High contrast ratio asymmetric Fabry-Perot optical modulators based on GaAs/AlGaAs multiple quantum wells

A three-layer model and transmission matrix method are developed to analyze the modulation characteristics of GaAs/GaAlAs multiple quantum well asymmetric Fabry-Perot optical modulators. Two conditions of zero reflectivity for getting high contrast ratio are demonstrated and used to design normally-on and normally-off modulators. Low reflectivity of about 5% and high contrast ratio of about 10 are achieved.