Electric transport through circular graphene quantum dots: Presence of disorder
arXiv:1107.0113 · doi:10.1103/PhysRevB.84.075446
Abstract
The electronic states of an electrostatically confined cylindrical graphene quantum dot and the electric transport through this device are studied theoretically within the continuum Dirac-equation approximation and compared with numerical results obtained from a tight-binding lattice description. A spectral gap, which may originate from strain effects, additional adsorbed atoms or substrate-induced sublattice-symmetry breaking, allows for bound and scattering states. As long as the diameter of the dot is much larger than the lattice constant, the results of the continuum and the lattice model are in very good agreement. We also investigate the influence of a sloping dot-potential step, of on-site disorder along the sample edges, of uncorrelated short-range disorder potentials in the bulk, and of random magnetic-fluxes that mimic ripple-disorder. The quantum dot's spectral and transport properties depend crucially on the specific type of disorder. In general, the peaks in the density of bound states are broadened but remain sharp only in the case of edge disorder.
9 pages, 9 figures, published version
References in corpus (30)
- Energy Band Gap Engineering of Graphene Nanoribbons
- Energy Gaps in Graphene Nanoribbons
- The structure of suspended graphene sheets
- Chiral tunneling and the Klein paradox in graphene
- Substrate-induced band gap opening in epitaxial graphene
- Chaotic Dirac billiard in graphene quantum dots
- A tight-binding approach to uniaxial strain in graphene
- Quantum interference and Klein tunneling in graphene heterojunctions
- Spin qubits in graphene quantum dots
- Strong suppression of weak (anti)localization in graphene
- Evidence of Klein tunneling in graphene p-n junctions
- Transport measurements across a tunable potential barrier in graphene
- Structure, Stability, Edge States and Aromaticity of Graphene Ribbons
- Electron transport in disordered graphene
- Intervalley scattering, long-range disorder, and effective time reversal symmetry breaking in graphene
- Midgap states and charge inhomogeneities in corrugated graphene
- Conductance quantization and transport gap in disordered graphene nanoribbons
- Quantum dots in graphene
- Edge disorder induced Anderson localization and conduction gap in graphene nanoribbons
- Quantum dot behavior in graphene nanoconstrictions
- Bound states and magnetic field-induced valley splitting in gate-tunable graphene quantum dots
- Quasi-bound states of quantum dots in single and bilayer graphene
- Robustness of edge states in graphene quantum dots
- Electrostatic confinement of electrons in an integrable graphene quantum dot
- Electron-Hole Crossover in Graphene Quantum Dots
- Analytic Model for the Energy Spectrum of a Graphene Quantum Dot in a Perpendicular Magnetic Field
- Inducing energy gaps in graphene monolayer and bilayer
- Models of electron transport in single layer graphene
- Transition to Landau Levels in Graphene Quantum Dots
- Energy gap in graphene nanoribbons with structured external electric potentials
Cited by in corpus (15)
- Scattering of two-dimensional Dirac fermions on gate-defined oscillating quantum dots
- Interplay of Aharonov-Bohm and Berry phases in gate-defined graphene quantum dots
- Electron confinement in graphene with gate-defined quantum dots
- Electron dynamics in graphene with gate-defined quantum dots
- Density of states as a probe of electrostatic confinement in graphene
- Dot-bound and dispersive states in graphene quantum dot superlattices
- Disorder induced loss of magnetization in Lieb's graphene quantum dots
- Gate-defined coupled quantum dots in topological insulators
- Trapping photon-dressed Dirac electrons in a quantum dot studied by coherent two dimensional photon echo spectroscopy
- Resonant scattering of Dice quasiparticles on oscillating quantum dots
- Factorization of Dirac Equation in Two Space Dimensions
- Factorization of Dirac Equation and Graphene Quantum Dot
- Imaging the localization of the quasi-bound states in graphene antidots
- The numerical operator method to the real time dynamics of currents through the nanostructures with different topologies
- Zero-energy states in graphene quantum dot with wedge disclination