Abstract: A crossed field device, such as a magnetron or crossed field amplifier, that includes a cathode, an anode, one or more magnetic elements, and one or more extraction elements. In one embodiment, the crossed field device includes an annular cathode and anode that are axially spaced from one another such that the device produces an axial electric (E) field and a radial magnetic (B) field. In another embodiment, the crossed field device includes an oval-shaped cathode and anode that are radially spaced from one another such that the device produces a radial electric (E) field and an axial magnetic (B) field. The crossed field device may produce electromagnetic (EM) emissions having a frequency ranging from megahertz (MHz) to terahertz (THz), and may be used in one of a number of different applications.

Abstract: A crossed field device, such as a magnetron or crossed field amplifier, that includes a cathode, an anode, one or more magnetic elements, and one or more extraction elements. In one embodiment, the crossed field device includes an annular cathode and anode that are axially spaced from one another such that the device produces an axial electric (E) field and a radial magnetic (B) field. In another embodiment, the crossed field device includes an oval-shaped cathode and anode that are radially spaced from one another such that the device produces a radial electric (E) field and an axial magnetic (B) field. The crossed field device may produce electromagnetic (EM) emissions having a frequency ranging from megahertz (MHz) to terahertz (THz), and may be used in one of a number of different applications.

Abstract: A method and apparatus to generate a beam of coherent light including x-rays or XUV by colliding a high-intensity laser pulse with an electron beam that is accelerated by a synchronized laser pulse. Applications include x-ray and EUV lithography, protein structural analysis, plasma diagnostics, x-ray diffraction, crack analysis, non-destructive testing, surface science and ultrafast science.

Abstract: Cost-effective, simple, low-noise, crossed-field devices such as a microwave magnetron, a microwave oven utilizing same, and crossed-field amplifier utilize an azimuthally varying, axial magnetic field. The magnetic configuration reduces and eliminates microwave and radio frequency noise. This microwave noise is present near the carrier frequency and as sidebands, far separated from the carrier. The device utilizes azimuthally-varying, axial, magnetic field perturbations. At least one permanent perturbing magnet having an azimuthally-varying magnetic field impressed thereupon causes the axial magnetic field to vary azimuthally in the magnetron and completely eliminates the microwave noise and unwanted frequencies. Preferably, the number of axial magnetic field perturbations is based on the number of cavities of the magnetron.

Abstract: Low-noise, crossed-field devices such as a microwave magnetron, a microwave oven utilizing same, crossed-field amplifier and a method of converting a noisy magnetron to a low-noise magnetron utilize an azimuthally varying, axial magnetic field. The magnetic configuration reduces and eliminates microwave and radio frequency noise. This microwave noise is present near the carrier frequency and as sidebands, far separated from the carrier. The device utilizes azimuthally varying, axial, magnetic field perturbations. In one embodiment, at least one permanent magnet is placed against the azimuthally-symmetric, axial magnetic field magnetron magnets (four magnets work especially well). This additional permanent magnet(s) causes the axial magnetic field to vary azimuthally in the magnetron and completely eliminates the microwave noise and unwanted frequencies.

Abstract: Low-noise, crossed-field devices such as a microwave magnetron, a microwave oven utilizing same, crossed-field amplifier and a method of converting a noisy magnetron to a low-noise magnetron utilize an azimuthally varying, axial magnetic field. The magnetic configuration reduces and eliminates microwave and radio frequency noise. This microwave noise is present near the carrier frequency and as sidebands, far separated from the carrier. The device utilizes azimuthally varying, axial, magnetic field perturbations. In one embodiment, at least one permanent magnet is placed against the azimuthally-symmetric, axial magnetic field magnetron magnets (four magnets work especially well). This additional permanent magnet(s) causes the axial magnetic field to vary azimuthally in the magnetron and completely eliminates the microwave noise and unwanted frequencies.

Abstract: Cost-effective, simple, low-noise, crossed-field devices such as a microwave magnetron, a microwave oven utilizing same, and crossed-field amplifier utilize an azimuthally varying, axial magnetic field. The magnetic configuration reduces and eliminates microwave and radio frequency noise. This microwave noise is present near the carrier frequency and as sidebands, far separated from the carrier. The device utilizes azimuthally-varying, axial, magnetic field perturbations. At least one permanent perturbing magnet having an azimuthally-varying magnetic field impressed thereupon causes the axial magnetic field to vary azimuthally in the magnetron and completely eliminates the microwave noise and unwanted frequencies. Preferably, the number of axial magnetic field perturbations is based on the number of cavities of the magnetron.

Abstract: Method and apparatus for accelerating charged particles in a compact two-beam accelerator including a high voltage diode which generates an annular intense electron beam and a pencil-shaped secondary beam. The annular beam is modulated and functions as a driver beam for the secondary beam. A focusing magnetic field created by external focusing magnetic field coils adjusts the radius of the annular beam within a plurality of resonant cavity structures of an accelerating portion of the accelerator such that the phase slippage of the secondary beam, with reference to the co-propagated driver beam, is corrected. Correction of the phase slippage results in a secondary beam that is continuously accelerated. The external magnetic field also controls the energy of the secondary beam. Such high energy charged particles are useful in a wide variety of applications, such as medical radiation therapy, sterilization of medical equipment, industrial materials processing, inspection and industrial ion implantation.

Abstract: A klystron amplifier in which the drift tube is in the form of a casing and a central member disposed coaxially about the same centerline to form a coaxial space between the central member and the casing which runs parallel to the centerline, and through which the klystron's electron beam flows. The casing and central member are maintained at ground potential, which maintains the space charge of the electron beam at a low level, permitting the klystron to operate more efficiently and output higher power.

Abstract: A collective interactive klystron that utilizes a bent drift tube to achi circular motions of the electrons in the drift region. This bent drift tube eliminates material repulsion between AC space charges in a klystron.

Abstract: A wide-band distributed coupler for coupling rf energy from an input waveguide into a tapered interaction waveguide in a traveling-wave amplifier comprising a plurality of channel filters connecting between the input and interaction waveguides, with each filter coupled to the interaction waveguide at the appropriate cross-sectional position along its tapered length where the interaction waveguide cutoff frequency approximately matches the wave frequency propagated by the filter. Each filter comprises, in one embodiment, a main coaxial cavity tuned to a distinct center frequency, a first simple isolation cavity for coupling rf energy between the input waveguide and the main cavity, and at least one second simple isolation cavity for coupling energy between the main cavity and the tapered interaction waveguide. This coupler is compatible both in bandwidth and geometry with the tapered interaction waveguide.

Abstract: An RF cyclotron maser type traveling-wave amplifier including an integral active circulator. The amplifier includes a tapered interaction waveguide having a cross-section which gradually increases from a small first end to a larger second end thereof. The waveguide is capable of supporting first and second orthogonal polarization modes therein with approximately the same propagation characteristics for the two modes. A beam of mildly relativistic electrons having helical electron motion is directed into the small first end to axially propagate within the waveguide toward the larger second end. A tapered magnetic field is generated within the waveguide in a direction approximately parallel to the axis of the waveguide. The magnetic field is profiled to near grazing interaction with the second polarization mode of the waveguide. An input electromagnetic wave in the first polarization mode is launched into the larger second end of the waveguide to propagate toward the first end thereof.

Abstract: A gyromagnetron amplifier for radiation at millimeter wavelengths comprising a tapered waveguide tube with longitudinally running vanes in the walls of the tube with the number of vanes chosen to coincide with a desired cyclotron harmonic frequency to be amplified. A beam of spiralling mildly relativistic electrons with an energy of 100 keV or less is directed into the small end of the tapered waveguide tube. A tapered axial magnetic field is set up within the waveguide tube with a low value appropriate to the amplification of a cyclotron harmonic frequency. An electromagnetic wave to be amplified is launched into the waveguide tube to co-propagate and be amplified by the spiralling electron beam. This device is characterized by a wide bandwidth, a low operating magnetic field, a relatively low operating beam voltage, with high power, and the capability of continuous wave operation.

Abstract: A high power amplifier for amplifying millimeter-wave radiation comprising: a length of metallic waveguide tapered from a small cross-sectional end to a larger cross-sectional end; a magnetron-type electron injection gun for injecting a spiral beam of relativistic electrons at the small end of the waveguide for propagation axially therein so that the wall radius of the tapered waveguide increases in the downstream direction of the electron beam; an input coupler for launching electromagnetic waves to be amplified into the waveguide at the large waveguide end thereof such that the individual frequencies in the input waves are reflected at various points along the constriction of the waveguide taper so that they copropagate with and are amplified by the electron beam; and a magnetic circuit for generating an axial magnetic field within the tapered waveguide with a unique profile approximately in accordance with the following equation to maintain synchronism: ##EQU1## where the z subscript is the waveguide axial