Floquet topological insulators

Such a strategy was considered in various physical contexts, ranging from irradiated materials to ultracold atoms in shaken optical lattices, but it was pioneered in photonic experiments using femtosecond-laser-written lattices.

“Such a strategy was considered in various physical contexts, ranging from irradiated materials (Oka and Aoki, 2009;Lindner, Refael, and Galitski, 2011;Cayssol et al., 2013) to ultracold atoms in shaken optical lattices (Jotzu et al., 2014;Eckardt, 2017;Fläschner et al., 2018), but it was in fact pioneered in photonic experiments using femtosecond-laser-written lattices (Rechtsman, Zeuner, Plotnik”

In the high-frequency regime, the topological classification of periodically driven systems is strictly equivalent to that of static systems.

“Consequently, in the high-frequency regime (Ω → ∞), the topological classification of periodically driven systems is strictly equivalent to that of static systems (Kitagawa, Berg et al., 2010;Lindner, Refael, and Galitski, 2011;Cayssol et al., 2013):”

The time-dependent Hamiltonian in Eq. (32) is equivalent to that describing electrons in graphene when irradiated by circularly polarized light.

“Interestingly, we note that the time-dependent Hamiltonian in Eq. ( 32) is equivalent to that describing electrons in graphene when the latter is irradiated by a circularly polarized light (Oka and Aoki, 2009;Cayssol et al., 2013);”