Light-induced topological phases in thin films of magnetically doped topological insulators

We study the photon-dressed electronic band structure of topological insulator thin films doped by magnetic impurities in response to an off-resonance time-periodic electromagnetic field. The irradiated a circularly polarized light undergo phase transitions, and fascinating feature distinct phases emerges diagram depending on frequency, intensity, polarization light. As particular case, quantum anomalous Hall is induced purely light-induced mass term with no need for any external field or even magnetization arising from doping impurities. Moreover, pseudo-spin (QPHI) diagram, leading anisotropic helical edge states zero total Chern number. verify these achievements numerical calculations nanoribbon film which mode behavior observed at several points diagram. emergence mentioned modes are further confirmed both calculating conductivity means Kubo formula number each band. effect parameters Landau-level fan presence perpendicular indicates various occurring higher numbers.