Abstract: A method and system for extraction of visible optical energy from gas lasers having simultaneous ultraviolet and visible transitions. In this disclosed method, stimulated emission on the UV transition of rare-gas halide molecules is converted to a wavelength which coincides with the wavelength of the visible transition using a dye laser cell mounted in a common optical cavity with the visible laser. Excitation of the rare-gas halide laser produces high gain UV and low gain visible transitions. The UV is focused into a visible dye cell, and stimulated emission occurs in the dye cell which is contained in an optical cavity also containing the gas laser. The stimulated emission of the dye cell is amplified by the discharge-pumped gas laser medium. Since the gain of the dye laser is very high, the arrangement allows laser emission at the visible wavelength to build-up very rapidly during the gas laser excitation discharge pulse. Laser emission has been produced over a waveguide bandwidth between 460 and 510 nm.

Abstract: An adjustable linear integrating mirror for producing spatially uniform b areas of high power lasers. The mirror is formed by a plurality of thin solid rectangular blocks made of a highly reflective metal with one thin face ground to a flat mirror finish. The blocks are assembled one upon the other with their mirror faces in alignment and held together at their ends by strips of spring steel. Wedge-shaped spacers are inserted between their free ends opposite the mirrored face to produce small angular rotations of each mirrored block. The spring steel should have sufficient tension to secure the wedges in place; however, if necessary, clamps may be used to hold the back ends together to secure the wedges in place. The angular setting of the mirrored blocks will determine the amount of overlay of the reflected laser beam. Fine tuning for a specific overlay may be performed by varying the depth of the wedges which varies the angular setting of each mirrored block section.

Abstract: A three-dimensional bootlace lens with minimum possible focusing aberrati, minimum possible focusing size and minimum possible dielectric loading. The feed and lens surfaces are in the shape of a spherical cap and covered by contiguous arrays of radiators. The region between the inner surfaces of the lens is filled with a nonuniform dielectric material with an index of refraction which constantly changes from the center line outwardly. Lens ports are connected to a radiating antenna array by means of coaxial transmission lines all of which have the same length. The axial feed point has a focusing performance which is perfect. For all other points the lens is free of all first-order aberrations except coma. The outputs of the lens can be used to feed a planar radiating antenna array so as to produce a multiple directive beam in one angular dimension or to feed a circular array so as to make it amenable to scanning or multibeam feed systems that are used with linear arrays.

Abstract: An efficient, four-level, blue-green, excimer-pumped laser which is opera at room temperature. The laser element includes a CaWO.sub.4 crystal which has been codoped with trivalent thulium activator ions and divalent ytterbium sensitizer ions. Energy is transferred from the absorbing Yb.sup.2+ ions to the Tm.sup.3+ ions and the laser transition is from the .sup.1 D.sub.2 multiplet to the ground .sup.3 F.sub.4 of the Tm.sup.3+ ion. This transition terminates on an excited state; therefore, the laser action is four-level.

Abstract: A method for protecting an ion-implanted substrate during the annealing process by covering the ion-implanted layer with a suitable encapsulant. A thin layer of ions are implanted into a GaAs substrate. A protective layer of germanium, amorphous GaAs, doped GaAs, or GaAlAs is applied over the implanted layer and on the periphery of the ion-implanted GaAs substrate. The composite is annealed at a temperature which is adequate for the lattice to recover from the ion-implantation-induced damage. The protective layer is removed subsequent to the anneal step, without any damage to the ion-implanted layer.

Abstract: A method of attaining n.sup.+ regions with fine planar geometry in the source and drain of GaAs devices utilizing ion implantation which improves Ohmic contact with a refractory film. A layer of TiW refractory film is deposited on GaAs. .sup.29 Si ions are implanted in the GaAs through the refractory film so that the peak concentration is no more than approximately 100 A below the TiW-GaAs interface. The entire structure is then annealed. A gold overlay is then deposited on the TiW layer to which electrical contacts may be attached and by which the contact resistivity is measured. Typical specific contact resistivity values are in the low 10.sup.-6 ohm/cm.sup.2 range.

Abstract: A single or multilayer optical interference filter and method of forming filter by ion implantation. One or more layers of nitrogen ions are implanted into a single crystal silicon with the crystal at a temperature of from about 600.degree. C. to about 1000.degree. C. The implanted ions create a buried layer(s) of silicon nitride (Si.sub.3 N.sub.4) whose refractive index is substantially different from that of silicon (Si) such that appreciable multiple reflection of incident light occurs between the buried layer(s) and the front surface. The resulting interference maxima and minima in transmitted or reflected light which occur at well-defined positions in wavelength may be controlled both in amplitude and wavelength position. The ions may be implanted in layers at different depths to produce a "thin film" interference filter.

Abstract: A planar, silicon barrier, Josephson junction and method of forming the jtion which does not require expensive high-resolution, lithography techniques such as electron beam or x-ray. The method includes an etching mask-etch process which forms the basic structure configuration using a (110)-cut silicon wafer. Subsequent to the etching process the mask is removed and a superconducting film is deposited on the previously formed silicon surface to produce a single crystal silicon barrier with good electrical properties.

Abstract: A multi-arrayed electron emitter for microwave tubes in which the emitting urface is an array of continually replenished low-work-function regions, (micro-patches), whose boundaries include a control grid which is integral with the cathode surface and which controls emission from the low-work-function micro-patches. The continually replenished low-work-function regions are uniformly positioned relative to a matrix of uniformly spaced openings through which the low-work-function material is released.

Abstract: An improved electron-beam-pumped and electron-beam-controlled (EBC) XeF laser in which a diluent gas of neon is used. Addition of neon allows increased optical extraction energies with improved performance which provides greater efficiency with increased optical pulse width.

Abstract: A laser system in which acetylene is mixed with a gaseous mixture of helium and carbon monoxide which has been vibrationally excited significantly populating the lower vibrational levels of the CO. The carbon monoxide will transfer its energy to the acetylene, populating the upper (01000) level to create laser radiation near 15.9 microns which may be operated in continuous-wave or pulsed modes. The laser cavity includes mirrors which are highly reflective at 16 microns but transparent to radiation at 8 microns or other well-known means which will operate in the same fashion.

Abstract: A flexible, composite, acoustical energy transducer made from ferroelectric, piezoelectric, and/or electrostrictive materials in combination with a polymer, such as silicone or polyvinylidene fluoride (PVF.sub.2), preferably having electroelastic properties. The materials are formed into platelets or wafers which have electrodes on their facial surfaces and are arranged within the polymer with each wafer in the same x-y plane such that their polarizations are in the same direction and perpendicular to the x-y plane. The wafers are aligned in directed rows, spaced from each other and are totally encased within the polymer. Thin conductive sheet or foil electrodes are secured to the upper and lower faces of the polymer and a conductive material between each wafer and the foil electrically connects the wafers to the foil electrodes. To protect the electrodes and prevent electrical shorting, a rubber coating or any other suitable insulator may be applied to the outside of the electrodes.

Abstract: Improved TRAPATT diodes in which the improvement comprises a high-temperae metallization on silicon from which the diodes are formed.Metallization is applied to a silicon wafer by sputtering a layer of titanium, chromium, tungsten alloy followed by a gold layer. The desired diode shape and size is defined in the gold layer by use of a pattern of the proper shape and size in combination with a photolithographic process. The metallization layers and the silicon are then etched so as to form a plurality of individual shaped (mesa or ring structure) TRAPATT diodes. Such diodes can withstand 610.degree. C. for one hour without degradation.

Abstract: An improved electric-discharge-excited mercury halide dissociation laser operable on the (B-X) transitions in HgCl, HgBr and HgI at 558, 502 and 443 nm respectively. The laser discharge cell is elongated and made from temperature-resistant silicon-glass laminate or any other suitable material and includes separate ceramic crucibles for containing mercuric dihalide crystals. A pair of electrodes, each having external terminals, extend along the linear axis of the cell in parallel relationship with the linear axis and each other. Ultraviolet discharge means is also provided for preionizing a buffer gas of helium to which nitrogen has been added. The improvement comprises the addition of about 10% nitrogen to the buffer gas of helium which is admitted to the laser cell prior to excitation. The addition of nitrogen may act to selectively remove the terminal levels of the mercury halide laser transitions, thereby permitting more efficient extraction of the optical energy from the laser media.

Abstract: A high-power gas laser pumped by an intense, pulsed, space charge-and current-neutralized ion beam. A high-pressure gas in the laser cavity is ionized by an ion beam. Atomic processes occur which result in a population inversion for the excited states of the gas. Coherent radiation is then emitted by the excited gas atoms in the inverted state. The light is amplified as it traverses the gas. Multiple traversal can be obtained by using an optical cavity comprising mirrors which reflect the light into the excited gas so that the light can be further amplified with each pass through the cavity. Extraction of light energy is done by using a partially transmitting mirror as part of the optical cavity.

Abstract: A method of growing high-quality, super-abrupt, thin-film epitaxial layers independent of a GaAs substrate. An elemental semiconductor of germanium is used to initiate growth of an active material, typically doped n-type. A semi-insulating layer or n+ layer is grown on the n-type active material. Subsequent to growth of the semi-insulating layer, a thin cap of germanium is deposited on the composite. Gold is deposited onto the germanium cap to form an eutectic-alloy layer with the germanium. The alloy is formed and the composite is bonded to a metal, glass, or ceramic substrate and the semiconductor (germanium) is removed by etching and the n-layer is finally etched to provide a clean-up and to tailor the layer to a desired thickness. Subsequent steps are employed to form desired structures such as field-effect transistors or Schottky-barrier devices.

Abstract: A method of introducing magneto-optic bias into a ring laser permitting its se as a gyroscope. A Kerr reflective mirror is positioned in one leg of a triangle between reflectors at two vertices so that radiation from a reflector at one of the vertices is reflected at the maximum practical angle of incidence to a reflector at the adjacent vertex. By incorporating the reflective magneto-optic element at near-grazing incidence, full advantage is taken of the dependence of the magneto-optical properties upon angle of incidence.

Abstract: A method for determining the compensation density of narrow-gap semiconductors. Photo-excited carriers are generated by uniformily irradiating a sample with a laser pulse of a particular density and pulse width for a particular time length and at a low sample temperature. The laser wavelength is chosen with a photon energy sufficiently high that carriers are excited from the conduction band by normal intrinsic absorption (one-photon absorption). Subsequent to the laser pulse, conductivity-voltage measurements are taken as a function of time during the photo-electron decay. Such measurements are made for different applied source-detector connections on the same sample with identical pulse-time values for each different correction. The sample is then laser-pulsed as before with a magnetic field normal to the sample surface to obtain Hall-voltage measurements. The measurements are averaged for the same time duration and the average of all curves are used in the determination.

Abstract: A collective particle accelerator including an intense relativistic elect beam (IREB) generator, an automodulation section, an acceleration region and injection region. A negative high voltage is applied to a ring cathode which produces an IREB. The IREB propagates through the accelerator. On propagating through the automodulation section, the electrons are modulated thereby forming them into ring-shaped bunches. The acceleration section is surrounded by a longitudinal uniform magnetic field along its length and is provided with special magnetic field means which changes the uniform magnetic field to a rippled magnetic field. The rippled magnetic field causes the bunches of electrons to contract and expand radially as they propagate through the rippled magnetic field which in turn causes ions or electrons injected into the system to be accelerated by attraction or repulsion as the electron rings contract and expand radially.

Abstract: A planar, optical star and access coupler for multiterminal communication systems which use multimode fibers as the transmission line either as a plurality of single fiber lines, in multichannel fiber cable or in minibundles. The fibers are placed in a row so that the core ends abut the end of a high-aspect angle rectangular cross section clad ribbon fiber which is preferably not as thick as the diameter of the core of the individual fibers for optimum packing fraction loss. Optical radiation, such as from a laser or light-emitting diode, entering the ribbon-fiber mixer element from all of the fibers on one end will be mixed by the ribbon fiber and be transmitted equally on each of the output fibers. Also, radiation from any one fiber will be divided equally between all of the transmission fibers on the opposite end of the ribbon fiber.