109 results about "Raman laser" patented technology

The invention provides a Raman-meter signal all-day laser radar ratio inversion method and device, and the method comprises the steps: carrying out the denoising of signal data of a Raman laser radar in a preset time period, and carrying out the inversion, and obtaining a first aerosol backscattering coefficient profile; applying a plurality of preset laser radar ratios to the inversion of the meter laser radar signal at the same moment to obtain a plurality of second aerosol backscattering coefficient profiles; taking the first aerosol backscattering coefficient profiles at the same moment as a reference standard, calculating a relative error average value of each second aerosol backscattering coefficient profile, and obtaining an optimal laser radar ratio corresponding to the minimum relative error average value; fitting the optimal laser radar ratio with the mean value of the aerosol depolarization ratio of the meter laser radar below the boundary layer height at the corresponding moment to obtain a relation curve; and substituting the mean value of the aerosol depolarization ratio at the current moment into the relation curve to obtain the laser radar ratio. According to the invention, the inversion precision of the aerosol laser radar ratio is improved.

The invention relates to a terahertz-Raman integrated detection system and method. The detection system comprises a fusion mainframe box and an integrated probe arranged at a sample detection end on the fusion mainframe box, a Raman spectrum module, a terahertz spectrum module, a terahertz optical module and a data analysis module are arranged in the fusion mainframe box; the Raman spectrum module is composed of a Raman laser, a Raman light filter, a Raman grating and a Raman detector which are sequentially connected through a light path; the terahertz spectrum module is composed of a terahertz femtosecond laser, a transmitting photoconductive antenna, a receiving photoconductive antenna and a terahertz detector which are sequentially connected through a light path; the data analysis module is in communication connection with the Raman detector and the terahertz detector and is used for synchronously processing data transmitted by the Raman detector and the terahertz detector. Compared with the prior art, the integrated probe synchronously collects two kinds of spectral data and carries out fusion processing on the two kinds of spectral data through the data analysis module, and the device has the remarkable effects that the device integration degree is high, the detection efficiency and accuracy are greatly improved, and the application range is wide.

The invention relates to the technical field of spectral imaging detection, in particular to a spontaneous-stimulated Raman co-localization single-cell substructure atlas analysis system and a spontaneous-stimulated Raman co-localization single-cell substructure atlas analysis method. The system comprises a femtosecond pulse excitation module used for outputting two beams of broadband femtosecond pulse laser with different frequencies and continuously adjustable optical power; the Stokes light modulation module is used for modulating the Stokes light and carrying out space beam combination on the Stokes light and the pump light; the pump light modulation module is used for modulating pump light; the spontaneous Raman laser continuous adjusting module is used for outputting spontaneous Raman laser; the stimulated Raman exciting light co-positioning module is used for combining the combined laser and the spontaneous Raman laser again, focusing the combined laser and the spontaneous Raman laser on a sample, exciting a stimulated Raman scattering signal, converting the stimulated Raman scattering signal into a digital signal and carrying out data acquisition; and the spectrum detection module is used for collecting the spontaneous Raman scattering light which is reflected and returned along the original light path, and collecting a spectrum signal to form a Raman spectrum. The method has the advantage of improving the accuracy of single-cell heterogeneity structure and cancer cell type discrimination.

Various optical systems for use in a light pulse atomic interferometer (LPAI)-based one-, two-, or three-axis accelerometer or gyroscope are disclosed. As an LPAI accelerometer or gyroscope may employ many different laser beams to implement the LPAI functionality, ways of combining these different laser beams to thereby simplify the optical systems are desired. The cooling laser beam portion of the optical system may be simplified using one or more reflective grating chips. The Raman laser beam optics may be simplified using combiners and separators. For LPAI systems sensing along three axes, various optical switching schemes may be employed, including ones that generate variable data-rates with a primary sensing axis having a higher data-rate than the secondary sensing axes. Further, by combining various laser beams in a time-multiplexed manner, the number of optical fiber tethers to a sensor head may be reduced.

The invention provides a tip Raman-based metal oxide nanoparticle in-situ detection method, which comprises: S1, dispersing metal oxide nanoparticles in a nanoparticle dispersion liquid, focusing laser to the tip of a nanometer tip through an objective lens, capturing a single nanoparticle by using an optical tweezers technology, and attaching the single nanoparticle to the nanometer tip; s2, focusing Raman laser on a nano needle tip-particle interface, generating a local high-temperature field through a photo-thermal near-field coupling effect, triggering a thermal chemical reaction of nano particles, and synchronously collecting a Raman spectrum; and S3, carrying out pretreatment and characteristic peak analysis on the collected Raman signal of the Raman spectrum, and determining the reaction critical temperature and the dynamic process in combination with temperature calibration data. According to the invention, capture and accurate heating of the nanoparticles are realized through photo-thermal coupling of the optical tweezers and the needle tip, and thermal chemical reaction monitoring of the nanoparticles is realized.

The invention provides a holmium and ytterbium co-doped mid-infrared microsphere Raman laser and a preparation method thereof, and relates to the technical field of laser preparation, the holmium and ytterbium co-doped mid-infrared microsphere Raman laser comprises an infrared transmission optical fiber, a pump light source, holmium and ytterbium co-doped tellurate glass microspheres and passive tellurate glass microspheres, pump light emitted by the pump light source is guided to a conical region through the infrared transmission optical fiber, and the holmium and ytterbium co-doped tellurate glass microspheres and the passive tellurate glass microspheres are arranged in the conical region; sequentially carrying out optical coupling with holmium and ytterbium co-doped tellurate glass microspheres and passive tellurate glass microspheres; in the holmium and ytterbium co-doped tellurate glass microspheres, the doping amount of the holmium element is 0.3%, and the doping amount of the ytterbium element is 0.45% according to the mass percentage. Compared with the prior art, through the cascade structure of the holmium-ytterbium co-doped microspheres and the passive microspheres, three-step wavelength conversion of pump light-rare earth ion lasing-Raman frequency shift is realized in a single system for the first time, and the wavelength limitation that a traditional single microsphere depends on a rare earth ion fixed energy level is broken through.

The invention discloses a cold atom interference type low-frequency vibration measurement device and a measurement method, and solves the problems that the existing cold atom interference gravimeter measurement equipment is limited by the performance of a vibration sensor, the compensation precision is insufficient, timing calibration is needed, and the measurement precision is low. And measurement errors generated by gravity and ultralow-frequency vibration cannot be effectively separated from a measurement result of the cold atom interference gravimeter, namely, decoupling of two measurement parameters is realized, and cold atom interference measurement of low-frequency vibration is realized. The measuring device comprises a Raman laser output system, a vacuum cavity, a sensitive axis converter and a vibration detection reflecting mirror, the Raman laser output system outputs two pieces of Raman laser which have the same polarization state and are both circular polarization states; the low-frequency vibration is transmitted to the liquid crystal phase modulator through the vacuum cavity for polarization state conversion, and then is reflected to the liquid crystal phase modulator or the vibration detection reflector through the polarization splitting prism, so that the interference type low-frequency vibration of the cold atoms is measured, and decoupling of the two is realized.

The present invention relates to a method for separating and enriching a chlorine-37 isotope using a laser photochemical reaction and, specifically, to a method for separating and enriching a high-purity chlorine-37 isotope, which is essential for a next-generation molten chloride fast reactor (MCFR) and the like, by selectively photolyzing specific isotopic molecules of iodine monochloride (ICl) using a high-power fiber laser or a solid-state Raman laser and reacting same with a radical scavenger to effectively terminate a chain reaction. Accordingly, by employing, as a light source, a single-frequency fiber laser or a solid-state Raman laser that has higher power efficiency and easier maintenance than conventional dye lasers and is capable of achieving high power of several kW or more through modular expansion, mass production on an industrial scale can be realized and the economic feasibility of the process can be significantly secured.

The invention may be embodied in other forms than those specifically disclosed herein without departing from itMulti-kW-class blue (400-495 nm) fiber-delivered lasers and module configurations. In embodiments, the lasers propagate laser beams having beam parameter products of <5 mm*mrad, which are used in materials processing, welding and pumping a Raman laser. In an embodiment the laser system is an integration of fiber-coupled modules, which are in turn made up of submodules. An embodiment has sub-modules having a plurality of lensed blue semiconductor gain chips with low reflectivity front facets. These are locked in wavelength with a wavelength spread of <1 nm by using volume Bragg gratings in an external cavity configuration. An embodiment has modules having of a plurality of submodules, which are combined through wavelength multiplexing with a bandwidth of <10 nm, followed by polarization beam combining. The output of each module is fiber-coupled into a low NA fiber. In an embodiment a kW-level blue laser system is realized by fiber bundling and combining multiple modules into a single output fiber.

The invention relates to the technical field of in-situ Raman monitoring microwave plasma chemical vapor deposition devices, and particularly discloses diamond growth in-situ Raman test equipment and a Raman test method, the Raman test equipment comprises a growth device and a Raman laser test device; a detection window is arranged on an upper cover of a reaction chamber of the growth device, and a Raman laser testing device with a height adjusting mechanism, an angle adjusting mechanism and a distance measuring adjusting mechanism is arranged on the outer side of the detection window. The three mechanisms cooperate to accurately focus a laser beam on a diamond wafer edge strongest signal area on a deposition table at an optimal incident angle and an optimal working distance; according to the method, in the process of growing the diamond through microwave plasma chemical vapor deposition, Raman spectrums are collected and analyzed in real time, and technological parameters are dynamically fed back and optimized. And finally, high signal-to-noise ratio, in-situ and real-time monitoring and accurate control of the diamond growth process in a high-temperature plasma environment are realized.

The application belongs to the technical field of spectral detection, and specifically discloses a kind of characterization methods of fuel cell membrane electrode interface working condition Raman signal, comprising the following steps: constructing fuel cell suitable for Raman test, preparing membrane electrode, assembling fuel cell, assembling in-situ Raman spectrum detection device, detecting fuel cell membrane electrode Raman signal.The application constructs fuel cell window piece, and makes laser passage by constructing window piece, optimizes flow field plate structure and material, avoids the problem that Raman laser cannot be focused due to too large distance from window piece to membrane electrode and the problem that operation platform is unstable due to too heavy weight of fuel cell, and can detect membrane electrode spectral information;The application can be applied to signal detection in different electrocatalytic reaction processes of membrane electrode cathode and anode, thereby providing guidance for the design of electrocatalyst.

The application discloses a method for measuring a detection tilt angle of a two-component atomic shearing interferometer, constructs a tilt angle set of a swing angle device; the angle of a mirror is turned between the time when atoms are subjected to the action of a pi Raman laser and a second pi / 2 Raman laser; a plurality of groups of odd number and even number are alternately detected; all tilt angles in the tilt angle set are traversed; and the actual included angle of the longitudinal direction of a CCD camera imaging surface relative to the Z-axis direction is calculated by fitting. The application also discloses a measuring device for the detection tilt angle of the two-component atomic shearing interferometer. The application enables the current atomic shearing interferometer to accurately measure the tilt angle of the detection system, thereby solving the problems of noise and system error caused by the non-zero return of the tilt angle of the detection system of the atomic shearing interferometer, and suppressing the drift of the differential measurement of the two-component atomic interferometer caused by the change of the tilt angle.

The invention discloses a Raman beam combination laser amplifier, relates to the technical field of laser, and aims to solve the problem of low conversion efficiency of an existing beam combination laser amplifier. A first bowl-shaped reflecting mirror and a second bowl-shaped reflecting mirror are coaxially arranged at the two ends of a columnar reflecting mirror assembly, the concave surfaces face the columnar reflecting mirror assembly, and a Raman laser crystal is arranged in the columnar reflecting mirror assembly; seed light output by the seed light module enters the Raman laser crystal through the center of the first bowl-shaped reflector; and a plurality of beams of fundamental frequency light output by the plurality of fundamental frequency light modules are obliquely incident to the Raman laser crystal from the side surface of the columnar reflector assembly. Each beam of fundamental frequency light of the Raman beam combination laser amplifier can be reflected for multiple times in the amplifier and interacts with the seed light for multiple times, the conversion efficiency of the single beam of fundamental frequency light is improved, the adjustment difficulty of the fundamental frequency light module is low, and the Raman beam combination laser amplifier is suitable for integrated use.

The application discloses a high-power single-mode linear polarization Raman fiber laser based on a multimode optical fiber, and is characterized in that: a Raman gain medium of the laser is a single-clad circularly symmetric step-index distribution large-core multimode optical fiber; a base mode diameter of the step-index large-core multimode optical fiber is more than 65% of a core diameter; a Bragg fiber grating is inscribed in the core of the multimode optical fiber by using a femtosecond laser direct writing technology; a long axis of the grating region is coincided with a base mode field supported by the multimode optical fiber in a radial direction in space and length; the grating forms selective optical feedback only to the base mode in the cavity; a grating region with a difference between the long axis and the short axis forms selective feedback to one polarization state of the base mode; thus, the multimode optical fiber Raman laser effectively suppresses generation of mode instability at a high power level through active mode cleaning, and finally realizes near-diffraction-limited single-mode, high linear polarization and high-power Raman fiber laser output.

The embodiment of the invention discloses a Raman sampling device, which comprises a Raman laser used for outputting a first parallel light beam; the negative lens unit is used for diverging the first parallel light beam output by the Raman laser; the positive lens unit is used for converging the diverged first parallel light beams and integrating the diverged first parallel light beams into second parallel light beams; and the included angle between the axis of the light guide rod and the second parallel light beam is smaller than or equal to 5 degrees, so that the second parallel light beam is reflected in the light guide rod for more than 5 times. The Raman sampling device disclosed by the invention has the beneficial effects that the Raman sampling device realizes uniform distribution of exciting light of large light spots through the beam expanding and light uniformizing structure; a multi-point optical fiber collection structure is adopted, so that the scattered light collection efficiency is improved, and the detection repeatability and representativeness are ensured; the combination of the annular multiple optical fibers and the diffusion film is adopted at the receiving end, the multi-angle collection capacity of Raman scattering light is improved, the Raman sampling device is suitable for rapid detection of heterogeneous samples, and the problem of poor spectrum reproducibility is solved.

The present invention discloses a wavelength-tunable Raman fiber laser based on gain control, comprising a second feedback component, a second coupling component, a gain component, a first coupling component, an output component, and a first feedback component, which are sequentially connected to form a linear cavity structure, and further comprising a second excitation component and a first excitation component. The light output by the first excitation component and the second excitation component has different central wavelengths. The present invention has a simple structure, wherein two pump lights of different central wavelengths are selected, each of which is power-amplified by an amplifying component and then coupled into a Raman gain fiber, i.e., a gain component. After the two Raman net gain spectra are superimposed on each other, Raman laser light can be emitted at the point of highest gain in the resonant cavity. Compared with traditional tunable Raman fiber lasers, there is no need for costly wavelength-tunable pump sources and tunable filters, and the resonant cavity structure is simple and compact with low loss.

The invention discloses a complete common mode rejection two-component atom interferometer which comprises a vacuum system, detection laser, second Raman laser, third Raman laser and compensation light are arranged above the top of the vacuum system, and a reflector is arranged below the bottom of the vacuum system. The first Raman laser and the fourth Raman laser are reflected by the reflecting mirror, are incident to the vacuum system from the bottom of the vacuum system, and are propagated upwards along the extension direction parallel to the central axis of the vacuum system; by setting Raman laser of a prime specific frequency relation, a light intensity proportional relation and a spatial position relation corresponding to a first component and a second component of a cold atomic group in a vacuum system, the two-component atom interferometer can realize complete suppression of common-mode noise during differential measurement. According to the invention, the technical bottleneck problem that the measurement precision is limited due to the fact that the noise of the internal-state controllable two-component atom interferometer cannot completely suppress the common mode is solved.

The invention relates to a double-path beam-combining Raman laser power time-sharing locking device and method, an acousto-optic modulator is used for dividing an optical signal emitted by a laser into a first optical path and a second optical path, a first power modulator and a first diaphragm are sequentially arranged along the first optical path, a second power modulator and a second diaphragm are sequentially arranged along the second optical path, and the acousto-optic modulator and the second diaphragm are sequentially arranged along the second optical path. The first light path and the second light path are intersected on the light combination prism, and the power detection assembly is arranged on an output light path of the light combination prism; the first diaphragm and the second diaphragm are alternately opened according to a preset time sequence, power monitoring is performed on the first optical path or the second optical path through the power detection assembly, and feedback adjustment of optical power is performed on the first optical path through the first power modulator according to a monitoring result. And according to the monitoring result, feedback adjustment of the optical power is carried out on the second optical path through a second power modulator, so that power locking of the first optical path and the second optical path is realized in a preset error range.

The application provides a solid-liquid system preparation and interface thermal resistance measurement method based on Raman scattering, which comprises the following steps: step 1, preparing a substrate with SERS effect; step 2, transferring two-dimensional nanomaterial on the surface of the SERS substrate prepared in step 1, and the thickness of the two-dimensional nanomaterial is not more than 2 nm; step 3, selecting a solution with SERS effect and heat-sensitive effect and combining the solution with the solid part obtained in step 2; and step 4, performing Raman spectrum measurement on the solid-liquid system prepared in step 3 under variable laser power, obtaining the offset amount of the Raman spectrum characteristic peaks on both sides of the solid-liquid interface with the incident laser power by changing the incident power of the Raman laser, and determining the temperature rise of the solid-liquid interface through the offset amount. The measurement type is non-contact measurement, the integrity of the measured sample can be maintained, and different kinds of solid materials can be used for thermal resistance measurement according to actual measurement requirements.

The invention relates to a real-time vibration compensation device and method for a cold atom gravimeter. The device comprises a Raman laser, a rubidium atomic group, a reflector, an accelerometer, an optical phase-locked loop module, an analog-to-digital converter, a reference clock source, a heteronuclear FPGA, a direct frequency generation module and an upper computer. Two pairs of Raman lasers oppositely act on a rubidium atomic group in the vertical direction, the accelerometer and the reflector are in rigid connection, analog differential signals of the accelerometer enter the analog-digital converter, converted digital signals enter the heteronuclear FPGA for digital calculation, and the reference clock source serves as clock signals of the digital circuit. A signal calculated by the heteronuclear FPGA enters the direct frequency generation module and is output to the optical phase-locked loop to control the phase of the Raman laser, and the heteronuclear FPGA communicates with the upper computer through TCP connection. The vibration real-time compensation device for the cold atom gravimeter is fully digital, and has the advantages of large dynamic range, low noise and high-precision phase synchronization compensation capability.

The application discloses a narrow linewidth tunable Raman laser and an emission method, relates to the field of Raman lasers, and comprises a half-wave plate, a pump source and a focusing lens which are arranged on the two sides of the half-wave plate, a laser resonant cavity is arranged on the other side of the focusing lens, a cavity locking frequency doubler is arranged on the other side of the laser resonant cavity, a shaping lens group is arranged between the laser resonant cavity and the cavity locking frequency doubler, a dichroic mirror is arranged on the other side of the cavity locking frequency doubler, the laser resonant cavity is arranged in a V-shaped cavity structure which is composed of an input mirror, an output mirror and a reflective blazed grating, a diamond crystal is arranged between the input mirror and the output mirror, and the reflective blazed grating is arranged below the diamond crystal. The stability of the laser resonant cavity is improved through the design of the cavity mirror, the wavelength adjustment is accurate to 0.01 nm, and the loss in the transmission process is reduced through the cavity locking frequency doubler of the ring-shaped cavity structure.

The application relates to a Raman laser carrier sideband ratio feedback control system and a control method thereof. The system is used for controlling an IQ modulator of a cold atom interferometer laser system. The control system comprises an F-P resonant cavity, which is used for receiving Raman laser output by the IQ modulator, and simultaneously adjusting the cavity length of the F-P resonant cavity in real time, so as to identify and output transmitted light of different frequency components to a photoelectric detector. The photoelectric detector is used for detecting the transmitted light of different frequency components, so as to output intensity signals of different frequency components to a calculation module. The calculation module is used for collecting the intensity signals of different frequency components, and calculating and outputting the Raman laser carrier sideband ratio to a feedback control module. The feedback control module is used for performing error feedback control on the IQ modulator according to the Raman laser carrier sideband ratio and a preset carrier sideband ratio expected value, so as to realize the locking control of the Raman laser carrier sideband ratio. The application can improve the measurement accuracy and long-term stability of the cold atom interferometer laser system.

The application belongs to the field of Raman laser, and particularly relates to a red-green-blue three primary color large pulse energy Raman laser, which comprises a pumping laser, a plano-convex lens A, a Raman cell and a plano-convex lens B, the pumping laser is a Nd:YAG pulse solid laser, a mixed gas of D2 and inert gas in the Raman cell is pumped by a doubled 532nm pulse laser, three times of focusing are carried out in the Raman cell, and finally first order Stokes red laser, first order anti-Stokes blue Raman laser and green pumping laser are simultaneously output, the pulse energy reaches above 140mJ, 50mJ and 140mJ respectively, and the peak power reaches 10MW level. The application has the advantages of simple structure, fast debugging, low cost and high peak power of output laser, and provides a Raman laser for generating red-green-blue three primary color laser with high cost performance and large pulse energy.

A narrow-linewidth internal cavity Raman laser, belonging to the field of Raman lasers, is disclosed to address the problems existing in current Raman lasers. The invention includes a laser emitting section, an SRS effect cavity, a beam splitter, a pump beam splitter, and a Stokes beam splitter. The laser emitting section emits a first optical signal with a tunable first preset power and a first preset wavelength into the SRS effect cavity. The first optical signal is amplified in the SRS effect cavity to generate a second optical signal, wherein the first and second optical signals are pump lights with different powers and wavelengths. In the SRS effect cavity, the second optical signal is converted into Stokes light using stimulated Raman oscillation, leaving a portion of unconverted pump light. The Stokes light and the unconverted pump light are separated by the beam splitter, causing the Stokes light to oscillate in the seed beam oscillation cavity and the residual pump light from the stimulated Raman effect to oscillate in the pump beam oscillation cavity, thereby outputting a narrow-linewidth laser.

This invention provides a miniaturized high-pulse-energy Raman laser under vortex optical pumping conditions, relating to the field of Raman laser technology, and employing n 2 A square array of vortex phase plates serves as the optical element for generating vortex-pumped lasers. By adjusting parameters such as the topological charge of the array of vortex phase plates and the focal length of the array of short-focal-length lenses, the laser power density in the focal region is reduced. The focal region has n 2 A square array is arranged with ring-shaped light intensity distribution units, ensuring that the laser power density of each unit in the focal region is greater than the Raman laser generation threshold and less than the laser-induced breakdown threshold. Therefore, the total Raman laser energy is n times the Raman laser energy generated by each unit. 2 This technology ultimately enabled the output of high-energy, high-beam-quality Raman lasers, with Raman laser pulse energies reaching hundreds of millijoules or even joules.

The invention belongs to the technical field of Raman spectrum analysis, and particularly relates to an optical flow control Raman sensing chip based on an SERS substrate and a preparation method of the optical flow control Raman sensing chip. Comprising a first PDMS layer, a silicon-based optical waveguide layer and a second PDMS layer, the silicon-based optical waveguide layer is arranged on the top surface of the first PDMS layer, the silicon-based optical waveguide layer is provided with a top surface and two side surfaces, the second PDMS layer is located on the top surface and the side surfaces of the silicon-based optical waveguide layer, the surface, facing the side surface of the silicon-based optical waveguide layer, of the second PDMS layer is provided with a near-concentric cavity, and the near-concentric cavity is communicated with the silicon-based optical waveguide layer. The SERS composite layer is arranged in the near-concentric cavity, a reflecting film is arranged on the arc-shaped inner wall of the near-concentric cavity, a target solution is specifically combined with the SERS composite layer through the microfluidic channel, the SERS composite layer loaded with the target generates Raman laser under excitation of pump light, and the Raman laser outputs enhanced Raman laser under the synergistic effect of the arc-shaped inner wall and the reflecting film. Through the multi-dimensional coupling enhancement effect of the cavity structure, the collection efficiency of Raman signals is remarkably improved.

This invention discloses a two-component atomic interferometer for large momentum transfer based on four-wave dual-diffraction Raman spectroscopy. It includes a vacuum system, within which cold atomic clusters comprise two components. First, second, and third Raman lasers incident on the vacuum system constitute the Raman light of the first component, while first, second, and fourth Raman lasers constitute the Raman light of the second component. Frequency variations in the third and fourth Raman lasers compensate for the Doppler frequency shift caused by the difference in recoil velocity during the large momentum transfer of the two atomic components. This invention utilizes the insensitivity of the two-component atomic interferometer to the third frequency of the Raman laser. By independently adjusting the frequency of the non-shared lasers of the two-component atomic interferometer, it achieves large momentum transfer in the two-component atomic interferometer while ensuring common-mode suppression of phase noise in the two-component atoms, and without limiting the number of recoil photons by the Doppler frequency shift difference, thus improving the accuracy of differential measurements.

The application discloses a preparation method of positively charged and LSPR wavelength controllable aggregated nano silver, which is a one-step method for preparing aggregated nano silver with controllable and adjustable LSPR wavelength in the range of 532 nm to 785 nm by using cetyltrimethylammonium bromide as a special surface coating agent and a connecting agent, adjusting the pH of a solution, and matching three commonly used Raman lasers (532, 633 and 785 nm) so that the electromagnetic field enhancement effect reaches the best state. Meanwhile, the chemical enhancement effect is coordinated, so that the detection sensitivity of the measured molecules is improved. The preparation method is simple in operation, environment-friendly, low in technical requirement and high in operability. The material obtained by the application can keep a long-term stable aggregation state in a solution, so that the material can be directly used as a liquid substrate for surface enhanced Raman and applied to sensitive detection of some pesticide residues and illegal food additives.

This application provides an in-situ testing system, comprising: a light source including a Raman laser emitter, a heated laser emitter, and an X-ray emitter; an emission optical path for directing a first Raman test beam and a first heated test beam to a first position on the front side of the sample, and directing a second Raman test beam and a second heated test beam to a second position on the back side of the sample; the sample being located within a diamond anvil cell; a receiving optical path for directing a first Raman reflected beam, a first heated reflected beam, a second Raman reflected beam, and a second heated reflected beam to a spectrometer; a spectrometer for determining the pressure and temperature parameters of the front and back sides of the sample; and a detection device for receiving diffraction signals and determining the lattice parameters of the sample based on the diffraction signals. This in-situ testing system integrates Raman testing, heated laser testing, and X-ray testing into one unit, enabling the acquisition of pressure, temperature, and lattice parameters on both sides of the same sample location.

This invention relates to the field of laser technology, and particularly to a Raman laser that outputs 9.2μm far-infrared laser light. It includes a laser pump beam splitting module, a first-order Raman laser generation module, a difference-frequency seed light preparation module, a laser beam combining and tuning module, a second-order Raman amplification module, and a laser collimation and separation module arranged sequentially along the optical path. The laser pump beam splitting module is used to achieve beam splitting and control of the 1064nm laser; the first-order Raman laser generation module is used to generate a 1.9μm first-order Raman laser from hydrogen; the difference-frequency seed light preparation module is used for difference-frequency preparation of the 9.2μm Raman seed light; the laser beam combining and tuning module is used for spatiotemporal overlap and beam combining of the pump light and the seed light; the second-order Raman amplification module is used for Raman amplification of the 9.2μm laser; and the laser collimation and separation module is used for collimation and separation of the target laser output. This invention utilizes a difference-frequency method to generate wavelength-matched far-infrared Raman seed light, and performs Raman amplification to ultimately obtain a 9.2μm far-infrared Raman laser with high pulse energy and high peak power.