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Abstract
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The electron-hole symmetry characteristic of graphene nanoribbons (GNRs) gives rise to the electron
(hole) tunneling through valence (conduction) band states. By employing this property we have
numerically investigated GNR field effect transistors with p
-type source and drain in the presence of a
gate voltage-inducedn-type channel using the non-equilibrium Green’s function formalism.
For long channels, the traditional FET-like I-V behavior is achieved, but at short channels, the sub
threshold current opens up an oscillatory dependence on the gate voltage with a considerable amount
of current of over 10
6
A. This is the characteristic current behavior of resonant tunneling transistors
that exhibit regions of negative differential resistance. The calculated discrete density of states in the
channel attributes this behavior to the constructed n-type channel island between p-type source and
drain with thin barriers formed by the energy gap
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