A semiconductor light-emitting element includes a light emission layer including a group III nitride semiconductor; an electron barrier layer disposed above the light emission layer and including a group III nitride semiconductor containing Al; and a p-type clad layer disposed above and in contact with the electron barrier layer, wherein the electron barrier layer and the p-type clad layer contain Mg as a dopant, and the p-type clad layer includes a high carbon concentration region containing carbon and a low carbon concentration region having a carbon concentration lower than a carbon concentration of the high carbon concentration region, in a stated order from an electron barrier layer side.

A light source system or apparatus configured with an infrared illumination source includes a gallium and nitrogen containing laser diode based white light source. The light source system includes a first pathway configured to direct directional electromagnetic radiation from the gallium and nitrogen containing laser diode to a first wavelength converter and to output a white light emission. In some embodiments infrared emitting laser diodes are included to generate the infrared illumination. In some embodiments infrared emitting wavelength converter members are included to generate the infrared illumination. In some embodiments a second wavelength converter is optically excited by a UV or blue emitting gallium and nitrogen containing laser diode, a laser diode operating in the long wavelength visible spectrum such as a green laser diode or a red laser diode, by a near infrared emitting laser diode, by the white light emission produced by the first wavelength converter, or by some combination thereof. A beam shaper may be configured to direct the white light emission and an infrared emission for illuminating a target of interest and transmitting a data signal. In some configurations, sensors and feedback loops are included.

A semiconductor laser element includes an n-side semiconductor layer, an active layer, and a p-side semiconductor layer. A least a portion of the p-side semiconductor layer forms a ridge projecting upward. The p-side semiconductor layer includes an undoped first part, an electron barrier layer containing a p-type impurity and having a larger band gap energy than the first part, and a second part having at least one p-type semiconductor layer. The first part includes an undoped p-side composition graded layer in which a band gap energy increases towards the electron barrier layer, and an undoped p-side intermediate layer disposed on or above the p-side composition graded layer. A lower end of the ridge is positioned at the p-side intermediate layer.

A light emitting device includes a substrate, and a laminated structure provided to the substrate, and including a columnar part, wherein the columnar part includes a first GaN layer having a first conductivity type, a second GaN layer having a second conductivity type different from the first conductivity type, and a light emitting layer disposed between the first GaN layer and the second GaN layer, the first GaN layer is disposed between the substrate and the light emitting layer, the light emitting layer has a first well layer as an InGaN layer, the first GaN layer has a c-face region, the first GaN layer has a crystal structure of a cubical crystal, and has a first layer constituting the c-face region, and a second layer as a GaN layer having a crystal structure of a hexagonal crystal is disposed between the first layer and the first well layer.

A light source or system configured to emit visible white light and infrared emissions includes a laser diode, a wavelength converter, and an infrared emitting laser diode.

A light source system or apparatus configured with an infrared illumination source includes a gallium and nitrogen containing laser diode based white light source. The light source system includes a first pathway configured to direct directional electromagnetic radiation from the gallium and nitrogen containing laser diode to a first wavelength converter and to output a white light emission. In some embodiments infrared emitting laser diodes are included to generate the infrared illumination. In some embodiments infrared emitting wavelength converter members are included to generate the infrared illumination. In some embodiments a second wavelength converter is optically excited by a UV or blue emitting gallium and nitrogen containing laser diode, a laser diode operating in the long wavelength visible spectrum such as a green laser diode or a red laser diode, by a near infrared emitting laser diode, by the white light emission produced by the first wavelength converter, or by some combination thereof. A beam shaper may be configured to direct the white light emission and an infrared emission for illuminating a target of interest and transmitting a data signal. In some configurations, sensors and feedback loops are included.

An optical device has a gallium and nitrogen containing substrate including a surface region and a strain control region, the strain control region being configured to maintain a quantum well region within a predetermined strain state. The device also has a plurality of quantum well regions overlying the strain control region.

A semiconductor crystal substrate includes a crystal substrate that is formed of a material including GaSb or InAs, a first buffer layer that is formed on the crystal substrate and formed of a material including GaSb, the first buffer layer having n-type conductivity, and a second buffer layer that is formed on the first buffer layer and formed of a material including GaSb, the second buffer layer having p-type conductivity.

In order to provide a QCL element operating in the near-infrared wavelength range, the present disclosure provides a quantum cascade laser element 1000 having a semiconductor superlattice structure (QCL structure 100) sandwiched between a pair of conductive sections 20 and 30. The semiconductor superlattice structure serves as an active region that emits electromagnetic waves. The active region has a plurality of unit structures 10U that are stacked on top of each other. Each unit structure includes four well layers 10W1-10W4 of a composition of Al.sub.xGa.sub.1-xN, separated from each other by barrier layers 10B1-10B5 of a composition of Al.sub.yGa.sub.1-yN with 0≤x<y≤1. Both of the conductive sections in the pair of conductive sections have a refractive index lower than that of the active region in which doped TCO inserted as a key role.

The semiconductor light-emitting element includes: a stacking structure having a substrate and a semiconductor layer between a first surface and a second surface that face each other in order from a side on which the first surface is located, the substrate including a compound semiconductor, and the semiconductor layer being crystal-grown on the substrate and including a light-emitting region; a first depression formed on at least a portion of a first edge adjacent to the second surface of the stacking structure; and a second depression formed on a second edge extending along a thickness direction of the stacking structure.