Physics Colloquium: A topological insulator-based platform for Majorana bound states

Dr. Kristof Moors, Institute for Semiconductor Nanoelectronics, Peter Grünberg Institute 9 (PGI-9),

Abstract: Majorana bound states (MBSs) have the potential to be used as robust carriers of quantum information for future fault-tolerant quantum information processing applications. The most studied experimental platform for realizing a topological superconductor with MBSs is based on III-V semiconductor nanowires with strong spin-orbit coupling and proximity-induced superconductivity. While the realization in this system is well understood in the pristine case, disorder and imperfections can complicate the formation as well as the experimental verification. I will present two alternative MBS platforms, based on magnetic and nonmagnetic topological insulators. Because MBSs can be formed out of their topologically protected surface or edge states, these systems are expected to have a higher tolerance for imperfections. I will discuss the realization of the topological phase, the robustness against disorder, and clear and robust transport signatures of MBSs in these platforms, which we investigate with detailed tight-binding simulations. I will also comment on the latest experimental status.

BIO: Kristof Moors obtained his PhD in 2017 at the Institute for Theoretical Physics of KU Leuven University and nanoelectronics research center Imec on electron transport in nanostructures. He was a postdoctoral fellow at the Department of Physics and Materials Science of the University of Luxembourg during 2017-2019. In 2019, he joined PGI-9, where he is currently leading a modeling and simulation task force on topological material-based (hybrid) nanoelectronic devices. In close collaboration with experimental research groups on site, Kristof Moors and his team work towards the realization of topological material-based qubits and quantum computing applications. He is Principal Investigator in the European Quantera-MAGMA project on magnetic topological insulators for robust Majorana bound states, Member of Bavaria’s High-Tech Agenda Project on Quantum Computing based on Topological Materials, and Associate Member of the ML4Q (Matter and Light for Quantum Computing) Cluster of Excellence of the German Research Foundation (DFG).