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Keywords
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Filed Effect Transistor, Graphene, NEGF, Resonant Tunneling, Quantum Dot
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Abstract
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A novel functional field effect transistor (FET) is introduced. The proposed FET is modeled on graphene
nanoribbon (GNR), however it is applicable for any two dimensional structures with energy gap. As in most
graphene-based FETs, current passes through semiconducting 2D GNR. But here by the special geometry of
gate contact, the GNR is turned into two coupled quantum dots in series. By applying gate voltage, discrete
energy levels are generated in the two quantum dots of the channel and resonant tunneling transport occurs
through these levels. The coupling between Dots and sizes of Dots determine the current characteristic of
the device. By self consistently solving the NEGF and 3D Poisson equations, current of the FET is derived.
Resonant tunneling of carriers results in step-like increase of current with drain voltage and current peaks are
observed by the increment of gate voltage, i.e. negative differential conductance occurs.
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