Interaction induced topological phase transition in Bernevig-Hughes-Zhang model

We study interaction induced topological phase transition in Bernevig-Hughes-Zhang model. Topological nature of the phase transition is revealed by directly calculating the Z2 index of the interacting system from the single-particle Green's function. The interacting Z2 index is also consistently checked through the edge spectra. Combined with ab initio methods, present approach is a useful tool searching for correlated topological insulating materials from the first-principle point of view.