All-optical ultrafast differentiation and integration for femtosecond pulse shaping based on programmable differential group delay

Abstract

We propose and demonstrate a novel scheme of multi-functional all-optical ultrafast signal processor for femtosecond pulse shaping based on programmable differential group delay (DGD), which is capable of performing both all-optical differentiation and integration simultaneously, and can easily switch two functionalities by simply tuning the orientation of a polarizer. The differentiation waveforms and integration windows length can be adjusted by programming the DGD time. Utilizing numerical simulation we obtain the differential pulses and their autocorrelation of ~400-fs Gaussian signal for DGD of 0.5 ps and 4 ps, while achieve its integral pulses and their autocorrelation for DGD of 0.5 ps, 1.5 ps, and 3.5 ps. We further experimentally demonstrate the all-optical differentiation and all-optical integration of ~400-fs Gaussian signals whose results agree well with the theoretical prediction and simulation result. Using autocorrelation method, we observe in detail the differential and integral processing of femtosecond pulses at various DGD for the first time according to our knowledge. Our scheme can work over the whole communication band with variable operation wavelength, and is competitive in ultrafast pulse shaping for quantum control due to highly reconfigurable and flexible features.