A Two-dimension Dispersion Waveshaper Scheme with Hyperfine Bandwidth Management

Traditional wavelength selective switch (WSS) or waveshaper (WS) commonly utilizes diffraction grating as dispersive element to realize GHz-level bandwidth management. However, the gratings with highly dense grooves have a harsh condition for processing, particular in the infrared region. This study proposes a two-dimension (2D) dispersion WS which combines a virtually imaged phased array (VIPA) and a grating as disperser. Compared to the single grating configuration with the same groove density, the 2D configuration in this design has a dispersion over 9 times larger than the former at experiment. Owing to the hyperfine spectral resolution of 2D dispersion and the specially designed holograms loaded on Liquid Crystal on Silicon (LCoS), the 100MHz-level bandwidth management and flexible waveform shaping are achieved. We also experimentally demonstrate the signal filtering and switching of 2D WS in intensity-modulation direct-detection (IM/DD) optical communication systems. Additionally, the Quadrature Phase Shift Keying (QPSK) and 16 Quadrature Amplitude Modulation (16QAM) signals with different wavelengths, modulated rates and optical signal-to-noise ratios (OSNRs) operated at this WS, and the results of coherent detection show a high quality. It indicates that the hyperfine bandwidth management and flexible waveform shaping of 2D dispersion WS has the potential application in all-optical network (AON) to improve the spectral utilization efficiency and used for the complex information exchange at networks.