258 results about "Lattice constant" patented technology

A light-emitting device includes a light-emitting part. The light-emitting part contains a quantum dot. The quantum dot has a core and a shell. The shell is located outside the core. Each of the core and the shell has a hexagonal structure. The lattice constant of the core is larger than the lattice constant of the shell.

The invention relates to the technical field of topological photonic crystals, in particular to a topological energy valley photonic crystal, a broadband topological slow light waveguide and a topological beam splitter. The crystal comprises a substrate and a nanorod array arranged on the substrate, the nanopillar array is formed by arranging a plurality of unit cells with honeycomb structures, and the two-dimensional cross section of each unit cell is a regular hexagon; each unit cell is formed by arranging two kinds of nano columns with different section diameters at intervals; two adjacent unit cells share one edge; the two nano columns with different section diameters are respectively a first nano column and a second nano column, and the diameter of the first nano column is twice that of the second nano column; and the value range of the lattice constant a is 480-520 nm. The method has the advantages that the problem of broadband slow light regulation and control in the topological optical waveguide is solved; brillouin region winding of an energy valley boundary state mode is realized, and the group velocity of a light mode is reduced; the light transmission robustness is improved; the back scattering loss caused by manufacturing defects and disorder is reduced; and the applicable frequency range of the device is widened.

The invention discloses an ion doping method based on first principle calculation and application thereof. Relates to the technical field of building materials. The method comprises the following steps: firstly, constructing a cement clinker mineral phase crystal structure model, and performing structural relaxation on the model to obtain a model crystal structure with a determined lattice constant; secondly, analyzing and optimizing microstructure changes and corresponding energy state changes of various mineral phases in the ion doping process by utilizing a quantum mechanical simulation means, representing the solid solubility of doped ions and mineral phase structures through the defect formation energy of ion doping, forming energy being negative reaction process being spontaneous process, the closer to 0, the better the solid solubility, and the more to 0, the better the solid solubility; therefore, how to enhance the hydration reaction activity and improve the strength by ion doping is disclosed. The mechanical property, durability and corrosion resistance of the cement are improved by accurately regulating and controlling the characteristics of the multi-mineral-phase structure.

The invention discloses a nanocrystal magnetic material and a preparation method thereof, the nanocrystal magnetic material is a magnetic Nb3VSe6 crystal and comprises three elements, namely Nb, V and Se, the metered molar ratio of the three elements is 3: 1: 6, the crystal has a centrosymmetric broken hexagonal layered structure, the space group of the crystal is P6322, V atoms are inserted between two 2H-NbS2 hexagonal layers, the lattice constants a = b = 5.738, and c = 12.018. The magnetism in the material is mainly contributed by positive trivalent Cr ions, the magnetic moment is 3B, the local electron spin S is equal to 3 / 2, and conduction electrons are from unfilled bands of Nb atoms. Due to the unique crystal structure and electronic property, the material shows potential application value in multiple fields, especially in the aspects of high-frequency devices, spintronics elements, magnetic dampers and the like. The Nb3VSe6 single crystal is relatively stable in air, which is a great advantage for practical application.

The invention relates to a metal oxide and application thereof. The metal oxide is of a face-centered cubic structure, the space group is Fd-3m, the lattice constant a of the metal oxide is # imgabs 0 # to # imgabs 1 #, and the tensile residual stress F1 in the metal oxide is 0.105 MPa to 5.51 MPa, or the compressive residual stress F2 in the metal oxide is 1.05 MPa to 8.6 MPa; the metal oxide is prepared by a spray pyrolysis method, and the pyrolysis rate K is 0.361 to 48.611. The metal oxide provided by the invention not only has relatively high crystallinity and stability, but also has high activity, and is beneficial to improving the intercalation of sodium ions or lithium ions when the positive electrode material is prepared, so that the comprehensive electrical property is improved.

The invention provides a Si-based InGaAs photoelectric detector and a preparation method thereof. The Si-based InGaAs photoelectric detector comprises a Ge transition layer, a GaAs transition layer and a non-doped InP buffer layer, wherein the Ge transition layer, the GaAs transition layer and the non-doped InP buffer layer sequentially grow on the surface of a silicon substrate; the lower doped InP layer, the non-doped InGaAs absorption layer and the upper doped InP layer are sequentially grown on the surface of the non-doped InP buffer layer. The Si-based Ge epitaxial layer, the Ge-based GaAs epitaxial layer and the GaAs-based InP epitaxial layer which are mature in process are sequentially inserted between the Si substrate and the III-V group heteroepitaxial thin film, the crystal structure type difference of direct epitaxial growth of InGaAs on Si is eliminated, the lattice constant mismatch degree is reduced, the defects of the InGaAs epitaxial layer are reduced, the quality is improved, and a high-performance detector is better prepared.

The invention discloses an alloy high-temperature and high-pressure environment simulation method under radiation action based on molecular dynamics, which comprises the following steps: establishing a molecular structure framework of an alloy according to a crystal structure and a lattice constant of the alloy, and setting initial parameters to construct an initial simulation model; performing relaxation operation on the molecular structure model in a high-temperature and high-pressure environment; performing irradiation damage simulation on the relaxed model based on molecular dynamics, selecting a central atom as a primary off-site atom, and setting incident energy and incident direction of the primary off-site atom to simulate atom cascade collision; keeping the incident direction unchanged, and adjusting the incident energy of the primary off-site atoms to obtain defect distribution and defect density under different energies; and analyzing the defect evolution law of the alloy in the high-temperature and high-pressure environment according to the simulation result. According to the method, the alloy material is observed from a microscopic atomic scale, so that a powerful support is provided for simulating a defect evolution process in a high-temperature and high-pressure environment and reflecting atomic collision of the alloy in a real radiation environment.

This application relates to a monolithically integrated multi-wavelength topological cavity surface-emitting laser (PCSEL) array. According to one embodiment, a monolithically integrated PCSEL array includes multiple PCSELs formed from the same semiconductor layer, at least one layer of which is formed as a photonic crystal layer, or the laser also includes a separate photonic crystal layer. The photonic crystal layer includes multiple supercell structures, each with substructures having multiple independent one-dimensional parameters. At least two independent one-dimensional parameters of one or more substructures are modulated to be greater than or less than their equilibrium position to open the Dirac point of the supercell's bandgap at the equilibrium position. Around any point in the photonic crystal layer, the modulation of the two independent one-dimensional parameters of the supercell forms a vortex structure, which corresponds in parameter space to one or more turns around the equilibrium position. The supercell lattice constants of the two lasers can be different to emit lasers of different wavelengths.

The invention relates to the technical field of additive manufacturing, in particular to an additive manufacturing low-stress high-entropy alloy design system and method based on lattice mismatch, which are used for effectively reducing interface stress of gradient materials, and the method comprises the following steps: analyzing a matrix crystal structure, and determining a high-entropy alloy crystal structure type consistent with the matrix crystal structure; based on a high-entropy alloy crystal structure, a high-entropy alloy virtual lattice approximate structure model is established; performing structure geometric optimization on the model to obtain a high-entropy alloy lattice constant under a stable structure; according to the obtained lattice constants, the proportion of all elements of the high-entropy alloy is adjusted by comparing the lattice constants of the base body, and the redesigned high-entropy alloy is calculated till the lattice mismatch degree of the high-entropy alloy and the base body is low; and gradient design is conducted on the designed high-entropy alloy with the low lattice mismatch degree and the base body, and the design result of the low lattice mismatch degree and the low interface stress of the additive manufacturing high-entropy alloy gradient material is obtained.

According to the optical metasurface filter and method for tunable edge directional enhancement, the angle of the metasurface can be rotated in a simple mechanical tuning mode, tuning of the edge enhancement direction of an amplitude or phase sample is achieved, edge filtering in different directions is achieved in an efficient and compact mode, and the optical metasurface filter and method have the advantage of chip-level ultrafast optical calculation. The invention discloses a polarization-sensitive vertical edge detection filter which is constructed by a metasurface and an optical 4F system. The metasurface (10) comprises an amorphous silicon cuboid nano brick unit (1) and a silicon dioxide substrate (2), each amorphous silicon cuboid nano brick unit has a fixed square lattice constant Px = Py = 300nm, a height H = 365nm and designed L = 129nm and W = 90nm, and the amorphous silicon cuboid nano brick units are periodically arranged on the silicon dioxide substrate; the phase is changed by changing the orientation angle theta of the amorphous silicon cuboid nano brick unit, and required phase distribution is completed.

The invention discloses a low-temperature AB2 type hydrogen storage alloy as well as a preparation method and application thereof, and relates to the technical field of hydrogen storage alloys. According to the low-temperature AB2 type hydrogen storage alloy, the YAl alloy with specific components and proportions is doped into the AB2 type hydrogen storage alloy, the low-temperature hydrogen desorption performance of a matrix is improved, the crystal structure of the obtained hydrogen storage alloy is a C14Laves phase, the lattice constant a is 0.48-0.49 nm, activation can be achieved at the low temperature of-40 DEG C or below, the hydrogen desorption plateau pressure of-40 DEG C is 0.1-1.0 MPa, and the hydrogen desorption performance of the low-temperature AB2 type hydrogen storage alloy is improved. The hydrogen storage capacity is guaranteed, and meanwhile the hydrogen desorption capacity can be improved to the maximum extent, so that the hydrogen storage capacity of the alloy at the temperature of minus 40 DEG C reaches 1.9 wt% or above, and the hydrogen desorption capacity also reaches 1.75 wt% or above.

The invention relates to a method for constructing a deep learning potential function of a lithium alloy, which comprises the following steps of: establishing initial crystal models of magnesium-lithium alloys with different lithium contents, and carrying out structure optimization on the models to obtain equilibrium state lattice constants; and respectively constructing an elastic constant calculation model, a surface energy calculation model, an interstitial atom defect model and a vacancy defect model. The method comprises the following steps: applying a strain component, calculating a strain energy fitting elastic constant component, calculating surface energy after cutting a supercell structure and optimizing, calculating formation energy after determining a gap position, and introducing a vacancy to form the supercell structure and calculating the formation energy. And inputting the data set into a deep learning framework, optimizing model precision by adjusting truncation radius parameters, and finally generating a magnesium-lithium alloy deep learning potential function. Compared with the prior art, the method has the advantages that the problem that a classic MEAM potential function cannot accurately predict the variation trend of the basal plane fault energy along with the lithium content is solved, the defect of low calculation efficiency of a first principle is overcome, and the calculation efficiency close to that of an empirical potential function is realized.

The invention relates to a high-entropy alloy local lattice distortion quantitative calculation method and system and a medium, the high-entropy alloy local lattice distortion quantitative calculation method comprises the following steps: S1; collecting an X-ray diffraction spectrogram of the high-entropy alloy; s2, analyzing and determining the crystal structure of the high-entropy alloy according to the X-ray diffraction spectrogram; s3, calculating to obtain a lattice constant according to the lattice structure through full-spectrum fitting of the X-ray diffraction spectrogram; s4, according to the geometrical relationship between the lattice constant and the crystal structure, calculating to obtain an average atom pair spacing; s5, fine structure spectrums absorbed by X rays of different alloy elements K-edge or L-edge in the high-entropy alloy are collected; s6, analyzing and determining the average atom pair spacing of the specific element and the nearest neighbor element; and S7, the local lattice distortion amount and the average lattice distortion amount of specific element atoms of the high-entropy alloy are obtained through calculation. According to the method, the quantitative calculation of the local lattice distortion of the high-entropy alloy with the element recognition capability is realized.

A magnetoresistive random-access memory cell includes a first magnetic layer having a first lattice constant; a second magnetic layer having a second lattice constant; and a tunnel barrier between the first and second magnetic layers. The tunnel barrier includes at least one oxide layer with an oxide layer lattice constant. The oxide layer lattice constant has a mismatch smaller than six percent with at least one of the first and second lattice constants.

This powder satisfies requirements 1 and 2. Requirement 1: |dA(T) / dT| satisfies 10 ppm / ° C. or more at at least one temperature T1 in a range of −200° C. to 1200° C. A is (a-axis (shorter axis) lattice constant) of a crystal in the powder) / (c-axis (longer axis) lattice constant of the crystal in the powder), and each of the lattice constants is obtained by X-ray diffractometry of the powder. Requirement 2: a particle diameter D50 at a cumulative frequency of 50%, a particle diameter D10 at a cumulative frequency of 10%, and a particle diameter D90 at a cumulative frequency of 90% in a volume-based cumulative particle diameter distribution curve obtained by a laser diffraction scattering method satisfy conditions (I) and (II): (I) D10 / D50 is 0.05 or more and 0.45 or less; and (II) D90 is 0.5 μm or more and 70 μm or less.

The invention provides a method for in-situ measurement of an internal stress state of an ultrathin film surface by using RHEED, and relates to the technical field of condensed state substance structure detection, and the method comprises the following steps: epitaxially growing an ultrathin film on a substrate by using film growth equipment; irradiating the ultrathin film by using an RHEED electron beam to obtain a diffraction pattern, and obtaining characteristic parameters of the diffraction pattern; obtaining the lattice constant of the ultrathin film through the characteristic parameters of the diffraction pattern; based on the lattice constant of the ultrathin film, the stress type and strain borne by the ultrathin film are determined. According to the method, the distance between diffraction fringes in a diffraction pattern is accurately extracted from a simple RHEED image, the lattice constant from the diffraction pattern is calculated, the stress state of the ultrathin film is accurately judged by comparing lattice constants in a stress-free state, existing equipment does not need to be greatly modified, and the method is simple and convenient to operate. The method can be realized only by using the existing RHEED electron beam and image processing software.

Systems and methods are disclosed for making a quantum network node. A plurality of scoring function F values are calculated for an array of at least two photonic crystal cavity unit cells, each having a lattice constant α and a hole having a length Hx and a width Hy. A value of α, a value of Hx, and a value of Hy are selected for which a scoring function value is at a maximum. A waveguide region and the array of at least two photonic crystal cavity unit cells based on the selected values are formed on a substrate. At least one ion between a first photonic crystal cavity unit cell and a second photonic crystal cavity unit cell are implanted and annealed into a quantum defect. A coplanar microwave waveguide is formed on the substrate in proximity to the array of at least two photonic crystal cavity unit cells.

In an embodiment a method for processing an optoelectronic component includes providing a growth substrate having a first lattice constant, epitaxially depositing a sacrificial layer based on GaN with a dopant concentration higher than 1e18 atoms / cm3 having a second lattice constant different from the first lattice constant, epitaxially depositing a top layer having a lower doping concentration than the sacrificial layer based on GaN having a third lattice constant different from the first lattice constant, wherein a growth of the sacrificial layer and the top layer generates a plurality of dislocations on a surface of the top layer, and electrochemically porosifying the sacrificial layer through the dislocations on the exposed first portions such that the sacrificial layer below the second portions is at least partially porosified and forming a functional layer stack onto the second portions based on an InGaN semiconductor material.

The invention discloses a method for determining the alloy gene sequence and performance of a metal material, which comprises the following steps of: constructing a basic atomic group sequence, a characteristic atom sequence and a characteristic crystal sequence of an alloy system, determining basic information of the alloy gene sequence, and calculating the change of alloy gene concentration along with component components. Calculating physical property information such as electronic structures, binding energy and lattice constants of alloy genes in the alloy system; according to the determined physical property information of the alloy gene sequence, a holographic information database of the alloy gene is constructed, and the structure and performance of the alloy are clarified. According to a small amount of experimental data, on the basis of a systematic alloy scientific theory, the physical property of an alloy gene is calculated on the basis of a numerical calculation method according to the concentration of the alloy gene and information of a gene sequence, so that the structure and the property of the alloy are predicted.

Provided is a surface-emitting laser capable of obtaining desired characteristics while suppressing the occurrence of structural defects. A surface emitting laser according to the present technology includes a resonator including: a first structure including a substrate and a first reflector stacked on each other; a second structure including a second reflector and disposed on a side of the first reflector of the first structure; and an intermediate structure including an active layer and disposed between the first and second structures. The substrate is made of a material having a lattice constant greater than that of GaAs and less than that of AlAs. The first reflector and the intermediate structure are made of different material systems. According to the present technology, it is possible to provide a surface-emitting laser capable of obtaining desired characteristics while suppressing the occurrence of structural defects.

The invention relates to a method for reducing anisotropy of an intermetallic compound Cu6Sn5, and belongs to the technical field of lead-free welding. The method comprises the following steps: doping alloy elements such as Ag, Ni / Co or Ni / Co / Ag into Cu6Sn5, forming a ternary phase intermetallic compound under a high-temperature condition, and stabilizing a Cu6Sn5 crystal structure. The doped elements enhance the structural stability through displacement solid solution and orbital hybridization, inhibit lattice anisotropy and hardness difference, and improve the mechanical properties of the material. The prepared alloy shows that the anisotropy is obviously reduced in the aspects of Vickers hardness, lattice constant, elasticity modulus and the like through verification of a first principle and testing of multiple groups of samples. According to the method, the reliability and the service life of the welding spot structure can be improved and prolonged without a complex processing flow, and the method is suitable for interface stability enhancement and service performance optimization of the lead-free solder welding spot.

The application provides a yttrium barium copper oxide photonic crystal and a preparation method thereof. 7‑x The photonic crystal structure is composed of periodic yttrium barium copper oxide (YBa2Cu3O 7‑x ) superconducting material circular crystal columns, the lattice constant is 2630nm, and the radius of the circular crystal column is 500nm. The photonic crystal can change the position and width of the band gap by changing the light incidence angle, so that the middle infrared band gap is realized. The photonic crystal is prepared by adopting a magnetron sputtering method to prepare a yttrium barium copper oxide film on a strontium titanate single crystal substrate, and then adopting a focused ion beam method to process the yttrium barium copper oxide film into a periodic nanostructure composed of yttrium barium copper oxide circular crystal columns, so that the yttrium barium copper oxide photonic crystal is obtained. The preparation method of the yttrium barium copper oxide photonic crystal is simple and easy to control.

The invention provides a multi-mode laser optical frequency comb device and a degeneracy degeneration multi-mode control method. The device comprises a diamond crystal, an optical frequency sparse generation module and a degeneracy control module. According to the embodiment of the invention, based on the multi-mode laser optical frequency comb device, stress is applied to the diamond crystal and the lattice constant of the diamond crystal is regulated and controlled according to a degenerate and degenerate multi-mode control method, so that the degeneracy of Raman vibration is regulated and controlled, the optical frequency sparse mode is controlled, and the existing single-mode laser optical comb is regulated into the multi-mode laser optical comb for output; the multi-mode optical frequency comb formed by the single-mode optical frequency comb capable of generating a single mode or a plurality of spectral width intervals has the advantages of being wide in wavelength coverage range, large in spectral interval, capable of generating a plurality of spectral width intervals and tunable in spectral width interval.

The invention relates to the technical field of semiconductor materials, and discloses an III-V wafer, a preparation method of the III-V wafer, an on-chip light source and a preparation method of the on-chip light source. The III-V wafer comprises a substrate (1), an epitaxial layer (2) and a strain superlattice layer (3), wherein the epitaxial layer (2) and the strain superlattice layer (3) are sequentially arranged on the substrate (1). Wherein the strained superlattice layer (3) comprises a strained superlattice layer I (31) and a strained superlattice layer II (32), the strained superlattice layer II (32) is in contact with the epitaxial layer (2), and the lattice constant of the material of the strained superlattice layer I (31) is smaller than that of the material of the strained superlattice layer II (32). According to the III-V wafer provided by the invention, the strain superlattice layers with different lattice constants are arranged on the epitaxial layer, so that interface defects can be eliminated, the luminous efficiency of an on-chip light source is improved, the service time of the on-chip light source is prolonged, and the reliability is enhanced.

The application relates to the technical field of semiconductor material preparation, in particular to a liquid phase epitaxial growth method and equipment for dynamically regulating lattice mismatch. The specific content is as follows: a substrate is pretreated to prepare micro pits and grooves of the substrate, and a uniform solution is prepared according to phase diagram information; a temperature gradient is set in a multi-zone temperature control epitaxial furnace, and the epitaxial growth of the substrate is controlled through a boat device; the substrate and the solution pool are sequentially moved into the furnace; during the epitaxial growth process, the lattice constant error, morphology and photoelectric properties of the growth are detected, and when the detection signal deviates from the predetermined threshold, the lattice mismatch is compensated by adjusting the solution concentration and the temperature; during the displacement process, the mother liquor remaining between different layers is poured into the grooves of the substrate through the inclined substrate. The application solves the problem of lattice mismatch control by real-time detection and real-time regulation of the lattice mismatch, and improves the quality and performance of the epitaxial layer.

The invention provides a positive electrode material, a positive plate and a lithium ion battery, the positive electrode material is a ternary layered oxide and comprises single crystal particles and polycrystal particles, the mass ratio of the polycrystal particles to the single crystal particles satisfies 9: 1-6: 4, the positive electrode material has a chemical general formula LiNixCoyMzO2, M is Mn or Al, x is more than or equal to 0.80 and less than or equal to 0.95, y is more than 0 and less than 0.25, and z is more than 0 and less than 0.2; the polycrystalline particles are secondary particles formed by sintering and agglomerating primary crystal grains at a high temperature, and the particle size of the primary crystal grains meets the following conditions: the shortest Freight diameter A is more than or equal to 0.1 mu m and less than or equal to 0.6 mu m; the longest Feret diameter B is greater than or equal to 0.2 mu m and less than or equal to 1.0 mu m; an aspect ratio B / A: 1.0 < = B / A < = 3.5; the morphology of the polycrystalline particles meets the relational expression that (B / A) * e ((k * c / a)) is larger than or equal to 30 and smaller than or equal to 100, and c / a is the lattice constant ratio of the polycrystalline particles; and k is the ratio of I003 to I104. According to the control standard for monitoring the two-dimensional microtopography of the primary crystal grains and the secondary particles of the polycrystalline particles by using a relational expression that (B / A). E ((k. C / a)) is greater than or equal to 30 and less than or equal to 100, the electrochemical performance of the positive electrode material can be evaluated more accurately, and the performance standardization control effect of a terminal battery product is improved.

The hydrogen separation filter includes a porous substrate and a super lattice layer on the porous substrate. The super lattice layer includes at least one lattice expansion layer containing a first material and at least two hydrogen dissociation and permeation layers containing a second material selected from the group consisting of Pd, V, Ta, Ti, Nb, and alloys thereof. The at least one lattice expansion layer and the at least two hydrogen dissociation and permeation layers are alternately stacked. The first material and the second material have a same crystalline structure. A lattice constant a1,bulk of a first bulk material haying a same composition and a same crystalline structure as the first material and a lattice constant a2,bulk of a second bulk material having a same composition and a same crystalline structure as the second material satisfy Formula (1):1.03a2,bulk≤a1,bulk≤1.15a2,bulk  (1).

In quantum devices with Josephson junctions, the generation of TLS defects and the variation in their characteristics are suppressed. [Solution] A first superconductor film, a second superconductor film, a first insulator film, and a third superconductor film, each having a cubic crystal structure, are sequentially formed by epitaxial growth on the (100) or (111) plane of a substrate having a cubic crystal structure. The second superconductor film, the first insulator film, and the third superconductor film are patterned to form a stack including the second superconductor film, the first insulator film, and the third superconductor film. The first superconductor film is patterned using the stack as a mask. After patterning the first superconductor film, the side surfaces of the stack are wet-etched. A second insulator film is formed to cover the wet-etched side surfaces of the stack. After forming the second insulator film, a fourth superconductor film is formed in contact with the third superconductor film. The stack forms a Josephson junction, and the first superconductor film has a lattice constant between that of the substrate and that of the second superconductor film.

The resent invention is related to a method of manufacturing a semiconductor material comprising group III-V materials grown on a (111)Si substrate, wherein a lattice constant of respective layers is adjustable bringing the lattice constant of the material close to or between the lattice constant of GaAs, GaSb, InAs, InSb and / or InP.

This invention provides an antimonide HEMT structure, an epitaxial structure, and a method for preparing the same. By forming InSb channel layers on both sides of an InAs channel layer, the InSb material, due to its higher lattice constant than InAs and GaSb, exerts tensile stress on the InAs and GaSb layers on either side during growth. This improves the flatness of the interfaces between the InSb and InAs layers, and between the InSb and GaSb layers, and effectively reduces dislocation density, thereby increasing the electron mobility of the quantum well. Simultaneously, inserting a GaSb layer between the InSb and AlSb layers effectively prevents the high-temperature growth of the AlSb layer from affecting the precipitation of In atoms in the InSb and InAs layers. Furthermore, the lattice constant mismatch between the GaSb and AlSb layers is very small, further reducing dislocations and improving the quality of the active layer. Additionally, the InAs composite channel layer structure can form a stepped square quantum well, effectively increasing the concentration of 2DEG.