69results about "Solid masers" patented technology

The present application relates to a kind of Cherenkov oscillator using composite fine adjustment magnetic field, the present application includes oscillator cavity and the composite fine adjustment magnetic field being arranged outside oscillator cavity, composite fine adjustment magnetic field includes positive solenoid external magnetic field and fine adjustment magnetic field system, fine adjustment magnetic field system is located between positive solenoid external magnetic field and oscillator cavity, fine adjustment magnetic field system includes first positive solenoid fine adjustment magnetic field, second positive solenoid fine adjustment magnetic field and negative solenoid fine adjustment magnetic field, oscillator cavity includes extraction cavity, extraction cavity is arranged with negative solenoid fine adjustment magnetic field outside, negative solenoid fine adjustment magnetic field is arranged with first positive solenoid fine adjustment magnetic field and second positive solenoid fine adjustment magnetic field outside respectively, the present application uses composite hetero solenoid magnetic field combination magnetic field model in magnetic field design and optimally designs, changes magnetic force line configuration, in turn changes electron beam running track.This kind of design guarantees the distance between electron beam and outer cavity, while using local magnetic field to change electron beam configuration method reduces the distance between electron beam and extraction cavity, improves microwave extraction efficiency.

The invention discloses a generating device of a surface electromagnetic wave radiation source, which can be applied to the technical field of electromagnetic waves. The plasma excitation unit is used for generating plasma, and the plasma acceleration unit comprises an electron acceleration power supply, a cathode end face, a slow wave circuit, a plurality of insulation spacers, a plurality of acceleration poles and an output end face. An electron beam channel is formed in the middle area of the upper surface of the slow wave circuit and the middle area of the lower surface of the cathode end face, the insulation spacers, the acceleration poles and the output end face, and meanwhile the insulation spacers and the acceleration poles are arranged between the cathode end face and the output end face at intervals. The speed of the plasma in the electron beam channel output by the plasma excitation unit is adjusted through the plasma acceleration unit, so that the electromagnetic wave radiation source under the target frequency, the target bandwidth or the target power can be output, and the electromagnetic wave radiation source with high frequency, wider bandwidth and high power can be obtained.

This invention discloses a low-phase-noise arbitrary waveform generation system based on an injection-locked optoelectronic oscillator. It utilizes a dual-polarization Mach-Zehnder modulator to simultaneously realize the injection-locked optoelectronic oscillator and optical domain frequency quadruple, enabling simultaneous microwave signal generation and signal frequency multiplication. The frequency bandwidth of the generated signal is not limited by the injected signal, thus realizing the generation of ultra-wideband signals.

A principle which enables the generation of macroscopic Fock and sub-Poissonian states is disclosed. Generic components of the system include: an electromagnetic structure (possessing one or more electromagnetic resonances), a nonlinear electromagnetic element (such as a nonlinear crystal near or inside the structure), and a source of light. In one embodiment, stimulated gain is used to create large numbers of photons in a cavity, but with very low photon number noise (uncertainty) in the cavity, and thus acts as a Fock laser. This Fock laser is capable of producing these states due to a very sharp intensity-dependent gain (or loss) that selects a particular photon number. The disclosed system and method are robust against both atomic and optical decoherence. Various examples of the new Fock laser design are also described.

This application relates to the field of terahertz emission, specifically providing a low-frequency terahertz emitting device and its fabrication and usage methods. The device includes an excitation material, which is a heterojunction formed by a perovskite layer and a high-resistivity silicon layer. It also includes a first metal layer disposed outside the perovskite layer and a second metal layer disposed outside the high-resistivity silicon layer. During fabrication, a perovskite solution is first spin-coated onto the high-resistivity silicon to form a perovskite layer, and finally, the metal layers are deposited by vapor deposition. During use, a femtosecond laser is incident from one side of the perovskite layer, and a voltage is applied between the first and second metal layers. The applied electric field of this application enhances the interfacial band bending and widens the depletion layer, while simultaneously forming a stable potential gradient in the thickness direction. This makes the transient current change smoother, increases the time constant, and reduces the rate of change of the transient current over time, thereby increasing the proportion of the low-frequency terahertz component and achieving enhanced low-frequency radiation.

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.

To provide a high-output high-frequency generator having a simple configuration.SOLUTION: A high frequency generator (10) of the present invention includes a photoelectric conversion layer (11) that generates electrons by photoelectric conversion, an electron transit layer (101) that allows electrons to transit in the photoelectric conversion layer, an anode layer (12) that is disposed in contact with the electron transit layer and is made of a semiconductor, an anode electrode layer (13) that is disposed in contact with the anode layer and is made of a metal, and an antenna (14) that radiates terahertz waves based on an alternating current generated by the transit of electrons.SELECTED DRAWING: Figure 1

The present application relates to a kind of terahertz emitter and its amplitude regulation method, belong to terahertz regulation field, the terahertz emitter includes from bottom to top sequentially stacked substrate, ferromagnetic layer, non-ferromagnetic layer and antiferromagnetic layer, or including from bottom to top sequentially stacked substrate, antiferromagnetic layer, non-ferromagnetic layer and ferromagnetic layer, can be changed by the direction of applied magnetic field, applied current or applied electric field to the amplitude regulation of above-mentioned terahertz emitter, to change the direction of applied magnetic field, applied current or applied electric field to the amplitude regulation of above-mentioned terahertz emitter, so that the present application designs a kind of terahertz emitter of new structure, and corresponding amplitude regulation method is designed for the terahertz emitter, can realize the efficient regulation of terahertz amplitude.

The invention belongs to the technical field of microwave photons, and provides a double-ring photoelectric oscillator and a stabilizing method thereof. The oscillator is provided with a long ring and a short ring and comprises a stabilizing device; the stabilizing device comprises a first piezoelectric ceramic optical fiber stretcher, a motor space light delay line and a second piezoelectric ceramic optical fiber stretcher; generating two optical probe signals; the first optical probe signal is converted into a first electric probe signal through the long ring; a second optical probe signal is converted into a second electric probe signal through the short ring; an electric probe signal is output after being subjected to detection, coupling and power division; the two frequency mixers respectively carry out homodyne frequency mixing on the electric probe signal and the phase-shifted and non-phase-shifted radio frequency signals to generate a zero-frequency error signal; the two phase-locked loops generate compensation control signals according to the error signals; the control signal adjusts an optical fiber delay line; the stability of the two loops is ensured, the problem of combined signal frequency drift caused by neglecting short-loop delay change is solved, the coherence requirement on optical signals is avoided by electric domain combination, and smooth tuning of the output radio frequency signal frequency is realized.

The application discloses a kind of methods for realizing cylindrical grating coherent Smith-Purcell radiation enhancement, Smith-Purcell radiation is a kind of incoherent spontaneous radiation, the power of radiation is very low, not easy to detect and application, to realize high intensity Smith-Purcell radiation, the application proposes based on quasi-continuous domain bound state enhancement method.First, the electron bunch string is generated using the electron gun;Then, make the electron bunch string pass through the surface of cylindrical metal grating, the repetition frequency of electron bunch string is used as the resonance frequency of quasi-continuous domain bound state, to realize the enhancement of coherent Smith-Purcell super-radiation, and finally the electron enters the collecting electrode.The cylindrical grating coherent Smith-Purcell radiation enhancement method proposed in the application is simple to operate, and has obvious effect, easy integration, low cost and other characteristics.

The invention provides a photoelectric oscillator capable of being used for generating tunable phase coding microwave pulses. The photoelectric oscillator is composed of a tunable laser, a polarization controller, a phase modulator, a dual-drive Mach-Zehnder modulator, an optical circulator, a phase shift fiber bragg grating, a single-mode fiber, a photoelectric detector, an electric amplifier, a microwave source and an arbitrary waveform generator. The invention develops the active mode-locked photoelectric oscillator for generating the phase-coded microwave pulse signal, which is simple in structure and good in tunability. On the basis of an active mode-locked optoelectronic oscillator, a phase modulator is driven by a phase coding signal, so that the duration of each voltage polar code is kept consistent with the loop delay of the optoelectronic oscillator, and a phase-coded coherent microwave pulse sequence is generated. The signal has the advantage of large time bandwidth product, can give consideration to the detection distance and distance resolution of the radar, and has the characteristics of interference resistance, low interception and the like.

An optoelectronic oscillator (100) and a signal processing method, which relate to the technical field of optoelectronics. In the optoelectronic oscillator (100), an electro-optical modulator (110), an optoelectronic detector (120), a first filter (130) and a power divider (140) form an optoelectronic oscillation loop. Compared with a conventional single-passband filter, the first filter (130) in the optoelectronic oscillation loop has an additional low-frequency passband, and thus can excite a pulse train of the low-frequency passband and a pulse train of a bandpass band in the optoelectronic oscillation loop. Since the oscillation of a pulse signal can automatically narrow a pulse train to form an ultrashort pulse train, when the pulse train excited by the bandpass band has undergone pulse narrowing by means of an oscillation mechanism in the optoelectronic oscillation loop, the pulse train excited by the low-frequency passband may further undergo pulse narrowing, such that the optoelectronic oscillator (100) can generate a microwave pulse train which is shorter than that of a conventional optoelectronic oscillator, that is, an ultrashort microwave pulse train.

This invention discloses a self-focusing vortex spin terahertz transmitter and its application, comprising a glass substrate, a spin terahertz thin film, and a magnet pair. The spin terahertz thin film is composed of a ferromagnetic material layer, a heavy metal non-magnetic material layer A, and a heavy metal non-magnetic material layer B. The ferromagnetic material layer is disposed on the upper surface of the glass substrate, and the heavy metal non-magnetic material layers A and B are arranged in a spiral alternating pattern on the outer surface of the ferromagnetic material layer. This invention has a simple structure. By fabricating two specially arranged heavy metal non-magnetic material layers with equal and opposite spin Hall angles on the ferromagnetic material, a spiral spin terahertz Fresnel zone plate is constructed, enabling the generated vortex spin terahertz waves to have a focusing function, thereby improving the integration of the vortex spin terahertz transmitter.

The invention belongs to the technical field of microwave photons, and provides a double-ring photoelectric oscillator with a stabilizing device and a stabilizing method thereof, the double-ring photoelectric oscillator is provided with a long ring, a short ring and a stabilizing device; the stabilizing device comprises a first piezoelectric ceramic optical fiber stretcher and a motor space light delay line; the radio frequency signal source generates a first optical probe signal and a second optical probe signal through modulation; the first optical probe signal is converted into a first electric probe signal after passing through the long ring; a second optical probe signal is converted into a second electric probe signal after passing through the short ring; the first frequency mixer and the second frequency mixer are used for performing homodyne frequency mixing on the electric probe signal and the radio frequency signal to generate a zero frequency error signal; and the two phase-locked loops generate compensation control signals according to the zero-frequency error signals. According to the invention, by outputting the control signal and adjusting the optical fiber delay line, the stability of two loops is ensured, the problem of combined signal frequency drift caused by neglecting short-loop delay change is solved, and the coherence requirement on two paths of optical signals is avoided by electric field combination.

The invention provides a self-starting Fourier domain mode-locked optoelectronic oscillator and a method. The oscillator comprises a sweep-frequency light source used for generating sweep-frequency light with the wavelength changing along with time; the photoelectric oscillation loop comprises a phase modulator, a long optical fiber, a notch filter, an optical detector and an electric amplifier, and the output end of the optical detector is connected with the input end of the phase modulator through the electric amplifier to form a closed loop; the sweep frequency light generates a carrier wave and two sidebands through phase modulation, a notch filter filters one sideband, and residual optical signals are converted into microwave signals through an optical detector after being delayed in a long optical fiber and are fed back to a phase modulator through electric amplification; the microwave power detector monitors loop output power in real time; the control unit adjusts the sweep frequency period of the sweep frequency light source according to the monitoring result, searches and locks a target period enabling the microwave signal power to be maximum, and achieves the self-starting of Fourier domain mode locking.

To provide a high-output high-frequency generator having a simple configuration.SOLUTION: The high frequency generator (10) is provided with a voltage generation part (12) for generating a voltage by the irradiation of feed light, a photodiode (11) for generating electrons by the photoelectric conversion of signal light and converting the electrons into a current by the voltage, and an antenna (13) for radiating radio waves on the basis of the current. The high frequency generation device may include a vacuum package (14), and the voltage generation unit, the photodiode, and the antenna may be provided in the vacuum package.SELECTED DRAWING: Figure 1

The invention relates to the technical field of terahertz generators, in particular to a terahertz wave generator of a carbon nanotube-graphene heterojunction cold cathode, which comprises a contact part, a displacement device is slidably mounted at the side end of the contact part, and a heat dissipation fan is fixedly mounted at the top end of the contact part. The displacement device comprises a terahertz wave generator, connecting rods and a matching plate, the connecting rods are symmetrically and fixedly installed at the top end of the terahertz wave generator, the terahertz wave generator is fixedly installed at the side end of the matching plate, and the contact component comprises a butt joint device, a cleaning device, a shunting device, a positioning device and a supporting substrate. The positioning device is fixedly installed at the top of the side end of the supporting base plate, the flow dividing device is fixedly installed at the top end of the positioning device, and the butt joint devices are slidably installed on the two sides of the positioning device. Through the arrangement of the displacement device and the contact device, the purpose of integrating rapid installation and rapid cooling of the terahertz wave generator is achieved.

The application discloses a spin terahertz emitter and a chiral regulation method and a preparation method thereof, and belongs to the field of terahertz emission. The spin terahertz emitter is a three-layer structure including a ferromagnetic material layer, a non-ferromagnetic material layer and an antiferromagnetic layer. The antiferromagnetic layer adopts a preset crystal phase NiO single crystal antiferromagnetic material, CrSb or Mn3Sn. Under the irradiation of a femtosecond laser, the antiferromagnetic layer generates a laser impact magnetic moment. The precession of the laser impact magnetic moment generates a spin polarization current. The spin polarization current is injected into the non-ferromagnetic layer to generate a transient charge current, and then radiate terahertz, thereby realizing efficient spin terahertz radiation. Further, the magnetic moment direction of the ferromagnetic material layer in the spin terahertz emitter is reversed by rotating the direction of an external magnetic field or by a spin-orbit moment effect, thereby realizing efficient regulation of terahertz chirality.

To provide a technology advantageous for communication using terahertz waves. [Solution] The system includes a reference signal oscillator that generates a first signal at a first frequency, an injection-locked oscillator that generates a second signal at a second frequency in the terahertz band in synchronization with the first signal, and a modulation unit that generates a fourth signal at a fourth frequency from the second signal and a third signal at a third frequency that corresponds to a signal supplied from a baseband circuit.

The invention discloses a terahertz pulse width regulation and control method based on Co / Ru heterojunction, and belongs to the technical field of terahertz photoelectrons. The method comprises the steps of substrate treatment, Co / Ru heterojunction thin film preparation, terahertz emission and detection light path establishment, signal acquisition and treatment and pulse width regulation and control. Sequentially depositing a Co layer and a thickness-adjustable Ru layer on the substrate through magnetron sputtering to form a Co / Ru heterojunction; a femtosecond laser is utilized to excite a heterojunction to generate terahertz pulses, an electro-optical sampling system is utilized to collect time domain signals, and Hilbert transform is adopted to extract pulse width and delay time; based on the monotonic corresponding relation between the thickness of the Ru layer and the terahertz pulse width, continuous adjustment of the pulse width within the range of 100-500 fs is achieved by adjusting the thickness of the Ru layer, and meanwhile the spectral bandwidth and the peak delay time are synchronously regulated and controlled.

This invention belongs to the field of terahertz wave application technology, and particularly relates to a multi-parameter collaborative compensation method for optimizing the output power of a high-power terahertz source. This optimization method fully considers the pump laser parameters of the high-power laser output, the efficiency reduction caused by heat accumulation due to high repetition frequency, and even crystal damage. It formulates a failure contingency plan for core components. Based on the analysis of the factors affecting the output power of the lithium niobate high-power terahertz source, it proposes a multi-parameter iterative collaborative optimization process, which solves the problems of low energy conversion efficiency, easy crystal damage, and difficulty in improving output power caused by the traditional tilted pulse leading-edge pumping method combined with high average power laser pumping. It achieves the goal of stably and reliably generating high-power terahertz radiation under high-power laser pumping.

The invention provides a photoelectric oscillator and a signal processing method. The invention relates to the technical field of photoelectricity, and in the photoelectric oscillator, an electro-optical modulator, a photoelectric detector, a first filter and a power divider form a photoelectric oscillation loop. Compared with a conventional single-passband filter, the first filter in the photoelectric oscillation loop has the advantages that a low-frequency passband is added, and a pulse sequence of the low-frequency passband and a band-pass passband can be excited in the photoelectric oscillation loop. Due to the fact that oscillation of the pulse signal can automatically narrow the pulse sequence to form the ultra-short pulse sequence, on the premise that the pulse sequence excited by the band-pass passband passes through an oscillation mechanism in the photoelectric oscillation loop to narrow the pulse, the pulse sequence excited by the low-frequency passband can further narrow the pulse, and the ultra-short pulse sequence is formed. Therefore, the photoelectric oscillator can generate a microwave pulse sequence which is shorter than that of a conventional photoelectric oscillator, namely an ultra-short microwave pulse sequence.

The invention provides a heterogeneous integrated chip capable of simultaneously generating a low-noise microwave signal and a pulse optical signal, and relates to the technical field of optical communication and the technical field of microwaves. The heterogeneous integrated chip comprises an electric chip layer, a silicon switching layer and an optical chip layer which are stacked, the optical chip layer comprises a micro-ring resonator and is used for outputting a pulse optical signal and adjusting the oscillation speed of the output pulse optical signal through the micro-ring resonator; the electric chip layer comprises an electric filter and is used for outputting a microwave signal and adjusting the frequency of the output microwave signal through the electric filter; and the silicon switching layer is used for integrating the optical chip layer and the electric chip layer. Through oscillation enhancement of the photoelectric double loop and double filtering of the micro-ring resonator and the electric filter, high-quality pulse optical signals and microwave signals can be output at the same time, the integration degree is high, and the size and power consumption are small.

The invention relates to a V-band high-power microwave oscillator based on distributed extraction, a solenoid magnetic field is electrified to generate a magnetic field, under the guidance of the magnetic field, an electron beam is transmitted into a drift tube, and is transmitted to two sections of V-band slow wave structure areas of an internal coaxial electromagnetic structure along the axial direction; in the area of the first section of slow wave structure, the beam and the wave are synchronized to enable the beam to generate speed modulation, the speed modulation obtained by the beam in the first section of slow wave structure is converted into density modulation in the drift cavity through drift motion, finally, the electron beam and the coaxial slow wave structure generate beam-wave action in the second section of slow wave structure, energy is given to a microwave field, and therefore HPM is generated. The second coaxial microwave output waveguide is communicated and coupled with the seventh slow-wave structure period and the twelfth slow-wave structure period of the second section of slow-wave structure, so that a part of energy given to microwaves by electron beams is output from the second coaxial microwave output waveguide, and the distributed extraction effect is achieved; and the power capacity of the device is effectively improved.

The invention discloses an ultrafast photoconductive material structure which is characterized in that the ultrafast photoconductive material structure comprises a substrate layer and a rare earth doped In1-x-yGaxAlyAs semiconductor function layer, in the rare earth doped In1-x-yGaxAlyAs semiconductor function layer, rare earth materials are distributed in an island-shaped structure, and the rare earth materials are arranged in a multi-layer shape parallel to the substrate layer. A rare earth material is co-deposited into an In < 1-x-y > Ga < x > Al < y > As semiconductor, so that the material has excellent carrier mobility and dark resistivity while an ultrafast unbalanced carrier capturing process is realized. The invention further discloses a terahertz photoconductive device based on the structure, and terahertz emission and detection devices based on a photoconductive antenna can be achieved.

This application relates to the field of optical communication, providing a terahertz wave generator and its fabrication method. The generator includes a substrate and a substrate-supported terahertz wave generating structure. The terahertz wave generating structure includes a first waveguide and a second waveguide made of metal. The second waveguide includes a first periodic structure and a second periodic structure. The first waveguide is disposed between the first and second periodic structures. Both the first and second periodic structures have periodically distributed notches along the direction of the first waveguide on their sides closest to the first waveguide. When a first signal light and a second signal light illuminate the cross-section of the terahertz wave generator, the first and second signal lights are frequency-differentialized to generate a terahertz wave, which propagates along the surface of the second waveguide. The terahertz wave generator provided in this application can generate terahertz waves from existing signal light, has a simple and easy-to-implement structure, and utilizes the high conversion efficiency of existing signal light, enabling the generation of more effective terahertz waves.

The application discloses a kind of adjustable terahertz wave sources based on soliton mode-locked fiber laser resonant sideband, including sequentially arranged fiber laser, fiber amplifier, aspheric lens, photoconductive antenna and terahertz wave filter along optical path, the lens is bonded at the back of the photoconductive antenna, fiber laser is connected with fiber amplifier, the light output by fiber amplifier enters aspheric lens, the output beam of aspheric lens is irradiated on photoconductive antenna, and outputs electrical signal, and terahertz wave is filtered out after electrical signal passes through terahertz wave filter.The application utilizes the tunability of resonant sideband spacing in soliton mode-locked fiber laser, and obtains adjustable terahertz signal by optical mixing, avoids the complexity of the previous terahertz wave generation system pumped by two lasers, and the instability of output terahertz wave caused by double-wavelength laser as pump source, so that the system structure is more compact, adjustment is convenient, and the conversion efficiency of optical to terahertz wave of terahertz wave generation system is improved.

The invention discloses a GaN-based high-power terahertz photoconductive emission system, and relates to the technical field of terahertz technology and radio communication. Comprising a terahertz photoconductive emitter, a bias driving module and an ultraviolet femtosecond pumping module, wherein the terahertz photoconductive emitter comprises a Si-GaN photoconductive substrate and a coplanar strip line electrode structure; the ultraviolet femtosecond pumping module is used as a pumping source, laser irradiates the Si-GaN light guide substrate, and free carriers are excited; the bias driving module is used for driving the free carriers to move at a saturation speed to form instantaneous surge current; and the terahertz photoconductive emitter is used for radiating high-power terahertz waves from the instantaneous surge current through a coplanar strip line electrode structure. The terahertz wave emitter is used for breaking through the performance bottleneck of a traditional emitter and improving the generation efficiency of terahertz waves.

The invention relates to the technical field of detector and antenna monolithic integration and a Fabry-Perot resonant antenna, and discloses a millimeter wave / terahertz emitter structure based on a detector and a Fabry-Perot resonant antenna, a chip of a PD monolithic integration broadband patch antenna is arranged in a Fabry-Perot resonant cavity, a PD is fixed on a metal cavity grounding plate, and the detector and the Fabry-Perot resonant antenna are arranged in the Fabry-Perot resonant cavity. The broadband patch antenna faces the partial transmission dielectric plate. The antenna is high in integration level, can remarkably improve the radiation intensity in the main beam direction, and achieves high-gain and high-directivity radiation output.

One embodiment includes a terahertz (THz) optoelectronic device configured to generate and detect THz waves at frequencies ranging from 40 GHz to 10 THz through photomixing when illuminated with an optical beam with more than one wavelength is provided. The device comprises a substrate composed of quantum well layers embedded in an intrinsic region of a PIN photodiode.