Photonic generation of ultrawideband doublet pulse based on cross-absorption modulation in an electroabsorption modulator

We propose and demonstrate a new approach to generate optical ultrawideband (UWB) doublet pulse by using cross-absorption modulation (XAM) in an electroabsorption modulator (EAM). when launching continuous-wave (CW) probe light and signal pulse into an electroabsorption modulator to take part in cross-absorption modulation, the probe light is modulated by the signal pulse and the polarity is reversed. The combination of the output probe light and the time delayed signal pulse with proper power control can produce UWB doublet pulse. The UWB doublet pulse generated in the experiment with the center frequency, 10-dB bandwidth, and the fractional bandwidth conforms to the FCC UWB definition.