Abstract: A semiconductor switching device for guiding and amplifying electromagnetic radiation is disclosed. An electrode pattern which defines a number of strip-shaped guiding members is provided on a layer structure analogous to that of a semiconductor laser. According to the invention the radiation guiding members have tapering juxtaposed ends in a transition area. Adjacent radiation guiding members in the transition area are situated within each other's amplification profile. The radiation guiding members are preferably separated from each other by insulation areas which do not extend to the common active layer. The invention may be used, for example, in switching radiation signals between two or more radiation paths in optical communication.

Abstract: A semiconductor laser or traveling wave intensifier has an active layer between two passive semiconductor layers, and a strip-shaped electrode geometry. The active layer is uniform in thickness, while at least one of the passive layers within the strip-shaped geometry comprises a strip-shaped zone which contains portions having different refractive indices n.sub.1 and n.sub.2. According to the invention it holds that(n.sub.1 -n.sub.2) (d.sub.1 -d.sub.2)>0,wherein n.sub.1 is the refractive index of the portion which at least within said strip-shaped zone adjoins the active layer, d.sub.1 is the thickness thereof within the strip-shaped zone, and d.sub.2 is the thickness thereof beside the strip-shaped zone.

Abstract: A semiconductor laser/amplifier is disclosed in which the radiation oscillates only in one longitudinal mode. According to the invention this is achieved by a strip-shaped active region which exhibits periodic variations in amplification (and preferably also in the amplification profile) in its longitudinal direction over at least a part of its length. The period of the amplification variation is at least ten times the wavelength of the radiation.