767results about "Laser active region structure" patented technology

Tailored doping of barrier layers enables balancing of the radiative recombination among the multiple-quantum-wells in III-Nitride light-emitting diodes. This tailored doping enables more symmetric carrier transport and uniform carrier distribution which help to reduce electron leakage and thus reduce the efficiency droop in high-power III-Nitride LEDs. Mitigation of the efficiency droop in III-Nitride LEDs may enable the pervasive market penetration of solid-state-lighting technologies in high-power lighting and illumination.

The invention provides a patterned photonic crystal laser and a preparation method thereof, the laser comprises a substrate, and a first mask layer, a photonic crystal layer and a second mask layer which are sequentially deposited on the substrate, a light emitting area is etched in the central area of the second mask layer, and transparent conductive layers are deposited on the surface of the second mask layer and the light emitting area; a p-annular electrode is arranged on the surface of the transparent conductive layer on the second mask layer, and an n-annular electrode is arranged below the substrate; the photonic crystal layer is composed of a nanorod array and a polymer filled in gaps of nanorods; holes distributed in a patterned array are etched in the surface of the first mask layer, and nanorods are epitaxially grown in hole areas; the nanorod is formed by sequentially depositing a substrate contact layer, a first waveguide layer, a multi-quantum well layer, a second waveguide layer, a coating layer and a component gradient layer. According to the invention, through collaborative design optimization of all the layers, emission of laser with specific wavelength and preparation of a laser emitting laser with single longitudinal mode, narrow linewidth and stable wavelength are realized.

The invention relates to a method for improving epitaxial growth quality of a tunnel junction cascade semiconductor laser. The invention innovatively provides a strain superlattice gradient repair technology. By designing a low-temperature low-speed nucleation-high-temperature high-speed epitaxy composite growth mode, a periodic superlattice buffer layer is introduced to a tunnel junction interface. Wherein lattice strain relaxation is achieved at the rate of 0.5-2 / s in the low-temperature stage, defect coverage is completed at the rate of 4-8 / s in the high-temperature stage, and dislocation line bending is terminated on a superlattice interface through thermodynamic regulation and control. Compared with the traditional process, the scheme can obviously improve the crystal quality, and does not increase the specific contact resistance of the tunnel junction interface.

A method of fabricating an optoelectronic component, performed on a multi-layered wafer disposed on a substrate. The method comprises the steps of: etching the multi-layered wafer, thereby defining a slab and a multi-layered ridge, the slab having an upper surface below the ridge and being located between the multi-layered ridge and the substrate; selectively epitaxially growing a III-V semiconductor cladding adjacent to a first and second sidewall of the ridge, the cladding layer extending from the upper surface of the slab along the first and second sidewalls, and thereby cladding an optically active waveguide within the multi-layered ridge; and providing a first and second electrical contact, which electrically connect to a layer of the multi-layered ridge and the slab respectively.

High-power, integrated optical amplifiers are described in which gain waveguides of the amplifiers are designed to improve power performance by reducing power saturation effects in the amplifier. The gain waveguides can change, in at least one aspect, along the length of the gain waveguide to reduce gain saturation. Multi-mode optical beams and / or multi-stage amplification can also be employed to reduce gain saturation.

The invention provides a semiconductor laser chip and a preparation method, and belongs to the technical field of semiconductor laser chip preparation, and the semiconductor laser chip comprises an N-surface metal, a substrate, an N-type limiting layer, an N-type waveguide layer, a tensile strain quantum well, a P-type waveguide layer, a P-type limiting layer, an ohmic contact layer, a SiO2 insulating layer, a first P-surface metal layer and a second P-surface metal layer which are sequentially arranged from bottom to top. Waveguide grooves are symmetrically formed in the two sides of the ohmic contact layer and penetrate through the ohmic contact layer, the bottoms of the grooves sink to the P-type limiting layer but do not exceed the P-type limiting layer, and a ridge waveguide is formed between the two grooves. The depth of the waveguide groove is of a stepped structure in the longitudinal direction, the depth of the area close to the cavity surface is increased to the N-type waveguide layer, the area completely covers the SiO2 insulating layer and the first layer of P-surface metal, but no second layer of P-surface metal exists, and the longitudinal stepped structure is formed. Through the design of the tensile strain quantum well and the stepped waveguide groove, cavity surface tensile strain release is realized, light absorption is reduced, and the reliability and the service life of the chip are improved.

A continuous-wave perovskite polariton laser device, including an optical microcavity, a spacer layer, and a gain medium. The gain medium is a perovskite material or a composite material containing perovskite, in a form of thin film, microcrystal, phosphor, nanocrystal, quantum dot, or single crystal. The perovskite gain medium is prepared by solution process or vacuum deposition technique, and is combined with an optical resonator. By exploiting the strong interaction between excitons and photons, a steady-state exciton-polariton condensation is formed, enabling the generation of continuous-wave polariton laser emission with a low threshold. The laser device can achieve low-threshold continuous-wave or pulsed lasing emission at room temperature under various light sources pumping or electrical excitation. Its threshold is 1 to 3 orders of magnitude lower than that of conventional semiconductor lasers, with an optimized threshold as low as 0.1 to 1 W / cm2, representing a novel ultralow-power coherent light source technology.

The invention, which relates to the technical field of the semiconductor laser chip, discloses a wide-temperature working high-power DFB semiconductor laser chip comprising a P-InGaAsP lower waveguide layer, an InGaAsP strain multiple quantum channel, an N-InGaAsP upper waveguide layer, an InAlAs-InP superlattice barrier layer, an N-InP spacing layer 1, an N-InGaAsP corrosion stop layer, an N-InP spacing layer 2, an N-InGaAsP grating layer, and an N-InP grating cover layer. According to the wide-temperature working high-power DFB semiconductor laser chip, a laser material structure is epitaxially grown on a P-InP substrate; a P-InP substrate is adopted, so that large-area back ohmic contact effectively reduces P-type series resistance of a device, and the problem of high heating of a traditional high-power laser is effectively solved; then, an InGaAsP strain compensation quantum well is adopted as a gain region, and wide-temperature single-mode work is realized by utilizing the advantage that an InGaAsP gain spectrum is insensitive to temperature; and the InAlAs-InP two-dimensional superlattice barrier structure is adopted to realize transverse and lateral limitation of carriers, so that the limiting efficiency of the carriers in a gain region is effectively improved, and the problem of low energy band difference of an InGaAsP conduction band is effectively solved.

The invention provides an ultrahigh strain material component and thickness control method for a quantum cascade laser, and relates to the technical field of semiconductor lasers. The control method is based on a strain compensation calibration method, a first superlattice layer and a second superlattice layer which are the same in thickness are constructed, a strain balance superlattice is formed, it is guaranteed that the whole epitaxial layer is free of strain relative to a substrate, the problem that the growth thickness of a large-strain material is small is solved, the peak position accuracy and the peak intensity during XRD testing are further improved, and the test accuracy is improved. And the half-peak width is narrow, so that the accuracy of the components of the backstepping material is improved.

The invention provides a topological posture single photon source device and a quantum light source, and relates to the technical field of topological quantum light sources. The topological state single photon source device comprises a GaAs layer; the SiO2 / Au structure comprises a SiO2 layer and an Au layer, and is positioned below the GaAs layer to serve as a reflecting mirror for inhibiting backward photon leakage; the topological state microcavity is processed and formed on the GaAs layer; and the quantum dots grow in the GaAs layer and are coupled with the topological posture of the topological posture microcavity to generate a topological posture single photon source. According to the invention, the coupling efficiency of the quantum dots and the microcavity is effectively improved by using the mode volume with a relatively large topological posture, the bottleneck that the coupling probability is low due to the limited volume of a traditional mode is broken through, and a better scheme is provided for realizing the interaction of high-efficiency light and substances.

The invention discloses a preparation method and a structure of a novel electro-absorption modulated laser, and the method comprises the steps: symmetrically dividing a substrate into a double-end modulation region, a gain region, a grating region and a phase region, manufacturing a first mask pattern on the surface of the gain region, growing an active layer containing a quantum well structure in a mask gap through a selective region epitaxy technology, forbidden band red shift of the gain region is realized; manufacturing a mask covering the gain region and the modulation region, and etching a non-functional region to expose the substrate; a passive material with a wider band gap is grown in the exposed substrate area in a butt joint mode, and a photon limiting structure is formed; manufacturing a sampling grating through electron beam direct writing, growing a cladding layer and a contact layer, and etching an inverted table shallow ridge waveguide; and finally, etching an electrical isolation trench and manufacturing a double-sided electrode to complete device integration. Through the selective area epitaxial growth technology, active materials with two forbidden bandwidths of the gain area and the modulation area are achieved through one-time epitaxial growth, and a solution with extremely low cost is provided for the wavelength tunable electro-absorption modulated laser.

According to one embodiment, an optical element includes a first member. The first member includes a first region along a first plane. The first region includes a plurality of first structures. The plurality of first structures are arranged along a first direction at a first pitch and along a second direction at a second pitch. The first direction is along the first plane. The second direction is along the first plane and crosses the first direction. The first pitch is longer than the second pitch. A first length of the first region along the first direction is longer than a second length of the first region along the second direction.

The invention provides a micro-disk structure semiconductor laser and a preparation method, and belongs to the technical field of semiconductor lasers. The high-concentration Zn-doped p-GaAs multi-quantum-well multi-quantum-well light-emitting diode comprises a SiO2 barrier layer, an n-GaAs substrate with the thickness of 100 microns, an n-GaAs contact layer with the thickness of 100 nm, a Si-doped n-AlGaInP limiting layer with the thickness of 200 nm, an n-AlGaInP waveguide layer with the thickness of 400 nm, a first GaInP / AlGaInP multi-quantum-well layer, a GaAs barrier layer, a second GaInP / AlGaInP multi-quantum-well layer, an undoped p-AlGaAs waveguide layer with the thickness of 150 nm, a Zn-doped p-AlGaInP limiting layer with the thickness of 200 nm and a high-concentration Zn-doped p-GaAs contact layer with the thickness of 100 nm. By controlling the thickness and the doping concentration of each layer, efficient limitation and injection of carriers are realized; due to the design of the double multi-quantum well layer and the barrier layer, the device can realize stable lasing in two wavebands of 808nm and 650nm; the undoped waveguide layer effectively reduces the optical loss, prolongs the photon lifetime, and improves the laser output efficiency. And the quantum efficiency and the temperature stability of the device are improved.

A laser diode includes an active region, confinement layers, and cladding layers. The active region includes one or more active layers that each exert a first strain in a first direction and one or more strain compensating layer that each exert a second strain in a second direction that is opposite the first direction. The confinement layers bound the active region. The cladding layers bound the confinement layers. In some embodiments, each active layer comprises InAs quantum dots in a InrGa1-rAs quantum well, where 0≤r≤1; and each strain compensating layer comprises a GaAs1-sPs layer, where 0<s≤1. The confinement layers may each comprise a (AlzGa1-z)wIn1-wP layer, where 0<w<1 and 0≤z<1. The cladding layers may each comprise a (AlyGa1-y)xIn1-xP layer, where 0<x<1 and 0≤y<1.

A light emitting device comprising a germanium first layer; a nucleation layer; a buffer layer comprising a III-V composition; and an active layer. The sum product of As concentration and layer thickness in each of the layers is less than 20%. This enables the devices to be fabricated in an environment which must be free, or substantially free, of arsenic.

The invention provides a semiconductor laser and a preparation method thereof. The preparation method comprises the following steps: forming a lower limiting layer on one side of a semiconductor substrate layer along a first direction; a ridge-shaped structure is formed on the side, away from the semiconductor substrate layer, of a part of the lower limiting layer, the ridge-shaped structure comprises a lower waveguide layer, an active layer, an upper waveguide layer, a grating layer and a cover layer which are sequentially stacked in the first direction, and the cover layer is located on the side, away from the upper waveguide layer, of the grating layer; an insulating epitaxial layer is formed on the side, away from the semiconductor substrate layer, of the lower limiting layer, the insulating epitaxial layer is located on the side, away from the semiconductor substrate layer, of the ridge-shaped structure and on the two sides, in the slow axis direction, of the ridge-shaped structure, and the thermal conductivity of the insulating epitaxial layer is larger than that of the active layer; an opening is formed in the insulating epitaxial layer, the opening exposes the cover layer, and the size of the opening in the slow axis direction is larger than that of the ridge-shaped structure in the slow axis direction; an upper confinement layer is formed in the opening.

Systems and methods are provided for patterned embedding on narrow stripe single mode transverse lasers. An example narrow stripe optical emitter device may include an active region containing semiconductor material, a first embedding region located on a first end of the narrow stripe optical emitter device and containing a first embedding material, and a second embedding region located on a second end of the narrow stripe optical emitter device and containing a second embedding material. The active region may include a ridge running between the first end and the second end of the narrow stripe optical emitter device. The first embedding material may be different from the second embedding material with respect to one or more characteristics. The one or more characteristics may include compressive strain related parameters and / or attributes.

Systems and methods are provided for refractive index engineering for brightness enhancement and kink suppression in optical emitter devices. An example optical emitter device may include a first region that includes a first semiconductor material, an active region located on the first region, with the active region including a pumped active region between a front end and a back end of the optical emitter device, and a plurality of loss structures arranged along at least a portion of at least one side of the pumped active region. The plurality of loss structures may be arranged between the front end and the back end of the optical emitter device. The plurality of loss structures may include two or more continuous etched lines. The plurality of loss structures may include two or more discontinuous etched features.

[Task] A semiconductor laser element with reduced light loss is provided. [Solution] A semiconductor laser element emits ultraviolet light and includes an n-side cladding layer, an n-side guide layer, an active layer, a p-side guide layer, and a p-side cladding layer, each made of a nitride semiconductor, in this order upwards. The semiconductor laser element includes a first surface and a ridge portion protruding upwards from the first surface. The first surface is located at the top with respect to a lower end of the p-side guide layer and at the bottom with respect to an upper end of the p-side guide layer. A thickness of the n-side guide layer is thinner than a thickness of the n-side cladding layer. An Al composition ratio of the n-side guide layer is smaller than an Al composition ratio of the n-side cladding layer.a thickness of the p-side guide layer is thinner than a thickness of the p-side cladding layer and thinner than the thickness of the n-side guide layer, and an Al composition ratio of the p-side guide layer is smaller than an Al composition ratio of the p-side cladding layer.,

The invention provides a multi-junction cascade photonic crystal surface emitting laser and a preparation method thereof. The multi-junction cascade photonic crystal surface emitting laser comprises a substrate; the three-dimensional photonic crystal structure is arranged on the substrate, the three-dimensional photonic crystal structure comprises a longitudinal periodic structure formed by a plurality of laminated structures which are sequentially stacked in the vertical direction of the substrate, each laminated structure comprises an active layer and a photonic crystal layer, and the photonic crystal layer provides optical feedback for the active layer to form optical resonance; a transverse periodic structure is formed in each photonic crystal layer; and the plurality of tunnel junctions are arranged between the two adjacent laminated structures and are used for electrically connecting the two adjacent laminated structures.

Devices, systems and methods for operating and using an optically quenchable carbon-doped gallium nitride photoconductive semiconductor switch (PCSS) are described. An example method includes illuminating a carbon-doped gallium nitride material of the photoconductive semiconductor switch with a first laser light within a first range of wavelengths to trigger the photoconductive semiconductor switch to a conductive state, turning off or blocking the first laser light, and illuminating the carbon-doped gallium nitride material with a second laser light within a second range of wavelengths to trigger the photoconductive semiconductor switch to an insulating state. In this example, the first range of wavelengths comprises an ultraviolet (UV) or a blue wavelength range, the second range of wavelengths comprises an infrared (IR) or a red wavelength range, and switching from the conductive state to the insulating state occurs within a sub-nanosecond range.

The invention provides a high-power external cavity tunable quantum cascade laser output module. The high-power external cavity tunable quantum cascade laser output module comprises a first lens, a first half-wave plate and a first mid-infrared grid polaroid which are sequentially arranged along a light path of a first laser; a second lens, a second half-wave plate, a second mid-infrared grid polarizer and a third half-wave plate are sequentially arranged along the light path of the second laser; emergent light of the first mid-infrared grid polaroid and the third half-wave plate is converged on different surfaces of the third mid-infrared grid polaroid, the first blazed grating is arranged on a reflection light path of the first mid-infrared grid polaroid, and the second blazed grating is arranged on a reflection light path of the second mid-infrared grid polaroid. According to the invention, the problems of wavelength locking and low polarization beam combination efficiency caused by insufficient polarization state of the quantum cascade laser can be effectively solved, narrow linewidth output and wavelength tuning of the quantum cascade laser can be realized, and even high-power dual-wavelength tunable output can be realized through polarization beam combination structure expansion.

Provided is a semiconductor laser diode including multiple active layers and a grating layer. The semiconductor laser diode includes two (or more than two) active layers, a grating layer, and a tunnel junction. The grating layer and the tunnel junction are provided between the two active layers. The tunnel junction is electrically connected to the two active layers, and the two active layers share and are optically coupled to the grating layer, thereby improving the external quantum efficiency and slope efficiency of the semiconductor laser diode.

The invention discloses an in-plane heterogeneous photonic crystal quantum cascade laser. The in-plane heterogeneous photonic crystal quantum cascade laser comprises a back metal electrode, a front metal electrode and an epitaxial wafer located between the back metal electrode and the front metal electrode. Wherein a photonic crystal layer is arranged between the epitaxial wafer and the front metal electrode; wherein the photonic crystal layer is composed of first-order photonic crystals, symmetrical bilattices and second-order photonic crystals which are periodically arranged and are sequentially symmetrical from outside to inside. The problems of low modal selectivity, low coupling efficiency and the like of the existing wide ridge emission QCL are solved, and a new thought is provided for researching the large-area QCL with high power and light beam quality.

A quantum-cascade laser element includes: a semiconductor substrate; a semiconductor mesa formed on the semiconductor substrate to include an active layer having a quantum-cascade structure and to extend along a light waveguide direction; an embedding layer formed to interpose the semiconductor mesa along a width direction of the semiconductor substrate; a cladding layer formed over the semiconductor mesa and over the embedding layer; and a metal layer formed on the cladding layer. A pair of groove portions extending along the light waveguide direction are formed in a surface on an opposite side of the cladding layer from the semiconductor substrate. The pair of groove portions are disposed in two respective outer regions when the cladding layer is equally divided into four regions in the width direction of the semiconductor substrate. The metal layer enters the pair of groove portions.

A vertical cavity surface emitting semiconductor laser (VCSEL) has a semiconductor multilayer structure with an optical resonator (12) consisting of semiconductor layers, the optical resonator (12) has a first Bragg mirror (16), a second Bragg mirror (18), and an active region (20) for generating laser radiation between the first Bragg mirror (16) and the second Bragg mirror (18). The active region (20) has a plurality of active layers (22, 24, 40) having a first active layer and at least one second active layer (22, 24), the second active layer (24) being the last active layer located before the second Bragg reflector (18). A first oxide barrier (26) and a first tunnel diode (30) for limiting a current are arranged between the first active layer (22) and the second active layer (24), and a second oxide barrier (32) is arranged on a side of the second active layer (24) facing away from the first active layer (22). A second tunnel diode (34) is arranged on the side of the second active layer (24) facing away from the first active layer (22). The invention also relates to a method for manufacturing the VCSEL.

Example methods, compositions and structures are presented whereby sub-10-nm-thick strain-relieving Si1-xGex layers can be realized by Ge ion implantation, into, and selective oxidation of, Si(111) wafers. The resulting Ge-rich layers are fully strain relaxed via a network of misfit dislocations at the Si / Si1-xGe, interface, which do not propagate through the Si1-xGex film. The dislocation network has been found to coincide with a periodic variation in the composition at the Si / Si1-xGex interface and is believed to result from the defect-medicated diffusion of Si atoms from the Si substrate through the Si1-xGex layer to the above SiO2 layer. The epitaxial growth of GaAs on such ultra-thin substrates is demonstrated, presenting a promising approach for solving the long-standing challenge of local, monolithic integration of III-V optoelectronics on the Si platform.

A distributed feedback plus reflection (DFB+R) laser includes an active section, a passive section, a low reflection (LR) mirror, and an etalon. The active section includes a distributed feedback (DFB) grating and is configured to operate in a lasing mode. The passive section is coupled end to end with the active section. The LR mirror is formed on or in the passive section. The etalon includes a portion of the DFB grating, the passive section, and the LR mirror. The lasing mode of the active section is aligned to a long wavelength edge of a reflection peak of the etalon.

The invention provides a laser chip with a transverse carrier expansion superlattice and a preparation method, and relates to the technical field of semiconductor lasers. The chip sequentially comprises an N-type ohmic electrode, a substrate, a buffer layer, an N-type limiting layer, an N-type waveguide layer, an active layer, a P-type waveguide layer, a P-type limiting layer, an ohmic contact layer and a P-type ohmic electrode. A first superlattice layer is inserted into the two sides of the P-type waveguide layer, wherein the first superlattice layer is formed by alternately overlapping an undoped and narrow-band-gap Al < x > < 7 > In < y > < 7 > Ga < 1-x > < 7-y > As layer and a P-type doped and wide-band-gap Al < x > < 8 > In < y > < 8 > Ga < 1-x > < 8-y > As layer. A second superlattice layer is inserted into the two sides of the P-type limiting layer, wherein the second superlattice layer is formed by alternately overlapping an undoped Al < x > < 10 > In < y > < 10 > Ga < 1-x > < 10-y > As layer with a narrow band gap and a P-type doped Al < x > < 11 > In < y > < 11 > Ga < 1-x > < 11-y > As layer with a wide band gap. The chip utilizes the first superlattice layer and the second superlattice layer to promote holes at two sides of a device to migrate and transport from two sides of the chip to the middle in the undoped narrow-band gap layer, large optical loss is not caused, high electro-optical conversion efficiency is ensured, the intensity of a fundamental mode is improved, and a high-order mode is inhibited.

The disclosure provides a laser, a preparation method of the laser and an optical module, and relates to the technical field of optical elements, so as to meet the demand of the optical module for high-power lasers. The laser comprises the following steps: growing an etching auxiliary layer on the surface of a wafer body of the laser, the longitudinal etching rate of the wafer body is greater than the transverse etching rate of the wafer body, the transverse etching rate of the etching auxiliary layer is greater than the transverse etching rate of the wafer body, and the wafer body comprises a quantum well layer; forming a mask layer above the etching auxiliary layer, and pre-treating the mask layer to form a BH pattern; etching the BH pattern, so that the top of the wafer body is etched into a BH mesa, the etching depth is below the quantum well layer, and the etching depth is below the quantum well layer; growing a current blocking layer on both sides of the BH mesa; removing the mask layer and the etching auxiliary layer; and forming a P-InP layer on the top of the BH mesa and the current blocking layer.