All-optical 80-gb/s time-division demultiplexing using polarization-insensitive cross-phase modulation in photonic crystal fiber

We describe an all-optical 80-Gb/s time-division demultiplexer, which utilizes cross-phase modulation in a commercial photonic crystal fiber. Compared to back-to-back 10-Gb/s measurements, the demultiplexer achieves better than a 2.5-dB power penalty for all eight channels. More importantly, we demonstrate a novel scheme for polarization-insensitive operation, which uses only the birefringence of the fiber itself and proper alignment of the clock pulse polarization. Using this technique, the polarization sensitivity of the converted power is found to be less than 0.4 dB, allowing for error-free demultiplexing even while the data polarization state is scrambled