Topological quantum phase transitions in a spin-orbit coupled electron system with staggered magnetic fluxes

We investigate the topological properties of a spin-orbit coupled electron system in the presence of staggered magnetic fluxes. A series of topological quantum phase transitions occurs by tuning the magnetic fluxes, and some topological phases with high Chern numbers and high spin Chern numbers are present. We also find that in a certain region of parameters, the system becomes a hybrid topological insulator, where quantum spin Hall and quantum anomalous Hall phases coexist. We further demonstrate that the topological characterization based on the Chern number and the spin Chern number fully agrees with the characteristic spectrum of the edge states in different regimes.Copyright (c) EPLA, 2014