Graphene nanoribbon devices and quantum heterojunction devices

We fabricate lithographically patterned graphene nanoribbon structures. The sizes of these energy gaps estimated from the conductance in the nonlinear response regime indicate that the gap is scaling inversely proportional to the width of the ribbons. The temperature dependent conductance measurements suggest the substantial amount of edge disorders in the graphene nanoribbons. We also fabricate the lateral graphene heterojunction devices employing the local top gate structures. Quantum conductance oscillations are observed in these devices.