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Updated: May 5, 2026

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
A model for ballistic transport across locally gated graphene bipolar junctions
Nhung T T Nguyen1, D Quang To, V Lien Nguyen
1Theoretical and Computational Physics Department, Institute of Physics, VAST, 10 Dao Tan, Ba Dinh Distr., Hanoi 10000, Vietnam.
Abstract:
An alternative model of Gaussian-type potential is suggested, which allows us to describe the transport properties of the locally gated graphene bipolar junctions in all possible charge density regimes, including a smooth transition between the regimes. Using this model we systematically study the transmission probability, the resistances, the current-voltage characteristics, and the shot noise for ballistic graphene bipolar junctions of different top gate lengths under largely varying gate voltages. Obtained results on the one hand show multifarious manifestations of the Klein tunneling and the interference effects, and on the other hand describe well typical experimental data on the junction resistances.
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