Electron-hole asymmetry in two-terminal graphene devices

Abstract

A theoretical model is proposed to describe asymmetric gate-voltage dependence of conductance and noise in two-terminal ballistic graphene devices. The model is analyzed independently within the self-consistent Hartree and Thomas-Fermi approximations. Our results justify the prominent role of metal contacts in recent experiments with suspended graphene flakes. The contact-induced electrostatic potentials in graphene demonstrate a power-law decay with the exponent varying from -1 to -0.5. Within our model we explain electron-hole asymmetry and strong Fabri-Perot oscillations of the conductance and noise at positive doping, which were observed in many experiments with submicrometer samples. Limitations of the Thomas-Fermi approximation in a vicinity of the Dirac point are discussed.

7 pages, 8 figures

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Cited by in corpus (8)

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• Quantum behavior of graphene transistors near the scaling limit
• Charge transport through graphene junctions with wetting metal leads
• Localizing fractional quasiparticles on graphene quantum hall antidots
• Interaction-induced enhancement of $g$-factor in graphene
• Relativistic nature of carriers: Origin of electron-hole conduction asymmetry in m o n o l a ye r gr a p h e n e
• Signatures of evanescent transport in ballistic suspended graphene superconductor junctions
• Charge carrier transport asymmetry in monolayer graphene