Realization of all-optical wavelength converter based on directionally coupled semiconductor optical amplifiers

We propose a novel all-optical wavelength converter based on directionally coupled (DC) semiconductor optical amplifiers (SOA) and simulate its characteristics using a simple model to find out such advantages as extinction enhancement and digital response. We then fabricate devices in the 1.55 μm band, and successfully demonstrate the wavelength conversion operation with the above-mentioned advantages. Very compact size and no need of active/passive integration are other significant merits of DC SOA's.