A semiconductor optical element includes: a first conductivity type semiconductor substrate; and a laminated body disposed on the first conductivity type semiconductor substrate. The laminated body includes, in the following order from a side of the first conductivity type semiconductor substrate: a first conductivity type semiconductor layer; an active layer; a second conductivity type semiconductor layer; and a second conductivity type contact layer. The second conductivity type semiconductor layer includes: a carbon-doped semiconductor layer in which carbon is doped as a dopant in a compound semiconductor; and a group 2 element-doped semiconductor layer in which a group 2 element is doped as a dopant in a compound semiconductor. The carbon-doped semiconductor layer is disposed at a position closer to the active layer than the group 2 element-doped semiconductor layer.

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

A semiconductor optical element includes: a first conductivity type semiconductor substrate; and a laminated body disposed on the first conductivity type semiconductor substrate. The laminated body includes, in the following order from a side of the first conductivity type semiconductor substrate: a first conductivity type semiconductor layer; an active layer; a second conductivity type semiconductor layer; and a second conductivity type contact layer. The second conductivity type semiconductor layer includes: a carbon-doped semiconductor layer in which carbon is doped as a dopant in a compound semiconductor; and a group 2 element-doped semiconductor layer in which a group 2 element is doped as a dopant in a compound semiconductor. The carbon-doped semiconductor layer is disposed at a position closer to the active layer than the group 2 element-doped semiconductor layer.

A semiconductor laser device lases in a multiple transverse mode and includes a stacked structure where a first conductivity-side semiconductor layer, an active layer, and a second conductivity-side semiconductor layer are stacked above a substrate. The second conductivity-side semiconductor layer includes a current block layer having an opening that delimits a current injection region. Side faces as a pair are formed in portions of the stacked structure that range from part of the first conductivity-side semiconductor layer to the second conductivity-side semiconductor layer. The active layer has a second width greater than a first width of the opening. The side faces in at least part of the first conductivity-side semiconductor layer are inclined to the substrate. A maximum intensity position in a light distribution of light guided in the stacked structure, in a direction of the normal to the substrate, is within the first conductivity-side semiconductor layer.

A nitride semiconductor light-emitting element includes an n-type cladding layer including n-type AlGaN and having a first Al composition ratio, and a multiple quantum well layer in which a plurality (number N) of barrier layers including AlGaN having a second Al composition ratio more than the first Al composition ratio and a plural (number N) well layers having an Al composition ratio less than the second Al composition ratio are stacked alternately in this order, wherein the second Al composition ratio of the plurality of barrier layers of the multiple quantum well layer increases at a predetermined increase rate from an n-type cladding layer side toward an opposite side to the n-type cladding layer side.

A semiconductor optical element includes: a first conductivity type semiconductor substrate; and a laminated body disposed on the first conductivity type semiconductor substrate. The laminated body includes, in the following order from a side of the first conductivity type semiconductor substrate: a first conductivity type semiconductor layer; an active layer; a second conductivity type semiconductor layer; and a second conductivity type contact layer. The second conductivity type semiconductor layer includes: a carbon-doped semiconductor layer in which carbon is doped as a dopant in a compound semiconductor; and a group 2 element-doped semiconductor layer in which a group 2 element is doped as a dopant in a compound semiconductor. The carbon-doped semiconductor layer is disposed at a position closer to the active layer than the group 2 element-doped semiconductor layer.

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.

The present invention relates to a device for generating laser radiation.

An object of the present invention is to indicate a laser diode which simultaneously has a high degree of efficiency and a low degree of far field divergence.

The diode laser according to the invention comprises a current barrier (5), characterized in that the current barrier (5) extends along a third axis (X), wherein the current barrier (5) has at least one opening, and a first width (W1) of the opening of the current barrier (5) along the third axis (X) is smaller than a second width (W2) of the metal p-contact (8) along the third axis (X).

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 spot-size converter includes first and second waveguide structures. The first waveguide structure extends longitudinally along a waveguide axis from a first end to a second end and is configured to support a first optical mode at the first end. The second waveguide structure is formed within the first waveguide structure. The second waveguide structure extends longitudinally between the first end and the second end. The second waveguide structure is configured to support a second optical mode at the second end. The second optical mode has a different diameter than the first optical mode. The second waveguide structure includes a waveguide core that has a first cross-sectional area in a first plane normal to the waveguide axis at the first end and a second cross-sectional area in a second plane normal to the waveguide axis at the second end. The second cross-sectional area is larger than the first cross-sectional area.