Graphene is one atomic layer of carbon atoms arranged in a honeycomb lattice. It is the thinnest, strongest material known, which is also chemically inert, flexible, transparent and an excellent conductor of electricity and heat. Probably the most important benefit of graphene’s discovery is the attention it has brought to many other two-dimensional (2D) layered materials. Using similar strategies to those applied to graphene one can extract single atomic layers from other bulk crystals. For example, graphene’s ‘sister’ material hexagonal boron nitride has similar mechanical properties but on the contrary is an insulator.
In the last couple of years, a novel field has emerged which deals with structures and devices assembled layer-by-layer from various atomically-thin crystals. These new multilayer structures have proved to be extremely versatile, showing exceptional electronic and optical properties, new physics and new functionality. In particular, we have overcome the band gap problem by producing tunnelling transistors of two layers of graphene separated by a few atoms thick layer of molybdenum disulphide.
In this talk I will review recent progress in this field and present important milestones in its development. Specific attention will be paid to fabrication of such structures and their chemical stability as well as charge transport experiments demonstrating various proof-of-concept functionalities.