Reconfigurable Optical Intensity Differentiator Utilizing DGD Element

A reconfigurable optical intensity differentiation with tunable bandwidth is experimentally demonstrated using differential-group-delay (DGD) element. By adjusting the polarization launch into DGD or turning off one of the two channels, a pair of polarity-reversed differentiations and the absolute value of the differential signal are obtained. Results show that the low average errors for all cases are <;0.1. In addition, we achieve 10-GHz pulse train with the amplitude fluctuation of ~0.4-dB from a low frequency optical clock signal.