Abstract: An actively Q-switched laser induced breakdown spectroscopy (LIBS) probe, utilizing an optical fiber, a pump beam transmitted through the optical fiber, a coupler, and a lens for collimating the pump beam. The actively Q-switched laser, coupled to a sensor which provides information to a computer that controls a high voltage pulser providing a pulse to a Pockels cell located within the laser which can selectively cause the laser to pulse, resulting in high energy pulses and a second lens for focusing the output pulse such that it creates a plasma or spark. The light from the spark is captured and directed back through an optical system to remote equipment for elemental and/or molecular analysis.

Abstract: A free electron laser FEL comprises an undulator 24 generating coherent EUV radiation receiving an upstream electron beam EB2 and emitting a downstream electron beam EB4 and at least an electron source 21a, 21b operable to produce an upstream electron beam EB1, EB2 comprising bunches of electrons. A beam path is configured to direct the upstream electron beam through: a linear accelerator system (LINAC) comprising at least a first and a second linear accelerators 22a, 22b, a bunch compressor 28b, and said undulator 24.

Abstract: A technique for controlling and compensating the energy spread of a charged particle beam is provided. This technique is based on a passive dielectric-loaded structure that redistributes the energy within the bunch by means of the wakefield generated in the structure. Cylindrical and planar structure configurations are provided and also means for electrical and mechanical tuning to optimize performance. The instant abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way.

Abstract: 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.

Abstract: A resonant apparatus such as a resonant waveguide module in an RF particle accelerator includes an unbrazed joint that provides a reliable vacuum seal and RF contact between resonators with precisely controlled internal geometry. The joint can be disassembled and reassembled without degradation. Hard, stainless steel end faces include knife edges pressed into a copper central component, such as a gasket. The knife edges extend the waveguide interiors without gaps or interruptions. The central component serves as a coupling iris or other functional component of the resonant apparatus, thereby allowing the central component to have substantial dimensions that inhibit mechanical distortions thereof. The waveguides and knife edges can be copper plated. Embodiments include embedded passages and/or recesses used for cooling, radiation shielding, magnetic focusing coils, and/or electron optics element formed by permanent magnets.

Abstract: A modulator includes an electro-optical substrate and a first and second waveguide formed of a doped semiconductor material positioned on a surface of an electro-optical substrate forming a slot therebetween. A doping level of the semiconductor material being chosen to make the first and second waveguide conductive. A dielectric material is positioned in the slot which increases confinement of both an optical field and an electrical field inside the slot. A refractive index of the semiconductor material and a refractive index of the dielectric material positioned in the slot being chosen to reduce the V?·L product of the modulator.

Abstract: A light generating system that comprises a narrow evacuated slot defined between at least two high index contrast waveguide elements. The apparatus can be fabricated using a material such as a SOI wafer having an oxide layer thickness of the order of 1 micron and a top silicon layer thickness of the order of 100-150 nm. Electrode contacts are provided to at least two waveguide elements fabricated in the top silicon layer, each waveguide element having a thickness comparable to the top silicon layer thickness, a width of some hundreds of nm, and having a slot having dimensions in the range of 50-200 nm defined therebetween. The length of the slot is at least as long as the slot width. Charged particles, such as electrons, that are emitted and accelerated across the slot by an applied electrical signal provide a source of photons as a consequence of being accelerated and/or decelerated.

Abstract: A method of tunable generation of terahertz radiation comprising: (A) providing a magnon gain medium; wherein the magnon gain medium supports generation of nonequilibrium magnons; (B) generating terahertz radiation in the magnon gain medium; and (C) tuning frequency of the terahertz radiation by causing changes in an external parameter. The substantial tuning of the frequency of the generated terahertz radiation can be achieved by applying an external magnetic field, and by causing changes in a value of the external magnetic field.

Abstract: The present invention provides a method for modulating light by a driven particle beam is disclosed. An optical beam is being sent to metal-dielectric structure so that the optical field partially transforms into a delayed electromagnetic wave, in a preferred embodiment into the surface evanescent mode, and the beam of charged particles, such as electrons, is also sent to said structure the way that the particle's kinetic energy partially transforms into energy of the delayed electromagnetic wave having the same phase-frequency characteristics as transformed field of optical beam at that, transformation of the optical beam and excitation of wave by particle beam commonly take place at the same small space region, which is localized by said metal-dielectric structure. Delayed electromagnetic wave, which is generated by particle beam, is summarized with the optical field, which is transformed on said structure.

Abstract: A tunable multimode wavelength division multiplex Raman pump and amplifier, and a system, method, and computer program product for controlling a tunable Raman pump and amplifier. The tunability of the pump source is accomplished by either straining or heating an external fiber grating, thereby causing a different wavelength of light to be emitted by the pump source. The system includes a microprocessor-based controller that monitors an amplifier's performance and adjusts the drive current and/or wavelength of the tunable pumps of an amplifier to achieve a target performance.

Abstract: The present invention provides a method for manufacturing an optical element to be used for an optical system and an optical instrument using the optical system, and a method for manufacturing a device using the optical instrument, wherein the optical element is manufactured by the steps including the steps for processing a high purity silica glass by lithography, and the hydrogen molecule content is adjusted after manufacturing the optical element.

Abstract: A communications system that includes one or more free space electron switches. The free space electron switch employs an array of electron emitters, where each emitter is responsive to an RF or optical input signal on an input channel. Each emitter includes a cathode that emits electrons in response to the input signal. Each emitter further includes a focussing/accelerating electrode for collecting and accelerating the emitted electrons into an electron beam. Each emitter further includes an aiming anode that directs the beam of electrons to a desired detector within an array of detectors that converts the beam of electrons to a representative RF or optical signal on an output channel. Each emitter may include a modulating electrode that generates an electric field to modulate data onto the beam of electrons. The communications systems employing the switch can be an ISDN, DSLAM networks, packet routing systems, ADSL networks, PBX systems, local exchange systems, etc.

Abstract: Within a vacuum vessel, there are arranged an electron emitting part emitting an electron beam in a first direction, and an optical amplifying part amplifying incident light with the help of energy of the electron beam. The optical amplifying part includes a flat dielectric substrate made of a quartz glass, a rectilinear dielectric optical waveguide provided on the flat dielectric substrate, made of a dielectric material having a high refractive index and extending in said first direction, input and output optical waveguides provided on the dielectric substrate and being coupled with both ends of the dielectric optical waveguide, and a pair of electron beam converging electrodes arranged on respective sides of the dielectric optical waveguide. A velocity of the incident light is delayed during propagation through the dielectric optical waveguide, and a part of the incident light penetrates from the dielectric optical waveguide into the vacuum in the form of evanescent light.

Abstract: An ignition feedback regenerative amplifier consists of an injector, a linear accelerator with energy recovery, and a high-gain free electron laser amplifier. A fraction of the free electron laser output is coupled to the input to operate the free electron laser in the regenerative mode. A mode filter in this loop prevents run away instability. Another fraction of the output, after suitable frequency up conversion, is used to drive the photocathode. An external laser is provided to start up both the amplifier and the injector, thus igniting the system.

Abstract: A system and method for modification of tissue. The system and method utilize a disposable sample cell that contains a chemical mixture capable of photoinitiation. Upon photoinitiation, a chemical reaction creates electromagnetic radiation that is readily absorbed by a desired portion of tissue. The absorption of energy creates heat which can be controlled to result in predetermined modifications to the tissue.

Abstract: A unidirectional optical amplifier comprising an optical dielectric waveguide having a high refraction index for leading light from a light input terminal to a light output terminal and a straight electron beam transit section extended in an electron beam transit direction. The optical amplifier includes an amplifier section for amplifying light in one direction by utilizing an energy level sufficiently higher than a Fermi level, and an emissive section for emitting an electron beam in the electron beam transit section. The electron beam transit section is preferably constituted so that the effective mass of an electron in the amplifier section becomes small, and the optical dielectric waveguide and the electron beam transit section are arranged in such a manner that the wave number of light in the amplifier section becomes large and an electric field component of the light is generated in the electron beam transit direction.

Abstract: Within a vacuum vessel 10, there are arranged an electron gun 2 emitting an electron beam and an amplification part 3 which amplifies incident light 7 by means of the energy of the electron beam. The amplification part 3 is formed by two wave-like mirrors 4 and 5 made of a metal such as Ag or a multi-layer structure of dielectric materials, said mirrors being separated from each other to constitute not only an electron beam travelling part, but also a light input part 4a, 5a, a light amplifying part 4b, 5b and a light output part 4c, 5c arranged in this order viewed in a travelling direction of the electron beam. The light is made incident upon the light input part at a given incident angle, and propagates along the wave-like or zigzag optical waveguide within the light amplifying part by repeating reflections. Therefore, the wavenumber of the light is increased, and the light is amplified in a unidirectional manner by the energy of the electron beam.

Abstract: An infrared lens assembly may comprise a lens set (32) including one or more refractive lenses. The refractive lens may be positioned along an optic axis (30) to receive infrared radiation. The lens set (32) may be designed to focus infrared radiation of a scene (14) at an image plane (15). An athermalization element (34) may be positioned along the optic axis (30) in optical communication with the lens set (32). The athermalization element (34) may include an infrared transmitting member (40) supporting a diffractive pattern (42). The infrared transmitting member (40) may comprise an infrared transmitting polymer. The diffractive pattern (42) may compensate for temperature induced changes in a focal length of the lens set (32) to maintain infrared radiation of the scene (14) in focus at the image plane (15).

Abstract: A system for a video cassette recorder is capable of recording/reproducing analog video and audio signals as well as digital video and audio signals for a HDTV.The revolution of a head drum may be determined different from each other depending on the selected mode, i.e., digital or analog signal recording/reproducing mode, and thus the digital signal having a different recording bandwidth from the analog signal can be recorded on and reproduced from a conventional analog tape.