145 results about "Terahertz radiation" patented technology

The invention relates to a terahertz radar imaging system based on four-inch spinning, which belongs to the technical field of terahertz wave imaging and comprises a femtosecond laser light source, a beam splitter, a laser pumping terahertz transmitting module, a detection laser transmission module and a terahertz detection module which are arranged along the laser incidence direction. An efficient, large-size and ultra-wideband terahertz radiation source and a radar imaging device are fused, high-signal-to-noise-ratio and high-resolution terahertz imaging of a large-size target is achieved, and the system is low in cost, easy to construct, free of complex parabolic mirror combination, firm and reliable in performance and suitable for large-size target imaging. And the requirements of various engineering application scenes on synthetic aperture and nondestructive detection imaging can be practically met.

The invention discloses an extensible silicon-based terahertz radiation array source based on an on-chip micro-convex antenna and a terahertz radiation source. The extensible silicon-based terahertz radiation array source based on the on-chip micro-convex antenna comprises a plurality of array units formed by cross-coupled harmonic oscillators based on the on-chip micro-convex antenna, and the array units are connected to form the extensible silicon-based terahertz radiation array source of an n * n array structure. According to the extensible silicon-based terahertz radiation array source, the on-chip micro-convex antenna radiation structure meets the terahertz frequency and broadband requirements, the extensible silicon-based terahertz radiation array source can be applied to a terahertz radiation source system, and the terahertz radiation source array system which is high in working frequency, high in radiation power and tunable in broadband can be achieved.

A method for analysing a sample comprising a layer having a first interface and a second interface, the method comprising: Irradiating the sample with a pulse of terahertz radiation, said pulse comprising a plurality of frequencies in the range from 0.01 THz to 10 THz; Detecting radiation reflected from the sample to produce a sample waveform; Obtaining a first reflection waveform from the sample waveform, the first reflection waveform corresponding to the reflection from the first interface; Obtaining a second reflection waveform from the sample waveform, the second reflection waveform corresponding to the reflection from the second interface; Comparing the first reflection waveform with the second reflection wave-form to produce an estimate of a thickness and a complex refractive index of the layer; Producing a synthesised signal using the estimate of the thickness and complex refractive index; Varying at least one of the thickness and complex refractive index to reduce an error between the sample waveform and the synthesised signal; and Outputting the thickness of the layer.

The invention provides a terahertz vortex radiation generation device based on transverse phase shaping. The terahertz vortex radiation generation device comprises an injector, a laser electron beam modulation system and a terahertz radiation section which are arranged in sequence, the femtosecond laser system comprises a femtosecond laser device, a first beam splitting piece and a first reflecting mirror which are arranged in sequence and are parallel to the electron beam transmission axis, and the first beam splitting piece divides femtosecond Gaussian laser pulses from the femtosecond laser device into a first path of femtosecond Gaussian laser and a second path of femtosecond Gaussian laser; the first path of femtosecond Gaussian laser and the injector are sequentially arranged along the light path of the first path of femtosecond Gaussian laser, and the first reflector, the pulse broadening and beam splitting system and the laser electron beam modulation system are sequentially arranged along the light path of the second path of femtosecond Gaussian laser. According to the terahertz vortex radiation generating device, the longitudinal frequency of terahertz vortex beat frequency laser can be adjusted through the spiral phase plate, the transverse orbital angular momentum of terahertz vortex beat frequency laser can be changed through the adjustable delayer, the layout is simple, the tunability is high, and the terahertz vortex radiation generating device is flexible.

Systems and methods include a computer-implemented method for analyzing rock samples. Rock and oil electromagnetic baselines are determined for rock samples in at least a section of an electromagnetic spectrum ranging from ultraviolet to long terahertz radiation. An aging process is conducted on each rock sample, initially starting with the rock and oil electromagnetic baselines. The aging process is repeated using spectrometry on the rock sample and measured wettabilities of the rock sample until changes in spectra are less than a predetermined threshold. Aging information including the spectra and wettabilities are stored in a machine learning database. Spectra are obtained from an unknown rock sample. The spectra are mapped to clusters in the machine learning database. Wettability ranges are determined for the unknown rock sample based on a mapping of the spectra of the unknown rock sample to clusters in the machine learning database.

The invention discloses a nanosecond pulse hollow cathode electron beam current evaluation system, which aims at the problem of limited capacity of a current satellite communication channel, researches a nanosecond pulse high-current electron beam for driving a terahertz radiation source, and measures electron beam current and energy density distribution. The device is fixed on a four-axis motion platform through a Faraday cup with a slit hole, and the four-axis platform comprises an x axis, a y axis, a z axis and an R axis. Under the driving of the four-axis platform, the nanosecond time response Faraday cup can rotate around the z axis and sweep the section of the electron beam at a certain rotation angle in the direction perpendicular to the slit, and accordingly parallel projections of the electron beam at different angles are obtained. And current density distribution of a certain section of the electron beam is obtained through a filtering back projection algorithm program of the computer. On the basis, the three-dimensional density distribution of different energy electrons is obtained by changing the axial distance and the electron energy screening voltage, and then the time-space domain distribution of the electron beam energy density is obtained.

Method for determining at least one property of at least one first layer than can be applied to a substrate using terahertz, THz, radiation, comprising: determining at least one property of the substrate, applying the first layer to the substrate, determining the at least one property of the first layer.

The invention discloses a low-temperature blackbody source radiation power calibration method, which comprises the following steps of: establishing a low-temperature test system, and calibrating the radiation power of a low-temperature blackbody source; changing the bath temperature of the superconducting dynamic inductance detector, testing response curves of the superconducting dynamic inductance detector at different bath temperatures, and extracting response amplitudes; calculating the number of quasi-particles under the bath temperature of the corresponding superconductive dynamic inductance detector; fitting the response amplitude and the quasi-particle number to obtain a function of the quasi-particle number of the superconducting dynamic inductance detector with respect to the response amplitude; the bath temperature of the detector is reduced to be lower than 100 mK, the temperature of the low-temperature blackbody source is reduced to be lower than 4 K, the temperature of the low-temperature blackbody source is changed, curves of the superconducting dynamic inductance detector at different blackbody source temperatures are tested, and amplitudes are extracted; calculating to obtain a corresponding quasi-particle number; calculating the radiation power of the low-temperature blackbody source according to the quasi-particle quantity; and calculating the radiation efficiency of the low-temperature blackbody source. The problem that the terahertz radiation power of the blackbody source cannot be calibrated at extremely low temperature can be solved.

The invention discloses a terahertz technology detection and identification system and method, and relates to the technical field of terahertz technology material detection.The system comprises a femtosecond laser amplifier, a strong field terahertz radiation generation assembly, an electro-optical sampling assembly and a computer, and the femtosecond laser amplifier is used for emitting femtosecond laser pulses; the strong-field terahertz radiation generation assembly is used for generating a strong-field terahertz radiation beam and combining the strong-field terahertz radiation beam with the detection laser after the strong-field terahertz radiation beam penetrates through the to-be-detected sample; the electro-optical sampling assembly is used for electro-optical sampling; and the computer judges whether the to-be-detected sample is a natural material or an artificial material. According to the invention, the self-developed strong-field terahertz time-domain spectroscopy technology is used for detection, and compared with a traditional radioactive ray detection method and weak-field terahertz radiation, the strong-field terahertz radiation has the advantages of high power, high penetrability, high signal-to-noise ratio and the like in addition to low photon energy and no damage characteristics; the subtle differences of different materials of the same material can be identified more accurately, and the accuracy of detecting and identifying the types of the materials is effectively improved.

The invention discloses a polarization-adjustable antiferromagnetic terahertz source based on a MnPt heterojunction. The polarization-adjustable antiferromagnetic terahertz source comprises a MnPt antiferromagnetic thin film layer, a light metal layer and an anti-oxidation layer, according to the invention, the femtosecond laser is used for exciting the femtosecond laser to generate the terahertz wave, the polarization direction of the generated terahertz wave is changed along with the change of the polarization direction of the femtosecond laser, that is, the polarization direction of the laser is changed by 1 degree, the polarization direction of the terahertz is changed by 2 degrees, the change of the azimuth angle of a sample is not needed, and the width of the generated terahertz spectrum exceeds 5 THz. No extra heavy metal layer needs to be added, the size is miniature, and the thickness is smaller than 40 nm. By adjusting polarization and phase difference of femtosecond laser, adjustability of a linear polarization state, an elliptical polarization state or a circular polarization state can be achieved, the structure is simple, a needed light path is simple, assistance of an external magnetic field or current is not needed, micromachining is not needed, the ultra-high external magnetic field interference resistance is achieved, the cost is reduced, and the application range is wide. And integration of the terahertz source is also facilitated.

The invention relates to an arrangement (1) for non-invasively characterising cerebrospinal fluid and other bodily fluids, • comprising a sensor head (7) for emitting terahertz radiation (T) and receiving its reflections (R), which sensor head, during use, is applied to the patient (3) in such a way that the terahertz radiation (T) radiates into the bodily fluid, • comprising an electronic evaluation circuit for calculating measurement data from the emitted and received radiation (T, R), wherein this circuit automatically determines the extinction of different wavelengths and, from this, calculates the concentration of different substances in the bodily fluid, • and comprising a display (8) for optically representing the data calculated by the evaluation circuit as results.

The invention discloses a terahertz radiation source driven by an electron beam in a magnetized coaxial gun plasma, and belongs to the field of terahertz wave technology. The terahertz radiation source comprises a vacuum diode assembly and a magnetized coaxial plasma gun assembly. The vacuum diode assembly comprises at least a diode cathode and a diode anode, and the magnetized coaxial plasma gun assembly comprises at least a solenoid coil, a fast gas injection valve, a coaxial gun inner electrode and a coaxial gun outer electrode. The invention generates a high-current relativistic electron beam through a vacuum diode assembly, and generates a magnetized plasma through a magnetized coaxial plasma gun assembly, forming a low-density electron beam injected into a high-density plasma, and exciting electromagnetic radiation with a frequency in the range of 0.1THz-10THz, covering the entire terahertz band.

The invention discloses a terahertz detection unit based on a dielectric couple two-level system and an array detector. The array detector comprises an array composed of resonance detection units. The resonance detection unit comprises a broken line inductor, an interdigital capacitor and a coupling feeder line which are connected, and a dielectric layer and an absorber are stacked on the interdigital capacitor. Wherein the absorber is located above the dielectric layer, so that the dielectric layer isolates the interdigital capacitor from the absorber; and the broken line inductor, the interdigital capacitor, the coupled feeder line and line bodies connected among the components are all made of superconducting materials. The absorber is a grid body made of a non-superconducting metal material. After the absorber is used for receiving terahertz radiation, energy is transmitted to the dielectric medium, a dipole two-energy-level system in the dielectric medium is changed, the dielectric constant of the dielectric medium is changed, then the resonant frequency of the resonance detection unit is changed, and terahertz wave detection and imaging are achieved by analyzing the change of the resonant frequency of the resonance detection unit.

The invention provides a terahertz generation and radiation device based on a double-ellipse conical groove antenna, which mainly comprises a terahertz generation part and a terahertz radiation part, and different device units in the terahertz generation part are used for generating terahertz based on two received light waves with different phase differences. Converting two beams of light waves with a specific phase difference into terahertz waves by using a light wave difference frequency effect, wherein the terahertz waves inherit the phase difference of the light waves; and the terahertz radiation part is used for radiating the terahertz waves to a free space so as to realize beam steering of the terahertz waves in a far field. Furthermore, the invention also discloses a terahertz phased array system. According to the invention, wide-angle and grating lobe-free scanning of terahertz wave beams can be realized, and a large-scale array can be realized.

The invention relates to a terahertz spectrum detection system and method, and the system comprises a laser system, a laser frequency locking system, an optical fiber coupling transmission system, a light spot shaping system, a terahertz fluorescence conversion system, a terahertz radiation source, and a fluorescence spectrum detection system. The laser frequency locking system is used for carrying out frequency locking on the two laser beams, the optical fiber coupling transmission system is used for transmitting the two laser beams after frequency locking to the light spot shaping system so as to shape the two laser beams after frequency locking, and the two laser beams after shaping excite cesium atoms in the terahertz fluorescence conversion system to a first Rydberg state; the terahertz radiation source is used for emitting terahertz light, the terahertz light excites the cesium atoms in the first Rydberg state to the second Rydberg state, and the cesium atoms in the second Rydberg state are de-excited to generate a fluorescence signal; the fluorescence spectrum detection system is used for collecting and detecting fluorescence signals.

The invention relates to a terahertz directional radiation source and an implementation method thereof, the terahertz directional radiation source is formed by arranging four plasma filaments in a pairwise orthogonal mode, and each plasma filament is formed by ionizing air after laser pulses with the same power are focused. The terahertz source is dominated by directional terahertz radiation perpendicular to the plane where the four light filaments are located, the radiation intensity is increased along with the increase of the length of the light filaments, and meanwhile the directional performance of the terahertz radiation is kept all the time. The terahertz radiation generation method solves the problems of large divergence angle, poor directionality, difficulty in splitting in common-beam transmission with laser filaments and the like of common single-filament radiation terahertz waves, and is expected to promote the development of technologies such as terahertz imaging and the like.

The application provides a high-power multicolor terahertz radiation generation device based on beat laser accumulation, which comprises an injector, an electron beam modulation system and a radiation system arranged in sequence; and a femtosecond laser system comprising a femtosecond laser, a first light splitting plate and a first mirror arranged in sequence and parallel to the electron beam transmission axis, the first light splitting plate splits the femtosecond Gaussian laser pulses from the femtosecond laser into first and second path femtosecond Gaussian lasers, the first light splitting plate, a pulse broadening system and the injector are arranged in sequence, and the first mirror, a laser accumulation system and the electron beam modulation system are arranged in sequence; the laser accumulation system generates beat accumulation laser with multiple terahertz cycles after receiving the second path femtosecond Gaussian laser. The device of the application can realize the center frequency of the multicolor terahertz radiation being adjustable, the number of the multicolor being variable, the frequency and time interval being controllable, the layout being simple, the tunability being strong and the flexibility being relatively high.

The invention relates to the technical field of terahertz wave generation and transmission, in particular to a rectangular waveguide output type photoconductive mixer based on effective dielectric silicon waveguide coupling. The photoconductive mixer comprises a photoconductive substrate used for exciting carriers through a photoconductive effect; the metal planar antenna is arranged on the first surface of the photoconductive substrate and is used for converting carrier current into a terahertz radiation signal; the effective medium silicon waveguides are arranged on the second surface and the two side faces of the photoconductive substrate in a coupling mode, and the second surface is opposite to the first surface; the rectangular waveguide is used for receiving and outputting a terahertz signal; the effective medium silicon waveguide comprises a waveguide core and air hole arrays distributed on the two sides of the waveguide core, and the air hole arrays are configured to enable the effective medium silicon waveguide to form a refractive index gradient so as to constrain transmission of signals in the waveguide core. By adopting the method, rectangular waveguide output can be efficiently realized, and the method has the characteristic of high structural integration degree.

Various aspects relate to a sorting container, a sorting system, and a sorting container arrangement, wherein the sorting container comprises: a container; an inlet opening for inputting waste; an outlet opening for dispensing unsorted waste from the container; a conveying device configured to move waste from the inlet opening to the outlet opening; robotic arms; a sorting outlet associated with a waste type, wherein the robotic arm is configured to transfer an item for dispensing sorted waste from the container from the conveying device to the sorting outlet; a source; and a camera configured to detect terahertz radiation emitted by the source and passed through irradiated waste.

This invention discloses a terahertz radiation device and method based on a dual-layer metasurface, belonging to the field of terahertz radiation technology. The terahertz radiation device based on a dual-layer metasurface includes a first metasurface structure layer and a second metasurface structure layer arranged from top to bottom. The phase modulation array of the first metasurface structure layer is composed of multiple first structural units with different geometric parameters and divided into multiple regions. The center rotation angle of the first structural units in each region is different to form a gradient phase distribution. The excitation array of the second metasurface structure layer is formed by multiple second structural units with identical geometric parameters arranged uniformly. Through the vertical layout and coherent superposition between the two structures, the terahertz radiation intensity is enhanced. Simultaneously, through the gradient phase design of the first metasurface structure, a terahertz vortex beam carrying orbital angular momentum is output, effectively solving the problems of weak radiation intensity and poor vortex effect in traditional single-layer structures.

The invention provides a compact integrated broadband test system, which comprises a TFLN integrated chip module, an optical fiber pumping and modulation module, a terahertz radiation and receiving module and a data acquisition and analysis module, and is characterized in that all the modules are integrated to adapt to 200GHz-3.5 THz terahertz radio communication and radar test requirements; the TFLN integrated chip module comprises a TFLN integrated chip, and a thin film lithium niobate TFLN with the x cutting thickness of 500-700 nm is bonded to a SiO2 / 500 [mu] m high-resistance silicon substrate with the thickness of 4700 nm; the optical fiber pumping and modulation module comprises a mode-locked laser, a dispersion compensation unit, a Mach-Zehnder modulator (MZM) and an erbium-doped optical fiber amplifier (EDFA); the terahertz radiation and receiving module comprises a transmitting link, a receiving link and an optical detection branch; the data acquisition and analysis module comprises a balanced photoelectric detector PD, a data acquisition card and analysis software, the terahertz radio communication and radar test requirements can be subjected to data linkage analysis, the test process is simple, and time is saved.

The invention relates to a portable terahertz security inspection device capable of automatic detection and a working method, and the device is characterized in that a mechanical auxiliary unit is used for driving an object to be detected to move, so that a terahertz wave source emits terahertz radiation, and the radiation penetrates through a sample to be detected, is received by a terahertz linear detector, and is converted into image information; and the automatic detection platform is used for receiving image information, carrying out preliminary integration and enhancement on the input image through an image preprocessing module, judging possible dangerous goods types through a deep convolutional neural network, calibrating each target frame and sending out an early warning. And core technologies such as a terahertz imaging technology and a deep learning algorithm are fused. Compared with the prior art, the system has the advantages of convenient carrying, comprehensive functions, automatic detection and the like, and is convenient to carry, install and use. The system can efficiently adapt to temporary security check of public activities, greatly improve security check quality, effectively prevent security risks, and meet urgent needs in the field of public security and protection.

The invention relates to the technical field of optics, and discloses a broadband circular polarization terahertz source and application thereof, and the broadband circular polarization terahertz source comprises a free electron beam moving along a predetermined direction and a stacked bianisotropic metasurface located above the free electron beam; wherein the stacked bianisotropic metasurface comprises at least two layers of metal gratings which form a stacked structure; the at least one dielectric plate is used for separating the metal grating; wherein the number of layers of the dielectric plate is one less than that of the metal grating; and the metal grating and the dielectric plate form a periodic structure together, and are used for coupling evanescent wave energy of the free electron beam into multiple resonant modes so as to excite broadband circular polarization terahertz radiation. According to the technical scheme provided by the invention, the tunable and compact terahertz source with high power output can be realized.

The invention discloses a Terahertz effective radiation power high-accuracy measurement technology based on a twinborn compensation model, and belongs to the technical field of Terahertz power measurement. The Terahertz effective radiation power comprises the following steps: constructing a twinborn compensation model of which other conditions are the same as those of a Terahertz measurement device except that a Terahertz signal is not received, and realizing measurement of thermal radiation noise power such as environment thermal radiation and circuit thermal radiation on time domain distribution; when a terahertz radiation source works, a terahertz power measuring device is used for measuring an overall detection signal containing terahertz effective power signals and thermal radiation noise complex coupling; and through differential processing of the total detection signal and the thermal radiation noise, complex decoupling of the terahertz effective power signal and the thermal radiation noise is realized, so that the terahertz effective radiation power is accurately obtained. Furthermore, corresponding twin compensation models are configured according to different terahertz radiation power measuring devices, so that high-accuracy measurement of the terahertz radiation power by different measuring devices can be realized.

A method for determining a refractive index in a surface region of an object from a production system which has not cooled to an ambient temperature includes emitting terahertz radiation from a transmitter at an angle of incidence to the surface region of the object. The terahertz radiation is reflected from the surface region of the object and received by a receiver. The refractive index of the surface region of the object from a ratio of the emitted and reflected terahertz radiation is determined using an evaluator in communication with the transmitter and the receiver. The influence of surface properties of the object on a portion of the reflected terahertz radiation is taken into account when determining the refractive index.

The present application relates to a kind of underwater acoustic field detection method and system based on terahertz vortex beam interference and topological charge regulation, belong to precision measurement technical field.The terahertz radiation source emits terahertz beam, after collimating by convex lens, it is incident to terahertz vortex beam generator, and incident beam is modulated as vortex beam of specific topological charge;Beam splitter divides vortex beam into reference wave and test wave;Test wave is reflected back by reflector after being, and carries the displacement information of water surface;Test wave carrying water surface displacement information and reference wave interfere at beam splitter;Interference signal is captured by terahertz probe, and according to interference signal, the amplitude, frequency information of water surface displacement is obtained, so as to obtain underwater acoustic field information.The present application is based on the design technology of vortex beam generation and topological charge modulation device of super surface, further improves the integration and detection precision of terahertz water surface displacement detection system, so as to obtain underwater acoustic field information.

The subject matter of the invention is a sensor pixel (1) for an imaging device (2) for examining a sample (3), comprising: an emitter (4), the emitter (4) being designed to emit electromagnetic radiation in a frequency band of a range comprising high frequencies and terahertz frequencies; a resonator (6) which is connected to the emitter (4) for transmission of the emitted radiation, such that the radiation can be coupled into the resonator (6), the resonator (6) being designed to form, using the coupled-in radiation, a radiation field in an examination region (8), the examination region (8) being a volume for receiving the sample (3); and a pump unit (10) which is connected to the resonator (6) and to the emitter (4) for transmission of the radiation, the pump unit (10) being designed to pump a bound state of the radiation field in the examination region (8) by means of the emitter (4). In this way, improved imaging with high-frequency radiation and terahertz radiation is provided.

The application discloses a scalable silicon-based terahertz radiation array source based on a micro-protrusion antenna and a terahertz radiation source. The scalable silicon-based terahertz radiation array source based on a micro-protrusion antenna comprises a plurality of array units composed of cross-coupled harmonic oscillators based on a micro-protrusion antenna, and the plurality of array units are connected to form an n*n array structure of the scalable silicon-based terahertz radiation array source. The scalable silicon-based terahertz radiation array source has a micro-protrusion antenna radiation structure, meets the terahertz frequency and wideband requirements, can be applied to a terahertz radiation source system, and can realize a high working frequency, a high radiation power and a wideband tunable terahertz radiation source array system.

The invention discloses a polar region cloud layer detection method and device based on day and night adaptive multi-mode fusion. The method comprises the following steps: determining a polar region time period mode according to a solar altitude and environment illumination intensity of a polar region observation point; in the polar day mode, collecting a multi-angle polarization thermal image sequence and a visible light image, generating a cloud probability distribution map, and generating a polar day optical thickness map in combination with a physically guided thickness inversion model; in an extreme night mode, quantum radar echoes and terahertz radiation spectrums are collected, a cloud layer vertical distribution probability graph is generated, and an extreme night three-dimensional cloud mask is generated in combination with radar distance-Doppler constraint; and generating a polar region cloud layer full-time detection result based on the polar day optical thickness map and the polar night three-dimensional cloud mask. According to the invention, high-precision and all-weather detection of the polar region cloud is realized by introducing sensing technologies such as quantum radar and terahertz radiation spectrum and combining deep learning and quantum information processing methods.

The invention discloses a method for preparing a bio-organic fertilizer through straw dry fermentation and co-producing biogas, and relates to the technical field of straw treatment. The method comprises the following steps: treating straws by laser etching, plasma and ionic liquid, pretreating by combining microwave and terahertz radiation, screening and modifying strains, preparing a microbial agent by using a composite culture medium, a micro-fluidic reactor and a photobioreactor, adding nano mineral substances and a composite binder when raw materials are blended, fermenting by adopting a bionic fermentation tank, and intelligently controlling temperature and ventilating; the biogas is purified and detected by an advanced technology, and the organic fertilizer is prepared by a special process. The straw is efficiently treated, the fermentation efficiency is improved, the biogas yield is greatly increased, and the high-quality bio-organic fertilizer is produced; the advantages of environmental protection, energy production and soil improvement are integrated, straw resource utilization is achieved, and multiple economic, social and environmental benefits are brought.