OPTIMAL SPECTRAL AND POWER PARAMETERS FOR ALL-OPTICAL WAVELENGTH SHIFTING - SINGLE-STAGE, FANOUT, AND CASCADABILITY

Abstract

We analyze a gain-saturated semiconductor-optical-amplifier (SOA) all-optical wavelength shifter with respect to its spectral and power characteristics as well as its capability for high fanout and cascadability. The extinction and signal-to-noise ratios, the two main figures-of-merit for a wavelength-shifted signal, are determined by accounting for gain saturation and spectral shifting which occur due to the depletion of the injected carrier density. We find that the optimal pump (i.e. original) and probe (i.e. shifted) wavelengths are red-shifted by 15 nm and blue-shifted by 20 nm, respectively, relative to the initial unsaturated SOA gain peak, with the optimal wavelength separation being..