Correlation effects in topological insulators

Datum

06.09.2017

Zeit

14:00 - 15:00

Sprecher

Prof. Dr. Björn Trauzettel

Zugehörigkeit

Institute of Theoretical Physics and Astrophysics, University of Wuerzburg

Sprache

en

Hauptthema

Materialien

Andere Themen

Materialien, Physik

Host

Christine Malbrich

Beschreibung

Abstract Topological insulators are a class of materials that are insulating in the bulk but conduct at their surface. We are particularly interested in the surface states of topological insulators which are protected by time-reversal symmetry. These surface states are helical because their spin degree of freedom and their direction of motion are strongly coupled. In this presentation, I want to discuss the influence of Coulomb interaction on topological insulators and their surface states. As far as transport is concerned, the interplay of Coulomb interaction and a spatial variation of spin-orbit interaction can give rise to backscattering of helical surface states. This effect may already happen for weakly interacting systems. In the presence of strong correlations, however, more intriguing phenomena can emerge. We have, for instance, recently discovered the formation of a fractional Wigner crystal [1] and a discontinuous topological phase transition that is solely driven by interactions [2]. [1] N. Traverso Ziani, F. Crepin, and B. Trauzettel, Phys. Rev. Lett. 115, 206402 (2015) [2] A. Amaricci, J. C. Budich, C. Capone, B. Trauzettel, and G. Sangiovanni, Phys. Rev. Lett. 114, 185701 (2015); Phys. Rev. B 93, 235112 (2016)

Links

• Seminars at the IFW

Letztmalig verändert: 06.09.2017, 10:03:30