Quantum Transport in Twisted Van Der Waals Heterostructures

Van der Waals materials resemble a layered deck of cards: they are made of individual sheets which are weakly bonded to their neighbors. In this last decade it was discovered that these individual sheets can be peeled off to produce a one-atom thick material. This highly surprising discovery was first made with graphite to isolate single atomic layers called graphene. Since then this technique has been applied to a range of materials to isolate new forms of 2-dimensional layered crystals. When isolated in this way, it has been found that the thin layered sheets take on new properties which can be useful for a wide range of electronics applications. At the forefront of this research is the creation of van der Waals heterostructures, which are made by combining thin layers from different materials to create entirely new structures with novel functionality. This research project explores how the properties of the combined structure can be altered by "twisting" the structure, i.e. by changing the rotational alignment between adjacently stacked layers. Twisting one layer with respect to another can drastically affect the coupling between the two layers, resulting in widely different electronic properties for the combined structure. In this way the properties of the new electronic material can be tuned for different purposes such as for the study of exotic quantum phenomena or to obtain novel quantum nanodevices with new electronic and optical properties. This project will be accomplished as part of a broadly integrated program aimed at building a collaborative and open scientific community, mentoring the next generation of scientists, and communicating physics to industry leaders and the general public.