In this work we investigate the effects of oxidative functionalization groups on the
structure of graphene nanoribbons and also the effects of constrictions caused by the
emergence of a nanopore to the tape, where these effects were analyzed by means of electron
transport via longitudinal external field center. Our calculations were parameterized by the
semi-empirical model of the theory of extended Huckel-ETH, adopting the method of Green's
functions of non equilíbrio- NEGF. The currents were calculated through the Landauer
equation that uses the transmission function of the region spreader to the flow of electrons
with energy E coming out of the electrode. By means of this approach, it was possible to
analyze the behavior of charge carriers in each of the proposed devices, as well as the nature
of such behavior. Were found to curves I(V) two transport regimes: Ohmic and NDR,
checking maximum current and also the threshold voltage (VTh1 <VTh2 <VTh3 <VTh4) in
which occurs the regime change of transport for the nanoribbon (without oxidizing, high
oxidation and low average oxidation, respectively) located suggests that due to the presence
of two nanoconstrições in the graphene nanoribbon as regions of quantum confinement and
electronic proportional states at the functionalization. It was observed that the center pore of
the tape has created two nanoconstrições in the sides of the ribbon, thus allowing the
electronic confinement devices based on these ribbons, characterizing it as a resonant
tunneling diode DRT verified by the peak / valley ratio. We can conclude that our proposed
device is according to experimental results for nanodevices and their applicability not be
restricted on the oxidation states, being a positive factor that contributes to the
phenomenological aspects of electronic transport in graphene and fabrication of nanodevices
low cost.
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