Ultrafast all-optical wavelength conversion using nonlinear polarization rotation in a semiconductor optical amplifier

We demonstrate wavelength conversion based on nonlinear polarization rotation driven by ultrafast carrier relaxation in an InGaAsP-InGaAs multi-quantum-well (MQW) semiconductor optical amplifier (SOA). A continuous wave probe beam at a center wavelength of 1555 nm, and a control pulse of duration of 120 fs (FWHM) at a center wavelength of 1520 nm were used. We have presented wavelength conversion for different injection currents and for different control pulse energies. The conversion efficiency of 12 dB was obtained for the control pulse energies of 10 pJ.