Electronic transport in graphene-topological insulator hybrid devices
Graphene and topological insulators are both materials where electronic transport properties are dictated by relativistic energy-momentum dispersion relations. Several topological insulators, such as Bi2Se3, have a layered structure, with weak out-of-plane van-der-Waals bonds, allowing for easy exfoliation into thin flakes. In the talk I will describe a new fabrication technique where layered materials such as graphene and Bi2Se3 can be vertically stacked, creating a new kind of heterostructure. In electronic devices fabricated from such heterostructures, each material is contacted individually, and electronic properties of the interface are measured at low tempertures. The measurements reveal that the interface is a tunnel junction of exceptionally good quality. I will show how some of the basic properties of both materials can be probed through mutual spectroscopy using this tunnel junction.