Magneto-optical response in the arbitrary-Chern number topological phase on square lattice

• The arbitrary-Chern number topological phase is constructed on square lattice.
• The optical absorption spectra are distinct in different Chern number phases.
• The physical mechanisms are revealed for the dichroism of the absorption peaks.

In this work, we investigate the magneto-optical response in the arbitrary-Chern number topological phase. Based on the Dirac theory, we derive the analytic expressions for the magneto-optical response. More importantly, we construct the model on the possible square lattice and make the numerical calculations with the exact diagonalization method. We find the analytical and numerical results are in good agreement with each other. For the optical absorption spectrum, the low-energy absorptive peaks and the corresponding hopping processes are distinct in different Chern number phases, heavily depending on the filling factor of the system. While for the optical Hall conductivities, the physical mechanisms are revealed for the dichroism of the absorption peaks in response to the right- and left-circularly polarized light. We discuss the feasibility of these results in experiment.