130 results about "Third order nonlinear" patented technology

Servo control using ferromagnetic core material and electrical windings is based on monitoring of winding currents and voltages and inference of magnetic flux, a force indication; and magnetic gap, a position indication. Third order nonlinear servo control is split into nested control loops: a fast nonlinear first-order inner loop causing flux to track a target by varying a voltage output; and a slower almost linear second-order outer loop causing magnetic gap to track a target by controlling the flux target of the inner loop. The inner loop uses efficient switching regulation, preferably based on controlled feedback instabilities, to control voltage output. The outer loop achieves damping and accurate convergence using proportional, time-integral, and time-derivative gain terms. The time-integral feedback may be based on measured and target solenoid drive currents, adjusting the magnetic gap for force balance at the target current. Incorporation of permanent magnet material permits the target current to be zero, achieving levitation with low power, including for a monorail deriving propulsion from the levitation magnets. Linear magnetic approximations lead to the simplest controller, but nonlinear analog computation in the log domain yields a better controller with relatively few parts. When servo-controlled solenoids provide actuation of a pump piston and valves, electronic LC resonance measurements determine liquid volume and gas bubble volume.

Servo controlled solenoids provide actuation of a pump piston and valves, and electronic LC resonance measurements to determine liquid volume and gas bubble volume. Third order nonlinear servo control is split into nested control loops: a fast nonlinear first-order inner loop causing flux to track a target by varying a voltage output, and a slower almost linear second-order outer loop causing magnetic gap to track a target by controlling the flux target or the inner loop. The inner loop uses efficient switching regulation, preferably based on controlled feedback instabilities, to control voltage output. The outer loop achieves damping and accurate convergence using proportional, time-integral, and time-derivative gain terms. The time-integral feedback may be based on measured and target solenoid drive currents, adjusting the magnetic gap for force balance at the target current.

The invention discloses sodium borosilicate glass doped with In2S3 quantum dots and a preparation method thereof. According to the sodium borosilicate glass doped with the In2S3 quantum dots, the In2S3 quantum dots are uniformly doped into sodium-borosilicate-based glass, and the sodium-borosilicate-based glass contains the following ingredients in percentage by mass: 5-15% of Na2O, 15-30% of B2O3 and 55-80% of SiO2; and the doped amount of the In2S3 quantum dots is 0.1-5.0% of the mass of the sodium-borosilicate-based glass. The sodium borosilicate glass doped with the In2S3 quantum dots is prepared in a manner that a sol-gel method is combined with atmosphere control, has excellent third-order nonlinear optical performance and heat stability, and has high light transmittance in visible-infrared regions, thereby being an important candidate material which is expected to produce high-speed full-light logic devices.

The present invention applies microprocessing technique to utilize high refractive index of semiconductor material to prepare high quality of two-dimensional photon crystal with defect state and optical switch can be realized by utilizing high third order-nonlinear polarizability and quick response time of semiconductor material. The produced optical switch can be widely used in field of optical communication and optical computer.

The invention provides an heralded multi-wavelength single photon source generating system based on a micro-ring cavity structure. The system comprises a pumping unit, an entangled photon pair generating unit, a wavelength division multiplexing unit and a heralding unit. A pulse laser of the pumping unit emits lasers, wherein the communication waveband of the pluse laser is 1550 m, and the pulse width near the wavelength of the lasers is t; the lasers form time-entangled pulse pairs with the time interval of T (T > t) through a Mach-Zehnder interferometer; the entangled pulse pairs are coupled into a micro-ring cavity with a high Q value of the entangled pair generating unit through optical fibers, and due to a third-order nonlinear action in the micro-ring cavity, time-entangled pumping optical pulses are converted into a large number of controllable multi-wavelength time-entangled photon pairs; the time-entangled photon pairs with different wavelengths are emitted from different outlets through the wavelength division multiplexing unit to reach the announcement unit; a plurality of single photon detectors of the announcement unit detect the responding conditions of idle light according to corresponding channels to herald the generation of signal single photons, and therefore the multi-wavelength single photons with communication wavebands are emitted.

A measuring device for femtosecond laser pulse shapes structurally comprises a four-small pore plate, a medium delay piece, a reflector with partial area coated, a paraboloid reflector, a third-order nonlinear medium piece, a small-hole aperture, a focusing lens, a concave reflector and a high resolution spectrograph. And an output end of the high resolution spectrograph is connected with an input end of a computer. The measuring device for femtosecond laser pulse shapes has the advantages of simple and practical structure, convenience for adjusting, quickness in data collection and data processing and suitability for measuring and real-time monitoring of pulse widths and pulse shapes of femtosecond lasers of different pulse widths and wavelengths.

The invention discloses a hyperbranched metal phthalocyanine oligomer containing an imide structure and a preparation method thereof and belongs to the technical field of high polymer materials and preparation thereof. The invention aims at solving the problems that existing hyperbranched phthalocyanine can obviously lower thermal decomposition temperature and conjugation degree of a phthalocyanine polymer and an adverse effect is produced to properties of a material. The preparation method comprises the following steps of: carrying out reaction on 4-amino phthalonitrile and acid anhydride monomers to obtain a tetracyano-terminated monomer containing the imide structure, and then carrying out polymerization reaction to obtain the hyperbranched metal phthalocyanine oligomer containing the imide structure. The prepared hyperbranched metal phthalocyanine oligomer containing the imide structure is obviously improved in third-order nonlinear optical property and thermal stability, integrates a high-performance structure and a functional polymer into a whole and is hopeful to become an ideal material for optical devices.

The invention belongs to a Zn (II) coordination polymer as well as a preparation method and an application thereof. The chemical formula of the Zn (II) coordination polymer is [Zn 12(1,4-NDC )12(TPY )12*2H2O]n, wherein 1,4-NDC is 1,4-naphthalenedicarboxylic acid, TPY is 4-phenyl-2,2':6',2''-terpyridine. The Zn (II) coordination polymer as well as the preparation method and the application thereof have the advantages that the preparation method is simple and easy to operate, the product yield is high, the product can be stable at the temperature of 130 DEG C or lower and has high third-order nonlinear optical reverse saturable absorption performance, the third-order nonlinear susceptibility Chi<3> of a pure material is 6.46*10<-8> esu, and the Zn (II) coordination polymer can be applied to optical limiting and laser protection devices.

The coherent imaging method of 4f position based on the Michelson's interferometer is the nonlinear refractive method of 4f position coherent imaging measuring medium based on the Michelson's interferometer. It can solves the problem of data treating bother, nonlinear absorption of traditional 4f coherent imaging technology and the small deform range, high request for stability and complex data treating of Mach-Zehnder interference. The method is composed of the processes: one: starting and adjusting the device; two: collecting the image without image; three: collecting the linear image; four: collecting the nonlinear image; five: computing the linear penetrant ratio; six: computing the nonlinear phase movement; seven: computing the third-order nonlinear refraction coefficient.

The invention tellurate glass and a preparation method is disclosed, among which the basic compositions of the glass are 65-85 mol percent of TeO2, 0-20 mol percent PbO, 2-8 mol percent of PbF2, 0-10 mol percent of Bi2O3, 0-15 mol percent Nb2O5. , Being prepared through a common melting method. In the melting process, preparation technologies like stirring, putting into dry nitrogen and clarification are adopted to ensure that [OH-] mass in the glass compositions can be effectively removed. The glass material is characterized by good materialization stability, favorable fiber-forming, high third-order nonlinear susceptibility, small dispersion slope and so on; the preparation process has simple and easy operation and low cost. The invention is applicable to use optical fiber matrix material in super short pulser source of optical communication.

The present invention discloses application of a multi-channel optical nonlinearity measurement technology to measure the third-order nonlinear refraction coefficient of a medium. According to the present invention, with numerical simulation, a linear relationship is formed in the range of 0-0.65; in the experiment, the results of a sample to be measured and a standard sample can be directly measured, and by using the linear range, the third-order nonlinear refraction coefficients of a plurality of samples to be measured can be measured through the measuring, such that the complex fitting calculation required by the original single-4f system is avoided; and the experiment results verify that the method of the present invention is correct.

Apparatuses and methods for supercontinuum generation using a laser beam and a plurality of condensed state transparent plates are presented. As an example, plate material to be used for one of the plurality of plates is determined. A thickness of the one of the plurality of plates is also determined. An allowable laser intensity of the laser beam is then determined to be λ / (2n0n2L), where λ is the central incident wavelength in vacuum, n0 is the linear refractive index, n2 is the third-order nonlinear coefficient. A location of a next plate is then determined to be a distance downstream from the one of the plurality of plates where a laser intensity of the laser beam returns to a value of the determined allowable laser intensity.

Apparatuses and method for real-time measuring ultrashort pulse shape and pulse width. Transient-grating effect on a transparent optical medium is used to generate a reference beam. A black plate with four equal-sized holes divides the incoming laser beam into four beams, one of which is attenuated and introduced an appropriate time delay relative to the other three. The four laser beams pass through a concave mirror and are focused onto a nonlinear transparent optical medium. The three beams without attenuation are used to generate a transient-grating light in the transparent medium. The transient-grating light is collinear and overlapped with the fourth attenuated beam. According to the third-order nonlinear effect, the transient-grating light has a broader spectral bandwidth and more smooth spectrum phase with respect to the incident laser. By measuring the spectral interference, the spectrum and spectral phase may be retrieved by spectral interferometry.

The invention discloses a method for constructing a cascade superlattice mode-locked laser. In the method, cascade optical superlattices are used as nonlinear crystals, the cascade second-order nonlinear effect of two or more sections of domain-structure cascade optical superlattices is utilized to generate equivalent third-order nonlinear effect, and the nonlinear crystals are enabled to work atphase matching points by controlling the temperature of the optical superlattices through controlling the temperature of a furnace; a resonant cavity is adjusted to reach the requirement of nonlinearfrequency conversion; and the position of a diaphragm in the resonant cavity of a laser is set to ensure that the radius of facula at the position of the diaphragm is reduced along with the incrementof pumping power, the diaphragm realizes nonlinear loss modulation and spatial phase modulation is converted into intensity modulation, thus realizing mode locking laser output. The method can obtaina bigger non-linear loss coefficient, thereby being capable of supporting mode locking operation with larger stable area range, realizing self-starting of the mode-locked laser and improving the facula quality, stability and the optical to optical conversion efficiency.

The invention relates to a polyamide film, and a production method and an application thereof, and concretely relates to a triphenylamino group-containing polyamide film, and a production method and an application thereof. The purpose of the invention is to solve the problems of low solubility in organic solvents, difficult film formation processing and low photoelectrochromic response sensitivity of present polyamide. The structural formula of the triphenylamino group-containing polyamide film is shown in the specification. The production method comprises the following steps: 1, carrying out a polymerization reaction; and 2, carrying out curing film formation to obtain the triphenylamino group-containing polyamide film. The triphenylamino group-containing polyamide film can be applied in electrochromic materials, photochromic materials, hole transporting materials, third order nonlinear materials, anti-counterfeit and camouflage materials and display materials as a photoelectric material. The triphenylamino group-containing polyamide film can be obtained in the invention.

The invention discloses a method and device for fabrication of a frequency degenerate multi-photon entangled source using an integrated waveguide. The method comprises the following steps that (1), two pulsed light beams with different frequencies are obtained; (2), intensity of the two pulsed light beams is amplified; (3), relative time delay of the two pulsed light beams is adjusted to synchronize the two pulsed light beams, and the polarization directions of the two pulsed light beams are adjusted to be consistent; and (4), the two pulsed light beams are introduced into a Sagnac loop, eachpulsed light beam is divided into two beams of light orbiting in different directions and generates photon pairs under the spontaneous four-wave mixing of a third-order nonlinear medium, the pulsed light beams returning from different directions are combined and elicited from the Sagnac loop, and the frequency degenerate multi-photon entangled source is obtained. The method has higher stability and expansibility, can achieve complexity which is difficult to achieve in space optics, and has a high application prospect.

The invention provides a virtual synchronous motor control method with adaptive instruction filter inversion. The method comprises the following steps: a third-order nonlinear state space model is built; and a controller is acquired according to the third-order nonlinear state space model. Through modeling of an ideal synchronous motor rotor equation and a torque part, an adaptive instruction filter inversion controller is designed, smooth switching of a system grid-connected process can be realized, power fluctuation is reduced, and practical engineering application is facilitated.

The coherent imaging device of 4f position based on the Michelson's interferometer is the third-order nonlinear refractive index used to measure the nonlinear photo medium. It can solves the problem of data treating bother, nonlinear absorption of traditional 4f coherent imaging technology and the small deform range, high request for stability and complex data treating of Mach-Zehnder interference. The first linear attenuating sheet, the first beam splitter, the second aperture diaphragm and second all-mirror are set at the central axis of the laser emitting mouth. the right side of low emitting point on first beam splitter is 45degree with the central axis of laser emitting mouth. The second linear attenuating sheet, the second convex, the first convex, the first beam splitter, the first aperture diaphragm and the first all-mirror are set at the central axis of the CCD camera image collecting side; the lower side of right emitting point on first beam splitter is 45degree with the central axis of image collecting side.

The invention discloses a method of simulating the specific nonlinear wave sequence. The method includes preprocessing of the ocean measured wave sequence, accurate solution of the nonlinear dispersion relation and automatic generation of wave machine driving signals. According to the method, the observed ocean wave sequence can be automatically processed, the wave sequence obtained through oceanobservation is converted into the frequency, the corresponding amplitude and the phase information required for laboratory simulation waves according to the Froude number similarity criterion throughutilizing Fourier transform; the third-order nonlinear irregular wave interaction theory is utilized to rapidly calculate the dispersion relation of complex multi-frequency waves through the iterativecalculation method, generally, wave number accuracy of wave components can be calculated to one thousandth within ten iteration steps, and problems of low precision and long time for directly solvingthe nonlinear dispersion relation are solved.

The invention discloses a phase diaphragm (2) capable of measuring optical nonlinearity of material, comprising a phase object (13), wherein the phase delay between the phase object (13) and the phase diaphragm (2) is Pi / 2; the phase object (13) is a symmetrical square. The invention can effectively measure and distinguish the size and symbol of the third-order nonlinear refraction coefficient of a medium without influencing the measuring sensitivity.

The invention discloses a preparation method of a narrow-bandgap polypyrrylarylenemethine photoelectric functional polymer material, belonging to a synthesis technology of a conjugated polymer material. The preparation method comprises the following processes: reacting 3-butyrylpyrrole with para-tetradecyloxybenzaldehyde under an acidic condition to prepare poly-[(3-butyrylpyrrole)-2,5-di(para-tetradecyloxyphenylmethane)](PBPDTBA); and carrying out further quinonization on the PBPDTBA with tetrachlorobenzoquinone to obtain poly-[(3-butyrylpyrrole)-2,5-di(para-tetradecyloxyphenylmethylene)](PBPDTBE). The prepared polypyrrylarylenemethine can be dissolved in chloroform, benzene and other low-boiling solvents and has fine solubility and film-forming property, the optical bandgap and the electrochemical bandgap are respectively 1.84 eV and 1.60 eV, and the third-order nonlinear optical polarizability measured by the Z-scanning method can be up to 1.22*10<-8>esu.

The invention discloses a method for generating ultra-wideband optical radiation based on a chirp pulse optical parametric oscillator. The method includes as the steps of: determining pump light of acorresponding wave band and corresponding second-order nonlinear crystal according to the wavelength of required ultra-wideband optical radiation; determining the length of the second-order nonlinearcrystal according to the bandwidth of the required ultra-wideband optical radiation, and determining the pulse width of the pump light according to the second-order nonlinear crystal; designing a third-order nonlinear optical parametric oscillator (OPO) to ensure the existence of self-phase modulation (SPM) in the OPO cavity, so as to obtain the spectral broadening. By introducing enough third-order nonlinear effect into the resonant cavity to make the optical parametric oscillator work in the mode of chirped pulse, and precisely controlling the intracavity net dispersion through a dispersionadjusting element in the cavity, the optical parametric oscillator outputs ultra-wideband optical radiation close to the second-order nonlinear crystal phase matching bandwidth.

A system for equalizing pulse to pulse energy of a light beam includes a group of optical devices including an optical device configured to exhibit third order nonlinear properties. Transmission properties of an unequalized light beam passing through the group of optical devices change such that an output intensity of a resulting light beam output from the optical devices is equalized. One example configuration includes a beam splitter, a nonlinear interference filter, a mirror and a beam combiner. A first portion of the light beam that is reflected from the nonlinear interference filter is combined with the light beam such that a resulting combined light beam has equalized output intensity. Another example includes at least first and second prisms having third order nonlinear properties and configured as a beam steering system. A lithography system and a method of equalizing pulse to pulse energy in a light beam are also presented.

The invention discloses a method for inhibiting intermodulation distortion of a microwave photonic system based on carrier band processing. The method comprises a step S1 of establishing a modulation model of the microwave photonic system, a step S2 of analyzing the origin of third-order nonlinear intermodulation distortion to obtain three major intermodulation distortion components, and simultaneously, determining the relation between a carrier band phase shift amount theta and the major intermodulation distortion components, and a step S3 of adjusting the phase shift amount of the carrier band phase to theta so that the three major intermodulation distortion components obtained in the step S1 are cancelled out mutually. The invention also discloses a system for inhibiting intermodulation distortion of the microwave photonic system based on carrier band processing; the system comprises a continuous light source, a polarization control circuit, an intensity modulator, a carrier band processor and a double-tone radial frequency signal generation source. The method and the system have the advantages that no extra distortion needs to be established and the structure is simple, the inhibition of distortion can be completely only by introducing the relatively fixed carrier band phase shift amount, the performance is reliable and stable, and in addition, the advantages of an integrated device can be integrated and the integrated device is taken as the carrier band processor so that the cost can be reduced.

The invention provides a third-order nonlinear optical material, namely a tetrabutyl ammonium fullerene ball and a synthesizing method thereof, which belongs to the field of functional materials. The prior inorganic and organic nonlinear optical materials have the problems of easy deliquescence, poor thermal stability, complicated preparation and the like respectively. The molecular formula of the tetrabutyl ammonium fullerene ball provided by the invention is (NH4)18[(C16H36N)4]24[Mo132O372(H2O)72(CH3COO)30].ca.7NH4CH3COO.ca.173H2O. In the method, after {Mo132} and tetrabutyl ammonium bromide are dissolved in water respectively according to the mass ratio of 1 to 42, and are adjusted by acetic acid respectively until the pH value is between 3.5 and 4.5, the {Mo132} and the tetrabutyl ammonium bromide are mixed to obtain the tetrabutyl ammonium fullerene ball. The third-order nonlinear optical material has the advantages of uneasy deliquescence, high thermal stability, larger nonlinear absorption and non-linear refraction coefficient, self-defocusing property and simple preparation.

The invention discloses a polyether sulphone copolymer with side chains containing porphyrin and a preparation method of the polyether sulphone copolymer, and belongs to the technical field of high polymer material preparation. Porphyrin is a special conjugate macrocyclic compound and has aromaticity, the delocalization degree of pi electrons is quite high, and therefore porphyrin shows a significant third-order nonlinear optical effect. Monoamino porphyrin is introduced into side chains of polyether sulphone containing carboxyl under the chemical bonding action, and thus the polyether sulphone copolymer with side chains containing porphyrin is successfully prepared. The polyether sulphone copolymer retains the excellent thermal properties and mechanical properties of polyether sulphone and is also endowed with novel optical properties. The prepared polyether sulphone copolymer with side chains containing porphyrin integrates the constitutive property of a high-performance polymer and the functionality of porphyrin, and is expected to serve as a laser protection material for protecting human eyes and precise optical sensors.

The invention provides a waveguide chip for realizing nonlinear frequency conversion based on a coupling waveguide. The waveguide chip comprises: sequentially arranged pumping laser manipulation regions I, a waveguide coupling region II for generating parametric light and entangled photons, and a region III for manipulating converted light; a coupling waveguide region is arranged in a waveguide optical path region II, and the length of the coupling region should be large enough to ensure that an optical field can be coupled back and forth for multiple times; the total length of the waveguide chip is at a centimeter order; a host material of the coupling waveguide comprises various second order and third order nonlinear optical materials capable of fabricating the waveguide; a nonlinear processes occurring in the coupling region comprises all classical and quantal three-wave and four-wave action processes; the occurring nonlinear processes contain all second-order and third-order nonlinear processes, comprising frequency doubling, difference frequency, sum frequency, parametric amplification and other processes; the generated converted light contains a classical parametric light field and a quantal entangled photon source; and the waveguide chip is manipulated by using integrated thermo-optic and electro-optical effects.

A method and a system method for generating optical multipartite quantum states, comprising generating optical fields by at least two different spontaneous four-wave mixing processes and overlapping the optical fields spontaneously generated from the different spontaneous four-wave mixing processes into a same resonator mode of a third-order nonlinear resonator. The system comprises a multi-colored laser source exiting a nonlinear third-order resonator at different resonance frequencies belonging to different mode families of the resonator.

A method and a system method for generating optical multipartite quantum states, comprising generating optical fields by at least two different spontaneous four-wave mixing processes and overlapping the optical fields spontaneously generated from the different spontaneous four-wave mixing processes into a same resonator mode of a third-order nonlinear resonator. The system comprises a multi-colored laser source exiting a nonlinear third-order resonator at different resonance frequencies belonging to different mode families of the resonator.