Abstract: An apparatus is configured to operate in a single fundamental transverse mode and the apparatus includes a waveguide layer between an n-doped cladding layer and a p-doped cladding layer. The waveguide layer includes a first waveguide part, and an active layer located between the first waveguide part and the p-doped cladding layer, the active layer being asymmetrically within the waveguide layer closer to the p-doped cladding layer than the n-doped cladding layer. The refractive index of the n-doped cladding layer being equal to or larger than the p-doped cladding layer. A first end of the first waveguide part is adjacent to the n-doped cladding layer. A second end of the first waveguide part is adjacent to a first end of the active layer. A desired donor density is doped in the first waveguide part for controlling the carrier density dependent internal optical loss in the first waveguide part at high injection levels.

Abstract: An apparatus is configured to operate in a single fundamental transverse mode and the apparatus includes a waveguide layer between an n-doped cladding layer and a p-doped cladding layer. The waveguide layer includes a first waveguide part, and an active layer located between the first waveguide part and the p-doped cladding layer, the active layer being asymmetrically within the waveguide layer closer to the p-doped cladding layer than the n-doped cladding layer. The refractive index of the n-doped cladding layer being equal to or larger than the p-doped cladding layer. A first end of the first waveguide part is adjacent to the n-doped cladding layer. A second end of the first waveguide part is adjacent to a first end of the active layer. A desired donor density is doped in the first waveguide part for controlling the carrier density dependent internal optical loss in the first waveguide part at high injection levels.

Abstract: A single pulse semiconductor laser operating in the gain-switching regime comprises a plane asymmetric waveguide and an active layer in the waveguide, the ratio of a thickness of the active layer to an optical confinement factor of the laser being extremely large, larger than about 5 ?m, for example.

Abstract: A vertical cavity surface emitting laser (VCSEL) configured to operate in a gain switching regime includes a cavity that is terminated by reflectors at both ends for enabling a standing wave of optical radiation therebetween. The cavity comprises at least one quantum well, each of the quantum wells located at a position where a value of a standing wave factor for each quantum well is between zero and one, 0<?<1.

Abstract: A vertical cavity surface emitting laser (VCSEL) configured to operate in a gain switching regime includes a cavity that is terminated by reflectors at both ends for enabling a standing wave of optical radiation therebetween. The cavity comprises at least one quantum well, each of the quantum wells located at a position where a value of a standing wave factor for each quantum well is between zero and one, 0<?<1.

Abstract: A single pulse semiconductor laser operating in the gain-switching regime comprises a plane asymmetric waveguide and an active layer in the waveguide, the ratio of a thickness of the active layer to an optical confinement factor of the laser being extremely large, larger than about 51 ?m, for example.