30results about "Charged particle masers" patented technology

Masers and microwave amplifiers that can function in the continuous-wave mode at room temperature are provided. The maser system can include a diamond gain medium having nitrogen-vacancy centers, and a resonator can be disposed around the gain medium. The resonator can be disposed in a cavity box, and radiation (e.g., visible light) can be provided to the gain medium to cause emission of microwave radiation.

A terahertz imaging system uses a terahertz light source to illuminate a target object with a series of short pulses of terahertz light. The pulses have a low average output power but a high peak output power, thereby enabling imaging of the suspicious object or person at a safe distance while avoiding injury to the person being imaged. For each pulse, the reflection of the light is imaged by a detector array. The terahertz light pulses are individually narrow band and the emitted pulse train is rapidly tuned in wavelength across a wide frequency range in the terahertz band. Within the terahertz frequency range, molecules have unique absorption spectra. The energy reflected from the illuminated threat object is measured for each of the discrete narrow frequency bands and compared to the absorption spectra of known dangerous materials to determine whether the threat object contains or carries a known dangerous material.

A compact system and method are provided for implementing the generation of electromagnetic radiation extending over mm-wavelength to sub-mm-wavelength or terahertz range. The generated electromagnetic radiation can be broadband or have a variable bandwidth. Electrons are accelerated to a chosen energy and undergo subsequent or simultaneous temporal or spatial compression. The degree of compression is chosen such that the electron beam pulse length is near to or less than that of the terahertz wavelength desired to be generated. The radiation is produced by one or combination of methods of synchrotron radiation or transition radiation.

Various embodiments of undulators, methods of fabricating undulators, and systems incorporating undulators are described. Certain embodiments provide a compact, electromagnetic undulator. The undulator may comprise a substrate and one or more electromagnets, which may be formed on the substrate. Certain embodiments have a period not greater than about 5 mm. The undulator may be operatively coupled with a particle accelerator to provide a free electron laser system.

The invention relates to a planar multi-electron-beam excitation graphene sub-wavelength grating-integrated terahertz radiation source and application of the terahertz radiation source. The terahertzradiation source comprises a shell, an electron gun cathode, a grating structure, partition plates, and an output port; the shell is used for protecting the terahertz radiation source; the electron gun cathode is arranged on one side of the opening of the shell and is used for emitting multiple electron beams; the grating structure is arranged in the shell; a graphene layer is arranged on the surface of the grating structure; and the surface plasmon polaritons of the graphene layer interact with the multiple electron beams, so that terahertz radiation can be generated; the partition plates arearranged between every two adjacent electron beams and are used for isolating the electron beams; and the output port is arranged on the shell and is used for outputting the terahertz radiation. According to the terahertz radiation source of the invention, the coupling effect of the electron beams and an integrated high-frequency system is fundamentally enhanced; beam-wave interaction efficiencyis improved; the problems of the low interaction efficiency and low output power which confront the development of a vacuum electronic device towards a terahertz wave band are solved; the output powerof the terahertz radiation source can be greatly improved; and the processing of engineering tubing and the realization of a high-power terahertz source are facilitated.

Provided is a linearly polarized ultra-short terahertz wave generating device which has a parabolic barrel mirror installed at one side of a multiple thin film, to generate an ultra-short terahertz wave having single linear-polarized light and uniformly formed output distribution.

This specification relates to a terahertz pulse generator capable of generating ultra-short terahertz pulses by use of electron beams transported through a plurality of foils. The plurality of foils in a shape of disc are arranged in an overlapped state and form a conical shape that diameters of the disc-shaped foils sequentially decrease along a direction that the electron beam is transported. Coherent radiation, which is generated as the ultra-short electron beam is transported through the foils in respective spaced gaps of the foils, is propagated toward the outside of the disc-shaped foils and gathered with forming a conical wave surface at edges of the disc-shaped foils. This may result in enhancement of generation efficiency of the terahertz waves.

Low power MASER (Microwave Amplification by Stimulated Emission of Radiation) radiation is used to non-invasively record molecular activity in a biological object such as a brain. Low power MASER radiation is also used to neuromodulate molecular targets via Rabi coupling, resulting for example in conformational and function change in specific molecular targets such as ligand-gated ion channels, voltage-gated ion channels, G-proteins, or dopamine receptors. The method can be used to change the energy state of targeted molecules via energization or enervation, or to ablate targeted molecules.

A MASER (Microwave Amplified Stimulated Emission of Radiation) emitter is fabricated of thin film components, including a thin film of nitrogen-implanted, epitaxial crystal diamond. The MASER elements can also include a controllable Q-switching layer and be arranged in a thin panel, phased array to generate a single beam of coherent, mode-locked, continuous wave MASER radiation.

The invention discloses a microwave source and a control method thereof. The microwave source comprises a laser and a loop. The loop comprises a modulation unit, a beam splitting unit, a fiber array,a beam combining unit, a light detector and an amplification unit. The modulation unit modulates the laser signal into a laser signal. The beam splitting unit divides the laser signal into N channelsof light splitting signals with the same frequency. The fiber array converts the N channels of light splitting signals into N channels of light signals with different light paths. The beam combining unit combines the N channels of light signals into one channel of total light signal. The light detector converts the total light signal into an electric signal. The amplification unit is used for amplifying the electric signal to be divided into two channels, wherein one channel of the electric signal is sent to the modulation unit and the other change of the electric signal is outputted. The stray of the microwave signal can be greatly suppressed and the high-quality microwave source with low phase noise can be obtained.

The invention relates to the field of quantum radio physics and is the solid-state quantum generator of nanometer range electromagnetic radiation. It may be widely used in engineering, nanotechnology, physics, biology, chemistry and medicine. The claimed device comprises at least two electric power adjustment devices, at least one phase shifting device, at least one electromagnetic wave emitter, at least two exciting inductors and an excited inductor. It is configured to adjust electrical power in the first and second exciting inductors, allowing to receive electrical signals with equal amplitudes in them.

The invention provides a coherent terahertz radiation generating device based on a compact accelerator. An ultrafast laser of the coherent terahertz radiation generating device is set to generate ultrafast laser pulses; the ultrafast laser, the first beam splitting piece and the first reflecting mirror are sequentially arranged on a first axis in the light path direction, the first beam splitting piece and the compact injector are sequentially arranged in the light path direction, and the first reflecting mirror, the pulse broadening and beam splitting system and the laser modulation system are sequentially arranged in the light path direction; the compact injector generates a high-energy electron beam, and the compact injector, the laser modulation system and the terahertz radiation system are sequentially arranged in the transmission direction of the high-energy electron beam and located on the same horizontal plane. The invention also provides a corresponding coherent terahertz radiation generation method. According to the coherent terahertz radiation generation device, the pulse broadening and beam splitting system and the laser modulation system are utilized to realize effective modulation of high-energy electron beams, and coherent terahertz radiation with high pulse intensity and continuously tunable full terahertz wave bands can be generated.

A terahertz radiator is based on coherent Smith-Purcell radiation amplified by stimulation. The terahertz radiator includes an electron emission source configured to emit electron beams and a pumping source configured to emit pumping signals. The pumping signal interacts with a primary grating structure to obtain preliminarily bunched electrons. The preliminarily bunched electrons interact with the primary grating structure to generate coherent Smith-Purcell radiation. The coherent Smith-Purcell radiation and the pumping signals vertically resonate in a primary resonant cavity structure, so that the electron bunching density is increased, and in turn, the coherent Smith-Purcell radiation is enhanced. A positive feedback process is formed by free electrons and the coherent Smith-Purcell radiation, and the coherent Smith-Purcell radiation amplified by stimulation and periodic bunched electron bunches are obtained. The terahertz radiator can be used to realize a stimulated amplification phenomenon under the conditions of small current and large beam spots.