Subpicosecond transmission change in semiconductor–embedded photonic crystal slab: Toward ultrafast optical switching

We have measured the subpicosecond photoinduced transmission change of the photonic crystal slab, in which inorganic–organic layered perovskite semiconductor is embedded for large optical nonlinearity. It is observed that sharp transmission dips shift to the blue during the irradiation of the pump pulse. This result is explained in terms of the change of the polariton dispersion relation due to the excitonic optical Stark effect. Possible application for ultrafast optical switching is discussed.