Characterizing wave functions in graphene nanodevices: electronic transport through ultrashort graphene constrictions on a boron nitride substrate

Abstract

We present electronic transport measurements through short and narrow (30x30 nm) single layer graphene constrictions on a hexagonal boron nitride substrate. While the general observation of Coulomb-blockade is compatible with earlier work, the details are not: we show that the area on which charge is localized can be significantly larger than the area of the constriction, suggesting that the localized states responsible for Coulomb-blockade leak out into the graphene bulk. The high bulk mobility of graphene on hexagonal boron nitride, however, seems not consistent with the short bulk localization length required to see Coulomb-blockade. To explain these findings, charge must instead be primarily localized along the imperfect edges of the devices and extend along the edge outside of the constriction. In order to better understand the mechanisms, we compare the experimental findings with tight-binding simulations of such constrictions with disordered edges. Finally we discuss previous experiments in the light of these new findings.

References in corpus (23)

• Electric Field Effect in Atomically Thin Carbon Films
• Energy Band Gap Engineering of Graphene Nanoribbons
• Suspended Graphene: a bridge to the Dirac point
• Graphene Nano-Ribbon Electronics
• Peculiar Width Dependence of the Electronic Property of Carbon Nanoribbons
• Phase Coherent Transport of Charges in Graphene Quantum Billiard
• Energy gaps in etched graphene nanoribbons
• Conductance quantization and transport gap in disordered graphene nanoribbons
• Edge disorder induced Anderson localization and conduction gap in graphene nanoribbons
• Coulomb blockade in graphene nanoribbons
• Quantum dot behavior in graphene nanoconstrictions
• Graphene quantum dots: Beyond a Dirac billiard
• Transport gap in side-gated graphene constrictions
• Transport in Nanoribbon Interconnects Obtained from Graphene Grown by Chemical Vapor Deposition
• Magneto-transport through graphene nano-ribbons
• Multi-mode Fabry-Pérot conductance oscillations in suspended stacking-faults-free InAs nanowires
• Cyclotron radiation and emission in graphene
• Reactive-Ion-Etched Graphene Nanoribbons on a Hexagonal Boron Nitride Substrate
• Transconductance fluctuations as a probe for interaction induced quantum Hall states in graphene
• Disorder induced Coulomb gaps in graphene constrictions with different aspect ratios
• Fabry-Perot interference, Kondo effect and Coulomb blockade in carbon nanotubes
• Electronic triple-dot transport through a bilayer graphene island with ultrasmall constrictions
• Edge state transport through disordered graphene nanoribbons in the quantum Hall regime

Cited by in corpus (5)

• Electrostatically confined monolayer graphene quantum dots with orbital and valley splittings
• Quantum Interference in Graphene Nanoconstrictions
• From diffusive to ballistic transport in etched graphene constrictions and nanoribbons
• Graphene nanoribbons: relevance of etching process
• Measuring the local quantum capacitance of graphene using a strongly coupled graphene nanoribbon