Topic: "Topological Insulators and Topological Band Theory" (Video)
ABSTRACT: A topological insulator is a material that is an insulator on its interior, but has special conducting states on its surface. These surface states are unlike any other known two dimensional conductor. They are characterized by a unique Dirac type dispersion relation and are protected by a topological property of material's underlying electronic band structure. Topological insulators have attracted considerable interest as a fundamentally new electronic phase with applications from spintronics to quantum computing. In this talk we will outline the theoretical discovery of this phase and describe experiments that have observed its signatures in both two and three dimensional electronic systems. We will close by arguing that the proximity effect between an ordinary superconductor and a topological insulator leads to a novel interface state that may provide a new venue for observing a Majorana fermion and for realizing proposals for topological quantum computation.