10 results about "Terahertz radiation" patented technology

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.

This invention discloses a terahertz water quality detection chip based on phase change materials and its detection method. The detection chip comprises a substrate, interdigitated electrodes, and a phase change film. The interdigitated electrodes are disposed on the substrate, and a microstructure array is arranged between the interdigitated electrodes. The phase change film covers the interdigitated electrodes and the microstructure array. The area covered by the phase change film serves as a droplet sample loading area. The phase change film transforms between an amorphous and crystalline state, thus being suitable for two detection modes. The phase change film is a thin film formed by GST phase change material, which is a compound formed by the combination of Ge, Sb, and Te elements. The above-mentioned detection chip excites the GST phase change material to generate a photoconductive effect through terahertz radiation, and utilizes the high conductivity of pollutants in water to modulate the local terahertz field. It uses the change in photocurrent with particle concentration to form a quantitative detection relationship, thereby significantly improving the sensitivity of water quality detection while reducing the size of the detection equipment.

This invention discloses a terahertz receiver and a focal plane camera device based on a variable capacitor. The receiver includes a connected zigzag inductor and interdigitated capacitors; each finger of the interdigitated capacitor is composed of closely arranged double-cross-shaped repeating units, enabling it to efficiently absorb terahertz waves without the need for an additional absorber. Terahertz radiation changes the dielectric constant of the dielectric, causing changes in capacitance and resonant frequency; detection is achieved by detecting these changes. The focal plane camera device includes an array of the aforementioned receivers. Each receiver is coupled to a zigzag-shaped center feed line via a coupling feed line, and each unit has a different resonant frequency, achieving frequency division multiplexing readout. This invention combines absorption and resonance functions into one, greatly simplifying the structure, achieving high absorption efficiency, possessing dual polarization and intrinsic frequency division multiplexing capabilities, and easily expanding into large arrays. It can be widely applied in fields such as high-sensitivity terahertz passive imaging and spectral analysis.

A terahertz detection method based on a multi-fluorescent organic probe based on molecular skeleton change belongs to the technical field of terahertz wave detection, which adopts a multi-fluorescent organic molecular solution N,N'-diphenyl-dibenzo[a,c] phenazine molecule and derivative and a cyclooctatetraene (COT) ring-fused anthracene molecule and derivative, based on the excited state molecular skeleton change characteristics, through the multi-fluorescent characteristics changing with the terahertz intensity under the terahertz radiation, the terahertz intensity change visualization is realized. This method can detect terahertz waves of different intensities, the field strength measurement range is from kV / cm to MV / cm order of magnitude, which can significantly simplify the terahertz detection process and improve the accuracy of terahertz detection.

The application discloses a spin terahertz emitter with adjustable polarization without an external magnetic field and a manufacturing method thereof. A metal thin film layer heterostructure is deposited on a surface of a glass substrate. A ferromagnetic layer is a FeNi thin film layer, an anti-ferromagnetic layer is an IrMn3 thin film layer, and an interface between the FeNi thin film layer and the IrMn3 thin film layer is an exchange coupling interface subjected to directional magnetic field induction treatment. A surface of the metal thin film layer heterostructure is a periodic stripe array structure. The manufacturing method comprises the following steps: a magnetron sputtering process is used to sequentially deposit a ferromagnetic layer, an anti-ferromagnetic layer and a protective layer; the exchange coupling interface is formed through directional magnetic field induction treatment; and a micro-nano processing process is used for patterning treatment. Beneficial effects are as follows: under the condition of no external magnetic field, reliable spin current generation, spin-charge conversion and terahertz radiation can be realized. The stripe patterning structure realizes linear polarization, elliptical polarization and near-circular polarization output. The 'zero-field emission function' and the 'polarization control function' are integrated in the same thin film device system, and the system complexity is reduced.

The application provides a terahertz emitter film structure based on a Ni / Cr / Ti metal heterostructure and an ion irradiation enhancement method thereof, a substrate material is glass, and a ferromagnetic layer of a Ni film, an intermediate functional layer of a Cr film and a protective layer of a Ti film are sequentially deposited on the surface of the substrate material. The ion irradiation enhancement method comprises the following steps: a ferromagnetic layer of a Ni film, an intermediate functional layer of a Cr film and a protective layer of a Ti film are sequentially deposited on the surface of the substrate material by adopting a magnetron sputtering deposition method, and an intermediate product on which the three metal film layers are deposited is subjected to ion irradiation. The beneficial effects are as follows: the Cr film layer is used to realize ultrafast current transients under femtosecond laser excitation and generate terahertz radiation. The metal film is subjected to ion irradiation treatment, and the terahertz emission intensity is significantly improved.

This invention relates to a terahertz measuring device for measuring the wall thickness of an article, wherein the terahertz measuring device comprises a terahertz transmitter rotatable around or along a rotating ring around a measuring area containing the article during measurement, and a terahertz receiver rotatable around or along the rotating ring around the measuring area, which receives terahertz radiation emitted by the terahertz transmitter onto the article after reflection by the article arranged in the measuring area, and wherein the terahertz measuring device further comprises an analysis and processing mechanism configured to determine the wall thickness of the article from the measurement data of the terahertz receiver. The invention further relates to a method for calibrating such a terahertz measuring device.

A kind of terahertz ice cloud airborne detection system, including antenna subsystem, multiband terahertz receiving subsystem, calibration subsystem and comprehensive processing and control distributor.Antenna subsystem adopts variable speed circumferential scanning mode to carry out detection to target area, obtains terahertz radiation signal, obtains multiple radio frequency signals after distinguishing according to polarization direction and frequency.Multiband terahertz receiving subsystem adopts direct mixing double sideband receiving mode, respectively mixes the radio frequency signal of each road, carries out intermediate frequency filtering, amplification and detection, obtains detection signal.Comprehensive processing and control distributor is powered and controlled for antenna subsystem, multiband terahertz receiving subsystem, calibration subsystem, obtains ice cloud information of observation area according to detection signal inversion.Computer calibration subsystem is calibrated under the control of comprehensive processing and control distributor to detection system.The present application can be adapted to various manned, unmanned aircraft platform.

The present application relates to the technical field of data calibration, and discloses a cloud water icing detection dynamic calibration method and system for an airborne terahertz radiometer, comprising: collecting external environment temperature and humidity data and calibration matching parameters; constructing an influence function of antenna icing on a flight platform on the radiation efficiency of a preset terahertz frequency band; performing icing analysis on the external environment temperature and humidity data to obtain an equivalent icing attenuation factor and correct a target source radiation reference value stored in the airborne terahertz radiometer; analyzing an environment compensation term and a system response term of the external environment temperature and humidity data; synthesizing the icing correction term, the environment compensation term and the system response term with the target source radiation reference value to generate a calibration coefficient; and using the calibration coefficient to compensate and correct real-time received original radiation signals of the terahertz frequency band to obtain a terahertz effective detection signal. The present application can improve the accuracy of cloud water icing detection dynamic calibration.

A method and a device for producing coherent Smith-Purcell electromagnetic radiation. The device includes an electrically conductive diffraction grating laterally defined by two electrically conductive outer side walls; a source for generating an electron beam above the diffraction grating. The electron beam is configured to interact with the diffraction grating so as to produce coherent Smith-Purcell electromagnetic radiation directed upstream of the diffraction grating in a predetermined direction. The device further includes a mirror configured to collect all of the electromagnetic radiation and redirect it parallel to the diffraction grating to an exit downstream of the diffraction grating.