Toward carbon based quantum electronics: Quantum transport in graphene heterojunctions

Electron transport in graphene has attracted intense research interest due to its exotic quantum transport behavior discovered in this system in the relation to the device applications beyond CMOS operation. In this presentation, we will discuss ballistic charge transport and quantum carrier collimation in graphene, both of which appear even at room temperature. In addition, we will discuss electronic transport measurements in patterned locally gated graphene nanoconstrictions with tunable transmission and bipolar heterojunctions. We observe various unusual transport phenomena, such as energy gap formation in confined graphene structures, and quantum interference of collimated electron waves which promise novel electronic device applications based on graphitic carbon nanostructures.