Pico-second non-linear optical transmission in an asymmetric triple quantum well structure

The transmission of a GaAs/AlGaAs asymmetric triple quantum well structure shows strong nonlinear behavior as a function of the incident laser intensity. The nonlinear behavior is attributed to the Stark shift due to the triple resonance of three electronic states in the conduction band, which is induced by the optical excitation. The pump and probe measurement shows that the build up of internal field in the quantum wells is achieved within a few pico-seconds after the excitation.