Picosecond nonlinear optical response of a GaAs/AlGaAs asymmetric triple quantum well structure at room temperature

The optical nonlinearity in a GaAs/AlGaAs asymmetric triple quantum well (A TQW) structure is investigated by using pump-probe spectroscopy at room tem perature. The input power dependence of the transmission of light through t he ATQw sample shows a strong optical nonlinearity. The nonlinear behavior is due to the quantum-confined Stark effect accompanied by field-induced an ticrossing between subbands. The transmittance of the probe pulse is given by a picosecond response. The ATQW was found to provide a new scheme of qua ntum devices at room temperature.