92 results about "Slope efficiency" patented technology

Disclosed is a semiconductor laser, from bottom to top, comprising: a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer, and an upper limiting layer. The lower limiting layer is composed of at least one of AllnGaN, AllnN, AlGaN, InN, AlN, InGaN, and GaN. A thickness of the lower limiting layer is denoted as x, and 10 angstroms≤x≤90,000 angstroms. The lower limiting layer includes a first lower limiting layer, a second lower limiting layer, and a third lower limiting layer. The lower limiting layer forms an electron saving structure and a stress regulating structure to regulate a carrier distribution and a stress distribution of the active layer, thereby reducing a threshold current and improving a slope efficiency of the laser.

The utility model relates to the technical field of lasers, and discloses a high-slope-efficiency surface grating surface emitting laser which comprises a substrate, a lower waveguide layer, an active layer and an upper waveguide layer from bottom to top along the cross section. A ridge-shaped waveguide is formed in the middle area of the uppermost layer of the upper waveguide layer, and a Bragg grating is etched on the surface of the ridge-shaped waveguide; the Bragg grating comprises a section of second-order grating located in the middle and two sections of first-order gratings located at the two ends; a lambda / 4 phase shift is arranged in the second-order grating; the lambda / 4 phase shift is located in an etching area or a non-etching area of the first-order grating closest to the second-order grating; when the lambda / 4 phase shift is located in the etching region of the first-order grating closest to the second-order grating, the upward diffraction light power of the second-order grating is maximum, and the downward diffraction light power is minimum; when the lambda / 4 phase shift is located in the non-etching area of the first-order grating closest to the second-order grating, the upward diffraction light power of the second-order grating is minimum, and the downward diffraction light power of the second-order grating is maximum. According to the invention, high-slope efficiency lasing can be realized.

The invention relates to the technical field of aging test, and discloses a laser chip accelerated aging test method, which comprises the following steps: synchronously measuring the optical power, the threshold current, the slope efficiency and the emergent wavelength of a laser chip in an accelerated aging environment to obtain a time sequence data matrix; performing double sparse dictionary decomposition on the time series data matrix to obtain a normal feature coefficient and a degradation feature coefficient; calculating a target characteristic value of the time-varying covariance matrix based on the degradation characteristic coefficient, and generating a dynamic characteristic value sequence and a corresponding degradation stage identifier according to the target characteristic value; and based on the degradation stage identifier, inputting the dynamic characteristic value sequence into a life prediction model for life prediction, and obtaining the remaining service life. The method can accurately capture the nonlinear characteristic and the time evolution mode of the laser chip degradation process, automatically identify the time period characteristic which contributes to life prediction, and improve the service life of the laser chip. And the accelerated aging test accuracy of the laser chip is improved.

The invention relates to a quantum cascade laser with a cylindrical waveguide and a preparation method thereof, and belongs to the field of photoelectron, the quantum cascade laser comprises a laminated structure, the laminated structure is provided with two waveguide grooves, a ridge waveguide is formed between the two waveguide grooves, the waveguide grooves are hyperbolic, and the ridge waveguide is cylindrical; the bottom and side wall areas of the waveguide groove are subjected to mechanochemical grinding treatment and filled with InP: Fe, then mechanochemical grinding is carried out again, and then an insulating film layer material is evaporated; due to the unique cylindrical shape of the ridge waveguide, the photon density can be effectively improved, and the output characteristic of laser is optimized; and meanwhile, the mode distribution of light can be better controlled, and excellent laser characteristics are realized by utilizing optical reflection and interference effects. According to the invention, before secondary epitaxy, a mechanochemical grinding method is adopted to carry out surface treatment on the double channels, so that waveguide loss after secondary epitaxy of InP: Fe can be effectively reduced, the threshold current density is further reduced, and the output power and the slope efficiency are increased.

The utility model relates to the technical field of semiconductor photoelectric devices, in particular to a semiconductor laser chip, which comprises a substrate and an epitaxial layer, the section of the epitaxial layer along the laser emitting direction is a first end face, the section of the epitaxial layer opposite to the laser emitting direction is a second end face, the first end face is provided with an antireflection film layer, and the second end face is provided with a second antireflection film layer. The second end face is provided with a high-reflection film layer, and the reflectivity of the antireflection film layer is smaller than that of the high-reflection film layer; the refractive index of the epitaxial layer is greater than or equal to that of the antireflection film layer; the refractive index of the epitaxial layer is larger than or equal to that of the high-reflection film layer. According to the utility model, by designing the refractive index and the reflectivity of the antireflection film layer and the high-reflection film layer, the laser modulus of the optical waveguide layer is reduced, stimulated radiation is accelerated to exceed spontaneous radiation, the threshold current density of the laser is reduced, and the slope efficiency is improved; meanwhile, light field distribution of the optical waveguide is optimized, and light absorption loss and waveguide loss are reduced.

The invention discloses an asymmetric quantum barrier semiconductor laser and application thereof, and the asymmetric quantum barrier semiconductor laser comprises an active region, two sides of the active region are provided with an N-side quantum barrier region and a P-side quantum barrier region which are asymmetric, and the N-side quantum barrier region and the P-side quantum barrier region are made of the same semiconductor material. The N-side quantum barrier region and the P-side quantum barrier region simultaneously regulate and control the carrier limiting capability and the light field distribution of the laser; the N-side quantum barrier region and the P-side quantum barrier region can have different thicknesses and can also have different material component distribution forms or different material component sizes, and at least one physical parameter of the thicknesses, the material component distribution forms and the material component sizes of the N-side quantum barrier region and the P-side quantum barrier region is different. According to the semiconductor laser and the application thereof provided by the invention, the limiting capability of a quantum barrier on current carriers can be improved, the slope efficiency of the semiconductor laser is improved, and then the electro-optical conversion efficiency and the output power of the semiconductor laser are improved; in addition, the light field regulation freedom degree of the laser can be increased, the large near-field size can be obtained under the condition that the thin epitaxial thickness is guaranteed, and the electro-optical conversion efficiency of the semiconductor laser is further improved.

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 relates to the technical field of semiconductor photoelectric devices, and particularly discloses a gallium nitride-based semiconductor laser element with a carrier concentration matching layer. The gallium nitride-based semiconductor laser element with the carrier concentration matching layer sequentially comprises a substrate, a lower coating layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper coating layer from bottom to top, and the carrier concentration matching layer is arranged between the upper waveguide layer and the upper coating layer; according to the gallium nitride-based semiconductor laser element with the carrier concentration matching layer, by regulating and controlling the peak electron drift rate interface steep degree and the transverse sound velocity interface steep degree of the interface between the carrier concentration matching layer and the active layer and the interface between the carrier concentration matching layer and the upper coating layer, the valence band order of the laser is reduced, and the hole injection efficiency and the hole transport efficiency are improved; and the carrier injection uniformity and the laser gain uniformity are improved, so that the slope efficiency, the optical power and the photoelectric conversion efficiency of the laser are improved, the power consumption is reduced, and the service life is prolonged.

The present invention discloses a semiconductor laser comprising: a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, and an upper confinement layer, arranged in order from bottom to top; the active layer comprising a well layer and a barrier layer; the electron effective mass of the well layer of the active layer being smaller than the electron effective mass of the barrier layer, the spontaneous polarization coefficient of the well layer of the active layer being smaller than the spontaneous polarization coefficient of the barrier layer, and the bandgap width of the well layer of the active layer being smaller than the bandgap width of the barrier layer. The present invention can suppress InN phase separation, segregation, and composition fluctuation in high-In content semiconductor lasers, effectively improve the crystal quality and interface quality of the active layer, effectively enhance the electron-hole recombination efficiency of the active layer, and effectively reduce defects and non-radiative recombination centers, thereby effectively improving the slope efficiency of green lasers.

The application belongs to the technical field of laser materials, and relates to a holmium-praseodymium-scandium doped composite calcium fluoride single crystal as well as a preparation method and application thereof. 0.01 Pr x Sc y Ca 0.99‑x‑y F 2.01+x+y , wherein 0.005 <= x <= 0.015, 0.005 <= y <= 0.05; the crystal is obtained by growing the crystal in a vacuum environment through a temperature gradient method. Compared with the prior art, the application can realize high-efficiency laser output in a 2-3 mu m mid-infrared wave band, the grown crystal has the characteristics of high thermal conductivity, high chemical stability, high transmittance and high quality, and has the advantages of high gain bandwidth, high gain cross section, high power and high slope efficiency in the mid-infrared wave band, and has significant advantages in the fields of environmental monitoring, industrial processing, national defense and safety.

This invention discloses a ytterbium-doped fiber preform, a ytterbium-doped active fiber, and their preparation method. First, a quartz deposition tube with a porous core layer deposited on its inner surface is prepared using the MCVD process. After heating and breaking off one end of the tube, a solution containing ytterbium rare earth salt and a co-doperant is injected into the quartz deposition tube. After thorough soaking and drying / shrinking, a rare earth-doped core rod is obtained. During the liner shrinking stage, vapor containing ytterbium compounds is introduced into the tube to reduce the loss of ytterbium oxide due to diffusion and volatilization during the liner shrinking stage, thereby obtaining a uniformly doped ytterbium-doped fiber preform. The preform prepared by this invention has a uniform ytterbium ion concentration distribution in the core layer, and the ytterbium-doped fiber obtained by drawing exhibits high laser slope efficiency.

The present invention provides a semiconductor laser device provided with a stimulated Brillouin scattering layer, relating to the technical field of semiconductor optoelectronic devices. It sequentially includes a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer, and an upper confinement layer from bottom to top. The upper confinement layer and the lower confinement layer are provided with stimulated Brillouin scattering layers; the stimulated Brillouin scattering layer is formed by designing the Mg / C concentration ratio, Mg / O concentration ratio, Mg / H concentration ratio, and Al concentration difference through the structure of the upper confinement layer and the lower confinement layer, so as to limit the propagation of photons and phonons, confine the phonons in the Brillouin zone in the laser, suppress phonon leakage, utilize phonons to manipulate the stimulated Brillouin scattering to reflect the spectrum of a specific wavelength, improve the Brillouin scattering gain coefficient, reduce the absorption loss and internal optical loss of the optical waveguide, improve the laser power and slope efficiency. At the same time, reduce the laser mode number, improve the photon degeneracy, and improve the coherence of the output laser.

The invention belongs to the technical field of laser materials and preparation thereof, and particularly relates to a mid-infrared 2.9 mu m wave band enhanced fluoride laser crystal and a preparation method and application thereof, the chemical composition of the crystal is any one of xHo, yA, zB: Ae1F2 or xHo, yA, zB: Ae1Ae2F4, ho < 3 + > ions are used as active ions, A < 3 + > ions are used as deactivation ions of the Ho < 3 + > ions, and B < 3 + > ions are used as structure regulation ions; 0.5 < = x < = 1.5 at.%, 0.05 < = y < = 0.15 at.%, and 1 < = z < = 30 at.%; the crystal structure belongs to a cubic system, and the space group is Fm-3m (225). Compared with the prior art, the crystal can realize higher luminous intensity in a 2.9 mu m wave band, realizes reversion of fluorescence intensity relative to a 1.9 mu m wave band, has better crystal quality and higher-power intermediate infrared laser output capability, and has the advantages of high gain bandwidth, high gain section, high power, high slope efficiency and the like in an intermediate infrared wave band.

The present application provides an extinction ratio debugging method, apparatus, device and medium based on a multi-channel power meter, relating to the field of optical communication technology. The method includes: when the power of a target channel of the multi-channel power meter reaches a first target power, obtaining a corresponding first bias current; when the power of the target channel reaches a second target power, obtaining a corresponding second bias current; calculating the slope efficiency of a laser in a target optical communication device based on the first target power, the second target power, the first bias current and the second bias current; obtaining a target modulation current based on the slope efficiency, the second target power and the target extinction ratio; setting a Trim value of a register in the target optical communication device by a dichotomy method, and obtaining a current modulation current based on a current ADC value of the register; if the current modulation current is within a preset range of the target modulation current, the debugging is terminated. This method can improve the extinction ratio debugging efficiency of multiple optical communication devices through a multi-channel power meter.

The application discloses a kind of to be related to the field of semiconductor laser, specifically discloses a kind of grating structure for DFB laser and its preparation method, DFB laser.The preparation method of grating structure includes: S1, grating layer is grown on initial epitaxial wafer;S2, grating layer is etched;S3, load into MOCVD reaction chamber, warm up to T1, keep warm first preset time;PH3 is continuously imported during the process of warming up;PH3 is imported flow rate F1 when keeping warm ends;S4, warm up to T2, PH3 and TMIn are continuously imported during the process of warming up;T2-T1>10 ℃, and PH3 import flow rate is increasing during the process of warming up;S5, cool down to T1, PH3 and TMIn are continuously imported during the process of cooling down;PH3 import flow rate is decreasing during the process of cooling down;S6, periodically repeat steps S4 and S5, until buried layer is obtained, grating structure is obtained.The application can reduce grating remelting, improve the crystal quality of grating structure, reduce interface roughness, so as to improve the side mode suppression ratio, slope efficiency of DFB laser.

According to the gallium nitride-based semiconductor laser with the gradually-changed polarized optical phonon energy waveguide layer, a fitting curve of In ion strength distribution or In atom concentration distribution of an upper waveguide layer and a lower waveguide layer is tested through SIMS, and a fitting curve of polarized optical phonon energy distribution meets any function distribution of Log3P1, Lop2P2 and Biphase. The spatial continuous regulation and control of the phonon energy of the optical field are realized, so that the LO phonon energy is continuously and gradually changed along the propagation direction, the phonon energy gradient is formed, the LO phonon scattering is improved, the inelastic scattering and energy relaxation of carriers and LO phonons are inhibited, the carrier transportation and phonon scattering are optimized, the service life of the carriers and the gain retention time are prolonged, and the optical field performance is improved. According to the invention, the threshold current density is reduced, the thermal stability of the laser is improved, the use power and the use temperature of the laser are improved, meanwhile, the phonon energy valley value is matched with the quantum well gain peak, the scattering loss is inhibited, additional scattering caused by phonon energy mutation is avoided, the light field limitation is enhanced, and the slope efficiency is improved.

The application belongs to the technical field of semiconductor lasers, and particularly relates to a VCSEL with a transversely asymmetric active region and a preparation method thereof. The VCSEL comprises, from bottom to top, an N-face electrode, a substrate, an N-type distributed Bragg reflector, a multi-junction cascade active region, an oxidation confinement layer, a P-type distributed Bragg reflector and a P-face electrode. The multi-junction cascade active region is divided into at least two transverse regions in the circumferential direction. The number of active junctions arranged in each transverse region is different. Adjacent active junctions are connected in series through tunnel junctions to form a transversely asymmetric multi-junction cascade active structure. Different numbers of active junctions are arranged in different transverse regions in the same light-emitting aperture, so that each transverse region has differentiated gain capability, threshold current, slope efficiency and output power, thereby forming a transverse power density gradient distribution in the same light-emitting aperture and realizing asymmetric emission characteristics.

The invention provides a gallium nitride-based semiconductor laser with a gradient radiation recombination coefficient waveguide layer, which is characterized in that a lower waveguide layer and an upper waveguide layer are respectively a gradient radiation recombination coefficient lower waveguide layer and a gradient radiation recombination coefficient upper waveguide layer; and a fitting curve of In ion strength distribution or In atom concentration distribution and a fitting curve of radiation recombination coefficient distribution of the waveguide layer on the gradient radiation recombination coefficient both meet any function distribution of GaussAmp, InvsPoly and Hill in an SIMS test. A fitting curve of In ion strength distribution or In atom concentration distribution and a fitting curve of radiation recombination coefficient distribution of the waveguide layer under the gradient radiation recombination coefficient both meet BiDoseResp function distribution in an SIMS test. According to the invention, carriers, quantum recombination and a light field are efficiently localized, the laser gain is improved, the carriers and the light field are efficiently localized in an active layer (quantum well), meanwhile, non-radiative recombination and absorption loss of a waveguide region are inhibited, and the threshold current, slope efficiency and reliability are further improved.

This invention relates to the field of semiconductor device technology, specifically to a semiconductor laser element with a two-dimensional phonon and three-dimensional charge transport layer. The semiconductor laser element has a two-dimensional phonon and three-dimensional charge transport layer between the active layer and the upper waveguide layer, and between the active layer and the lower waveguide layer. This layer is a two-dimensional moiré superlattice structure composed of one or more of SnSe, AgSbT2, SnTe, ZrNiSn, Bi2Te3, and NbFeSb. This layer promotes electronic hybridization, introduces local strain modulation of phonon vibrations, enhances atomic order, reduces phonon scattering, and simultaneously enhances phase transition-induced electron orbital overlap and two-dimensional phonon and three-dimensional charge transport. It also reduces the valence band order of the laser, enhances carrier localization, hole transport, and stimulated emission of the laser element, lowers the excitation threshold of the laser element, enhances bipolar conductivity, improves continuous oscillation below room temperature, enhances the confinement factor and peak gain, reduces the laser voltage, and improves the optical power and slope efficiency of the laser element.

The present invention discloses a gallium nitride-based semiconductor laser element, comprising, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, and an upper confinement layer, with a quantum spin transport layer disposed between the active layer and the lower waveguide layer. The present invention enables the quantum spin transport layer to form a low-dimensional topological structure in which multiple topological surface states coexist, forming Dirac surface states. This structure enables long-distance spin transport under multiple topological protections, and synergistically regulates the topological energy bands and spin transport of the active and waveguide layers, thereby improving the spin-to-charge conversion efficiency, the uniformity of carrier injection into the active layer, the quantum recombination efficiency of the active layer, and the slope efficiency and optical power of the laser.

The semiconductor laser element sequentially comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer from bottom to top, and the quantum oscillation effect layer is arranged between the lower waveguide layer and the lower limiting layer. According to the invention, surface and interface electron scattering is inhibited, a repeated Bloch state is formed to induce quantum oscillation and carrier linear convolution motion, the electron mobility and conductivity are improved, the series resistance and voltage of the laser element after lasing are reduced, and the slope efficiency and luminous efficiency of the laser element are improved; meanwhile, the quantum oscillation effect layer regulates and controls electrode spin Hall injection magneton, improves spin conductivity of the lower waveguide layer and the lower limiting layer, further reduces series resistance and voltage, improves the pinned proportion of quasi Fermi levels of holes and electrons, regulates and controls symmetric breaking away from equilibrium phase change, and improves the performance of the semiconductor device. And the problem of discontinuous or abrupt junction voltage jump of the laser element is solved.

The invention provides an erbium-ytterbium co-doped fiber oblique efficiency test system, a test method and a laser, and belongs to the technical field of laser test. The system comprises a signal light source, a test assembly used for converting input signal light into pumping composite laser transmitted through a to-be-tested optical fiber, a first cladding light stripper and a laser power detector which are sequentially arranged along the output direction of the signal light, the test assembly comprises a first beam combiner connected with a pumping module and a to-be-tested optical fiber, the pumping module comprising at least one first pumping source, and the to-be-tested optical fiber. The specification of the first beam combiner is determined according to the specification of the optical fiber to be tested. According to the specification of the to-be-tested optical fiber, matching of the optical path tail fiber and the to-be-tested optical fiber can be realized on the same test system only by switching the beam combiner to enable the specification of the beam combiner to be consistent with that of the to-be-tested optical fiber, so that full injection of the to-be-tested optical fibers with different specifications is realized; and the oblique efficiency values of the to-be-tested optical fibers with different specifications can be accurately obtained.

According to the gallium nitride-based semiconductor laser with the gradually-changed hole mobility waveguide layer, a fitting curve of In ion strength distribution or In atom concentration distribution, a fitting curve of valence band effective state density distribution and a fitting curve of hole mobility distribution of an upper waveguide layer and a lower waveguide layer which are tested by SIMS all meet any function distribution of ExpGrow1, ExpGrow2, Lorentz and Bradley; energy band degeneracy is improved, ionization impurities, polarization charges and energy band bending restriction are reduced, coupling of a heavy hole band and a light hole band with an SO band is regulated and controlled, valence band effective state density is improved, population inversion and laser gain are enhanced, hole mobility distribution of a waveguide layer is controlled to be in splayed distribution, interface scattering and ionization impurity scattering are inhibited, and the performance of the laser is improved. The hole mobility and the thermal stability are improved, the hole transport efficiency is enhanced, the hole leakage is reduced, and the slope efficiency, the optical power, the aging life and the temperature quenching ratio of the laser are improved.

The invention provides a GaN-based semiconductor laser chip with a kink-inhibiting upper waveguide layer. The GaN-based semiconductor laser chip comprises a substrate, a lower coating layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper coating layer which are sequentially arranged from bottom to top. By designing the refractive index coefficient of the upper waveguide layer, the descending angle of the peak position of hole mobility in the direction of the upper coating layer and the ascending angle of the valley position in the direction of the active layer, the carrier limiting effect of the upper waveguide layer is enhanced, the leakage of electrons to one side of the upper waveguide layer is reduced, the permeation and expansion of carriers to a passive region are inhibited, and the performance of the device is improved. The radiation mode shape distortion is inhibited, the radiation recombination loss is reduced, the radiation recombination efficiency and the external differential component efficiency of a fundamental mode are improved, the threshold current density and the kink critical current are reduced, and the slope efficiency and the optical power of the laser are improved.

The invention discloses an epitaxial structure of a strain compensation type VCSEL (Vertical Cavity Surface Emitting Laser) based on AsH3 flow regulation and control and a preparation method thereof. The epitaxial structure comprises a substrate, and a buffer layer, an N-type DBR (Distributed Bragg Reflector) layer, an active layer, a P-type oxidation limiting layer, a P-type DBR layer and a surface highly-doped GaAs layer are sequentially arranged on the substrate; the N-type DBR layer comprises an N-type high-Al component layer, an Al component transition layer and a low-Al component layer, the P-type DBR layer comprises a P-type high-Al component layer, an Al component transition layer and a low-Al component layer, the active layer comprises a quantum well layer and a quantum barrier layer, the quantum well layer and the quantum barrier layer periodically grow to form the active layer, the quantum well layer is a quantum well layer with compressive strain, and the quantum barrier layer is a quantum well layer with compressive strain. The quantum barrier layer is a tensile strain layer for realizing strain compensation, and the quantum well layer and the quantum barrier layer are alternately arranged to form a periodic structure; the As / P proportion can be accurately controlled to achieve dynamic strain compensation, the As component of the barrier layer is progressively increased to form gradient tensile strain, well layer compression strain is offset, atom mutual diffusion is restrained, P atoms are restrained from diffusing to the well layer, threshold current is reduced, slope efficiency is improved, and characteristic temperature is improved.

The invention discloses a group III nitride semiconductor laser element which sequentially comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer from bottom to top. The Fermi noodle topological layer comprises a first Fermi noodle topological layer, a second Fermi noodle topological layer and a third Fermi noodle topological layer. According to the invention, through specific design of conduction band effective state density distribution and thermal conductivity distribution, vertically downward energy band movement is formed to change a Fermi surface topological structure, disorder and instability of electron spinning are reduced, state density in a valence band is reduced, and transition probability is increased to reduce threshold current density, hole migration barrier and electron leakage; the electron hole confinement effect of the active layer is improved, and the stimulated radiation recombination efficiency is enhanced, so that the optical power and the slope efficiency are improved.

The invention discloses a GaN-based semiconductor laser element which comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer, spin-orbit coupling layers are arranged in the lower limiting layer and the lower waveguide layer, and the spin-orbit coupling layers are designed to be used for regulating and controlling phase-locked laser response and near-field beam guidance. Mode competition is suppressed, the laser suppression ratio is improved, light field dissipation is reduced, coherence and mode gain of laser are improved, the line width of the laser is reduced, and a light beam quality factor is improved; by designing conduction band effective state density distribution, electron affinity distribution and electron effective mass distribution of the spin-orbit coupling layer, a quantum Hall system with relatively strong net spin density and super-strong second-order nonlinear Hall effect is formed, nonlinear optical polarizability is enhanced, population distribution inversion of the active layer is accelerated, and the quantum Hall effect is improved. The active layer state density is enhanced to improve spontaneous radiation and stimulated radiation, and the lasing power and slope efficiency of the laser element are improved.

The application provides a semiconductor laser element with a Fermi surface topological layer, which comprises, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper confinement layer; a Fermi surface topological layer is arranged between the upper confinement layer and the electron blocking layer and / or between the lower confinement layer and the lower waveguide layer; and the Fermi surface topological layer is a two-dimensional topological Moire superlattice structure. The Fermi surface topological layer is arranged between the upper confinement layer and the electron blocking layer and / or between the lower confinement layer and the lower waveguide layer; the Fermi surface topological layer can change the Fermi surface topological structure by moving the energy band vertically downward, reduces the disorder and instability of electron spin, improves the injection efficiency of electrons and holes, and the radiation recombination efficiency of the active layer of the laser element; meanwhile, the bipolar conductance is enhanced to improve the confinement factor and solve the saturation problem of the carrier concentration of the active layer, so that the excitation threshold of the laser element is reduced, and the optical power and the slope efficiency of the laser element are improved.

The invention discloses a semiconductor laser with a lower waveguide layer for suppressing heat fading, which sequentially comprises a substrate, a lower coating layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper coating layer from bottom to top, the waveguide layer under the low oscillation threshold is any one or any combination of an InGaN / GaN superlattice, an InGaN / AlGaN superlattice, an InGaN / AlInGaN superlattice, an InGaN / AlInN superlattice, a GaN / AlGaN superlattice, a GaN / AlInGaN superlattice and a GaN / AlN superlattice, and the thickness of the waveguide layer under the low oscillation threshold is 5-1000 nm. The waveguide side wall scattering loss and quantum well absorption loss of the laser are reduced, the internal light absorption loss of the laser is reduced, heat fading caused by non-radiative recombination is inhibited, the threshold current of the laser is reduced, and the slope efficiency is improved.

The semiconductor laser element sequentially comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer from bottom to top, and the quantum limiting stark regulation and control layer is arranged between the active layer and the lower waveguide layer. The electric field distribution of the active layer is regulated and controlled, domain wall motion is induced to be generated, the quantum limited stark effect and InN phase separation of the active layer are inhibited, the interface quality is improved, and the non-radiative recombination center is reduced; light field limitation and limiting factors are enhanced, and the light power of the laser is improved; the quantum confinement stark regulation and control layer generates lattice displacement to induce phase change, improves mutual solution gaps of InN and GaN, inhibits InN segregation of the active layer and the waveguide layer, reduces In component fluctuation, reduces thermal degradation, improves interface crystal quality and thermal stability, reduces a non-radiative recombination center, and improves laser power and slope efficiency.