All-Optical Wavelength Conversion With Extinction Ratio Improvement of 100 Gb/s RZ-Signals in Ultralong Bulk Semiconductor Optical Amplifiers

All-optical wavelength conversion in ultralong semiconductor optical amplifier (UL-SOA) is presented. Opposite to other SOA based single path wavelength converters the UL-SOA's property as an extinction ratio (ER) regenerator can be used additionally to the wavelength conversion. When converting to lower wavelengths, cross-gain modulation as well as four-wave mixing (FWM) can be used as wavelength conversion mechanism. For the conversion to higher wavelengths only FWM has the ability for an ER improvement. Furthermore, the high-speed capability for the wavelength conversion with ER improvement in bulk UL-SOAs is analysed for 100 Gb/s RZ-signals. The degradation due to bit pattern effects is investigated for RZ-50% PRBS of different lengths. No significant influence could be observed for PRBS orders up to 25.