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Localization of dirac electrons in rotated graphene bilayers
G Trambly de Laissardière1, D Mayou, L Magaud
1Laboratoire de Physique Theorique et Modelisation, Universite de Cergy-Pontoise-CNRS, F-95302 Cergy-Pontoise Cedex, France. guy.trambly@u-cergy.fr
Nano Letters
|February 4, 2010
Summary
Localized Dirac electron wave functions in rotated graphene bilayers are achievable via Moire patterns, overcoming Klein paradox challenges for graphene devices. This effect is strongest with minimal rotation angles.
Area of Science:
- Condensed matter physics
- Materials science
- Quantum mechanics
Background:
- The Klein paradox poses challenges for confining Dirac electrons using electrostatic potentials.
- Graphene-based devices could benefit from effective electron confinement strategies.
Purpose of the Study:
- To investigate the localization of Dirac electron wave functions in rotated graphene bilayers.
- To explore the role of Moire patterns in achieving this localization.
Main Methods:
- Combined ab initio and tight-binding computational approaches.
- Analysis of wave function behavior in bilayer graphene with varying rotation angles.
Main Results:
- Demonstrated that Moire patterns in rotated graphene bilayers can localize Dirac electron wave functions.
- Observed that wave function localization is maximized at small rotation angles between layers.
Conclusions:
- Moire patterns offer a viable mechanism for confining Dirac electrons in graphene bilayers, addressing Klein paradox limitations.
- The degree of layer rotation angle is critical for optimizing wave function localization in such systems.
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