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Updated: Oct 31, 2025

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Gate potential-controlled current switching in graphene Y-junctions
F R V Araújo1,2, D R da Costa2, F N Lima1
1Instituto Federal do Piauí-Campus São Raimundo Nonato, 64670-000, São Raimundo Nonato, PI, Brazil.
Abstract:
In this work we investigate the ballistic transport of electrons through three-terminal graphene-based devices. The system consists of a Y-shaped junction formed by three armchair-edged graphene nanoribbons with a rectangular gate potential applied to one of the output branches, whereby current control can be established by the controlling of the refractive index in graphene p-n junctions. Transport properties are obtained by using the Landauer-Büttiker formalism and the tight-binding model within the nearest-neighbor approximation, which allows the calculation of the conductance as function of the Fermi energy, the applied potential, and the system size, as well as the current density. The results demonstrate that the applied electric field can tune the current transmission between the input and two output leads and, consequently, the proposed system acts as a current switch.
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