87 results about "Undulator" patented technology

The invention discloses a multi-purpose synchrotron radiation coherent X-ray diffraction microscopic imaging device. A synchrotron radiation X-ray light source, an undulator, a monochromator crystal, an X-ray shutter, a first lifting platform, a focusing device cavity, a vacuum piping, a second lifting platform, a multi-purpose sample room, a vacuum piping, a third lifting platform, a detector, and a computer which is used for collecting data and controlling an electric controlled translation platform are sequentially and coaxially arranged along the forward motion direction of light beam, wherein the monochromator crystal, the X-ray shutter and the first lifting platform are arranged on an electrical rotary platform, the focusing device cavity, the vacuum piping and the second lifting platform are arranged on the first lifting platform, the multi-purpose sample room, the vacuum piping and the third lifting platform are arranged on the second lifting platform, and the detector and the computer are arranged on the third lifting platform. According to the multi-purpose synchrotron radiation coherent X-ray diffraction microscopic imaging device, a low vacuum operating mode, a ventilation working mode, a freezing operating mode, X-ray focusing mode imaging or X-ray non-focusing mode imaging are achieved, the collection of three-dimension diffraction signals of samples are achieved by using a three-dimension rotating platform, a high quality three-dimension rebuilding result is obtained by using computer software, dying treatment and slicing treatment to the samples are needless, and train of thought is supplied to enrich a synchrotron radiation beam line imaging method.

The invention discloses a free electron laser based tunable narrow-band compact terahertz radiation source. The free electron laser based tunable narrow-band compact terahertz radiation source comprises a laser source, a pulse accumulation light path, a reflecting mirror, a photocathode multi-cavity microwave electron gun, a solenoid coil and an undulator, wherein laser pulses emitted from the laser source are accumulated by n times through the pulse accumulation light path to generate a laser pulse string composed of 2n laser pulses, the laser pulse string irradiates on the surface of a negative electrode of the photocathode multi-cavity microwave electron gun by the reflecting mirror, and an electron bunch string is emitted from the surface of the negative electrode by a photoelectric effect, is accelerated by a microwave field generated by a microwave power source in a chamber of the photocathode multi-cavity microwave electron gun and enters the undulator after being transversely focused by a magnetic field of the solenoid coil so that electromagnetic radiation associated with THz waveband is stimulated. The technical scheme disclosed by the invention has the characteristics of compact structure, continuous and adjustable frequency and narrow bandwidth, and is easy to implement technically.

An undulator includes a periodic arrangement of magnets to produce a periodic spatial magnetic field distribution in a magnetic gap defined by the magnets. The undulator further includes a temperature-compensating material selectively arranged to compensate for a temperature-dependent change in the magnetic field of the undulator. The change may be in the strength of the magnetic field, or in the position of the magnetic field centerline. According to one aspect of the invention, the temperature-compensating material is movably arranged, so as to fine tune its compensation effect after it is initially arranged. Alternatively or additionally, the amount of temperature-compensating material may be adjusted to fine tune its compensation effect after it is initially arranged.

A method and apparatus for implementing dynamic compensation of magnetic forces for undulators are provided. An undulator includes a respective set of magnet arrays, each attached to a strongback, and placed on horizontal slides and positioned parallel relative to each other with a predetermined gap. Magnetic forces are compensated by a set of compensation springs placed along the strongback. The compensation springs are conical springs having exponential-force characteristics that substantially match undulator magnetic forces independently of the predetermined gap. The conical springs are positioned along the length of the magnets.

The invention provides a Praseodymium-Ferrum-Boron permanent magnet and a preparation method of the Praseodymium-Ferrum-Boron permanent magnet. The permanent magnet is made from an alloy with a mass percent represented by Pr<30.3+a+b>Fe<67.16-x-y-z>Cu<x>Nb<y>Al<z>B<1.04>, wherein a+b represents the lost mass percent of praseodymium in oxidization and melting processes; a+b is not larger than 1.5, x is not smaller than 0.15 and not larger than 0.20, y is not smaller than 0.14 and not larger than 0.5, and z is not smaller than 0.4 and not larger than 0.55. The Praseodymium-Ferrum-Boron permanent magnet can achieve high Br and high Hci simultaneously at normal temperature and is excellent in magnetic performance, low in preparation cost, and good in magnetic field stability, magnetic field homogeneity and plating airtightness; the Praseodymium-Ferrum-Boron permanent magnet can realize practical application in the engineering of high-precision low-temperature permanent magnet devices such as cryogenic permanent magnet undulators (CPMU) as well as in the fields of space instruments and meters.

A Free Electron Laser source includes: a fiber-based laser having a plurality of amplifying fibres wherein an initial laser pulse is distributed and amplified, and element for grouping together the elementary pulses amplified in the fibre in order to form an a single amplified global laser pulse; a laser plasma accelerator wherein the global laser pulse generates relativistic electron beams, a beam focusing system transporting electron beams from the laser plasma accelerator, an undulator wherein relativistic electron beams generate an electromagnetic beam, and a beam separator system, wherein the electron beam and the electromagnetic beam are separated.

A laser-driven dielectric electron accelerator is composed of a dielectric photonic crystal accelerator structure having an electron beam channel and buried grating whose elements are arranged linearly parallel to the electron beam channel. The accelerator structure preferably has a thin film material coating. The grating may have an asymmetric structure. The accelerator and undulator structures may be integrated with on-chip optical and electronic devices such as waveguide devices and control circuits so that multiple devices can be fabricated on the same chip.

An array of spatially separated beamlets is produced by a corresponding array of charged particle emitters. Each emitter is at an electrostatic potential difference with respect to an immediately adjacent emitter in the array. The beamlets are converged laterally to form an charged particle beam. The beam is modulated longitudinally with infrared radiation to form a modulated beam. The charged particles in the modulated beam are bunched longitudinally to form a bunched beam. The bunched beam may be modulated with an undulator to generate a coherent radiation output. This abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

A variable-period permanent-magnet undulator which is applicable not only to a planar undulator but also to a helical undulator, in which permanent-magnets and ferromagnetic substances are alternately arranged, and the ferromagnetic substance interposed between the permanent-magnets is saturated to thus enable the magnets to be effectively spaced apart from each other by the repulsive force between the permanent-magnets, thereby adjusting the period of the magnetic field in an easy and precise manner.

The invention provides an undulator. The undulator at least comprises M permanent magnet cycles which are sequentially arranged along the direction to which an electron beam transmits; each permanent magnet cycle is composed of four rows of permanent magnet structures, each row comprising N rows of permanent magnet sets, wherein each row of permanent magnet sets comprises K permanent magnet units; M, N and K are all the natural numbers more than and equal to 1; the permanent magnet structures in the four rows are pairwise coupled and then are oppositely arranged at two sides in the along to which the electron beam transmits and relatively displace to form at least one combined magnetic field through which the electron beam emits elliptically polarized light, circularly polarized light or linearly polarized light in any polarizing angle of 0 to 360 degrees, and the electron velocity direction is deviated from the direction of an axis of the undulator. The undulator has the advantages that either linearly polarized light or elliptically and circularly polarized lights can be produced, and the electron velocity direction is deviated from the direction of the axis of the undulator all the times, so that the thermal load of the synchronously-radiated beam lines can be greatly reduced.

An undulator with a compact construction is provided that reduces weight, complexity and cost. The compact undulator system and methods provides mechanical integrity without compromising magnetic field quality.

The invention relates to a superconducting undulator magnet which comprises two columns of superconducting coil arrays longitudinally arranged at intervals and in parallel. Each column of superconducting coil arrays comprise a coil skeleton with high magnetic conductivity, n+1 magnetic poles which are axially arranged on the coil skeleton with the high magnetic conductivity at intervals, and n groups of coils which are formed by winding a single superconducting wire on the surface of the coil skeleton with the high magnetic conductivity and are positioned every two adjacent magnetic poles, and a direct-current power supply used for supplying the power to the coils, wherein the n represents a natural number; and the leading-in direction and the leading-out direction of the single superconducting wire during a winding process are arranged in a manner of enabling the directions of magnetic fields generated by the two adjacent coils to be opposite. The n groups of coils in each column of superconducting coil arrays are formed by winding the single superconducting wire, so that the running resistance of the n groups of coils is lowered. Thus, the cooling cost is effectively lowered while the running stability is improved at the same time. In addition, the magnetic induction intensity generated by the superconducting undulator magnet can be changed by regulating currents conducted into the coils.

A high power extreme ultraviolet (EUV) beam is produced. An electron beam is injected in a compact electron storage ring configured for emission of free-electron laser (FEL) radiation. The electron beam is passed through a magnetic undulator on each of a plurality of successive revolutions of the electron beam around the compact electron storage ring. The electron beam is induced to microbunch and radiate coherently while passing through the magnetic undulator. A portion of the free-electron laser radiation at an extreme ultraviolet wavelength produced by an interaction of the electron beam through the magnetic undulator is outputted.

Methods and systems for realizing a high brightness, compact x-ray source suitable for high throughput, in-line x-ray metrology are presented herein. A compact electron beam accelerator is coupled to a compact undulator to produce a high brightness, compact x-ray source capable of generating x-ray radiation with wavelengths of approximately one Angstrom or less with a flux of at least 1e10 photons/s*mm^2. In some embodiments, the electron path length through the electron beam accelerator is less than ten meters and the electron path length through the undulator is also less than 10 meters. The compact x-ray source is tunable, allowing for adjustments of both wavelength and flux of the generated x-ray radiation. The x-ray radiation generated by the compact x-ray source is delivered to the specimen over a small spot, thus enabling measurements of modern semiconductor structures.

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 provides a preparation method of a high-performance permanent magnet and a vacuum undulator magnetic structure with the high-performance permanent magnet, wherein the preparation method comprises: S1, providing a permanent magnet 2.0-2.5 mm in magnetizing direction thickness; S2, covering the surface of the permanent magnet with TbF3 powder before placing the permanent magnet in a molybdenum box, subjecting the permanent box to high-temperature grain boundary diffusion, and annealing the permanent magnet; S3, coating the surface of the permanent magnet of step S3 with NiCuNi layer, TiN layer or NiCuTiN layer; S4, subjecting the permanent magnet of step 3 to saturation magnetization; S5, aging the permanent magnet of step S4. The problems of the prior art, such as poor uniformity of intrinsic coercive force in a permanent magnet and zero optimization on orienting thickens of the permanent magnet, are solved.

Passage through LINACs of electron bunches in their acceleration phase is co-ordinated with passage through the LINACs of electron bunches in their deceleration phase. Each successive pair of electron bunches are spaced in time by a respective bunch spacing, in accordance with a repeating electron bunch sequence. The electron source provides clearing gaps in the electron bunch sequence to allow clearing of ions at the undulator. The electron source provides the clearing gaps in accordance with a clearing gap sequence such that, for each of the plurality of energy recovery LINACS, and for substantially all of the clearing gaps:- for each passage of the clearing gap through the LINAC in an acceleration phase or deceleration phase the clearing gap is co-ordinated with a further one of the clearing gaps passing through the LINAC in a deceleration phase or acceleration phase thereby to maintain energy recovery operation of the LINAC.

A method for realizing both high extraction efficiency of laser light from electron beams and femto-second ultra-short pulses in a free-electron laser, wherein the peak current of electron pulses from a superconducting or normal conducting linear accelerator serving as a driver for the free-electron laser is adjusted to be greater than a certain lower limit and electron beams are brought into perfect synchronism with light or the time of duration for which the electron pulses are repeated is made longer than the time to saturation of light oscillation (the time during which light is emitted due to the increase of optical output by an amount corresponding to the gain up to the point where the optical output does not increase any more), whereby the oscillation of light is facilitated, wherein the extraction efficiency of laser light from electron beams is increased to exceed the theoretical limit which is expressed by 1/(2 Nw)˜1/(4 Nw) (Nw=the number of undulator periods) of electron beam power or rendered proportional to the square of N, or the number of electrons in a micropulse, and wherein ultra-short pulses of the femto-second range are generated.

The invention provides a small-sized automatic undulator and a processing method, which has the advantages of reasonableness and convenient use. A finished product can satisfy the requirements of use or drawing paper by only putting raw materials into the small-sized automatic undulator, thereby increasing production efficiency. A feeder is arranged on a ripple forming and punching charging device, the rear part of the ripple forming and punching charging device is connected with a ripple mesh gear propulsion device, and the rear part of the ripple mesh gear propulsion device is connected with a double-side four-edge cutter ripple strip intercepting device. The small-sized automatic undulator has three combination functions: the ripple impact molding, the ripple distance compression forming and the ripple strip are intercepted according to a set wave number, the efficiency is increased greatly, and the work which needs to be completed by three persons originally can be completed by one person.