37results about How to "High photodamage threshold" patented technology

The invention discloses a two-dimensional stratified material saturable absorber device which comprises a substrate. The substrate is a high reflection mirror plated with a back electrode, a dielectric layer and a two-dimensional stratified saturable absorption material are arranged on the high reflection mirror in sequence, an electrode is arranged on the two-dimensional stratified saturable absorption material in an evaporation mode, a voltage source is arranged between the electrode and the back electrode, an optical fiber pigtail is arranged above the two-dimensional stratified saturable absorption material, and the saturable absorption device is attached to the optical fiber pigtail. According to a method, the advantages of a two-dimensional stratified saturable absorber are inherited, such as high performance, low manufacturing cost and easy combination, and CW light and Pulse light can be switched over fast by adjusting grid voltages and freely adjusting the starting threshold value of a laser locking mold.

The invention relates to a three-dimensional measurement method for high-power laser body damage of a KDP (Potassium Dihydrogen Phosphate) crystal. The method substantially comprises the following steps of placing the KDP crystal to be measured into a detection optical path of a digital hologram interferometric device, and detecting a phase distribution outline of body damage in the crystal, i.e. a two-dimensional phase distribution image; carrying out angle scanning on the crystal to be measured, carrying out Fourier transform on the two-dimensional phase distribution image obtained from each angle sampling point, and constructing a three-dimensional phase distribution appearance of the body damage through the Fourier transform. The three-dimensional fine structure of the body damage can be utilized as an important parameter for qualitatively describing laser damage characteristics, and become a key environment correlated with laser damage macroscopic characteristics and micromechanisms and has important application to exploration of a KDP / DKDP (Deuterated Potassium Dihydrogen Phosphate) crystal laser damage mechanism and improvement of a laser damage threshold.

The invention relates to a vector light field converter and a polarized light converting method. The vector light field converter is formed by an optical crystal device and / or a wave plate, wherein the crystal length of the optical crystal device is in spiral change, thus a polarization direction passing through the optical crystal can be subjected to rotation, the radial polarized light output can be obtained, the conversion from the radial polarization to the angular polarization can be realized when a half of the wave plate is placed at the back part of the optical crystal device, and the angular polarized light output can be obtained. The vector light field converter disclosed by the invention has the advantages that the cost is low, the converting efficiency is high, the light damage threshold is high, and the like. The vector light field converter and the polarized light converting method, disclosed by the invention, have important application prospect in optics respects such as quantum optical communication, cold atom trapping, dynamic optical storage, quantum computing and material processing.

The invention discloses a graphene-based brand-new reflective type saturable absorber and a preparation method. The obtained saturable absorber comprises a saturable absorption layer, a reflective film layer and a substrate layer. The preparation method comprises the steps as follows: plating a gold film on a graphene thin film growing on a copper foil, reversing the gold film to face downward, binding with a silicon substrate the upper surface of which is plated with the gold film, contacting a smooth optical fiber end surface and graphene smoothly, and fixing and packaging the optical fiber and the absorber together. As the saturable absorber, the graphene has the advantages of being low in saturation strength, ultrafast in recovery time, adjustable in modulation depth, unrelated with wavelength, low in cost and the like, and by combining the specific structure advantage of the reflective type saturable absorber, the novel saturable absorber which is practical, simple and high-efficiency, stable in working property, high in optical damage and convenient for large-scale production can be realized.

The invention discloses a novel cone lens generating a single bottle beam, which is an axicon, wherein a concave circular truncated cone structure is formed at the bottom of the axicon, and the bottom angle of the circular truncated cone structure is less than that of the axicon. The novel cone lens can acquire the single bottle beam through one element, has the advantages of relatively easy element processing, simple structure, high conversion efficiency and high photo damage threshold, and provides a novel concise and efficient way for acquiring the bottle beam; furthermore, the size of the single bottle beam can be adjusted by adjusting the size of the bottom angle or the inner bottom radius of the circular truncated cone structure. In practical application, the novel cone lens can be used as laser conduits, optical tweezers, optical wrenches and other tools, and can be used for confining microscopic particles, neutral atoms, molecules, biological cells and the like by laser, thus has special significance in life science and nano-technology, in particular single-plane and multi-plane manipulation on microparticles.

The invention provides a preparation method of a two-dimensional black arsenic-phosphorus nano material, which comprises the following steps: preparing a bAsP crystal: providing ash arsenic, red phosphorus and a mineralizing agent, putting the components into a sealed vacuum quartz tube, heating the vacuum quartz tube to 735-765 DEG C, keeping the temperature for 1.5-2.5 hours, cooling the vacuumquartz tube to 480-520 DEG C within 10 hours, and keeping the status for 2-4 hours, and further cooling the vacuum quartz tube to 120-180 DEG C within 10 hours, and finally cooling the quartz tube toroom temperature to obtain the b-AsP crystal; preparation of the two-dimensional b-AsP nano material: dissolving the b-AsP crystal in a dispersion liquid, and sequentially carrying out probe ultrasonic treatment and water bath ultrasonic treatment to obtain the two-dimensional bAsP nano material. The preparation method of the two-dimensional black arsenic-phosphorus nano material has the advantages of simple process, simple equipment, high yield and the like. The invention also provides application of the preparation method of the two-dimensional black arsenic-phosphorus nano material.

The invention relates to an optical lens and provides a lens capable of directly producing an annular hollow focus beam. The lens capable of directly producing an annular hollow focus beam comprises a convex lens having a beam input surface and a beam output surface. A concave cavity is provided at the center of the beam output surface of the convex lens. The depth of the concave cavity is much smaller than the thickness of the central axis part of the convex lens, the aperture of the concave cavity is much smaller than the diameter of the convex lens, and the curvature of the surface of the concave cavity is much larger than that of the beam input surface of the convex lens. An annular hollow focus beam can be obtained by focusing a parallelly-incident Gaussian beam and a focus spot can reach the micron level, so the very high power density and light conversion efficiency are achieved. In addition, the number of optical components is reduced, the practical application cost of the annular hollow focus beam is significantly reduced and the difficulty in system installation and debugging is effectively decreased, so the lens of the invention is applicable in various general occasions.

The invention discloses a novel lithium niobate optical waveguide wafer. The novel lithium niobate optical waveguide wafer comprises a lithium niobate wafer and an optical waveguide, wherein the lithium niobate wafer is an optical-level wafer, and the crystal orientation is one of X-cutting Y-transmission or Z-cutting Y-transmission or X-cutting Z-transmission or Y-cutting Z-transmission; and theoptical waveguide is a zinc oxide diffusion lithium niobate optical waveguide. In addition, the invention also provides a preparation method of the two lithium niobate optical waveguide wafers. The zinc oxide diffusion lithium niobate optical waveguide provided by the invention has the following advantages that (1) the two polarization modes of TE and TM can be simultaneously transmitted, a lightdamage threshold value higher than that of the titanium diffusion optical waveguide is achieved, and the wafer is more suitable for being applied to a light transmission system requiring relatively high optical power transmission; (2) the relatively high light damage threshold value is achieved, the two polarization modes can be transmitted at the same time, and a phenomenon that one of the polarization modes is filtered is avoided; and (3) the preparation process is simple, the rate of finished products is high, the cost is low, and the wafer is more suitable for batch production.

The invention provides a method for preparing a KTP nonlinear runway type micro-ring resonator. The method comprises six steps of KTP wafer treatment, ion implantation, electron beam exposure, subsequent treatment, ion etching treatment and final treatment. Preparation of a film-shaped waveguide structure similar to an on-chip lithium niobate film material is prepared through one procedure of ion implantation. The production process is greatly simplified, the time is shortened, and the cost is significantly reduced. Compared with an existing lithium niobate nonlinear micro-ring resonator, the KTP nonlinear micro-ring resonator prepared by the method has the advantages that the light damage threshold is higher, the output power of nonlinear variable-frequency light can be increased to milliwatt magnitude from microwatt, the method is suitable for the situation that input and output optical signals are pulse laser, and ion injection, electron beam exposure, metal evaporation deposition coating and reactive ion etching are relatively mature micro-nano machining technologies, so that the method has good operability and repeatability.

The invention relates to a BBO crystal with a special chamfered angle, a triple-frequency optical converter and a working method of the triple-frequency optical converter. When the fundamental-frequency optical wavelength is gradually increased from 750 nm to 1200 nm, the phase-matching angle theta of the BBO crystal is gradually decreased from 42.1-52.1 degrees to 24.2-34.2 degrees, and the azimuth angle phi of the BBO crystal is 6-16 degrees; the length of the BBO crystal in the optical direction is 6-14 mm. The single BBO crystal can achieve high-efficiency cascade triple frequency of nearinfrared laser of wave bands, and ultraviolet or purple laser is output. The prepared triple-frequency optical converter has the advantages of being low in cost, high in anti-optical-damage threshold,wide in available band, large in effective nonlinear optical coefficient, large in output energy, high in conversion efficiency and the like, and the overall performance of the triple-frequency optical converter is superior to that of similar components made from ADP or KDP or GdxY1-xCOB crystals.

The invention provides an optical fiber coupling-based high-polarization extinction ratio waveguide polarizer and a manufacturing method thereof. The invention aims to solve the problems of the high insertion loss and low optical power threshold of a lithium niobate annealed proton exchanged waveguide-based waveguide polarizer and further improve the polarization extinction ratio of such kind of devices. According to the optical fiber coupling-based high-polarization extinction ratio waveguide polarizer and the manufacturing method thereof of the invention, a magnesium oxide doped lithium niobate crystal or a near-stoichiometric lithium niobate crystal is adopted, so that the increase of the optical power threshold of the device can be realized; an anti-proton exchanged waveguide is prepared in the magnesium oxide doped lithium niobate crystal or near-stoichiometric lithium niobate crystal, so that the insertion loss of the waveguide is decreased; and the back surface of the magnesiumoxide doped lithium niobate crystal or near-stoichiometric lithium niobate crystal is slotted and is coated with a light absorbing material, so that the polarization extinction ratio of the waveguidepolarizer can be further improved.

The present invention relates to a ferrule member. The ferrule member includes a ferrule shell, which has an optical fiber lead-through channel. Optical fiber is inserted into the optical fiber lead-through channel. The optical fiber is the single-mode optical fiber with an enlarged mode field diameter; and the mode field diameter at a butting end is more than 9[mu]m. Compared with the ordinary optical fiber, the influence of butt deviation and dust on the optical fiber with the enlarged mode field diameter is less; the optical coupling efficiency and the optical damage threshold of the optical fiber end face are significantly improved; and the transmission loss between the ferrule members is reduced.

The invention discloses a poling method for a relaxor ferroelectric single crystal as a nonlinear optical material. The method comprises an annealing process and a polarization process; the relaxor ferroelectric single crystal comprises a binary (1-x)Pb(Mg1 / 3Nb2 / 3)O(3-x)PbTiO3 system and a ternary (1-x-y)Pb(In1 / 2Nb1 / 2)O(3-x)Pb(Mg1 / 3Nb2 / 3)O(3-y)PbTiO3 system; according to the annealing process, the relaxor ferroelectric single crystal after grinding and polishing is subjected to annealing treatment in atmosphere, stress caused by machining is removed, and spontaneous strain produced in a ferroelectric phase forming process is released to the great degree through quite slow cooling, so that the probability of cracking caused by electrically induced domain rotation in the crystal poling process is reduced. Besides, after an electric field is removed, a remaining depolarization field can be induced to form a nanometer domain structure. In order to guarantee formation and stability of a single-domain structure, the remaining depolarization field can be compensated by bulk shielding effect formed through electrode injection, the relaxor ferroelectric single crystal with high poling performance and stable performance is obtained, and the material has the characteristics of small half-wave voltage, large photo damage threshold, large electro-optic coefficient and the like and is far better than BBO, KTP, LN and other materials.

The invention discloses a concave axicon capable of producing long distance non-diffraction beams. The concave axicon capable of producing long distance non-diffraction beams is provided with an axicon, wherein a cone angle of the axicon is gamma, an undersurface radius of the axicon is a, and an refractive index of the axicon is n. The axicon is divided into a cylinder part and a circular cone part along an axis direction, one end in which the cylinder part and the circular cone part are adjacent is the inside, the other end is the outside, and the outside undersurface of the cylinder part is in a concave spherical surface shape, wherein a center of the concave spherical surface shape is the axis of the axicon, and a curvature radius of the concave spherical surface shape is R. The long distance non-diffraction beams can be achieved through a single element, the problems that a cone angle of a traditional axicon is small and processing is hard are overcome, the concave axicon capable of producing the long distance non-diffraction beams has the advantages of being easy in element processing, simple in structure, high in transfer efficiency, and high in optical damage threshold value, a concise and effective new way is provided for acquiring the long distance non-diffraction beams, and in addition, non-diffraction distance of the non-diffraction beams can be adjusted through adjusting radii of incident beams and a size of the curvature radius of the undersurface of the concave axicon.

The invention belongs to the field of optics and concretely relates to a preparation method of a silica-base broadband saturable absorber device. The preparation method mainly includes the following steps: firstly, preparing broadband saturable absorber sol, and secondly, dispensing the prepared broadband saturable absorber sol in a D type zone of a D type fiber, and then obtaining a broadband saturable absorber device after the sol stands to become gel. A sol-gel method is adopted to prepare broadband saturable absorbers, and the absorbers are uniformly distributed in silica sol to effectively isolate the air and form a great protection substrate, so oxidation is prevented, a light injury threshold is increased, and the use stability is improved. The broadband saturable absorbers can be used for an all-fiber evanescent wave mode locked fiber laser and can greatly reduce insertion loss, so unsaturated loss of the broadband saturable absorber device is reduced. The prepared broadband saturable absorbers are convenient to use and convenient for industrial popularization.

The invention discloses a terbium-containing borate compound. The chemical formula of the terbium-containing borate compound is Rb2LiTbB2O6. The invention also discloses a polycrystalline compound ofthe terbium-containing borate compound, an optical crystal, and a preparation method and application of the optical crystal. The polycrystalline compound can be used as a fluorescent powder matrix, and the optical crystal can be used as a magneto-optical crystal. The terbium-containing borate compound is simple in synthesis and low in cost, grows easily, and has important economic value and scientific research value in the field of solid-state illumination and magneto-optical materials.

The invention relates to a communication signal source, in particular to a photonic crystal fiber laser. The photonic crystal fiber laser comprises a pump light source, an optical coupler and a photonic crystal fiber, wherein the optical coupler enables light emitted by the pump light source to be coupled in the photonic crystal fiber, and light reflection parts are arranged at two ends of the photonic crystal fiber to form an optical resonant cavity. The communication signal source is characterized in that the photonic crystal fiber is provided with a rare earth adding core where rare earth elements are added, a covering layer formed around the rare earth adding core and a plurality of through holes formed on the covering layer. Excitation light enters from the end of the covering layer, the rare earth elements are excited to output high-power laser oscillation light, and the through holes are filled with a liquid material with the dielectric constant ranging from 1.6 to 2.8.

The invention discloses a rare earth borate crystal material, and a preparation method and application thereof. The chemical formula of the rare earth borate crystal material is Rb2LiGdxLn1-xB2O6, and the rare earth borate crystal material belongs to an orthorhombic crystal system and a pbcm space group; and 0.01 <= x <= 1, and Ln is a rare earth element. A rubidium-containing compound, a lithium-containing compound, a gadolinium-containing compound, a rare earth element-containing compound and a boron-containing compound are used as raw materials, and a high-temperature solid-phase synthesis method or a fluxing agent method is adopted for preparation. The rare earth borate crystal material provided by the invention has the advantages of stable physical and chemical properties, difficulty in deliquescence in air and the like.

The invention relates to a saturable absorber for a fiber laser and a preparation method thereof. The saturable absorber is a transmission-type tapered saturable absorber, comprising a core (101), a cladding (102), Coating layer (103) and heterojunction layer. Layered graphene and Bi obtained by exfoliating the liquid phase 2 Te 3 The solution can be obtained by attaching to the tapered region of the tapered single-mode fiber by light adsorption. Compared with the prior art, the invention has the advantages of high damage threshold, simple structure, bidirectional transmission fiber laser capable of carrying high power, and the like.

The invention relates to a three-dimensional measurement method for high-power laser body damage of a KDP (Potassium Dihydrogen Phosphate) crystal. The method substantially comprises the following steps of placing the KDP crystal to be measured into a detection optical path of a digital hologram interferometric device, and detecting a phase distribution outline of body damage in the crystal, i.e.a two-dimensional phase distribution image; carrying out angle scanning on the crystal to be measured, carrying out Fourier transform on the two-dimensional phase distribution image obtained from each angle sampling point, and constructing a three-dimensional phase distribution appearance of the body damage through the Fourier transform. The three-dimensional fine structure of the body damage canbe utilized as an important parameter for qualitatively describing laser damage characteristics, and become a key environment correlated with laser damage macroscopic characteristics and micromechanisms and has important application to exploration of a KDP / DKDP (Deuterated Potassium Dihydrogen Phosphate) crystal laser damage mechanism and improvement of a laser damage threshold.

The invention discloses a novel cone lens for generating Bottle beams with the periodicity, which consists of an axis pyramid and a frustum structure glued at the bottom of the axis pyramid; the lower bottom surface of the frustum structure is glued with the bottom surface of the axis pyramid; and the radius of the lower bottom surface of the frustum structure is larger than that of the upper bottom surface of the frustum structure. The novel cone lens can obtain a plurality of Bottle beams with the recurrence periodicity through a single component and adjust the dimension and the recurrence periods of the plurality of generated Bottle beams through controlling a bottom angle of the frustum structure and the radius of the upper bottom. Compared with the conventional method for generating the bottle beams, the novel cone lens has the advantages of simple structure, high conversion efficiency and high light damage threshold value, and the component is simple to process. The novel cone lens provides a brief and effective new approach for obtaining the Bottle beams and has the special significance for the multi-layer operation and control of particles.

The invention discloses a broadband strong-field terahertz source based on a silicon carbide single crystal. The broadband strong-field terahertz source comprises a femtosecond pulse laser source, a wavefront tilting system, a silicon carbide wafer and a coupling output end. The femtosecond pulse laser source part comprises a femtosecond laser and a plane mirror, the wavefront inclination system part comprises a reflection grating, a half-wave plate and a telescope imaging lens group, femtosecond laser is normally incident to a silicon carbide wafer after passing through a wavefront inclination system, terahertz pulse radiation is generated in the wafer in a light rectification mode, and the terahertz pulse radiation is transmitted to the femtosecond laser; terahertz pulse radiation is coupled and output through the triangular prism silicon prism at the coupling output end. Wherein the thickness of the silicon carbide wafer is 0.5-6 mm, the wavefront inclination angle of pulses in the wafer is 31.5-38 degrees, three cylindrical surfaces of the triangular prism silicon prism are subjected to optical polishing treatment, the cutting angle of the terahertz output surface of the triangular prism silicon prism is 31-32 degrees, and the input surface of the triangular prism silicon prism completely covers and is attached to the output surface of the silicon carbide wafer through an optical contact method.

The invention discloses a two-dimensional stratified material saturable absorber device which comprises a substrate. The substrate is a high reflection mirror plated with a back electrode, a dielectric layer and a two-dimensional stratified saturable absorption material are arranged on the high reflection mirror in sequence, an electrode is arranged on the two-dimensional stratified saturable absorption material in an evaporation mode, a voltage source is arranged between the electrode and the back electrode, an optical fiber pigtail is arranged above the two-dimensional stratified saturable absorption material, and the saturable absorption device is attached to the optical fiber pigtail. According to a method, the advantages of a two-dimensional stratified saturable absorber are inherited, such as high performance, low manufacturing cost and easy combination, and CW light and Pulse light can be switched over fast by adjusting grid voltages and freely adjusting the starting threshold value of a laser locking mold.

The invention discloses a novel axicon capable of generating multiple Bottle beams. The axicon is characterized in that on the basis of a traditional axicon, a part adjacent to the top end is of a spherical structure. According to the novel axicon, multiple Bottle beams can be generated by virtue of a single component; the novel axicon has the advantages of simple component structure, high conversion efficiency, high light loss threshold and energy concentration; the generated multiple Bottle beams are concentrated in energy, so that the particle confinement degree can be improved; a concise and effective new way is provided for acquiring multiple Bottle beams; and the novel axicon has guidance significance to particle control such as particle confinement.

The invention relates to an optical parametric oscillation laser based on wide-band-gap semiconductor silicon carbide crystals. The optical parametric oscillation laser sequentially comprises an excitation source, an input mirror, the semiconductor SiC crystals and an output mirror. The semiconductor SiC crystals are cut in the phase position matching direction of optical parametric oscillation of the semiconductor SiC crystals, medium membranes which allow much excitation light, much signal frequency light and much idler frequency light to penetrate through are plated on light-permeable faces respectively, the excitation source is an all-solid-state pulsed laser, medium membranes which allow much excitation light to penetrate through and allow much frequency light and much idler frequency light to be reflected are plated on the two light-permeable faces of the input mirror respectively, and a medium membrane which allows much frequency light to be reflected and allows idler frequency light to partially penetrate through is plated on the input mirror. The wide-band-gap semiconductor silicon carbide crystals are used as a non-linear optical medium, therefore, the optical parametric oscillation laser ranging from 1.28 micrometers to 6 micrometers are output, the output energy is high, the structure is simple, and the penetrating range is continuous and adjustable.

The present invention relates to artificial crystal, and is especially one kind of self-frequency doubling laser crystal material Yb3+:Gd1-xYxCa4O(BO3)3 and its preparation process. The crystal belongs to the moniclinic system, has space group Cm; has the crystal cell parameter of a=8.080 angstrom, b=16.014 angstrom, c=3.539 angstrom, beta=101.18 deg, and V=449.0 cubic angstrom; and refractive index of 1.69. The monocrystal is grown in Czochralski process at the grown temperature of 1481-1550 deg.c, pulling rate of 0.5-3 mm / hr, crystal rotation speed of 15-40 rpm. The monocrystal has high quality and large size.