arXiv:1201.6431 · Physical Review B
Topological invariants for interacting topological insulators with inversion symmetry
Zhong Wang, Xiao-Liang Qi, Shoucheng Zhang
Abstract
For interacting ${Z}_{2}$ topological insulators with inversion symmetry, we propose a simple topological invariant expressed in terms of the parity eigenvalues of the interacting Green's function at time-reversal invariant momenta and zero frequency. We derive this result from our previous formula involving the integral over the frequency-momenta space. This formula greatly simplifies the explicit calculation of ${Z}_{2}$ topological invariants in inversion-symmetric insulators with strong interactions.