All-optical Mach-Zehnder interferometer wavelength converters and switches with integrated data- and control-signal separation scheme

All-optical Mach-Zehnder interferometer (MZI) wavelength converters and switches with monolithically integrated data- and control-signal separation schemes are reported. Two schemes to separate the data from the strong control signals are discussed. A first dual-order mode configuration uses modes of different symmetry for the data and control signals. A second configuration uses additional MZIs to separate the two signals. The control-signal separation permits to operate the devices with copropagating data and control signal without distortion of the control signal in the data-signal output. Copropagative operation allows for shorter switching windows compared to the counterpropagative operation. Further, this concept enables cascading of several devices since the control signal is filtered out and does not disturb the signal processing in a next cascade of devices. The all-optical switches are characterized under static and dynamic 10 GHz conditions.