Enhanced performance in serial-to-parallel data conversion via Raman-assisted time lens processing

We have demonstrated a new approach to enhance the uniformity of conversion efficiency in serial-to-parallel data conversion via time lens processing. In our approach, Raman amplification is applied to enhance four-wave mixing in a highly nonlinear fiber. By carefully selecting the pump wavelength, the Raman gain profile can be exploited to compensate the roll-off in conversion efficiency resulted from the varying phase mismatch between the linearly chirped pump and the signal. With Raman amplification, improvement of sensitivity up to 6.8 dB has been experimentally obtained. The variation of sensitivity across the output channels has been reduced from 8.4 to 2.0 dB.