published on: July 24, 2015
Chiral tunneling in a twisted graphene bilayer
Wen-Yu He1, Zhao-Dong Chu, Lin He
1Department of Physics, Beijing Normal University, Beijing, 100875, People's Republic of China.
Physical Review Letters
|August 27, 2013
Summary
Researchers discovered a new form of the Klein paradox in twisted graphene bilayers. This phenomenon allows for tunable chiral tunneling probabilities, offering control over electronic properties by adjusting barrier height or incident energy.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- The Klein paradox describes perfect transmission or reflection in graphene systems.
- Existing understanding involves graphene monolayer and Bernal graphene bilayer.
Purpose of the Study:
- To demonstrate a novel manifestation of the Klein paradox in twisted graphene bilayers.
- To explore the tunable chiral tunneling of quasiparticles with different chiralities.
Main Methods:
- Theoretical investigation of electron transport through potential barriers.
- Analysis of quasiparticle behavior in twisted graphene bilayers.
Main Results:
- Identified a new Klein paradox incarnation in twisted graphene bilayers.
- Demonstrated adjustable chiral tunneling probabilities (perfect to partial reflection/tunneling).
- Tunability achieved by controlling barrier height and incident energy.
Conclusions:
- The findings offer insights into chiral fermion tunneling dynamics.
- Provides a method for tuning the electronic properties of twisted graphene bilayers.
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