Analysis and fabrication of an all-optical wavelength converter based on directionally-coupled semiconductor optical amplifiers

The operation of a novel all-optical wavelength converter based on directionally-coupled semiconductor optical amplifiers is described. Merits such as extinction enhancement and digital response are expected through a simple analytical model and a sophisticated transfer matrix method developed to take into account the spatial distributions of the optical power, carrier density, refractive index, propagation constant, and coupling coefficient along device. We fabricated devices operating at 1.55 mu m band using an InGaAsP/InP material system and demonstrated successfully the static characteristics of wavelength conversion with the expected advantages. Devices are as small as 1.5 mm and do not need any active/passive integration step during fabrication.