1.5 MU-M ASYMMETRIC FABRY-PEROT MODULATORS WITH 2 DISTINCT MODULATIONAND CHIRP CHARACTERISTICS

This letter discusses the design and the realization of asymmetric Fab ry-Perot modulators with InP/InGaAsP distributed Bragg reflectors and 80 AlInGaAs quantum wells. We demonstrate two types of modulators util izing two different top reflectors: an InP to air interface and a Si/S iO2/Si coating. The first modulator showed a monotonic reduction in th e reflectivity as the bias voltage increased, and achieved a 2.2 dB in sertion loss and a 15 dB contrast ratio at the resonant wavelength. Th e second modulator showed an initial reduction and then an increase in the reflectivity as the bias changed from 0 to -10 V. The chirp calcu lation based on the measured data reveals that the second modulator ex hibits two distinct positive and negative chirp characteristics. (C) 1 998 American Institute of Physics.