60 results about "Slope efficiency" patented technology

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.

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 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 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.

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 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 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 application discloses an anti-photon darkening active optical fiber preform, an optical fiber and a preparation method thereof. First, a quartz lining pipe with a loose core layer deposited on the inner surface is prepared by using an MCVD process, a tail pipe at one end is heated and broken, a mixed solution containing ytterbium-containing rare earth salt and aluminum and cerium-containing co-doping agent is injected into the deposited pipe, and after being soaked sufficiently, drying and melting, a rare earth doped core rod can be obtained, and the anti-photon darkening active ytterbium doped optical fiber can be obtained by directly drawing the core rod or drawing the core rod with an outer sleeve pipe. The ytterbium doped optical fiber prepared by the application has an equilibrium state photon darkening additional loss lower than 10 dB / m at 633 nm, and compared with the existing ytterbium doped active optical fiber, the anti-photon darkening performance is greatly improved without affecting the key performances such as fiber absorption and slope efficiency.

The application provides a semiconductor laser element provided with a conductive phase change layer, and relates to the technical field of semiconductor photoelectric devices, and 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 conductive phase change layer is arranged between the lower waveguide layer and the lower limiting layer and between the upper waveguide layer and the electron blocking layer; the conductive phase change layer has a reversible control phase change field; the phase change during the high-low temperature change in the epitaxial growth process is controlled; the phase change rate is improved from the minute order of magnitude to the picosecond order of magnitude; the resistivity and the carrier potential barrier are reduced; the single transverse mode lasing current and the threshold voltage are reduced; meanwhile, the conductive phase change layer also has a reversible control strain field; the uneven thermal stress distribution is improved; the In component fluctuation and segregation of the active layer are inhibited; the interface quality of the active layer is improved; the thermal stability and the optical catastrophe damage are inhibited; the confinement factor of the laser element is enhanced; and the lasing power and the slope efficiency of the laser element are improved.

The application relates to a Tm / Ho:YAG-SiO2 special optical fiber, a 2-micron single-frequency fiber laser based on the optical fiber and a preparation method, and belongs to the fiber laser field. The core of the special optical fiber is Tm / Ho:YAG, and the outer cladding is SiO2. The laser comprises a pump source, a fiber wavelength division multiplexer A and a laser resonant cavity arranged along an optical path. The pump source adopts a semiconductor LD. The laser resonant cavity is composed of a pair of fiber Bragg gratings, including a low-reflectivity Bragg grating and a high-reflectivity Bragg grating. The special optical fiber is arranged between the low-reflectivity Bragg grating and the high-reflectivity Bragg grating. The special optical fiber is prepared by a melting core method. The doping of Ho improves the absorption capacity of the gain optical fiber to the pump and the gain at the 2-micron waveband. The Tm / Ho:YAG-SiO2 special optical fiber is used to output a 2-micron waveband single-frequency fiber laser with higher output power and higher slope efficiency. 3+ ​

The application discloses a semiconductor green laser element, which comprises, from bottom to top, a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer in sequence, wherein the upper waveguide layer and the upper limiting layer are provided with a topological phonon transition layer, and the topological phonon transition layer comprises a first topological phonon transition layer, a second topological phonon transition layer and a third topological phonon transition layer. The application realizes the synergistic regulation of phonon transport, reduces the phonon scattering of the laser element, enhances the lattice thermal conductivity, improves the thermoelectric performance of the laser element, improves the heat dissipation performance of the laser element, reduces the heat accumulation of the active layer, reduces the temperature of the active layer, reduces the hole injection barrier and improves the hole injection efficiency, improves the overlap probability of the electron-hole wave function of the active layer, thereby strengthening the laser element, improving the aging light attenuation, the aging life and the reliability under the condition of high power and large current, and improving the lasing power and the slope efficiency of the laser element.

The invention discloses an aging compensation method for an optical device, and belongs to the technical field of optical device power compensation. The method comprises the following steps: constructing a statistical prediction model, and calculating a theoretical compensation amount of a driving current of a to-be-compensated optical device at a t moment by using the statistical prediction model; constructing a real-time feedback model, and calculating the feedback compensation amount of the driving current of the to-be-compensated optical device at the t moment by using the real-time feedback model; establishing a weighting function based on the life time inflection point of the optical device; the theoretical compensation amount and the feedback compensation amount are subjected to weighted fusion through a weighting function, and the final fusion compensation amount of the driving current of the to-be-compensated optical device at the t moment is obtained; and when the ratio of the slope efficiency at the t moment to the initial slope efficiency is less than 0.95 and the final fusion compensation amount is within the compensation boundary condition, compensating the driving current of the to-be-compensated optical device at the t moment based on the final fusion compensation amount. While the economic benefit of the optical device is improved, a better use effect of the optical device can be ensured.

The application provides a semiconductor laser element provided with an ion conjugate layer, and relates to the technical field of semiconductor photoelectric devices, and sequentially comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper limiting layer from bottom to top; the ion conjugate layer is arranged between the active layer and the upper wave layer and between the active layer and the lower waveguide layer; the ion conjugate layer can improve the molar absorption coefficient and compensate the polarization field, induce local polarization, and then regulate the carrier and Fermi level, improve the small rabbit degeneracy of the laser element, reduce the absorption loss of the free carrier, promote the stimulated radiation to exceed the spontaneous radiation, improve the particle inversion of the non-equilibrium carrier in the resonant cavity of the laser element, reduce the lasing threshold, realize the room-temperature continuous oscillation, improve the slope efficiency of the laser element, reduce the valence band step of the active layer, improve the hole injection efficiency and injection uniformity, and improve the peak gain and gain uniformity of the laser element.

The present invention discloses a semiconductor laser element with strained polarity topological layers. The element comprises, 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. A strained polarity topological layer is disposed between the upper waveguide layer and the upper confinement layer. The strained polarity topological layer comprises a first strained polarity topological layer, a second strained polarity topological layer, and a third strained polarity topological layer. The present invention utilizes a specific spontaneous polarization coefficient distribution and a specific Philips ionization degree distribution to generate polarity anti-vortices and polarity topological properties, shielding mechanical losses, reducing the strain polarization effect of the active layer, lowering the hole injection barrier, improving carrier injection uniformity, and increasing the overlap probability of electron-hole wave functions in the active layer. This improves the mode gain of the laser, enhances the confinement factor and gain uniformity, reduces the excitation threshold of the laser element, and improves the optical power and slope efficiency of the laser element.

The application discloses a semiconductor laser element in the violet-ultraviolet wave band, which comprises, 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, wherein the upper waveguide layer and the upper confinement layer are provided with an interlayer coherent hole tunneling layer, and the interlayer coherent hole tunneling layer comprises a first interlayer coherent hole tunneling layer, a second interlayer coherent hole tunneling layer and a third interlayer coherent hole tunneling layer. The application constructs a highly periodic electrostatic potential, tunes Feshbach molecular resonance to enhance the interaction between excitons and holes residing in different layers in the laser, reduces the Mg acceptor activation energy of the p-type semiconductor, improves the ionization efficiency of Mg, thereby inducing the interlayer coherent hole tunneling injection of the hole generation layer of the laser into the active layer, improving the hole injection efficiency of the active layer, improving the matching degree and uniformity of the electrons and holes in the active layer, and improving the optical power and slope efficiency of the laser element.

The application provides a semiconductor laser element provided with a triplet exciton enrichment layer, and relates to the technical field of semiconductor photoelectric devices, and sequentially comprises 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 triplet exciton enrichment layer is arranged between the active layer and the upper wave layer and between the active layer and the lower waveguide layer; compared with the prior art, the triplet exciton enrichment layer is arranged between the active layer and the lower wave layer and between the lower confinement layer and the lower waveguide layer; in the laser element, the triplet exciton is enriched in the active layer through energy transfer, and is converted into a radiative monopole exciton through spin coupling inversion, so that the electron-hole wave function in the active layer realizes a radiative recombination efficiency close to 100%, the confinement factor is enhanced, continuous oscillation is realized, the excitation threshold of the laser element is reduced, and the optical power and the slope efficiency of the laser element are improved.

The application provides a semiconductor laser element with a built-in topological flat band layer, and relates to the technical field of semiconductor optoelectronic devices, 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, an upper confinement layer, and a topological flat band layer arranged between the upper waveguide layer and the electron blocking layer; the topological flat band layer is any one or any combination of KMn6Bi5, KAg(CN)2, Pb2SbO7, Rb2CaH4 and Ca2NCl; the topological flat band layer has unique magnetic and superconducting properties, has flat band orbital characteristics and quasi-planar energy band hybridization, forms a stable closed ring Dirac nodal line which is not easy to be destroyed, reduces energy dispersion, induces reduced refractive index dispersion, improves the confinement factor, enhances mode gain, and at the same time, generates in-plane anisotropy and vibrational anisotropy, reduces optical waveguide absorption loss, and reduces internal optical loss, so as to strengthen the stimulated emission of the laser element, and improve the lasing power and slope efficiency of the laser element.

The present invention discloses a laser gain device and its preparation method. The device comprises, from bottom to top, a substrate, a bonding layer, a laser gain crystal, and a cladding. The bonding layer is formed by bonding a first bonding intercalation layer to a second bonding intercalation layer, the second bonding intercalation layer being located above the first bonding intercalation layer. The preparation method mainly involves heterogeneous bonding of the laser gain crystal to the substrate, etching the laser gain crystal, and preparing the cladding. The laser gain device of the present invention enables laser light to propagate within a micron-scale laser crystal waveguide. The higher optical density reduces the laser oscillation threshold and improves the slope efficiency of the laser output. Furthermore, the present invention has the advantages of small size, high stability, and ease of integration, providing a new possibility for integrated on-chip light sources.

The utility model discloses a double-end pumping large-energy 755nm laser, which comprises a first pumping source, a second pumping source, a resonant cavity, a first shaping module and a second shaping module, the resonant cavity is internally provided with emerald arranged between the first pumping source and the second pumping source, and the double-end pumping large-energy 755nm laser further comprises a first shaping module and a second shaping module which are respectively butted with light output ends of the first pumping source and the second pumping source. The resonant cavity further comprises a total reflection mirror, an output mirror, a first coupling mirror and a second coupling mirror, the first coupling mirror is arranged between the first shaping module and the jade, the first coupling mirror and the total reflection mirror are oppositely arranged, the second coupling mirror is arranged between the second shaping module and the jade, and the second coupling mirror and the output mirror are oppositely arranged. According to the scheme that the pumping sources are arranged at the two ends, pumping laser energy is increased, the characteristics that the emerald laser is high in threshold value and oblique efficiency are combined, and therefore 755nm hundred picosecond laser output is greatly improved, and the practical effect is obvious.