Entanglement spectrum of Su-Schrieffer-Heeger-Hubbard model

We investigate the entanglement spectrum of the ground state of the Su-Schrieffer-Heeger-Hubbard model. The topological phases of the model can be identified by degeneracy of the largest eigenvalues of entanglement spectrum. The study of the periodic boundary condition is enough to obtain the phase diagram of the model, without the consideration of the open boundary condition case. By analyzing the states corresponding to the degenerate entanglement spectrum and showing the related edge states in real space, physical interpretation about the relation between bulk-edge correspondence and the entanglement spectrum is presented. The method of the entanglement spectrum can be applicable in studying other topological phases of matter.