1044results 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 discloses a distributed feedback laser and a preparation method thereof, and relates to the field of lasers. The preparation method of the distributed feedback laser comprises the following steps: forming a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer, an upper limiting layer, a grating layer, a grating buried layer, a corrosion stop layer, an InP cladding, a barrier gradient layer, a contact layer and a sacrificial layer on a substrate, wherein the sacrificial layer comprises an InP layer and an InGaAs layer which are stacked in sequence; etching to form a ridge waveguide structure; forming an insulating layer; removing the insulating layer in a preset area on the ridge waveguide structure to expose the sacrificial layer; wherein the side wall of the InGaAs layer is completely exposed, and the side wall of the InP layer is partially exposed; and etching to remove the InGaAs layer and the InP layer to form an upper electrode layer and a lower electrode layer. According to the invention, the reliability and the electro-optical conversion efficiency of the distributed feedback laser can be improved.

The invention provides a quantum well, a multi-quantum well epitaxial structure and a preparation method thereof, and belongs to the field of semiconductor lasers. The invention provides a quantum well which is of a multi-layer structure and comprises alternate quantum barrier layers and quantum well layers. The array substrate further comprises a gradient buffer layer. The adjacent quantum barrier layer and quantum well layer are combined through a gradient buffer layer; the bottom layer and the top layer in the multi-layer structure are quantum barrier layers; in a unit formed by the connected quantum barrier layer, gradual change buffer layer and quantum well layer, with the quantum barrier layer as the beginning and the adjacent quantum well layer as the end, the size of the gradual change buffer layer in the horizontal direction is gradually reduced, the emission wavelength of the gradual change buffer layer is gradually increased in the direction from beginning to end, and the emission wavelength of the gradual change buffer layer is gradually increased. The initial emission wavelength of the gradient buffer layer is consistent with the emission wavelength of the quantum barrier, and the final emission wavelength of the gradient buffer layer is smaller than the emission wavelength of the quantum well. The quantum well has a high carrier migration rate, a high refractive index and a high optical confinement factor.

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.

The gallium nitride-based semiconductor laser comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer which are sequentially arranged from bottom to top. According to the semiconductor laser element, the multi-vacancy electron phonon regulation and control layers of a multi-layer structure are arranged in the semiconductor laser element, and the electron affinity distribution characteristic and the polarization optical phonon energy distribution characteristic of each multi-vacancy electron phonon regulation and control layer are limited, so that single-vacancy, vacancy group and multi-vacancy regulation and control electron phonon structures are formed; the electron phonons are localized between the lower limiting layer and the lower waveguide layer, stokes frequency shift formed by photon energy difference between pump light and oscillation light is reduced, phonon vibration and phonon transport heat loss are reduced, the heat dissipation performance of a laser element is improved, thermal mismatch between epitaxial layers is improved, the thermal lens effect and stress birefringence effect of the laser are inhibited, and the laser efficiency is improved. The problems of laser beam distortion and depolarization are improved, and the laser beam quality factor is improved.

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 with a current modulation function and a preparation method, and relates to the field of semiconductor laser chips, and the semiconductor laser chip comprises a substrate layer, an n-type limiting layer, an n-type waveguide layer, a quantum well active region, a p-type waveguide layer, a first p-type limiting layer, a second p-type limiting layer and a contact layer which are sequentially stacked from bottom to top, the anti-reflection cavity surface and the high-reflection cavity surface are arranged on the two opposite sides of the second p-type limiting layer, the functional area is arranged between the anti-reflection cavity surface and the high-reflection cavity surface and comprises a current injection sub-area and a current blocking sub-area, the current injection sub-area is provided with a plurality of injection tips, the current blocking sub-area is provided with a plurality of blocking tips, and the injection tips and the blocking tips are arranged on the first p-type limiting layer. The injection tip is arranged between any two adjacent blocking tips; two grooves formed in the first p-type limiting layer penetrate through the second p-type limiting layer and the contact layer, and the two grooves are located in the two opposite sides of the current injection sub-region and the current blocking sub-region. According to the semiconductor laser chip, the light emitting power and the light beam quality of the semiconductor laser chip can be improved.

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.

A two-dimensional photonic crystal surface emitting laser includes an n-doped substrate, an n-doped cladding layer, an active layer, a photonic crystal layer, a p-doped cladding layer and a p-doped contact layer arranged in sequence from top to bottom. The photonic crystal layer includes a base material and a plurality of unit cells arranged periodically, each unit cell includes a first different-refractive index region, a second different-refractive index region and a third different-refractive index region that have a different refractive index from the base material. The surface emitting laser based on the photonic crystal structure may maintain single-mode operating characteristics of a device under a large mode field area, so that a high-power single-mode surface emitting laser may be achieved.

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.

Systems, devices, and methods are provided for all-optical reconfigurable activation devices for realizing various activations functions having normalized output power. The device and systems disclosed herein include an interferometer comprising a first branch formed of a first waveguide and a second branch formed of a second waveguide. A resonator cavity is coupled to the second first waveguide and at least one phase-shift mechanism is coupled to one of the second waveguide and the resonator cavity. The at least one phase-shift mechanism is configured to control biases of the interferometer to achieve a desired activation function at an output of the interferometer, and an optical amplification mechanism is coupled to the output of the interferometer and configured to add optical gain to the desired activation function.

An optical semiconductor device of the present disclosure has an effective refractive index nc, a wavelength λ, and an anti-reflection film formed of i coating films. The thickness of the kth coating film (1≤k≤i) is set at a value other than λ / 2 / nk. The refractive index of one or more coating films is greater than a refractive index nf which is the square root of nc. The refractive index of one or more coating films is smaller than nf. A characteristic matrix of the multilayer coating film is equal to that of a single-layer coating film of which a refractive index is nf and a thickness df is λ / 4 / nf. The thicknesses of (i−3) coating films are set in advance. The thicknesses of the remaining three coating films are determined by solutions of three simultaneous equations derived from the characteristic matrix of the multilayer coating film.

The invention discloses a multi-wavelength high-polarization-degree straight-cavity surface emitting laser which is structurally composed of a plurality of connecting layers and comprises a lower electrode layer, a substrate layer, a lower DBR layer, a lower spacing layer, a lower waveguide layer, a quantum well layer, an upper waveguide layer, an upper spacing layer, an upper DBR layer and an upper electrode layer. The upper waveguide layer comprises a plurality of strip-shaped waveguides which are arranged in parallel in the same plane and have different widths, and filling materials filled among the plurality of strip-shaped waveguides. And the width change of the plurality of strip-shaped waveguides is an arithmetic progression of periodic circulation. Through the design of the upper waveguide layer structure, the growth speed difference can be realized, the thickness difference of the spacing layer is accurately controlled, and the laser wavelength is adjusted. Compared with a traditional method, high cost and technical problems caused by using a sub-wavelength grating are avoided.

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 provides an LED which is applied to the field of LEDs or the field of optical communication. The LED includes a P-type semiconductor layer, an active layer, and an N-type semiconductor layer. The active layer is located between the P-type semiconductor layer and the N-type semiconductor layer. The active layer comprises M barrier layers and M-1 well layers. The barrier layers and the well layers are alternately distributed. M is an integer greater than 1. And each barrier layer in the M barrier layers is a P-type doped layer. The sum of the doping concentration of N first barrier layers, close to the N-type semiconductor layer, in the M barrier layers is larger than the sum of the doping concentration of N second barrier layers, close to the P-type semiconductor layer, in the M barrier layers. When M is an even number, N = M / 2; and when M is an odd number, N = M / 2-1 / 2. In the technical scheme provided by the invention, the bandwidth of the LED can be improved by controlling the P-type doping concentration of the M barrier layers, so that the optical communication efficiency is improved.

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 element with a spin polarization sub-layer. The semiconductor laser element comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer which are sequentially arranged from bottom to top. According to the semiconductor laser element, the spin polarization sub-layers of a multi-layer structure are arranged between the upper limiting layer and the upper waveguide layer in the semiconductor laser element, and the electron mobility distribution characteristic and the piezoelectric polarization coefficient distribution characteristic of each spin polarization sub-layer are limited. Specific electron mobility distribution and piezoelectric polarization coefficient distribution of the spin polarization sub-layer form an asymmetric discrete potential barrier, lattice distortion structure polarization is modulated, charge dipole momentum net accumulation is increased, the piezoelectric polarization effect of the active layer is regulated and controlled, the quantum restriction effect is suppressed, energy band inclination of the active layer is reduced, and hole injection band order is reduced. The overlapping probability of the electron hole wave function is improved, and the internal quantum efficiency is improved.

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.

The invention relates to the technical field of spontaneous emission light sources, in particular to an integrated amplified spontaneous emission light source based on an erbium-doped waveguide, which comprises a pump laser, a wavelength division multiplexer, the erbium-doped waveguide, a waveguide reflecting region, a waveguide optical isolator and a waveguide filter, and is characterized in that the wavelength division multiplexer is provided with an input end, a first output end and a second output end; the pump laser is connected with the input end of the wavelength division multiplexer, the second output end of the wavelength division multiplexer is connected with the waveguide reflection area, the first output end of the wavelength division multiplexer is connected to the input end of the erbium-doped waveguide, the output end of the erbium-doped waveguide is connected to the input end of the waveguide optical isolator, and the output end of the waveguide optical isolator is connected with the waveguide filter; the size of the light source is greatly reduced through the integrated waveguide design, and the performance of the light source is guaranteed under the condition that the size of the light source is greatly reduced.

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.

The invention provides a broadband tunable light emitting chip based on an asymmetric multi-quantum well technology and a preparation method, the tunable light emitting chip comprises a plurality of laser units distributed in columns, and each column of laser units comprises a plurality of lasers connected in series; the laser units achieve single-waveguide laser output through cascade Y waveguide combination, each laser comprises an asymmetric multi-quantum well layer and a grating layer, the thickness of each quantum well is gradually decreased from top to bottom, and a grating is located on the surface of the upper limiting layer. The tunable lasers connected in series and in parallel are adopted, and single-waveguide laser output is achieved through cascade Y waveguide combination; the asymmetric multiple quantum wells are arranged, so that the overall tunable range of the laser can be widened; a sampling grating is manufactured through a reconstruction equivalent chirp technology to select a lasing wavelength, and pi phase shift is introduced to carry out phase matching so as to ensure single wavelength output; according to the invention, gains can be provided for a plurality of laser units, the density of monolithic integration is improved, the transmission capacity is increased, and the single-mode yield is improved.