Potentially Inexpensive 10-Gb/s Tunable Dispersion Compensator with Low Polarization Sensitivity

We previously reported a simple 10-Gb/s Mach-Zehnder-interferometer-type tunable dispersion compensator (TDC) that requires only one control voltage. However, we used an expensive polarization-diversity scheme to achieve polarization independence. Here, we take advantage of the device symmetry and use a single half-wave plate to achieve low polarization sensitivity directly, saving significant cost. We demonstrate 200-km transmission with only 7-dB path penalty, with significant room for improvement.