Special Seminar: Enrico Rossi

Date: 
Sun, 16/06/2019 - 12:00 to 13:30

"Van der Waals heterostructures with spin-orbit coupling" Van der Waals (vdW) systems offer an unprecedented freedom to combine materials with different electronic properties. Such freedom allows the creation of novel heterostructures with unique and tunable effects. In this talk I will discuss the properties of vdW systems in which one of the layers has strong spin-orbit coupling. I will consider in detail two exemplary vdW systems in this class: heterostructures formed by graphene and a topological insulator (TI), and heterostructures formed by graphene and monolayer niobium diselenide (NbSe2). I will present results for the electronic structure of these systems, and in particular its dependence on the twist angle between the two layers. I will discuss the transport properties of graphene-TI systems and show that even in the graphene layer a strong coupling between spin and charge transport is present. For graphene-NbSe2 systems I will show how the superconducting gap induced into the graphene layer, and its robustness with respect to in-plane fields, depend on the twist angle. Another very interesting class of heterostructures with spin-orbit coupling are semiconductor-superconductor Majorana nanowires. If time will allow it I will briefly discuss our recent results on the effects of gates and disorder on the electronic properties of these systems.