ABSTRACT
In the early 1990s, Rolland et al. [1-4] at Bell Northern Research developed a negative chirp MachZehnder modulator (MZM) for 10 Gb/s optical communication systems that utilized the quantum con˜ned Stark eŸect (QCSE) [5,6] in the InGaAsP/InP material system. ™ey published early work on the means to generate the optimal negative chirp for maximum dispersion-limited reach over standard optical ˜ber with these InP-based MZMs [7], demonstrating >100 km of over-˜ber reach in 1993 [8]. In parallel, Sano et al. [9,10] at Hitachi published early work for an MZM design in the InGaAs/InAlAs material system.
