We analyze generalizations of two-dimensional topological insulators which can be realized in interacting, time reversal invariant electron systems. These states, which we call fractional topological insulators, contain excitations with fractional charge and statistics in addition to protected edge modes. In the case of sz conserving toy models, we show that a system is a fractional topological insulator if and only if σsH/e* is odd, where σsH is the spin-Hall conductance in units of e/2π, and e* is the elementary charge in units of e.
ASJC Scopus subject areas
- Physics and Astronomy (all)