Title :
Modulation characteristics of semiconductor Mach-Zehnder optical modulators
Author :
Lawetz, Chris ; Cartledge, John C. ; Rolland, C. ; Yu, J.
Author_Institution :
Dept. of Electr. & Comput. Eng., Queen´´s Univ., Kingston, Ont., Canada
fDate :
4/1/1997 12:00:00 AM
Abstract :
The transmission and chirp characteristics are described for two types of semiconductor Mach-Zehnder modulators, distinguished by the differential phase shift between the two arms of the interferometer in the unbiased state. The conventional modulator has a differential phase shift of 0 radians, while the π-shift modulator has a differential phase shift of π radians. The nonlinear dependence on the applied voltage of the attenuation and phase constants of the optical signal propagating in the p-i-n waveguide leads to different characteristics for the two modulators. The influence of the splitting ratio of the Y-junctions is considered for single-arm and dual-arm (push-pull) modulation formats. The π-shift modulator is shown to yield better transmission performance for 10 Gb/s systems compared to the conventional modulator
Keywords :
electro-optical modulation; integrated optics; optical communication equipment; optical waveguides; semiconductor quantum wells; π radians; π-shift modulator; 10 Gbit/s; applied voltage; attenuation constants; chirp characteristics; differential phase shift; dual-arm push-pull modulation formats; electro optical modulation; interferometer arms; modulation characteristics; nonlinear dependence; optical signal propagation; phase constants; semiconductor Mach-Zehnder modulators; semiconductor Mach-Zehnder optical modulators; semiconductor quantum well modulators; single-arm modulation formats; transmission performance; unbiased state; Arm; Chirp modulation; Nonlinear optics; Optical attenuators; Optical interferometry; Optical modulation; Optical waveguides; Phase modulation; Phase shifting interferometry; Voltage;
Journal_Title :
Lightwave Technology, Journal of
