Coherent transport in graphene nanoconstrictions
- 14 November 2006
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review B
- Vol. 74 (19), 195417
- https://doi.org/10.1103/physrevb.74.195417
Abstract
We study the effect of a structural nanoconstriction on the coherent transport properties of otherwise ideal zigzag-edged infinitely long graphene ribbons. The electronic structure is calculated with the standard one-orbital tight-binding model and the linear conductance is obtained using the Landauer formula. We find that, since the zero-bias current is carried in the bulk of the ribbon, this is very robust with respect to a variety of constriction geometries and edge defects. In contrast, the curve of zero-bias conductance versus gate voltage departs from the staircase of the ideal case as soon as a single atom is removed from the sample. We also find that wedge-shaped constrictions can present nonconducting states fully localized in the constriction close to the Fermi energy. The interest of these localized states in regards to the formation of quantum dots in graphene is discussed.
Keywords
This publication has 36 references indexed in Scilit:
- Confined states and direction-dependent transmission in graphene quantum wellsPhysical Review B, 2006
- Erratum: Conductance quantization in mesoscopic graphene [Phys. Rev. B73, 195411 (2006)]Physical Review B, 2006
- Electronic Confinement and Coherence in Patterned Epitaxial GrapheneScience, 2006
- Peculiar width dependence of the electronic properties of carbon nanoribbonsPhysical Review B, 2006
- Quantum Spin Hall Effect in GraphenePhysical Review Letters, 2005
- Coulomb interactions and ferromagnetism in pure and doped graphenePhysical Review B, 2005
- Ballistic carbon nanotube field-effect transistorsNature, 2003
- Electronic transport properties of nanographite ribbon junctionsPhysical Review B, 2001
- Unconventional Quasiparticle Lifetime in GraphitePhysical Review Letters, 1996
- Condensed-Matter Simulation of a Three-Dimensional AnomalyPhysical Review Letters, 1984