Abstract: A semiconductor laser includes: a multiple quantum well active layer that is formed on a semiconductor substrate comprised by GaAs and includes well layers having GaInAsP that has a tensile strain against the GaAs, and a barrier layer having AlGaInP that has substantially zero strain against the GaAs, the well layers and the barrier layer being alternately stacked; a pair of first AlGaInP layers that has substantially zero strain against the GaAs, and is provided so that the first AlGaInP layers contact upper and lower surfaces of the multiple quantum well active layer respectively; and a pair of second AlGaInP layers that has a compressive strain against the GaAs, and is provided so that the second AlGaInP layers contact the pair of first AlGaInP layers respectively.

Abstract: In a III-nitride semiconductor laser device, a laser structure includes a support base with a semipolar primary surface comprised of a III-nitride semiconductor, and a semiconductor region provided on the semipolar primary surface of the support base. First and second dielectric multilayer films for an optical cavity of the nitride semiconductor laser device are provided on first and second end faces of the semiconductor region, respectively. The semiconductor region includes a first cladding layer of a first conductivity type gallium nitride-based semiconductor, a second cladding layer of a second conductivity type gallium nitride-based semiconductor, and an active layer provided between the first cladding layer and the second cladding layer. The first cladding layer, the second cladding layer, and the active layer are arranged in an axis normal to the semipolar primary surface.

Abstract: By making use of a vertical cavity surface emitting laser element (100) in accordance with the present invention, it becomes able to suppress as properly an occurrence of any dislocation therein even in a case where there is formed a DBR mirror onto a substrate (1), by designing to be set for between an average of strain in a DBR mirror at the lower side thereof (2) and a layer thickness of such the DBR mirror at the lower side thereof (2) in reference to a curvature of the substrate (1) in order to be satisfied a predetermined condition, and then by performing an addition of nitrogen into the DBR mirror at the lower side thereof (2) with a composition thereof that corresponds to the designed average of strain in the DBR mirror at the lower side thereof (2) to be set therefor, such as the composition of between 0.028% and 0.

Abstract: A semiconductor light emitting device includes: a stacked body including a first and a second semiconductor layers of a first and second conductivity types respectively, and a light emitting layer provided between thereof; a first and a second electrodes in contact with the first and second semiconductor layers respectively. Light emitted is resonated between first and second end surfaces of the stacked body opposed in a first direction. The second semiconductor layer includes a ridge portion and a wide portion. A width of the ridge portion along a second direction perpendicular to the first and the stacking directions is narrower on the second electrode side than on the light emitting layer side. A width of the wide portion along the second direction is wider than the ridge portion.

Abstract: A surface emitting laser includes a pair of multilayer mirrors disposed opposing to each other, and an active layer disposed between the multilayer mirrors. In at least one multilayer mirror of the pair of multilayer mirrors, a plurality of first pair layers are stacked, each first pair layer is formed from a high-refractive index layer having a first strain and a low-refractive index layer having a second strain; and a second pair layer is included, the second pair layer is formed of one of the high-refractive index layer and the low-refractive index layer of the first pair layer in which one of the high-refractive index layer and the low-refractive index layer of the first pair layer is replaced with a layer formed from a quaternary or higher mixed crystal semiconductor material having a third strain.

Abstract: A polarization-independent SOA having an InP substrate used as a semiconductor substrate, and an active layer taking an MQW structure formed of a barrier layer made of GaInAs with tensile strain applied thereto and a well layer made of GaInNAs with no strain applied thereto alternately laminated in a plurality of layers, here, four layers of the well layer and five layers of the barrier layer are alternately laminated, is proposed.

Abstract: A VCSEL with undoped top mirror. The VCSEL is formed from an epitaxial structure deposited on a substrate. A doped bottom mirror is formed on the substrate. An active layer that includes quantum wells is formed on the bottom mirror. A periodically doped conduction layer is formed on the active layer. The periodically doped conduction layer is heavily doped at locations where the optical energy is at a minimum when the VCSEL is in operation. A current aperture is used between the conduction layer and the active region. An undoped top mirror is formed on the heavily doped conduction layer.

Abstract: A quantum cascade laser structure in accordance with the invention comprises a number of cascades (100), each of which comprises a number of alternately arranged quantum wells (110a to 110j) and barrier layers (105 to 105j). The material of at least one quantum well (110a to 110j) as well as the material of at least one barrier layer (105 to 105j) is under mechanical strain, with the respective strain being either a tensile strain or a compression strain. The quantum wells (110a to 110j) and barrier layers (105 to 105j) are engineered in the quantum cascade laser structure in accordance with the invention so that existing strains are largely compensated within a cascade (100). In the quantum cascade laser structure in accordance with the invention, each material of the quantum wells (110a to 110j) has only one constituent material and the material of at least one barrier layer (105d, 105e, 105f) has at least two constituent materials (111a, 111b, 112a, 112b, 113a, 113b).

Abstract: Strain modulated nanostructures for optoelectronic devices and associated systems and methods are disclosed. A semiconductor laser in accordance with one embodiment of the disclosure, for example, comprises an active region having a nanowire structure formed from a semiconductor material. The nanowire structure of the semiconductor material has a bandgap that is indirect in a first strain state. The laser further includes a straining unit coupled to the active region. The straining unit is configured to modulate the nanowire structure such that the nanowire structure reaches a second strain state in which the bandgap becomes direct or substantially direct and, in operation, emits photons upon electron-hole recombination.

Abstract: A semiconductor laser device capable of easily obtaining a desired hue is obtained. This semiconductor laser device (100) includes a green semiconductor laser element (30) having one or a plurality of laser beam emitting portions, a blue semiconductor laser element (50) having one or a plurality of laser beam emitting portions, and a red semiconductor laser element (10) having one or a plurality of laser beam emitting portions.

Abstract: A method and structure for producing lasers having good optical wavefront characteristics, such as are needed for optical storage includes providing a laser wherein an output beam emerging from the laser front facet is essentially unobstructed by the edges of the semiconductor chip in order to prevent detrimental beam distortions. The semiconductor laser structure is epitaxially grown on a substrate with at least a lower cladding layer, an active layer, an upper cladding layer, and a contact layer. Dry etching through a lithographically defined mask produces a laser mesa of length lc and width bm. Another sequence of lithography and etching is used to form a ridge structure with width won top of the mesa. The etching step also forming mirrors, or facets, on the ends of the laser waveguide structures. The length ls and width bs of the chip can be selected as convenient values equal to or longer than the waveguide length lc and mesa width bm, respectively.

Abstract: Semiconductor devices such as VCSELs, SELs, LEDs, and HBTs are manufactured to have a wide bandgap material near a narrow bandgap material. Electron injection is improved by an intermediate structure positioned between the wide bandgap material and the narrow bandgap material. The intermediate structure is an inflection, such as a plateau, in the ramping of the composition between the wide bandgap material and the narrow bandgap material. The intermediate structure is highly doped and has a composition with a desired low electron affinity. The injection structure can be used on the p-side of a device with a p-doped intermediate structure at high hole affinity.

Abstract: A nitride semiconductor laser device includes, on a first principle face of the (0001) of a nitride semiconductor substrate, a nitride semiconductor layer having a first conductivity type, an active layer, and a nitride semiconductor layer having a second conductivity type that is different from the first conductivity type, and being formed a stripe ridge on the surface thereof. The (000-1) face and an inclined face other than the (000-1) face are exposed on a second principal face of the nitride semiconductor substrate. The inclined face other than the (000-1) face represents no less than 0.5% over the surface area of the second principal face.

Abstract: The invention is a photonic crystal laser including a photonic crystal slab laser cavity including InGaP/InGaAlP crystalline layers, the InGaP/InGaAlP crystalline layers having a relaxed strain at one or more etched surfaces and a higher strain at a plurality of quantum wells and at a distance from the one or more etched surfaces. The photonic crystal laser also includes electrical pads configured to receive an electrical signal the electrical pads attached to the photonic crystal slab laser cavity via an insulating layer, the photonic crystal laser configured to emit a laser light in response to the electrical signal. In another aspect, the invention features a photonic crystal detector including a photonic crystal slab cavity including InGaP/InGaAlP crystalline layers. In yet another aspect, the invention features a process to fabricate a photonic crystal laser cavity.

Abstract: A laser diode comprising a first separate confinement heterostructure and an active region on the first separate confinement heterostructure. A second separate confinement heterostructure is on the active region and one or more epitaxial layers is on the second separate confinement heterostructure. A ridge is formed in the epitaxial layers with a first mesa around the ridge. The first mesa is 0.1 to 0.2 microns above the second confinement heterostructure.

Abstract: Provided is a process for producing a surface emitting laser including a surface relief structure provided on laminated semiconductor layers, including the steps of transferring, to a first dielectric film, a first pattern for defining a mesa structure and a second pattern for defining the surface relief structure in the same process; and forming a second dielectric film on the first dielectric film and a surface of the laminated semiconductor layers to which the first pattern and the second pattern have been transferred. Accordingly, a center position of the surface relief structure can be aligned with a center position of a current confinement structure at high precision.

Abstract: A semiconductor laser comprises: a semiconductor substrate and a lower cladding layer, an active layer, and an upper cladding layer on the semiconductor substrate. The layers form a resonator having opposed end surfaces. A ridge includes part of the upper cladding layer. The upper cladding layer in the ridge, proximate the resonator end surfaces, is thicker than the upper cladding layer in the ridge at a central part of the resonator.

Abstract: A laser diode device with which a low voltage is realized is provided. The laser diode device includes: a substrate; a semiconductor laminated structure including a first conductive cladding layer, an active layer, and a second conductive cladding layer on one face side of the substrate and having a contact layer as the uppermost layer, in which a protrusion is formed in the contact layer and the second conductive cladding layer; and an electrode provided on the contact layer. The contact layer has a concavo-convex structure on a face on the electrode side, and the electrode is contacted with the contact layer at contact points of a top face, a side face, and a bottom face of the concavo-convex structure.

Abstract: In a constitution where a first clad layer is formed on a semiconductor substrate, an active layer having the strained multiple quantum well structure is formed on the first clad layer, and a second clad layer is formed on the active layer, the sum of products of strain amounts and film thickness in the active layer is set to a negative value.

Abstract: Provided are a nitride semiconductor laser chip with a reliability improved by relieving stress due to strain within the nitride semiconductor laser chip, a manufacturing method thereof, and a nitride semiconductor laser device. The nitride semiconductor laser chip comprises: a substrate; and a laminated structure provided on a main surface of the substrate and including a nitride semiconductor layer. In the laminated structure, at least one crack parallel to a resonator end face is formed. By forming a crack within a laser chip, stress due to strain is relieved; therefore, it is possible to obtain a laser chip having a high reliability.

Abstract: A buried semiconductor laser exhibiting a reduced dislocation of a contact layer is achieved. A buried semiconductor laser, comprising: an n-type indium phosphide (InP) substrate; an active layer disposed on the n-type InP substrate; block layers provided so as to bilaterally disposed on both sides of the active layer; a clad layer provided so as to cover the active layer and the block layers; and a p-type gallium indium arsenide (InGaAs) contact layer provided on the clad layer, wherein the p-type InGaAs contact layer has a compressive strain.

Abstract: A laser diode and method for fabricating same, wherein the laser diode generally comprises an InGaN compliance layer on a GaN n-type contact layer and an AlGaN/GaN n-type strained super lattice (SLS) on the compliance layer. An n-type GaN separate confinement heterostructure (SCH) is on said n-type SLS and an InGaN multiple quantum well (MQW) active region is on the n-type SCH. A GaN p-type SCH on the MQW active region, an AlGaN/GaN p-type SLS is on the p-type SCH, and a p-type GaN contact layer is on the p-type SLS. The compliance layer has an In percentage that reduces strain between the n-type contact layer and the n-type SLS compared to a laser diode without the compliance layer. Accordingly, the n-type SLS can be grown with an increased Al percentage to increase the index of refraction. This along with other features allows for reduced threshold current and voltage operation.

Abstract: A semiconductor light emitter includes a quantum well active layer which includes nitrogen and at least one other Group-V element, and barrier layers which are provided alongside the quantum well active layer, wherein the quantum well active layer and the barrier layers together constitute an active layer, wherein the barrier layers are formed of a Group-III-V mixed-crystal semiconductor that includes nitrogen and at least one other Group-V element, a nitrogen composition thereof being smaller than that of the quantum well active layer.

Abstract: The general field of the invention is that of tunable semiconductor devices with distributed Bragg grating, and more particularly that of tunable lasers with distributed Bragg grating termed DBRs. The device according to the invention comprises a passive Bragg section comprising a material whose optical index variations are controlled by an injection current, said material of the Bragg section is a strained bulk material, the strain applied to the bulk material being equal to at least 0.1%.

Abstract: A semiconductor laser comprises an electrically isolated active section and at least one noise reducing section and operates on a ground state transition of a quantum dot array having inhomogeneous broadening greater than 10 nm. The laser preferably emits more than 10 optical modes such that a total relative intensity noise of each optical mode is less than 0.2% in the 0.001 GHz to 10 GHz range. The spectral power density is preferably higher than 2 mW/nm. An optical transmission system and a method of operating a quantum dot laser with low relative intensity noise of each optical mode are also disclosed.

Abstract: A semiconductor laser includes: a multiple quantum well active layer that is formed on a semiconductor substrate comprised by GaAs and includes well layers having GaInAsP that has a tensile strain against the GaAs, and a barrier layer having AlGaInP that has substantially zero strain against the GaAs, the well layers and the barrier layer being alternately stacked; a pair of first AlGaInP layers that has substantially zero strain against the GaAs, and is provided so that the first AlGaInP layers contact upper and lower surfaces of the multiple quantum well active layer respectively; and a pair of second AlGaInP layers that has a compressive strain against the GaAs, and is provided so that the second AlGaInP layers contact the pair of first AlGaInP layers respectively.

Abstract: A surface-emission laser diode comprises a cavity region over a semiconductor substrate and includes an active layer containing at least one quantum well active layer producing a laser light and a barrier layer, a spacer layer is provided in the vicinity of the active layer and formed of at least one material, an upper and lower reflectors are provided at a top part and a bottom part of the cavity region, the cavity region and the upper and lower reflectors form a mesa structure over the semiconductor substrate, the upper and lower reflectors being formed of a semiconductor distributed Bragg reflector having a periodic change of refractive index and reflecting incident light by interference of optical waves, at least a part of the semiconductor distributed Bragg reflector is formed of a layer of small refractive index of AlxGa1-xAs (0<x?1) and a layer of large refractive index of AlyGa1-yAs (0?y<x?1), the lower reflector is formed of a first lower reflector having a low-refractive index layer of AlAs an

Abstract: There is disclosed a monolithic semiconductor laser which is provided with an AlGaAs based semiconductor laser element (10a) and an InGaAlP based semiconductor laser element (10b) formed on a semiconductor substrate (1). The AlGaAs based semiconductor laser element (10a) is composed of an infrared light emitting layer forming portion (9a), which has an n-type cladding layer (2a), an active layer (3a) and a p-type cladding layer (4a) formed so as to have a ridge portion, and a current constriction layer (5a) provided on sides of the ridge portion, while the InGaP based semiconductor laser element (10b) is composed of a red light emitting layer forming portion (9a), which has an n-type cladding layer (2b), an active layer (3b) and a p-type cladding layer (4b) formed so as to have a ridge portion, and a current constriction layer (5b) provided on sides of the ridge portion.

Abstract: This semiconductor laser device includes a substrate, a green semiconductor laser element, formed on a surface of the substrate, including a first active layer having a first major surface of a semipolar plane and a blue semiconductor laser element, formed on a surface of the substrate, including a second active layer having a second major surface of a surface of the semipolar plane, while the first active layer includes a first well layer having a compressive strain and having a thickness of at least about 3 nm, and the second active layer includes a second well layer having a compressive strain.

Abstract: The AlGaN upper cladding layer of a nitride laser diode is replaced by a non-epitaxial layer, such as metallic silver. If chosen to have a relatively low refractive index value, the mode loss from absorption in the non-epitaxial cladding layer is acceptably small. If also chosen to have a relatively high work-function, the non-epitaxial layer forms an electrical contact to the nitride semiconductors. An indium-tin-oxide layer may also be employed with the non-epitaxial cladding layer.

Abstract: A surface-emission laser diode comprises a cavity region over a semiconductor substrate and includes an active layer containing at least one quantum well active layer producing a laser light and a barrier layer, a spacer layer is provided in the vicinity of the active layer and formed of at least one material, an upper and lower reflectors are provided at a top part and a bottom part of the cavity region, the cavity region and the upper and lower reflectors form a mesa structure over the semiconductor substrate, the upper and lower reflectors being formed of a semiconductor distributed Bragg reflector having a periodic change of refractive index and reflecting incident light by interference of optical waves, at least a part of the semiconductor distributed Bragg reflector is formed of a layer of small refractive index of AlxGa1-xAs (0<x?1) and a layer of large refractive index of AlyGa1-yAs (0?y<x?1), the lower reflector is formed of a first lower reflector having a low-refractive index layer of AlAs an

Abstract: An improved VECSEL device is provided in which the gain of each of the quantum well layers can be increased in a periodic gain structure. A vertical external cavity surface emitting laser (VECSEL) device comprising: a substrate; a bottom DBR mirror formed on the substrate; a multiple quantum well layer formed on the bottom DBR mirror and comprising: a plurality of quantum well layers; first and second strain compensation layers sequentially formed above and below each of the quantum well layers to gradually relieve the strain of the quantum well layers; a capping layer formed on the multiple quantum well layer; an optical pump radiating a pump beam to the surface of the capping layer; and an external cavity mirror separated from and facing the bottom DBR mirror.

Abstract: An oscillator including a substrate and a resonant tunneling diode including a gain medium provided on the substrate. The gain medium includes at least two quantum well layers and plural barrier layers for separating the quantum well layers from each other. The quantum well layers each have one of a compressive strain and a tensile strain. The plural barrier layers that sandwich the quantum well layers having the strain have a strain in a direction opposite to the direction of the strain of the quantum well layers.

Abstract: Misfit dislocations are redirected from the buffer/Si interface and propagated to the Si substrate due to the formation of bubbles in the substrate. The buffer layer growth process is generally a thermal process that also accomplishes annealing of the Si substrate so that bubbles of the implanted ion species are formed in the Si at an appropriate distance from the buffer/Si interface so that the bubbles will not migrate to the Si surface during annealing, but are close enough to the interface so that a strain field around the bubbles will be sensed by dislocations at the buffer/Si interface and dislocations are attracted by the strain field caused by the bubbles and move into the Si substrate instead of into the buffer epi-layer. Fabrication of improved integrated devices based on GaN and Si, such as continuous wave (CW) lasers and light emitting diodes, at reduced cost is thereby enabled.

Abstract: A surface emitting semiconductor device comprises: a semiconductor region including an active layer; a first DBR having first layers and second layers; and a second DBR. The first and second layers are alternately arranged, and the first layers are made of dielectric material. The first DBR, semiconductor region and second DBR are sequentially arranged along a predetermined axis, and the semiconductor region is provided between the first DBR and the second DBR. The cross section of the first DBR is taken along a reference plane perpendicular to the predetermined axis. The distance between two points on an edge of the cross section takes a first value in a direction of an X-axis of a two-dimensional XY orthogonal coordinate system defined on the reference plane, and the distance between two points on the edge takes a second value in a direction of a Y-axis of the above coordinate system. The first value is different from the second value.

Abstract: A n-type layer, a multiquantum well active layer comprising a plurality of pairs of an InGaN well layer/InGaN barrier layer, and a p-type layer are laminated on a substrate to provide a nitride semiconductor light emitting element. A composition of the InGaN barrier included in the multiquantum well active layer is expressed by InxGa1-xN (0.04?x?0.1), and a total thickness of InGaN layers comprising an In composition ratio within a range of 0.04 to 0.1 in the light emitting element including the InGaN barrier layers is not greater than 60 nm.

Abstract: A semiconductor light emitting device includes: a substrate; a first clad layer formed above the substrate and made of AlGaInP mixed crystal of a first conductivity type; an active layer formed on the first clad layer and made of AlGaInP mixed crystal; and a second clad layer formed on the active layer and made of AlGaInP mixed crystal of a second conductivity type opposite to the first conductivity type, wherein the first clad layer and the second clad layer each have a band gap wider than a band gap of the active layer, and at least one of the active layer and the first and second clad layers is doped with arsenic at an impurity concentration level not changing the band gap. Carbon capturing is suppressed, and surface morphology is suppressed from being degraded.

Abstract: A semiconductor laser device includes a multilayer structure made of group III nitride semiconductors formed on a substrate. The multilayer structure includes a MQW active layer, and also includes a step region selectively formed in an upper portion thereof. In another upper portion of the multilayer structure, a ridge stripe portion including a waveguide, which extends in parallel to a principal surface of the multilayer structure, is formed. In the vicinity of the step region, a first region, in which the MQW active layer has a bandgap energy of Eg1, is formed, and a second region, which is adjacent to the first region and in which the MQW active layer has a bandgap energy of Eg2 (Eg2<Eg1), is formed. The waveguide, which is formed so as to include the first and second regions and so as not to include the step region, performs self-oscillation.

Abstract: Provided is a surface emitting laser manufacturing method, etc., which reduces process damage occurring to a surface relief structure, enabling stable provision of a single transverse mode characteristic. Provided is a method including a surface relief structure for controlling a reflectance in a light emitting portion of an upper mirror, the surface relief structure including a stepped structure, includes: forming a resist pattern including a pattern for forming a mesa structure and a pattern for forming a stepped structure, on or above the upper mirror, and performing first-phase etching for etching the surface layer of the upper mirror to determine the horizontal position of the stepped structure; forming a current confining structure after the performing first-phase etching; and performing second-phase etching for further etching the area that the first-phase etching has been performed, to determine the depth position of the stepped structure, after the forming a current confining structure.

Abstract: A semiconductor laser device producing light having a TE-polarized component suitable for practical use (i.e., light having TE-polarized light intensity sufficiently high for practical use). A semiconductor laser device includes a GaAsP active layer, InGaP guide layers, and AlGaInP cladding layers. The GaAsP active layer emits light. The GaAsP active layer is interposed between the InGaP guide layers. The InGaP guide layers and GaAsP active layer are interposed between the AlGaInP cladding layers. Polarization ratio, which is a ratio of light intensity of TM-polarized light to light intensity of TE-polarized light, of the light produced by the semiconductor laser device is less than 2.3.

Abstract: Current channels, blocking areas, or strips in a semiconductor laser are used to channel injected current into the antinodal region of the optical standing wave present in the optical cavity, while restricting the current flow to the nodal regions. Previous devices injected current into both the nodal and antinodal regions of the wave, which is fed by the population inversion created in the active region by the injected electrons and holes, but inversion created in the nodal regions is lost to fluorescence or supports the creation of undesirable competing longitudinal modes, causing inefficiency. Directing current to the antinodal regions where the electric field is at its maximum causes a selected longitudinal mode to preferentially oscillate regardless of where the longitudinal mode lies with respect to the gain curve. In one embodiment, exacting fabrication of the Fabry-Perot cavity correlates the current channels to antinodal regions, vis-a vis current blocking areas, strips or segmented layers.

Abstract: A red laser portion and an infrared laser portion are integrated on an n-type GaAs substrate. A p-type cladding layer made of p-type AlGaInP in the red laser portion and a p-type cladding layer made of p-type AlGaInP in the infrared laser portion have a ridge stripe portion having a light emitting point. A current block layer made of SiNx is formed on both sides of each ridge stripe portion, and a strain relaxing layer made of ZrO2 is selectively formed on an outer side of each ridge stripe region on the current block layer. Provided that Tc is a thermal expansion coefficient of the p-type cladding layers, Tb is a thermal expansion coefficient of the current block layer, and Ts is a thermal expansion coefficient of the strain relaxing layer, the relation of Tb<Tc<Ts is satisfied.

Abstract: An photonic device, comprising one section of a material which is different from the material of another section such that the two sections present different optical birefringent index values. This causes a first set of polarization modes to move in a spectral space with a different velocity than a second set of polarization modes. A bias current, or voltage, is used for controlling the overall birefringence effect in the device. The biasing for controlling the birefringence effect is performed such the TE modes and the TM modes of the device are made to coincide in their respective spectral position. Thus the device is made insensitive, or presents substantially reduced sensitivity, to the polarization of any incoming optical signal.

Abstract: To provide a surface emitting laser device including a substrate; an optical resonator arranged on the substrate, the optical resonator including a lower multilayer reflector and an upper multilayer reflector; a strained active layer arranged in the resonator, the strained active layer having a multiple quantum well structure formed with a quantum well layer and a barrier layer; and a current confinement layer arranged on an upper side of the strained active layer, the current confinement layer including a selectively oxidized portion, where the current confinement layer is arranged at a position where a strain in the selectively oxidized portion influences the strained active layer.

Abstract: A nitride based semiconductor device includes: an n-type cladding layer; an n-type GaN based guide layer placed on the n-type cladding layer; an active layer placed on the n-type GaN based guide layer; a p-type GaN based guide layer placed on the active layer; an electron block layer placed on the p-type GaN based guide layer; a stress relaxation layer placed on the electron block layer; and a p-type cladding layer placed on the stress relaxation layer, and the nitride based semiconductor device alleviates the stress occurred under the influence of the electron block layer, does not affect light distribution by the electron block layer, reduces threshold current, can suppress the degradation of reliability, can suppress degradation of the emitting end surface of the laser beam, can improve the far field pattern, and is long lasting, and fabrication method of the device is also provided.

Abstract: A glaze encapsulated solid-state laser component. The novel laser component includes a core and a cladding of ceramic glaze disposed on a surface of the core. In an illustrative embodiment, the core is fabricated from a laser gain medium and the cladding material is a multi-oxide eutectic ceramic glaze having a refractivity slighter lower than the refractivity of the gain medium, such that the glaze layer forms a step-index refractivity interface cladding that can effectively suppress parasitic oscillations in the core gain medium. The glaze cladding can be applied by coating the core with the glaze and then firing the glaze coated core, or by fabricating pre-formed cladding strips from the ceramic glaze in a first firing cycle, mounting the pre-formed strips to the core, and then fusing the pre-formed strips to the core in a secondary firing cycle.

Abstract: A radiation-emitting semiconductor component has a high p-type conductivity. The semiconductor body of the component includes a substrate, preferably an SiC-based substrate, on which a plurality of GaN-based layers have been formed. The active region of these layers is arranged between at least one n-conducting layer and a p-conducting layer. The p-conducting layer is grown in tensile-stressed form. The p-doping that is used is preferably Mg.

Abstract: A III-nitride optoelectronic device comprising a light emitting diode (LED) or laser diode with a peak emission wavelength longer than 500 nm. The III-nitride device has a dislocation density, originating from interfaces between an indium containing well layer and barrier layers, less than 9×109 cm?2. The III-nitride device is grown with an interruption time, between growth of the well layer and barrier layers, of more than 1 minute.

Abstract: A laser diode capable of reducing a radiating angle ?? in the vertical direction, an optical pickup device, an optical disk apparatus, and optical communications equipment, all equipped with the laser diode which increases optical coupling efficiency. It has a first cladding layer of the first conductive type formed on a substrate, with an active layer on top of the first cladding layer and a second cladding layer of the second conductive type on top of the active layer. In at least the first or second cladding layer, it is formed of at least one optical guide layer having a higher refractive index than the first or second cladding layer and operating to expand a beam waist in the waveguide. This operation contributes to widening a region in which to shut up light, enabling a radiating angle ?? in the vertical direction to be reduced.

Abstract: Several methods are used in novel ways with newly identified and viable parameters to decrease the peak transition energies of the pseudomorphic InGaAs/GaAs heterostructures. These techniques, taken separately or in combination, suffice to permit operation of light emitting devices at wavelengths of 1.3 ?m or greater of light-emitting electro-optic devices. These methods or techniques, by example, include: (1) utilizing new superlattice structures having high In concentrations in the active region, (2) utilizing strain compensation to increase the usable layer thickness for quantum wells with appropriately high In concentrations, (3) utilizing appropriately small amounts of nitrogen (N) in the pseudomorphic InGaAsN/GaAs laser structure, and (4) use of nominal (111) oriented substrates to increase the usable layer thickness for quantum wells with appropriately high In concentrations.