Berlin 2015 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 28: Transport: Topological insulators 2 (TT with HL/DS)
HL 28.1: Talk
Tuesday, March 17, 2015, 09:30–09:45, H 3005
How electron-electron interactions may lead to a spontaneous time reversal symmetry breaking in (fractional) topological insulators — •Tobias Meng1,2 and Eran Sela3 — 1Institut für Theoretische Physik, Technische Universität Dresden, 01062 Dresden, Germany — 2Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland — 3Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel Aviv, 69978, Israel
We analyze the consequences of strong electron-electron interactions in topological insulators. Naively, topological insulators can be thought of as two copies of quantum Hall states for spin up and spin down electrons at opposite magnetic field, hence maintaining time reversal symmetry. Using an extension of the coupled-wire construction of quantum Hall states to systems with zero magnetic field, we find that interactions between electrons of spin up and spin down can stabilize a large family of fractional topological phases with broken time reversal invariance. The latter is manifest by a spontaneous spin polarization, a finite Hall conductivity, or by both. This suggests the possibility that strongly correlated fractional topological insulators may be unstable to spontaneous symmetry breaking.