Quantum interference of electrons through electric-field-induced edge states in stacked graphene nanoribbons

In this work, we investigate, by means of numerical simulations, the quantum interference of electrons in stacked graphene structures consisting of two unequal width, armchair-edged graphene nanoribbons. Electronic states residing near the edges of the system are induced when an external electric field is applied normal to the ribbons. By reversing the direction of electric field in the central region, one can create an electronic analogue of the optical Fabry-Perot (FP) interferometer. Electronic junctions formed at the boundaries between the central region and the left and right ones in the former play the role of the partially reflected mirrors in the latter. The observed conductance oscillations demonstrate that electrons in the edge states transporting through the system experience quantum interference similar to that of light waves passing through an optical FP interferometer. Moreover, electronic states formed at the junctions enhance inter-edge scattering which affects electron transmission significantly. The possibility to control electron transport via electric gates is also considered.