Quantum Transport and Field Induced Insulating States in Bilayer Graphene pnp Junctions
arXiv:1009.4669 · doi:10.1021/nl101901g
Abstract
We perform transport measurements in high quality bilayer graphene pnp junctions with suspended top gates. At a magnetic field B=0, we demonstrate band gap opening by an applied perpendicular electric field, with an On/Off ratio up to 20,000 at 260mK. Within the band gap, the conductance decreases exponentially by 3 orders of magnitude with increasing electric field, and can be accounted for by variable range hopping with a gate-tunable density of states, effective mass, and localization length. At large B, we observe quantum Hall conductance with fractional values, which arise from equilibration of edge states between differentially-doped regions, and the presence of an insulating state at filling factor ν=0. Our work underscores the importance of bilayer graphene for both fundamental interest and technological applications.
4 figures, to appear in Nano Lett. Minor typos corrected
References in corpus (22)
- The electronic properties of graphene
- Chiral tunneling and the Klein paradox in graphene
- Biased bilayer graphene: semiconductor with a gap tunable by electric field effect
- Unconventional quantum Hall effect and Berry's phase of 2pi in bilayer graphene
- Gate-induced insulating state in bilayer graphene devices
- Asymmetry gap in the electronic band structure of bilayer graphene
- Graphene field-effect-transistors with high on/off current ratio and large transport band gap at room temperature
- Quantum interference and Klein tunneling in graphene heterojunctions
- Selective transmission of Dirac electrons and ballistic magnetoresistance of \textit{n-p} junctions in graphene
- Evidence of Klein tunneling in graphene p-n junctions
- Transport measurements across a tunable potential barrier in graphene
- Electronic transport and quantum Hall effect in bipolar graphene p-n-p junction
- Midgap states and charge inhomogeneities in corrugated graphene
- Quantized Transport in Graphene p-n Junctions in Magnetic Field
- Spatially resolved spectroscopy of monolayer graphene on SiO2
- Conductance of p-n-p graphene structures with 'air-bridge' top gates
- Midgap states in corrugated graphene: Ab-initio calculations and effective field theory
- Tunable Excitons in Biased Bilayer Graphene
- Electrical observation of a tunable band gap in bilayer graphene nanoribbons at room temperature
- Zero-energy states in corrugated bilayer graphene
- Probing Charging and Localization in the Quantum Hall Regime by Graphene pnp Junctions
- Flavor Symmetry and Competing Orders in Bilayer Graphene
Cited by in corpus (20)
- The electronic properties of bilayer graphene
- Electronic properties of graphene-based bilayer systems
- Anomalous sequence of quantum Hall liquids revealing tunable Lifshitz transition in bilayer graphene
- Transport spectroscopy of ultraclean tunable band gaps in bilayer graphene
- Visualization and Control of Single Electron Charging in Bilayer Graphene Quantum Dots
- Semiclassical magnetotransport in graphene n-p junctions
- Bound state energy of a Coulomb impurity in gapped bilayer graphene: "Hydrogen atom with a Mexican hat"
- Conductance of bilayer graphene in the presence of a magnetic field: Effects of disorder
- Quantum Hall Effects in Monolayer-Bilayer Graphene Planar Junctions
- Energy gaps and layer polarization of integer and fractional quantum Hall states in bilayer graphene
- Graphene: Kinks, Superlattices, Landau levels, and Magnetotransport
- Spatially resolving unconventional interface Landau quantization in a graphene monolayer-bilayer planar junction
- Quantum transport in double-gated graphene devices
- Equilibration of Quantum hall edges in symmetry broken bilayer graphene
- Unipolar transport in bilayer graphene controlled by multiple p-n interfaces
- Equilibration of quantum hall edge states and its conductance fluctuations in graphene p-n junctions
- Comparison of microscopic models for disorder in bilayer graphene: Implications for the density of states and the optical conductivity
- One-dimensional plasmons confined in bilayer graphene p-n junctions
- Mode-selective cloaking and phase-matching cavity resonances in bilayer graphene transport
- Electric field control of spins in bilayer graphene: Local moment formation and local moment interactions