Optical frequency switching with SSG-DBR structured devices

Broad-range tunable wavelength semiconductor lasers are developed by introducing super structure grating (SSG) distributed Bragg reflector (DBR) structures into laser cavities. The lasing wavelength of the lasers can be varied over a wavelength range wider than 100 nm. Very fast wavelength switching over a broad range is demonstrated using the lasers. The lasing wavelength can be set to 16 different channels with 0.8 nm (100 GHz) spacing, and can switch among these channels very quickly. High speed channel distribution of signals to different output ports in accordance with these wavelengths is demonstrated by introducing an arrayed-waveguide grating demultiplexer into the system. Broad-range tunable (90 nm) wavelength conversion of high-bit-rate signals (10 Gbit/s) is also demonstrated using SSG-DBR lasers. Clear eye opening is observed in the converted signal. In the full tunable wavelength range, the bit error rate of the converted signal is almost the same as that of the input signal. This indicates that waveform degradation does not occur in the conversion. Repeated wavelength conversion is demonstrated by introducing transmitted input signal light component to another wavelength converter. These results indicate that the tunable laser wavelength converter holds promise for various applications.