Frequency dependent harmonic distortion in a multiple-quantum-well electroabsorption modulator

Abstract
The frequency dependence of the harmonic distortion in a multiple quantum-well electroabsorption waveguide modulator is demonstrated for the first time. Low-frequency measurements agree with calculation of the harmonic distortion based upon the static nonlinear relationship between the intensity and the applied voltage. However, observed harmonic distortion at RF frequencies is significantly larger than the observed harmonic distortion due to low-frequency modulation. The frequency dependence of the harmonic indicates that a mechanism other than the nonlinear intensity-voltage relationship dominates at high frequency.