Tunable dispersion equalizer with a divided thin-film heater for 40-Gb/s RZ transmissions

We have developed tunable dispersion equalizers with a chirped fiber grating on the divided thin-film heater. The divided thin-film heater took an important role in the control of dispersion and dispersion slope. We successfully demonstrated the dispersion control from -304 to -196 ps/nm, the dispersion slope control from +100 to -300 ps/nm/sup 2/, and good performance in 40-Gb/s return-to-zero transmission by using this tunable dispersion equalizer.