5. Pulse lasers

The development of pulsed lasers is driven by the need to transmit at very high data rates. There are several methods for increasing throughput: Time Division Multiplexing (TDM), which increases throughput per channel, and Wavelength Division Multiplexing (WDM), which increases the number of channels. Today, WDM is the most advantageous solution. However, TDM technology also offers possibilities for very high-speed transmission, particularly at 160 Gbit/s. For this type of application, pulse sources are required that generate pulses at very high rates and of short duration. In addition, these sources can be used for other applications such as optical sampling, analog-to-digital conversion, etc.

Several solutions exist for pulse generation in semiconductor lasers: gain switching, loss trigger switching and mode locking. Since the rate of gain switching is limited...