Surface electronic structure of Bi2Se3 Topological Insulator

by Philip Hofmann (Department of Physics and Astronomy, Aarhus University)

Wednesday 24 Oct 2012, 12:00 → 13:00 Europe/Stockholm

Nordita seminar rm 122:026 (Nordita)

The so-called topological insulators are well-known, off-the-shelf materials, but they have a previously overlooked and profound "topological" property which forces their surfaces and edges to be metallic, in contrast to the insulating bulk. Moreover, the one-dimensional (two-dimensional) metal at the edge (surface) of a topological insulator was shown to be inherently robust against disturbances, and to possess special transport properties linked to the electron's spin, leading to many exciting predictions for new physics and potential applications. In this talk, I will also discuss recent results on the electronic structure and electron dynamics of the prototypical topological insulator Bi2Se3. In particular, I will focus on the formation of a quantum-confined two-dimensional electron gas (2DEG) in the conduction band of Bi2Se3 and the eventual splitting of the 2DEG states by a strong spin-orbit interaction. I will also discuss the strength of the electron-phonon coupling on Bi2Se3 and the influence of non-magnetic adsorbates on the surface electronic structure.