Degradation of laser characteristics and increase in variations in characteristics are reduced. A semiconductor apparatus (100) includes a semiconductor chip including a semiconductor substrate (1) including a group-III nitride semiconductor and a laminate structure (2) located on a first surface (1a) of the semiconductor substrate (1), and on at least one of side surfaces of the semiconductor chip orthogonal to the first surface (1a), plural groove-like machining traces (105) are provided at a pitch of 2 μm (micrometers) or more but 30 μm or less in a direction parallel to a second surface (1b) of the semiconductor substrate (1) opposite to the first surface (1a) of the semiconductor substrate (1), the groove-like machining traces extending from the second surface (1b) to a third surface (1a) of the laminate structure (2) opposite to a surface of the laminate structure (2) contacting the first surface (1a).

A device including a non-polarization material includes a number of layers. A first layer of silicon (100) defines a U-shaped groove having a bottom portion (100) and silicon sidewalls (111) at an angle to the bottom portion (100). A second layer of a patterned dielectric on top of the silicon (100) defines vertical sidewalls of the U-shaped groove. A third layer of a buffer covers the first layer and the second layer. A fourth layer of gallium nitride is deposited on the buffer within the U-shaped groove, the fourth layer including cubic gallium nitride (c-GaN) formed at merged growth fronts of hexagonal gallium nitride (h-GaN) that extend from the silicon sidewalls (111), wherein a deposition thickness (h) of the gallium nitride above the first layer of silicon (100) is such that the c-GaN completely covers the h-GaN between the vertical sidewalls.

A terahertz quantum cascade laser device is provided comprising a substrate having a top substrate surface, a bottom substrate surface, and an exit facet extending between the top substrate surface and the bottom substrate surface at an angle θ.sub.tap. The device comprises a waveguide structure having a top surface, a bottom surface, a front facet extending between the top surface and the bottom surface and positioned proximate to the exit facet, and a back facet extending between the top surface and the bottom surface and oppositely facing the front facet. The waveguide structure comprises a quantum cascade laser structure configured to generate light comprising light of a first frequency ω.sub.1, light of a second frequency ω.sub.2, and light of a third frequency ω.sub.THz, wherein ω.sub.THz=ω.sub.1−ω.sub.2; an upper cladding layer; and a lower cladding layer. The device comprises a distributed feedback grating layer configured to provide optical feedback for one or both of the light of the first frequency ω.sub.1 and the light of the second frequency ω.sub.2 and to produce lasing at one or both of the first frequency ω.sub.1 and the second frequency ω.sub.2, thereby resulting in laser emission at the third frequency ω.sub.THz at a Cherenkov angle θ.sub.THz through the bottom surface of the waveguide structure into the substrate and exiting the substrate through the exit facet. The device comprises a high-reflectivity coating on the front facet of the waveguide structure.

A device includes an illumination device for emitting an illumination beam. The illumination device includes an emitter array including multiple light emitters; and a micro-lens array (MLA) including multiple micro-lenses. The MLA is positioned to receive light emitted from the emitter array. Light from the MLA forms the illumination beam. A first region of the MLA is offset from the emitter array by a first offset amount, and a second region of the MLA is offset from the emitter array by a second offset amount different than the first offset amount.

A quantum cascade laser includes a semiconductor substrate, an optical waveguide formed on a first surface of the semiconductor substrate, and a temperature adjusting member. The optical waveguide includes a first region and a second region located on one side with respect to the first region in the optical waveguide direction of the optical waveguide. The first region generates a first light having a first wavelength, and the second region generates a second light having a second wavelength. The optical waveguide generates an output light having a frequency corresponding to a difference between the first wavelength and the second wavelength by difference-frequency generation. A recess for suppressing heat transfer between the first region and the second region is formed at a second surface of the semiconductor substrate. The temperature adjusting member includes a first temperature adjusting member for adjusting the temperature of the second region.

Ina light emitting device, a first diametrical size that is the largest size of a columnar part between a substrate side of a light emitting layer and an opposite side of the substrate, the columnar part has a size no larger than the first diametrical size in an area between the substrate side of the light emitting layer and the substrate side of a first semiconductor layer, the columnar part has a size smaller than the first diametrical size in the area between the substrate side of the light emitting layer and the substrate side of the first semiconductor layer, the columnar part has a size no larger than the first diametrical size in an area between the opposite side to the substrate of the light emitting layer, and an opposite side to the substrate of a second semiconductor layer, and the columnar part has a size smaller than the first diametrical size in the area between the opposite side to the substrate of the light emitting layer in the laminating direction, and the opposite side to the substrate of the second semiconductor layer.

A light emitting element comprising a layered structure configured by layering a first light reflecting layer 41 configured by layering a plurality of thin films, a light emitting structure 20, and a second light reflecting layer 42 configured by layering a plurality of thin films, wherein the light emitting structure 20 is configured by layering, from the first light reflecting layer side, a first compound semiconductor layer 21, an active layer 23, and a second compound semiconductor layer 22, a second electrode 32 and an intermediate layer 70 are formed between the second compound semiconductor layer 22 and the second light reflecting layer 42 from the second compound semiconductor layer side, and the value of a surface roughness of a second surface 72 of the intermediate layer 70 in contact with the second light reflecting layer 42 is less than the value of a surface roughness of a first surface 71 of the intermediate layer 70 facing the second electrode 32.

A semiconductor light emitting device includes a substrate, and an array including three or more light emitting elements which are aligned above and along a main surface of a substrate and each emit light. The light emitting elements each include a clad layer of a first conductivity type, an active layer containing In, and a clad layer of a second conductivity type disposed above the substrate sequentially from the substrate. Among the light emitting elements, the compositional ratio of In in the active layer is smaller in the light emitting element located in a central area in an alignment direction than that in the light emitting elements located in both end areas in the alignment direction.

Coupled-cavity vertical cavity surface emitting lasers (VCSELs) are provided by the present disclosure. The coupled-cavity VCSEL can comprise a VCSEL having a first mirror, a gain medium disposed above the first mirror, and a second mirror disposed above the gain medium, wherein a first cavity is formed by the first mirror and the second mirror. A second cavity is optically coupled to the VCSEL and configured to reflect light emitted from the VCSEL back into the first cavity of the VCSEL. In some embodiments, the second cavity can be an external cavity optically coupled to the VCSEL through a coupling component. In some embodiments, the second cavity can be integrated with the VCSEL to form a monolithic coupled-cavity VCSEL. A feedback circuit can control operation of the coupled-cavity VCSEL so the output comprises a target high frequency signal.

Provided is a back side emitting light source array device and an electronic apparatus, the back side emitting light source array device includes a substrate, a distributed Bragg reflector (DBR) provided on a first surface of the substrate, a plurality of gain layers which are provided on the DBR, the plurality of gain layers being spaced apart from one another, and each of the plurality of gain layers being configured to individually generate light, and a nanostructure reflector provided on the plurality of gain layers opposite to the DBR, and including a plurality of nanostructures having a sub-wavelength shape dimension, wherein a reflectivity of the DBR is less than a reflectivity of the nanostructure reflector such that the light generated is emitted through the substrate.