Topological insulators and 3D Dirac/Weyl semimetals: A novel electronic state of matter

The electronic properties of graphene have opened up a new window in condensed matter physics research and device applications. The surface states of several materials such as B1-xSbx, Bi2Se3, Sb2Te3 and Bi2Te3 have striking similarities with graphene. In these materials, known as topological insulators, the bulk has a full insulating energy gap, whereas the surface possesses gapless highly conducting states. As a result, the electrical conduction is dominated by the surface. Following the discovery of topological insulators, another new class of materials, 3D Dirac semimetal, which is 3D analog of graphene has been reported recently. In this seminar, I present some of our recent works on electronic transport properties of topological insulators and 3D Dirac semimetals.