A light emitting device includes a wiring substrate, a light emitting element array that includes a first side surface and a second side surface facing each other, and a third side surface and a fourth side surface connecting the first side surface and the second side surface to each other and facing each other, the light emitting element array being provided on the wiring substrate, a driving element that is provided on the wiring substrate on the first side surface side and drives the light emitting element array, a first circuit element and a second circuit element that are provided on the wiring substrate on the second side surface side to be arranged in a direction along the second side surface, and a wiring member that is provided on the third side surface side and the fourth side surface side and extends from a top electrode of the light emitting element array toward an outside of the light emitting element array.

The present disclosure relates to index guided semiconductor laser devices supporting wide single lateral mode operation for high power operation. A narrow channel ridge waveguide structure is presented which devices can be configured as single lateral multi-spectral high power semiconductor lasers, single frequency lasers, gain chips and semiconductor amplifiers. More specifically it relates to a means for increasing the lateral mode size over that of conventional index guided structures to increase the average output power typically limed by Catastrophic Optical Damage (COD) at the laser facet or by intensity related effects. This potentially allows the overall laser cavity length to be shortened for a given output power level to stabilize frequency locking with internal or external gratings to improve single frequency operation.

The present disclosure is generally directed to an EML with a filter layer disposed between an active region of the EML and a substrate of the EML to absorb a portion of unmodulated light energy, and preferably the unmodulated light energy caused by transverse electric (TE) substrate mode. The filter layer preferably comprises a material with an energy band gap (Eg) that is less than the energy band gap of the predetermined channel wavelength to absorb unmodulated laser light.

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.

A semiconductor laser is formed to include a current blocking layer that is positioned below the active region of the device and used to minimize current spreading beyond the defined dimensions of an output beam's optical mode. When used in conjunction with other current-confining structures typically disposed above the active region (e.g., ridge waveguide, electrical isolation, oxide aperture), the inclusion of the lower current blocking layer improves the efficiency of the device. The current blocking layer may be used in edge-emitting devices or vertical cavity surface-emitting devices, and also functions to improve mode shaping and reduction of facet deterioration by directing current flow away from the facets.

An edge-emitting semiconductor laser and a method for operating a semiconductor laser are disclosed. In an embodiment, the edge-emitting semiconductor laser includes an active zone within a semiconductor layer sequence and a stress layer. The active zone is configured for being energized only in a longitudinal strip perpendicular to a growth direction of the semiconductor layer sequence. The semiconductor layer sequence has a constant thickness throughout in the region of the longitudinal strip so that the semiconductor laser is gain-guided. The stress layer may locally stress the semiconductor layer sequence in a direction perpendicular to the longitudinal strip and in a direction perpendicular to the growth direction. A refractive index of the semiconductor layer sequence, in regions which, seen in plan view, are located next to the longitudinal strip, for the laser radiation generated during operation is reduced by at least 2×10.sup.−4 and by at most 5×10.sup.−3.

Solid-state optical devices (10) enable tuning of an electrically tunable depletion region (200) to reduce and block lateral (in-junction) carrier spreading. This capability reduces the negative effects of gain-guiding in the junction plane and reduces an astigmatism of an emitted light beam. The tunable depletion region is created by forming a highly resistive Schottky contact (105, 110) or metal-insulator-semiconductor (MIS) structure (205, 210) next to a waveguide (optical mode propagation) and current injection region (215), where lateral spread due to diffusion is expected. The depletion region area is tuned by applying a bias to the highly resistive Schottky contact or the MIS contact structure. Such contacts or similar lossy structures reduce in-junction plane gain-guiding also when unbiased by creating additional optical loss for the mode, thus reducing the effective carrier density participating in light generation, thereby reducing astigmatism.

A Schottky diode is monolithically integrated into the core of an infrared semiconductor laser (e.g., a quantum cascade laser) to create a heterodyned infrared transceiver. The internal mode field of the infrared semiconductor laser couples to an embedded Schottky diode and can mix the infrared fields to generate a response at the difference frequency.

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 semiconductor laser diode is provided. A semiconductor layer sequence has semiconductor layers applied vertically one above the other. An active layer includes an active region having a width of greater than or equal to 30 μm emitting laser radiation during operation via a radiation coupling-out surface. The radiation coupling-out surface is formed by a lateral surface of the semiconductor layer sequence and forms, with an opposite rear surface, a resonator having lateral gain-guiding in a longitudinal direction. The semiconductor layer sequence is heated in a thermal region of influence by reason of the operation. A metallization layer is in direct contact with a top side of the semiconductor layer sequence.