Detecting Topological Phases in Cold Atoms

Xiong-Jun Liu, K. T. Law, T. K. Ng, Patrick A. Lee

Published 2013-06-21, updated 2013-09-01Version 2

Chern insulators are band insulators which exhibit a gap in the bulk and gapless excitations in the edge. Detection of Chern insulators is a serious challenge in cold atoms since the Hall transport measurements are technically unrealistic for neutral atoms. By establishing a natural correspondence between the time-reversal invariant topological insulator and quantum anomalous Hall system, we show for a class of Chern insulators that the topology can be determined by only measuring Bloch eigenstates at highly symmetric points of the Brillouin zone (BZ). Furthermore, we introduce two experimental schemes including the spin-resolved Bloch oscillation to carry out the measurement. These schemes are highly feasible under realistic experimental conditions. Our results may provide a powerful tool to detect topological phases in cold atoms.