The results of the high-speed response of GaAs/AlGaAs multiple quantum well (MQW) based asymmetric Fabry Perot (ASFP) reflection modulator are presented. The measured 3 dB electrical frequency response bandwidth of the modulator was 600 MHz. The contrast ratio of the modulator was 8.9 dB for a driving voltage of 13 V, at an operating wavelength of 862 nm.
Electric field induced changes in the excitonic band-edge absorption spectra of Multiple-Quantum-Well (MQW) structures were investigated theoretically and experimentally. A comparison was made of three different exactly solvable methods for calculating quantum-well energies. The small effects due to conduction-band nonparabolicity and valence-band mixing were included. Transmission spectra were recorded for an In .12 Ga .88 As-GaAs optical waveguide modulator structure. The theoretical model was used to predict the changes in the long-wavelength tail of the band-edge absorption for different electric fields.
Field-induced refractive index variations in GaAs/AlGaAs multiple quantum well waveguide modulator