Optically induced absorption modulation in a periodically δ-doped InGaAs/GaAs multiple quantum well structure

Strong optically induced absorption modulation has been achieved in a periodically δ-doped InGaAs/GaAs multiple quantum well structure. The use of δ-doping has enabled efficient modulation in short-period structures using a low-power semiconductor laser. With an excitation intensity of 100 mW/cm2 we have measured an absolute quantum well absorption change of more than 9000 cm−1 corresponding to a differential absorption change as high as 58% at the excitonic resonance.