Interaction-induced criticality in Z(2) topological insulators.
We study interaction effects in topological insulators with strong spin-orbit coupling. We find that the interplay of nontrivial topology and Coulomb repulsion induces a novel critical state on the surface of a three-dimensional topological insulator. Remarkably, this interaction-induced criticality, characterized by a universal value of conductivity, emerges without any adjustable parameters. Further, we predict a direct quantum-spin-Hall transition in two dimensions that occurs via a similar critical state.
Ostrovsky
P M
PM
Institut für Nanotechnologie, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany.
Gornyi
I V
IV
Mirlin
A D
AD