Topological insulators and their proximity effects with superconducting and magnetic materials

In condensed matter physics, major breakthroughs are realized with the discoveries of new states of matter. Recently, an entirely new state of matter has been predicted and observed in the so-called 2D and 3D topological insulators (TI) which are isolating in their interior but have metallic conducting surfaces with unique properties that are unknown in any other material. Beside their huge fundamental interest, these materials are considered very important in e.g. spintronics technology and quantum computing. In this project, we aim to gain deeper insight in selected research issues in this new emerging field. We will investigate how the topological surface states emerge and survive in the only known elemental topological insulator: strained alpha-Sn (alpha-Sn is also known as "white tin" as opposed to the more stable "gray tin" phase). We will also study how a topological insulator behaves when it is brought in close contact with magnetic or superconducting materials. We will characterize the properties of the superconducting state (i.e. a state in which electrical current can flow without any resistance due to the formation of electron pairs) that can be induced in the TI material by contact with a conventional superconducting material and that is believed to be quite exotic in itself. Finally, we will introduce magnetism in topological insulators by magnetic doping and investigate the interaction between a topological insulator and a magnetic material.