60 results about "Nonlinear refraction" patented technology

The invention relates to a real-time observation single-beam dual-mode parameter adjustable Z scanning device and measurement method. The device mainly comprises a parameter modulation part, a data acquisition part and an observation part, wherein in the parameter modulation part, after passing through an adjustable attenuator and an acoustooptical adjustor, laser is transformed into a laser beam with adjustable power pulse and is focalized onto the surface of a sample by lens; in the data acquisition part, emergent light on the back surface of the sample is divided into two beams by a dispersion prism, one beam of light directly enters a detector thus the nonlinear absorption of material is acquired, and the other beam of light enters the other detector by a small aperture of which the center is coaxial with an optical axis thus the nonlinear refraction of the material is acquired; and in the observation part, a cold light source illumination device is additionally arranged on the light path of the device so that the change of points of action can be observed in real time in experiments. The invention is easy to realize, and can acquire the nonlinear absorption rate and the nonlinear refraction rate of materials in different conditions.

The invention discloses an optical nonlinearity measuring device and a measuring method for nonlinearity thick photonics materials, and belongs to the technical field of nonlinearity photonics materials and nonlinearity photonics measurement. Tophat type laser pulses serve as probe light, a reference standard sample with the suitable thickness is selected according to the thickness of a sample to be measured, the reference standard sample and the sample to be measured are subjected to Z scanning measurement respectively, energy of incident light is adjusted to obtain the same normalization transmittance peak-to-valley values, and a nonlinearity refraction coefficient of the sample to be measured is obtained by data processing. The optical nonlinearity measuring device and the measuring method for nonlinearity thick photonics materials are suitable for nonlinearity photonics materials of which the thicknesses exceed a Rayleigh length.

The invention discloses a method for measuring nonlinear absorption based on geometric optical imaging of a lens. Light output by a laser is divided into monitoring light and detection light; the monitoring light is received by an energy meter probe and is used for monitoring the energy transmitted on a sample to be tested in a real-time mode; the detection light is focused by a focusing lens and then irradiates on the sample to be tested positioned at a focus or the nearby position of the focusing lens; the non-linearity leads the space distribution of the detection light which passes through the sample to change; and the change is recorded by a CCD camera through an imaging lens arranged at the rear position. A theoretical model of a measurement system which works according to the method is simple; and the method has the advantages that the method has easy data processing and quick measurement speed, reduces optical accumulation effect by single pulse measurement, has low sensitivity to the random fluctuation of laser beams, and has accurate measurement results as well as intuitive and clear experimental results, the measurement of non-linear absorption is not affected by non-linear refraction, and so on.

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 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.

The invention discloses a high-sensitivity single pulse single beam measuring method for material optical nonlinearity. A round baffle is arranged in an optical path of a probe light after passing through a sample, and under the function of the single pulse, nonlinear absorption and nonlinear refraction coefficient of the material are determined by measuring a nonlinear transmittance of an open pore and a far field baffle. A measuring system working according to the method provided by the invention is simple in optical path, extremely high in measurement sensitivity and simple in data process, uses the single pulse to measure the sample which is not needed to move, and can simultaneously measure the size of the nonlinear absorption and the nonlinear refraction, so that measurement cost is greatly reduced.

The invention discloses far-infrared high-nonlinear Ge-Te-Se chalcogenide glass. The far-infrared high-nonlinear Ge-Te-Se chalcogenide glass has a formula of Ge20TexSe(80-x) and in the formula, x represents a molar fraction and is in a range of 1-70. The Ge-Te-Se chalcogenide glass does not contain toxic As in the traditional chalcogenide glass and can be prepared through a simple and feasible method. Through use of eco-friendly Te in Ge-Te chalcogenide glass, the Ge-Te chalcogenide glass is optimized through high Te polarizability so that the obtained Ge-Te-Se chalcogenide glass has good permeability, a good glass formation capacity and a superhigh nonlinear refractive index. The far-infrared high-nonlinear Ge-Te-Se chalcogenide glass has a nonlinear refractive index n2 of 10<-17> to 10<-16>m<2>/W and the highest nonlinear refractive index of 2.2602*10<-16>m<2>/W. The far-infrared high-nonlinear Ge-Te-Se chalcogenide glass has a wide application range in a far-infrared area.

The invention discloses Ge-Sn-Se chalcogenide glass and a preparation method thereof on the basis of research of chalcogenide glass regulation and control model and glass structure dynamics. The composition formula of the Ge-Sn-Se chalcogenide glass is GexSnySez, wherein x, y and z respectively represent mole fractions of Ge, Sn and Se; x=1-25, y=1-25, z=50-98. The non-linear property of the Ge-Sn-Se chalcogenide glass is much higher than that of chalcogenide glass free of As (for example, Ge28Sb12Se60 and 85GeS2.15Sb2S3), is higher than or equivalent to that of the As chalcogenide glass, and is 1-2 times of As40Se60; the non-linear refractive index n2 can be up to 4.125*10<-17>m<2>/W; and meanwhile, the Ge-Sn-Se chalcogenide glass has good mid and far infrared permeability and near infrared transmission properties.

The invention relates to an optical limiter with adjustable threshold, comprising a nonlinear refractive material, a diaphragm and a supporting encapsulation device; the nonlinear refractive material and the diaphragm are arranged in the supporting encapsulation device; wherein, the nonlinear refractive material is arranged in front of the diaphragm; the incident laser beam sequentially passes through the nonlinear refractive material and the diaphragm; the diaphragm is provided with a clear aperture with changeable size; and the position of the diaphragm corresponding to the nonlinear refractive material is changed by an adjusting device. Compared with the prior art, the optical limiter utilizes the combination of the thermal lens effect of the nonlinear refractive material and the changeable diaphragm, realizes the optical limiter with adjustable threshold, has simple structure, easy preparation and low cost, has convenient, online and real-time adjustment of the limiting threshold, can be applied to various situations, provides guarantee for the safe use of precise optical devices (including human eyes), and prompting the improvement of the laser protection technique.

The invention relates to an Yb3+ ion fluo phosphate laser glass doped and the manufacture method. The base glass material is P2O5-Al2O3-Nb2O5-MF-RF2, M is Li or Na, R is Mg or Ca, and emitting material is Yb203. The method includes the following steps: mixing raw material, putting into corundum crucible, melting for 1 hour at 1280-1350 degree centigrade, casting and molding, and annealing for 1 hour at 520 degree centigrade. The glass material would have good optical and heat-mechanical feature. Because of adding little Nb205 and fluoride, the glass has high stimulated emission section.

The invention discloses a pump-probe method based on Z-scan. A laser beam is divided into two beams; pumping light is focused on samples to be measured through time delay, so that a non-linear sample generates nonlinear absorption and nonlinear refraction; emergent probe light is divided into two beams through a spectroscope, wherein one beam directly enters a first probe, and the other beam enters a second probe after passing through a diaphragm of small pore diameter with a center coinciding with an optic axis. The pump-probe method is characterized in that phase objects are arranged in the front of a convex lens in a probe light path; the method for measuring the light comprises the following steps: (1) the samples to be measured are put in place, and the energy of the probe light at different times is collected by two probes respectively; (2) a energy curve of the probe light at different delay times is processed, so as to obtain optical nonlinear parameters. A measuring system working according to the method has the advantages that the light path is simple; the data treatment is simple; nonlinear absorption and refraction can be measured simultaneously without the need of separate measurement, and the size and the symbol of the nonlinear refraction can be measured simultaneously; the measuring results are accurate, etc.

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 phase object Z-scan-based pump-probe method, which includes the following steps: an incident laser beam is split into two beams, the beam with high intensity is pump light, the beam with low intensity is probe light, and the pump light is delayed and focused on a non-linear sample to be tested, so that the sample to be tested, which is in the ground state, generates non-linear absorption and non-linear refraction; the sample to be tested is located on the focal plane of a lens in a probe light path, a round diaphragm and a round baffle, the centers of which are superposed with the optical axis, are placed at a far-field position in the probe light path behind the sample to be tested, the emergent probe light is split into two beams by a spectroscope, one of the beams directly enters a first probe, and the other beam enters a second probe after passing through the diaphragm and the baffle. A measuring system which operates according to the method is highly sensitive and can simply process data, non-linear absorption and non-linear refraction can be measured simultaneously rather than separately, and the method has the advantages of accurate measurement results and the like.

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.

A Farady rotating phosphorate glass with low non-linear refractivity and high content of Tb3+ for Farady rotator is on the basis of Tb2O3 and P2O5, and contains Tb2O3 (17-26 mol%), P2O5 (70-80), and small quantity of Sb2O3 and/or As2O3, and further including small-quantity of Al2O3, B2O3, SiO2, R2O and RO. Its advantages are high Verdet constant, low non-linear refractivity, high transparency in visual light or near infrared region, and high stability.

The invention discloses a device for measuring optical non-linearity of a material by single-pulse flat-top light. A round small hole and a round baffle are arranged in a light path of a detection light after passing through a specimen, and the nonlinear transmittance of the open pore as well as the far-field round small hole and the round baffle combination is measured by the measuring method under the action of single-pulse, so as to determine the nonlinear absorption and nonlinear refraction coefficients of the material. When the measuring device works, the measuring system is simple in light path, the measuring sensitivity is extraordinary high, the data processing is simple, single pulse measuring is realized, the specimen is not needed to be moved, nonlinear absorption and nonlinear refraction can be simultaneously measured, and the measuring cost is greatly reduced.

The invention discloses a method for measuring the optical nonlinearity of a material based on monopulse and single beam. A phase object is arranged in a light path in front of a lens of detecting light; and under the action of the monopulse, the nonlinear absorption and nonlinear refraction coefficient of the material are determined by measuring the nonlinear penetration rates of an open pore and a far field pore. A measurement system operates according to the method of the invention has the advantages of simple light path, simple data processing, monopulse measurement, no sample movement, synchronous measurement of the size and symbols of the nonlinear absorption and the nonlinear refraction coefficient, accurate measurement result and great reduction in measurement cost.

The invention discloses a single-pulse measurement method of material non-linearity refraction. A phase object is added in the detection light-path. The material non-linearity refraction is determined by measuring the non-linearity transmittance of a far-field aperture under the action of single-pulse. The single-pulse measurement method has features of simple light-path, simple data processing, single-pulse measurement, no need of moving sampler, simultaneous measurement of size and symbol of the non-linearity refraction, accurate measurement result, greatly reduced measurement cost.

The invention discloses a high-sensitivity material optical nonlinearity measurement pump-probe method. A laser beam is divided into two beams, and a sample is located a certain distance behind the focus of a lens, so that the change of far-field spots is maximized. Pumping light acts on the sample to be detected through time delay, so that the nonlinear sample conducts nonlinear absorption and nonlinear refraction; emergent probe light is divided into two beams by a spectroscope, one beam enters a first probe, and the other passes through a circular baffle of which the center is superposed with the optical axis and then enters a second probe. The method is characterized in that in the path of the probe light, the circular baffle of which the center is superposed with the optical axis is placed on the far field, and the sample is located a certain distance behind the focus of the lens, so that the change of far-field spots is maximized. The following measurement steps are included: firstly, placing the sample to be detected, using the two probes to respectively collect the energies of probe light at different times; secondly, processing probe light energy curves at different delay times to obtain optical nonlinearity parameters. A measurement system working according to the method is extremely high in sensitivity and simple in data processing, realizes simultaneous but not separated measurement of nonlinear absorption and nonlinear refraction, can distinguish nonlinear refraction symbols and is accurate in measurement result.

The invention discloses a nonlinear measuring system capable of changing light intensity. The nonlinear measuring system comprises a programmable laser, a stepping displacement platform and a controlbox, wherein a mirror machine is arranged above the programmable laser; a first aperture diaphragm is arranged on one side of the mirror machine; the stepping displacement platform is placed on one side of a first convex lens; a BS (Beam Splitter) prism is arranged on one side of the stepping displacement platform; a first detector is placed above the mirror machine; and one end of the first detector is connected with the control box by a wire. The nonlinear measuring system provided by the invention solves problems of influence on precision of nonlinear refractive coefficient, lack of measurement under Gaussian beams with different light intensities, lack of intelligence and automation, and lack of research on changes of a nonlinear absorption rate and a nonlinear refractive index of a substance under different light intensities by arranging structures such as the mirror machine, the first detector, the programmable laser, the control box, the first aperture diaphragm, a second aperture diaphragm, the BS prism and the stepping displacement platform.

The invention belongs to the technical field of semiconductor materials, and particularly relates to a preparation method of a graphene and tin oxide hollow sphere composite nanomaterial, wherein themethod comprises the steps: adding deionized water into K2SnO3.3H2O, mixing urea with an ethanol solution, combining a potassium sulfate aqueous solution and a urea solution, and carrying out ultrasonic treatment to form a mixed solution; dispersing graphene oxide into water, adding the mixed solution, uniformly stirring, transferring into a high-pressure stainless steel reaction kettle taking polytetrafluoroethylene as a lining, putting the reaction kettle into a vacuum drying oven, and carrying out reaction; and after the reaction is finished, rapidly putting the high-pressure reaction kettle into ice water to quench, washing the cooled liquid with deionized water and absolute ethyl alcohol respectively, and performing vacuum drying to obtain the G/SnO2 hollow sphere composite nanomaterial. The third-order nonlinear absorption of the G/SnO2 hollow sphere composite nanomaterial synthesized by the method is saturated absorption, the third-order nonlinear refraction is self-focusing, and the G/SnO2 hollow sphere composite nanomaterial is expected to be applied to a mode-locked pulse laser, an optical memory, an optical modulator and the like.