Cascadability and fanout of semiconductor optical amplifier wavelength shifter

Data at bit rates of 1 or 2 Gb/s are transferred through two cascaded, broadband wavelength shifters, which operate using gain saturation in semiconductor optical amplifiers. Such devices copy data from a modulated pump signal, in which the intensity of the marks is sufficient to significantly compress the gain of the amplifier, to a CW probe signal, producing the complement of the data. Furthermore, fanout (multicasting) is demonstrated in a single device by using two input CW probe signals. Such devices may find importance in wavelength division multiplexed systems requiring wavelength reuse and reassignment.<>