Abstract: A multi-port laser device used to create multiple laser induced plasma filaments positioned in a useful position in spatial relationship to another filament or filaments, such as interconnecting with each other.

Abstract: A self-assembling element fabricated using integrated circuit techniques may provide a small diameter helical conductor surrounding an electron beam for the construction of a vacuum electronic device such as a traveling-wave tube for terahertz scale signal.

Abstract: A microwave plasma equipment and a method of exciting plasma are disclosed. The microwave plasma equipment includes: a plasma reaction device having a cavity in which a base support and a plasma-forming area is provided; a conversion device having gradient electrodes, the gradient electrodes being disposed inside the cavity and configured to generate a gradient electric field in the plasma-forming area; a gas supply device configured to introduce gas into the cavity of the plasma reaction device; and a microwave generating device configured to generate and transmit microwave into the cavity of the plasma reaction device.

Abstract: In one aspect, the present invention provides a method of generating an electron beam in a transmission electron microscopy device. The method includes: generating an electron pulse [306] by a pulsed electron source [300], accelerating the electron pulse in a first resonant microwave cavity [302], passing the accelerated electron pulse through a drift space [314], and correcting the energy spread of the accelerated electron pulse in a second resonant microwave cavity [304] by operating it out of phase by 90 degrees from the first resonant cavity [302].

Abstract: A variable-pulse-shape pulsed-power accelerator is driven by a large number of independent LC drive circuits. Each LC circuit drives one or more coaxial transmission lines that deliver the circuit's output power to several water-insulated radial transmission lines that are connected in parallel at small radius by a water-insulated post-hole convolute. The accelerator can be impedance matched throughout. The coaxial transmission lines are sufficiently long to transit-time isolate the LC drive circuits from the water-insulated transmission lines, which allows each LC drive circuit to be operated without being affected by the other circuits. This enables the creation of any power pulse that can be mathematically described as a time-shifted linear combination of the pulses of the individual LC drive circuits. Therefore, the output power of the convolute can provide a variable pulse shape to a load that can be used for magnetically driven, quasi-isentropic compression experiments and other applications.

Abstract: A reflector device having first and second reflector plates to which a reflective surface is attached, respectively, at a prescribed angle of inclination in relation to an axis of rotation, wherein the first reflector plate (1) and the second reflector plate are positioned so as to face one another, and the first reflector plate and/or the second reflector plate are/is capable of rotating around the axis of rotation.

Abstract: An integrated pressurized electronic power amplifier circuit including a plasma cathode structure and beam focusing approach leading to an electron beam, an interaction region; an input signal line for conducting an input signal into the interaction region; an output signal line for conducting an output signal from the interaction region; a collector for the electron beam; and an envelope for maintaining a pressurized ambient and a substrate for selected spatial alignment and thermal management; and wherein the plasma cathode structure generates a plasma as a source of electrons. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.

Abstract: The disclosure relates to systems and methods for interleaving operation of a standing wave linear accelerator (LINAC) for use in providing electrons of at least two different energy ranges, which can be contacted with x-ray targets to generate x-rays of at least two different energy ranges. The LINAC can be operated to output electrons at different energies by varying the power of the electromagnetic wave input to the LINAC, or by using a detunable side cavity which includes an activatable window.

Abstract: A cylindrical waveguide with a mode converter transforms a whispering gallery mode from a gyrotron cylindrical waveguide with a helical cut launch edge to a quasi-Gaussian beam suitable for conveyance through a corrugated waveguide. This quasi-Gaussian beam is radiated away from the waveguide using a spiral cut launch edge, which is in close proximity to a first mode converting reflector. The first mode converting reflector is coupled to a second mode converting reflector which provides an output free-space HE11 mode wave suitable for direct coupling into a corrugated waveguide. The radiated beam produced at the output of the second mode converting reflector is substantially circular.

Abstract: An electrode of an inductive output tube (IOT) is provided with channels for guiding cooling fluid. In one aspect of the invention, the channels are in a confronting relationship with a jacket surrounding the electrode and spaced from the electrode so as to define an interior region. Cooling fluid such as oil is circulated in the channels in fluid communication with the interior region, providing an escape mechanism for trapped bubbles in order to prevent localized heating of the electrode. In another aspect of the invention, the channels form multiple intersecting helical patterns of different pitches, with the steeper-pitched channels providing a more direct escape route for the bubbles.

Abstract: An accelerator for charged particle may include: a capacitor stack which includes a first electrode that can be brought to a first potential, a second electrode that is concentric to the first electrode and can be brought to a second potential differing from the first potential, and at least one intermediate electrode that is concentrically arranged between the first electrode and the second electrode and can be brought to an intermediate potential lying between the first potential and the second potential; a switching device to which the electrodes of the capacitor stack are connected and which is designed such that the concentric electrodes of the capacitor stack can be brought to increasing potential stages during operation of the switching device; a first and a second acceleration channel formed by first and second openings in the electrodes of the capacitor stack such that charged particles can be accelerated along the first and second acceleration channel by means of the electrodes; and a device which c

Abstract: Various embodiments of a coupled cavity traveling wave tube are disclosed herein. For example, some embodiments provide a coupled cavity traveling wave tube including a plurality of core segments arranged in spaced-apart fashion to form an electron beam tunnel, a first longitudinal member adjacent the plurality of core segments alternately extending toward and receding from successive core segments, and a second longitudinal member adjacent to the plurality of core segments alternately extending toward and receding from successive core segments. The first and second longitudinal members are offset to extend toward different core segments.

Abstract: A coaxial cavity gyrotron with two electron beams includes an electron gun (magnetron injection gun, “MIG,” with two beams), a coaxial beam-wave interaction cavity and an outer magnetic field tube. The coaxial beam-wave interaction cavity consists of two parts: an outer conductor and an inner conductor. The two hollow electron beams produced by the MIG are located between the outer conductor and the inner conductor. The MIG includes inner and outer anodes, with a single cathode located between the anodes. The cathode further includes two emitter rings which produce the two hollow electron beams. The entire gyrotron is immersed in the magnetic field tube such that the magnetic field profile is the same or similar to that for a coaxial gyrotron with one electron beam.

Abstract: A mode-selective interactive structure for gyrotrons includes a plurality of metal tubes, wherein an inner wall of each metal tube forms a waveguide; and between each adjacent pair of the metal tubes exists a slice with a first interface and a second interface and when an electromagnetic wave comprising an operating mode and a competing mode propagates through the slice, the competing mode is partially reflected upon, partially transmitted through and/or absorbed at the first interface and the second interface of the slice so that the power loss of the competing mode is larger than the operating mode and the production of the competing modes is suppressed progressively thereby achieving mode selection.

Abstract: A solid state Klystron structure is fabricated by forming a source contact and a drain contact to both ends of a conducting wire and by forming a bias gate and a signal gate on the conducting wire. The conducting wire may be at least one carbon nanotube or at least one semiconductor wire with long ballistic mean free paths. By applying a signal at a frequency that corresponds to an integer multiple of the transit time of the ballistic carriers between adjacent fingers of the signal gate, the carriers are bunched within the conducting wire, thus amplifying the current through the solid state Klystron at a frequency of the signal to the signal gate, thus achieving a power gain.

Abstract: A terahertz sheet beam klystron (TSBK) includes an electron gun configured to generate a sheet electron beam and a drift tube through which the sheet beam is propagated. The drift tube is provided with multiple resonant cavities and includes a drift tube circuit including an input RF circuit through which an input RF signal is introduced and an output RF circuit through which an output RF signal is extracted, a collector, and a vacuum envelope. The output RF circuit is configured such that Qe (extraction Q) of the drift tube circuit is comparable to Q0 (unloaded Q) of the drift tube circuit, thereby improving the efficiency of the drift tube circuit.

Abstract: A radiant tube (4) for guiding a charged particle stream (10) has a hollow cylindrical isolation core (6) directly encompassing a beam-guiding hollow volume (8). The isolation core (6) is formed from a dielectrically acting carrier substrate (14) and an electrical conductor (16) held therein. The conductor (16) is divided into a plurality of conductor loops (20) completely encompassing the circumference of the isolation core (6) at different axial positions of the isolation core (6). The conductor loops (20) are galvanically connected to each other.

Abstract: An output circuit for a microwave tube is provided that has generally high interaction impedance for good efficiency, has high average power capability, and is physically large for a given operating frequency. The output circuit is designed to operate in conjunction with an off-axis, bunched electron beam. Electromagnetic fields are applied to the region in which the electron beam propagates to impart an azimuthal velocity to the bunched electron beam. The electron bunches then interact synchronously with a resonant output structure to excite radio-frequency modes from which energy can be extracted and applied to a load.

Abstract: The present invention includes a Zener diode connected between a helix electrode and an anode electrode, a transistor that closes or opens a circuit between a cathode and an anode of the Zener diode, a photocoupler for turning ON/OFF the transistor through a phototransistor, a first switch for supplying or cutting off a DC voltage for the photodiode of the photocoupler, a capacitor to which the DC voltage that is to be supplied to the photodiode is applied and a control unit that turns ON the first switch beforehand to apply a DC voltage to the photocoupler and the capacitor and that turns OFF the first switch simultaneously with an application of a helix voltage.

Abstract: A grid component for use with a vacuum electron device (VED), such as an inductive output tube (IOT), includes a skirt that adds structural support and aids in alignment. The grid component has a dome in which a grid pattern is formed and includes an annular, concentric flange surrounding the dome. The skirt is formed concentrically around the flange. Alignment orifices may be provided in the flange for passage of alignment pins in the assembled product. The grid, flange, and skirt are a unitary component and are formed by a chemical vapor deposition (CVD) or similar process, in which a mandrel is used to provide a deposition surface. The mandrel is placed in a furnace, and a high-temperature CVD process is used to break down a hydrocarbon gas to thereby deposit a pyrolytic graphite coating onto the mandrel. The mandrel may include a skirt template to provide the characteristic skirt.

Abstract: Disclosed are systems and methods for separating a sheet of glass by directing a microwave beam and a laser beam at a sheet of glass to propagate a crack across the sheet. A laser beam spot formed on the glass sheet by the laser at least partially overlaps a microwave beam spot produced on the sheet by the microwave beam and can be used to generate an increased power density in the overlap region, thereby forming a preferential direction for crack propagation.

Abstract: In various representative aspects, the present invention provides systems and methods for waveguides. A waveguide may comprise a housing and a plurality of reflective surfaces configured to couple to the housing. The housing may be configured to couple to an electromagnetic wave beam generator. The electromagnetic wave beam generator may, be configured to provide a wave beam having a polarization substantially similar to its initial polarization. At least one of the plurality of reflective surfaces may be configured to convert the mode of an incident wave beam. The plurality of reflective surfaces may be configured for alignment in a waveguide.

Abstract: In various representative aspects, the present invention provides systems and methods for waveguides. A waveguide may comprise a housing and a plurality of reflective surfaces configured to couple to the housing. The housing may be configured to couple to an electromagnetic wave beam generator. The electromagnetic wave beam generator may, be configured to provide a wave beam having a polarization substantially similar to its initial polarization. At least one of the plurality of reflective surfaces may be configured to convert the mode of an incident wave beam. The plurality of reflective surfaces may be configured for alignment in a waveguide.

Abstract: A power supply apparatus for a traveling-wave tube includes an electrical discharge switch and a first resistor that are serially connected, and that are connected between a cathode electrode and a first collector electrode; N (N denotes a positive integer) arresters that are serially connected, and that are inserted between a ground potential and a connection node of the electrical discharge switch and the first resistor; N second resistors that are inserted between the N arresters and a second collector electrode to an Nth collector electrode and a ground potential, respectively; and an electrical discharge control circuit that turns off the electrical discharge switch at a time of normal operation of the power supply apparatus and turns on the electrical discharge switch when stopping operation of the power supply apparatus.

Abstract: An electron beam tube (17) having a longitudinal axis comprises a first component, such as a ceramic wall (5) and a second component such as a drift tube assembly having a mounting plate (3). The tube further comprises means, such as member (18), arranged to allow relative sliding movement of the first component relative to the second component in a radial direction. The invention helps to alleviate mechanical stresses caused by differential thermal expansion of the components.

Abstract: A resonant cavity with a bowtie shape supports an electromagnetic field used to deflect the trajectory of an electron beam passing through the cavity. The short transit time of the beam across the gap maintains the cavity fields at near-optimal phase, improving interaction efficiency even for relatively low-energy beams. High interaction impedance ensures good drive-power-to-deflection conversion efficiency. The uniform field achieved across the gap enforces uniform deflection across the beam profile to maintain beam quality. Multiple bowtie cavities can be arranged to allow arbitrary two-dimensional deflections.

Abstract: An output circuit for a microwave tube is provided that has generally high interaction impedance for good efficiency, has high average power capability, and is physically large for a given operating frequency. The output circuit is designed to operate in conjunction with an off-axis, bunched electron beam. Electromagnetic fields are applied to the region in which the electron beam propagates to impart an azimuthal velocity to the bunched electron beam. The electron bunches then interact synchronously with a resonant output structure to excite radio-frequency modes from which energy can be extracted and applied to a load.

Abstract: An electron beam tube device such as an inductive output tube of the integral cavity type has a RF window which re-enters the interaction space within the cavity thereby defining a space that is within the interaction cavity but is outside the vacuum. An output coupler in the form of an output coupling loop protrudes into this space and thus couples with the electromagnetic field within the interaction space, whilst remaining outside the vacuum envelope. This allows the coupling loop to be adjusted without any additional seal arrangement between the coupling loop and walls of the output cavity.

Abstract: In an electron accelerator, a conductive housing defines a cavity. Photoelectrons are emitted from a photocathode into the cavity when light is applied to the photocathode. Via an opening formed in a wall of the conductive housing, the photoelectrons are output to the outside of the cavity. Coolant is flowed through a flow path formed in the wall of the conductive housing, to suppress a temperature rise of the conductive housing. The wall of the conductive housing is made by a metal additive manufacturing technique in such a way as to produce a flow path that has a gentle trajectory without discontinuities in gradient.

Abstract: A device is proposed for producing high-frequency microwaves, having a cathode arrangement with heatable cathodes for emitting electrons, two grating arrangements for controlling and focusing the electrons flow and an anode for recaiving the electrons passing through the grating arrangements. The cathode arrangement and the first grating arrangement and also a blocking or choke element define an output cavity forming a resonance cavity and the anode and the second grating arrangement define an output cavity likeeise forming a resonance cavity. The cathode arrangement has a monuting for the cathode such that deformation of the cathode with reduction of the spacing between the heatable cathode and grating is avoided.

Abstract: A method and apparatus for accelerating charged particles are disclosed, wherein the method comprises using at least a transverse component of a temporally and spatially shaped electromagnetic field to accelerate one or more charged particles.

Abstract: A microscale vacuum electronic device (10) provides for a mechanical modulation of cathode (12) position allowing improved high-frequency modulation of an electron beam (24) useful for vacuum electronic devices such as klystrons, klystrodes, and high frequency triodes.

Abstract: The invention provides an electron beam device 1 comprising at least one field emission cathode 3 and at least one extracting electrode 5, whereby the field emission cathode 5 comprises a p-type semiconductor region 7 connected to an emitter tip 9 made of a semiconductor material, an n-type semiconductor region 11 forming a pn-diode junction 13 with the p-type semiconductor region 7 a first electric contact 15 on the p-type semiconductor region 7 and a second electric contact 17 on the n-type semiconductor region 11. The p-type semiconductor region 7 prevents the flux of free electrons to the emitter unless electrons are injected into the p-type semiconductor region 7 by the pn-diode junction 13. This way, the field emission cathode 3 can generate an electron beam where the electron beam current is controlled by the forward biasing second voltage V2 across the pn-diode junction. Such electron beam current has an improved current value stability.

Abstract: A linear electron beam tube comprises an electron gun having a cathode and a grid, and an anode arranged in a first portion of a drift tube. The drift tube is within a vacuum envelope and has first and second portions separated by a gap at which point an electron beam, density modulated with an input RF signal is inductively coupled to an output cavity. The vacuum envelope is partially defined by a cylindrical ceramic wall and a pair of ferromagnetic pole pieces at its ends that form a DC magnetic circuit. The pole pieces extend radially beyond the vacuum envelope. At least those parts of the surface of the pole pieces that are in the RF path are coated with a layer of relatively low RF loss material such as copper. A balance ring separates the ceramic from the pole pieces.

Abstract: In a channel spark source triggered by gas discharge for generating a stable focused electron beam, a gas supply for a hollow cathode thereof is provided which generates in the hollow cathode a pressure differential so that the multiplication of charge carriers in a trigger plasma of a trigger plasma source connected to the hollow cathode provides for a reliable gas discharge and the formation of a stable electron beam which exits the arrangement and which does not damage the internal passages of the arrangement.

Abstract: A multibeam, electrostatically focused klystron includes a plurality of conductive members, ones of which are recessed to provide input and output sections of microwave cavities, wherein focusing voltage is applied between those sections. The conductive members are either spaced along the path of multiple beams, or stacked in insulated relation, in either case being supported by glass rods within a glass envelope.

Abstract: A method and apparatus for accelerating charged particles. The charged particles accelerate as they travel through electric fields produced by a plurality of accelerating elements having first and second electrode plates. A magnetic field produced by a pair of magnets causes the charged particles to travel in a generally circular orbit.

Abstract: The invention relates to amplifying electron tubes operating at microwave frequencies. The electron tube comprises: a pump-out tube that allows the vacuum inside the electron tube to be created; an electron gun that emits an electron beam inside the electron tube; a collector that directly collects a first portion of the electron beam. The pump-out tube directly repels a second portion of the electron beam in the direction of the collector.

Abstract: An oscillator includes an amplifier having an input and an output, a feedback network connected between the input of the amplifier and the output of the amplifier, the feedback network being configured to provide suitable positive feedback from the output of the amplifier to the input of the amplifier to initiate and sustain an oscillating condition, and a tuning circuit connected to the input of the amplifier, wherein the tuning circuit is continuously variable and consists of solid state electrical components with no mechanically adjustable devices including a pair of diodes connected to each other at their respective cathodes with a control voltage connected at the junction of the diodes.

Abstract: In a power-supply unit for a microwave tube, voltage between a helix power supply terminal and a cathode power supply terminal is divided into voltage slightly lower than the voltage of a collector power supply terminal. Uni-directional conductive means is provided between a voltage dividing point and the collector power supply terminal, and when the voltage of the collector power supply terminal is about to be lower than voltage at the voltage dividing point while the voltage approximates the voltage of the cathode power supply terminal, the uni-directional conductive means conducts and clamps the voltage of the collector power supply terminal so that the voltage is substantially equal to the voltage at the voltage dividing point.

Abstract: A microminiature microwave electron source excited by a pulsed microwave power through a coaxial to emit electrons includes an electrically conductive chamber that is connected to an external conductor of the coaxial cable at an openings end thereof and has an opening anode in a bottom portion thereof, a central conductor adjacent to the electron source, the central conductor having one end thereof connected to a central conductor of the coaxial cable, a carbon nanotube cold cathode formed on the other end thereof being supported by the chamber such that the cold cathode opposes the anode, a coupling iris that airtightly and fixedly supports the central conductor at an opening end of the chamber, and a connecting device for electrically and mechanically connecting the opening end of the chamber to the central conductor of the coaxial cable so as to connect the central of the electron source to the central conductor of the coaxial cable.

Abstract: In a power-supply unit for a microwave tube, voltage between a helix power supply terminal and a cathode power supply terminal is divided into voltage slightly lower than the voltage of a collector power supply terminal. Uni-directional conductive means is provided between a voltage dividing point and the collector power supply terminal, and when the voltage of the collector power supply terminal is about to be lower than voltage at the voltage dividing point while the voltage approximates the voltage of the cathode power supply terminal, the uni-directional conductive means conducts and clamps the voltage of the collector power supply terminal so that the voltage is substantially equal to the voltage at the voltage dividing point.

Abstract: A wiggler that, when used in a free electron laser, reduces the harmonicity of the light emitted from the free electron laser. In general, the reduced harmonicity is accomplished by making the magnetic field distribution of the wiggler to be sinusoidal, rather than like a square wave. The sinusoidal magnetic field distribution reduces the number of harmonics that can be used to approximate the magnetic field distribution of the wiggler, and thus reduces the harmonicity of the light produced by passing an electron beam through the wiggler. In a particular embodiment, the wiggler is composed of pieces or segments of permanent magnets that are arranged along an axis such that their magnetic orientations are perpendicular to the axis, and such that the magnetic field distribution along the axis is sinusoidal.

Abstract: A collector core of a microwave tube has an insulator and a radiator around a cylindrical outer peripheral portion thereof. The cylindrical insulator and radiator comprise a slit along a central axis of the collector core, respectively. These slits are arranged on mutually overlapped positions. Portions of the collector core corresponding to these slits are cut off so as to be flat or concave. These slits and the flat surface or the concave portion are arranged symmetrically in a section of the collector core.

Abstract: Disclosed is a novel hybrid wiggler as a kind of insertion devices, for example, in an electron accelerator. Different from a conventional hybrid wiggler consisting of two oppositely facing arrays each formed of an alternate arrangement of a plurality of permanent magnet blocks and a plurality of pole pieces of a soft magnetic material to generate a sine-curved periodical magnetic field in the gap space between the arrays to cause meandering of electron beams, each of the pole pieces is sandwiched on the lateral surfaces with a pair of auxiliary permanent magnet blocks so that the periodical magnetic field generated in the gap space can be greatly strengthened.

Abstract: A cathode-ray tube includes a plate having a first hole on a first surface of the plate and a second hole on a second surface of the plate. The first and second holes coupled together to allow electron beams to pass therethrough. The plate is a unitary structure. The first hole is formed by initiating a first hole formation from the first surface, and the second hole is formed by initiating a second hole formation from the second surface. The first surface is on an opposing side of the second surface.

Abstract: A microwave/DC converter employing fast cyclotron wave of the electron beam. Coupling section for feeding energy into the electron beam contains two microwave cavities 3, 7. The second cavity 7 has a group of 2n (where n=2, 3, . . . ) rod electrodes aligned symmetrically in parallel around the axis for giving the electron beam a rotational movement around the axis according to the microwave power P and receives the electron beam already slightly modulated by the first cavity 3, which is a resonant coupler with uniform transverse electric field and operates at 1/n-th of the second resonant cavity frequency (attached Figure shows the case of n=2). For the effective interaction in both cavities 3, 7 uniform static magnetic field corresponds to the cyclotron frequency equal to a half of external microwave power source frequency. Asymmetrically reversed magnetic field is used between microwave cavities and collector to achieve the maximal efficiency of the microwave energy conversion into DC energy.

Abstract: A multibeam electron tube with several approximately parallel electron beams passing through a body. Among the beams, at least some define an interbeam volume, each beam defining the interbeam volume being subjected to a perturbing azimuthal magnetic field induced by all the other beams. The tube includes an element allowing, in at least one conducting element located in the interbeam volume, flow of a reverse current in the opposite direction to that of the current of the beams, this reverse current generating, in the beams defining the interbeam space, a magnetic correction field whose purpose is to oppose the perturbing magnetic field. Exemplary embodiments of the present invention especially apply to the multibeam klystrons or traveling wave tubes.

Abstract: The present invention pertains to an electron gun that generates multiple electron bunches and the application of this gun to produce rf energy. The electron gun comprises an rf input cavity having a first side with multiple emitting surfaces and a second side with multiple transmitting and emitting sections. The gun is also comprised of a mechanism for producing a rotating and oscillating force which encompasses the multiple emitting surfaces and the multiple sections so electrons are directed between the multiple emitting surfaces and the multiple sections to contact the multiple emitting surfaces and generate additional electrons and to contact the multiple sections to generate additional electrons or escape the cavity through the multiple sections. The multiple sections preferably isolates the cavity from external forces outside and adjacent the cavity. The multiple sections preferably include multiple transmitting and emitting grids.

Abstract: An adaptive heater voltage algorithm and control system for setting and maintaining a vacuum electron device (VED) heater voltage, such as that of a klystron. An algorithm and control system are disclosed that sets and maintains the VED's cathode at the lowest temperature required for 98% of the beam current that corresponds to a fully space charge limited (FSCL) operation. VED lifetime is dependent upon cathode temperature, and in general, a cooler cathode will last longer. The optimum heater voltage corresponds to the beam current that is 98% of the beam current during FSCL operation. As the VED ages and the cathode becomes depleted, the heater voltage will need to be gradually increased to maintain the 98% FSCL value. There are, therefore, two stages to the adaptive heater voltage algorithm—(1) initial determination of the heater voltage and (2) the determination of the heater voltage during amplifier operation.