Effect of edge passivation on the electronic and transport properties of graphene nanogaps

We calculate from first principles the electronic and transport properties of straight graphene nanogaps whose edges are passivated with different impurities such as hydrogen or elements second row periodic table (boron, carbon, nitrogen, oxygen fluoride). also use a simple tight-binding model to elucidate reproduce main abinitio results. find that clear pattern emerges one moves boron fluoride, which can be used distinguish presence in junction. In particular, we conductance decreases tunneling decaying factor increases former latter. explain these results terms size atom its onsite energy. similar trend for current, is ohmic general. However, highly non-linear behavior negative differential resistance relatively small voltages found when simulation cell along direction perpendicular direction. Such surprising interesting explained by taking into account Fano resonances emerge due couplings side atoms at edge. These then template current experiments.