Modeling of schottky and ohmic contacts between metal and graphene nanoribbons using extended hückel theory (EHT)-based NEGF method

The extended huckel theory (EHT)-based NEGF method is applied to perform atomistic quantum transport simulation of Schottky and ohmic metal-GNR contacts with different metal electrodes. Effects induced by changing the GNR orientation or the number of graphene layers are discussed. The interface dipole due to the polarization of chemical bond is found to have a significant impact on the contact behavior.

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