A light-emitting thyristor includes a first semiconductor layer of a first conductivity type; a second semiconductor layer of a second conductivity type arranged adjacent to the first semiconductor layer; a third semiconductor layer of the first conductivity type arranged adjacent to the second semiconductor layer; and a fourth semiconductor layer of the second conductivity type arranged adjacent to the third semiconductor layer. The first semiconductor layer includes an active layer adjacent to the second semiconductor layer, the second semiconductor layer includes a first layer adjacent to the active layer and a second layer arranged between the first layer and the third semiconductor layer, and the first layer has a band gap wider than a band gap of the active layer and a band gap of the second layer.

The present disclosure relates to a device that includes, in order, an emitter layer, a quantum well, and a base layer, where the emitter layer has a first bandgap, the base layer has a second bandgap, and the first bandgap is different than the second bandgap by an absolute difference greater than or equal to 25 meV.

A light source includes a p-type semiconductor layer, an n-type semiconductor layer, and an active region between the p-type semiconductor layer and the n-type semiconductor layer and configured to emit light. The active region includes a plurality of barrier layers and one or more quantum well layers. The plurality of barrier layers of the active region includes at least one n-doped barrier layer that includes an n-type dopant. The active region is characterized by a lateral linear dimension equal to or less than about 10 m. The n-type dopant includes, for example, silicon, selenium, or tellurium.

Disclosed are a quantum light source and an optical communication apparatus including the same. The quantum light source device includes a vertical reflection layer disposed on a substrate, a lower electrode layer disposed on the vertical reflection layer, a horizontal reflection layer disposed on the lower electrode layer, a quantum light source disposed in the horizontal reflection layer, and an upper electrode layer disposed on the horizontal reflection layer.

A semiconductor body main include a III-V compound semiconductor material having a p-conductive region doped with a p-dopant. The p-conductive region may include at least one first section, one second section, and one third section. The second section may be arranged between the first and third sections. The second section may directly adjoin the first and third sections. An indium concentration of at least one of the sections differs from an indium concentration of the other two sections.

A pyrromethene boron complex represented by the general formula (1) is described that satisfies at least one of conditions (A) and (B) as defined. The pyrromethene boron complex is used in a color conversion composition, and a color conversion film is used in a light source unit, a display, an illumination apparatus, and a light-emitting device, where in the general

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formula (1), X is CR.sup.7 or N; and R.sup.1 to R.sup.9 are as defined.

A semiconductor device is provided. The semiconductor device includes a first semiconductor layer; a second semiconductor layer on the first semiconductor layer; an active region between the second semiconductor layer and the first semiconductor layer; an electron blocking structure between the active region and the second semiconductor layer; a first In-containing layer between the active region and the electron blocking structure; and a second In-containing layer between the electron blocking structure and the second semiconductor layer; wherein the first In-containing layer and the second In-containing layer each includes indium, aluminum and gallium, the first In-containing layer has a first aluminum content, the second In-containing layer has a second aluminum content, and the second aluminum content is less than the first aluminum content.

A laser or light emitter for operation at a cryogenic temperature includes a single quantum well layer, an n-type barrier layer directly on a first surface of the single quantum well layer, and a p-type barrier layer directly on a second surface of the single quantum well layer opposite the first surface of the single quantum well layer. The single quantum well layer is between the p-type barrier layer and the n-type barrier layer and the compositions of the n-type barrier layer and the p-type barrier layer are graded.

An optoelectronic component includes first and second semiconductor layers and an active layer that generates electromagnetic radiation, wherein the active layer is disposed between the first and second semiconductor layers, a recess in the first semiconductor layer, a front side provided for coupling out the electromagnetic radiation, a first electrical connection layer and a second electrical connection layer disposed on a rear side opposite the front side, wherein the first electrical connection layer is arranged at least partially in the recess, and a contact zone with a dopant of a second conductivity type different from the first conductivity type, wherein the contact zone adjoins the recess, and the first semiconductor layer and the second semiconductor layer are highly doped to prevent diffusion of the dopant from the contact zone into the first semiconductor layer and diffusion of the dopant from the contact zone into the second semiconductor layer.

A light emitting diode (LED) includes: a device substrate; a first semiconductor layer above the device substrate, and doped with an n-type dopant; a second semiconductor layer above the first semiconductor layer, and doped with a p-type dopant; an active layer between the first semiconductor layer and the second semiconductor layer and configured to provide light; a transparent electrode layer adjacent to an upper part of the second semiconductor layer; and a first electrode pad and a second electrode pad between the device substrate and the first semiconductor layer, the first electrode pad electronically connected with the first semiconductor layer and the second electrode pad electrically connected with the second semiconductor layer, wherein light provided by the active layer is irradiated to an outside in a direction from the active layer to the second semiconductor layer.