THE Y-LASER - A MULTIFUNCTIONAL DEVICE FOR OPTICAL COMMUNICATION-SYSTEMS AND SWITCHING-NETWORKS

This paper gives a comprehensive review of the recent progress obtaine d with various operation modes of a Y-shaped all active waveguide devi ce with three optical input / output ports, the so called Y-laser. Use d as a monolithic semiconductor light source, single-mode emission wit h an extremely large cw tuning range of more than 50 nm is accessed. S ingle current step tuning spans up to 8-nm range. Several-GHz bandwidt h AM and FM response is achieved. Operation as a wavelength processing device is demonstrated with data-stream transformation from short wav elength fiber windows (around 780 nm or 1310 nm) to the long wavelengt h window (1550 nm), as well as with ultra wide range wavelength conver sion within the 1550-nm region, across +/- 20 nm (blue and red shift). Optical high-speed space switching / gating functions are verified up to 1 Gb/s, and packet switching of 5-Gb/s data streams is demonstrate d. Further features as a pulse reshaping device, as an electrically tr iggerable wavelength bistable device and as a mode locked pulse genera tor are addressed. Possible applications of this multifunctional devic e in future optical communication systems and switching networks are d iscussed.