Abstract
We propose a way of current modulation in a quasi-one-dimensional (Q1D) structure composed of a gapped graphene quantum wire (QW) sandwiched between two semi-infinite armchair graphene nanoribbons (AGNRs). This current modulation stems from the valley-orbit interaction (VOI) in gapped graphene under an external electric field perpendicular to the wire. We take the confinement potential of the QW to be a parabolic one plus a quartic term, and demonstrate within the perturbation theory that the external electric field results in a difference between the wave vectors of two distinct ( and ) valley electrons in the QW, similar to that in the spin field-effect transistor (SFET) proposed by Datta and Das. Specific magnitudes of the external electric field in our case can thus also cause a current blocking effect. This result realizes significant current modulation, offering prospects of field effect device applications in valleytronics.