The invention relates to a radiation-emitting semiconductor body, having a first semiconductor region of a first doping type, which has a first material composition, a second semiconductor region of a second doping type, which has a second material composition, an active region, which is located between the first semiconductor region and the second semiconductor region, and a first intermediate region, which is located between the first semiconductor region and the active region, wherein the active region includes a plurality of quantum well layers and a plurality of barrier layers, which are arranged alternatingly one above the other, the barrier layers have a third material composition, the first intermediate region includes at least one first blocking layer and at least one first intermediate layer, and the first blocking layer has a fourth material composition and the first intermediate layer has a fifth material composition. The invention also relates to a laser diode and to a light-emitting diode.

A laser structure comprising a first photonic crystal surface emitting laser (PCSEL), a second PCSEL, and a coupling region that extends between the first PCSEL and the second PCSEL along a longitudinal axis and that is electrically controllable so as to be capable of coherently coupling the first PCSEL to the second PCSEL. Each PCSEL include an active layer, a photonic crystal, and a two-dimensional periodic array distributed in an array plane parallel to the longitudinal axis within the photonic crystal where the two-dimensional periodic array is formed of regions having a refractive index that is different to the surrounding photonic crystal.

A light emitting device includes an active layer capable of producing light when current is injected thereinto, a first cladding layer and a second cladding layer that sandwich the active layer, a first electrode electrically connected to the first cladding layer, and a second electrode electrically connected to the second cladding layer. The active layer forms an optical waveguide that guides the light produced in the active layer. The optical waveguide has a window section that is provided in an end portion of the optical waveguide and has a band gap wider than the band gap of the active layer. The carrier concentration of a first layer provided between the window section and the second electrode is lower than the carrier concentration of the second cladding layer.

A semiconductor laser device capable of high output is provided. A semiconductor laser diode includes: a substrate; and a semiconductor stacked structure, which is formed on the substrate through crystal growth. The semiconductor stacked structure includes: an n-type (Al.sub.x1Ga.sub.(1-x1)).sub.0.51In.sub.0.49P cladding layer and a p-type (Al.sub.x1Ga.sub.(1-x1)).sub.0.51In.sub.0.49P cladding layer; an n-side Al.sub.x2Ga.sub.(1-x2)As guiding layer and a p-side Al.sub.x2Ga.sub.(1-x2)As guiding layer, which are sandwiched between the cladding layers; and an active layer, which is sandwiched between the guiding layers. The active layer is formed of a quantum well layer including an Al.sub.yGa.sub.(1-y)As.sub.(1-x3)P.sub.x3 layer and a barrier layer including an Al.sub.x4Ga.sub.(1-x4)As layer that are alternatively repetitively stacked for a plurality of periods.

Provided is a vertical cavity surface emitting laser diode (VCSEL). A tunnel junction with a high doping concentration is provided in the VCSEL. An n-type semiconductor layer of the tunnel junction has stress relative to the substrate, and is doped with at least one element such that the tunnel junction not only has a high doping concentration, but also the epitaxial layer can be oxidized and the oxidation rate is relatively stable during the oxidation process. Alternatively, the n-type semiconductor layer is doped with at least two elements. As a result, the oxidation process of the VCSEL can be stably performed, and the resistance of the tunnel junction with a high doping concentration is low. The tunnel junction is suitable to be arranged between two active layers of the VCSEL or between the p-type semiconductor and the n-type semiconductor layer of the VCSEL.

Visible spectrum quantum dot (QD) light emitting sources integrable with integrated silicon photonics include a plurality of epitaxially grown InP QDs within an active region. The light emitting sources include light emitting diodes (LEDs) and semiconductor lasers.

A quantum dot (QD) laser comprises a semiconductor substrate and an active region epitaxially deposited on the semi-conductor substrate. The active region includes a plurality of barrier layers and a plurality of QD layers interposed between each of the plurality of barrier layers. A net compressive strain associated with the plurality of QD layers is maintained below a maximum allowable strain to prevent formation of misfit dislocations within the active region of the QD laser.