Electro-optic effects in GaAsAlGaAs multiple quantum well structures

A theoretical model for the electro-optic effects in GaAsAlGaAs multiple quantum well structures is presented. Electron and hole properties are modeled within a Transfer Matrix Technique which includes the non-parabolocity of the energy bands, and reproduces adequately the onset of quasi-bound states resulting from the influence of the electric field on QW's with finite barrier height. The method is also flexible enough to account for space charge effects in non-uniform potentials. The index of refraction has been calculated for both TE and TM modes in single and double QW structures as a function of electric fields up to 100kV/cm. Our data show noticeable polarization effects in the optical constants which increases with electric fields. In addition, the index of refraction exhibits oscillatory electro-optic effect which is due to a modulation by the electric field, of the overlap between quantized electron and hole states.