1.5 μm asymmetric Fabry-Perot modulators with two distinct modulation and chirp characteristics

This letter discusses the design and the realization of asymmetric Fabry-Perot modulators with InP/InGaAsP distributed Bragg reflectors and 80 AlInGaAs quantum wells. We demonstrate two types of modulators utilizing two different top reflectors: an InP to air interface and a Si/SiO2/Si coating. The first modulator showed a monotonic reduction in the reflectivity as the bias voltage increased, and achieved a 2.2 dB insertion loss and a 15 dB contrast ratio at the resonant wavelength. The second modulator showed an initial reduction and then an increase in the reflectivity as the bias changed from 0 to -10 V. The chirp calculation based on the measured data reveals that the second modulator exhibits two distinct positive and negative chirp characteristics. (C) 1998 American Institute of Physics.