A TUNABLE FEMTOSECOND MODE-LOCKED SEMICONDUCTOR-LASER FOR APPLICATIONS IN OTDM-SYSTEMS

In this paper we describe the properties of an external cavity modeloc ked semiconductor laser with a tunability of wavelength, pulse width a nd repetition rare. This modelocked laser generates optical pulses wit h pulse widths down to 180 fs and with repetition rates up to 14 GHz i n a 120 nm wavelength range near 1.55 mu m or 1.3 mu m. The generated pulses are close to the transform limit and are therefore suitable for very high speed communication systems. In addition to the tunability, this pulse source is a compact and mechanically stable device. We rep ort on two applications of this pulse source in optical time division multiplexing experiments. In the first example the modelocked laser is used as an all-optical clock recovery. In the second example the mode locked laser was used to characterize an interferometric switch by pum p-probe experiments.