Abstract: A method andan apparatus for producing a photopumped VUV laser in an Mo.sup.6+ ion-containing plasma comprise photopumping the Mo.sup.6+ ion-containing plasma with radiation from Mo.sup.11+ ions. In one embodiment, the Mo.sup.6+ ion-containing plasma has an electron density of less than about 10.sup.18 cm.sup.-3 and the Mo.sup.11+ ions are contained in a plasma having an electron density greater than about 10.sup.20 cm.sup.-3.

Abstract: The generation of soft x-ray and/or extreme untraviolet laser radiation is accomplished in a capillary plasma generated by a fast discharge. The method yields laser action at short wavelengths in a discharge created plasma having a large length-to-diameter ratio.

Abstract: A method and apparatus for sensing the wavelength of a laser beam using an optogalvano effect by atoms or molecules in plasma. Atoms or molecules in the plasma are irradiated with the laser beam. The impedance of the plasma at that time is sensed to sense whether the wavelength of the laser beam coincides with a predetermined absolute wavelength. The sensed result is used to control the wavelength of the laser beam.

Abstract: The invention relates to a plasma apparatus where plasma is generated utilizing microwave discharge and laser excitation is performed and plasma processing is performed. More specifically, in a plasma apparatus where a microwave from a microwave oscillator is transmitted through a microwave transmission path to a microwave circuit, and plasma is generated by a microwave discharge within the microwave circuit, a plasma generating medium for generating the plasma is filled in a space formed between a conductor wall constituting a part of the microwave circuit and a dielectric installed opposite to the conductor wall, and the microwave circuit forms microwave mode having an electric field component orthogonal to the boundary between the dielectric and the plasma.

Abstract: A plasma pinch system includes a fluid-jet pinch device for establishing a plasma source composed of a tenuous vapor preconditioning cloud surrounding a central narrow flowing fine stream of fluid under pressure. A discharge device is connected electrically to the fluid-jet pinch device for supplying an electrical flow through a portion of the fluid stream for establishing an incoherent light emitting plasma therealong. A method of using the plamsa pinch system for manufacturing semiconductors, includes exposing a semiconductor wafer to the incoherent light emitted by the plasma for either annealing or etching purposes.

Abstract: A traveling-wave, laser-produced-plasma, energy source used to obtain single-pass gain saturation of a photoionization pumped laser. A cylindrical lens is used to focus a pump laser beam to a long line on a target. Grooves are cut in the target to present a surface near normal to the incident beam and to reduce the area, and hence increase the intensity and efficiency, of plasma formation.

Abstract: A medium for a gas laser excited by ionizing particles containing helium, neon, argon or krypton with a total concentration in excess of 10.sup.19 cm.sup.-3 with argon or krypton concentration ranging from 3.multidot.10.sup.16 cm.sup.-3 to a value amounting to 15% of the total concentration. The medium additionally comprises at least one more component selected from the group comprising, xenon, hydrogen, hydrogen isotope, or a mixture of these components in various combinations, the concentration of each component or the mixture thereof being selected from a range from 10.sup.15 cm.sup.-3 to a value equal to 20% of the concentration of argon or krypton.

Abstract: In a gas ion laser of the type having a serial array of coaxially aligned axially spaced floating electrodes contained within an evacuable dielectric envelope for exciting a d.c. plasma laser pumping discharge, the electrodes and gas fill are cooled by a plurality of axially directed coolant tubes within the gas-filled envelope. The electrodes have a spherically shaped funnel portion immediately surrounding the laser beam and plasma discharge path for focusing secondary electrons back into the beam path for increasing conversion efficiency. The spherically shaped surfaces are electroplated with a tungsten-cobalt alloy to decrease sputter erosion.

Abstract: A method for recycling laser flashlamp radiation in selected wavelength ranges to decrease thermal loading of the solid state laser matrix while substantially maintaining the pumping efficiency of the flashlamp.

Abstract: An enhancement of approximately 100 of stimulated emission over spontaneous emission of the CVI 182 Angstrom line was obtained in a recombining magnetically confined plasma column. The plasma was formed by focusing a CO.sub.2 laser beam on a carbon disc. A magnetic solenoid produced a strong magnetic field which confined the plasma to the shape of a column. A single thin carbon blade extended parallel to the plasma column and served to make the column axially more uniform and also acted as a heat sink. Axial and transverse measurements of the soft X-ray lasing action were made from locations off-set from the central axis of the plasma column. Multiple carbon blades located at equal intervals around the plasma column were also found to produce acceptable results. According to another embodiment 10 a thin coating of aluminum or magnesium was placed on the carbon disc and blade. The Z of the coating should preferably be at least 5 greater than the Z of the target.

Abstract: A gas ion laser employs a direct current electron beam to create a rare gas ion density and a cylindrical magnetron to sputter a partial pressure of metal vapor density and to also create a rare gas ion density. Thermal energy charge transfer selectively pumps the upper metal ion laser transitions on a continuous wave basis.

Abstract: A single unitary structure for an ion laser in which the plasma tube with a surrounding electromagnet is integrated with the laser resonator tube. Cooling channels are formed by a pair of annular channels between the resonator tube, electromagnet and plasma tube. A helical, flow path in the annular channels provides uniform cooling around the resonator tube.

Abstract: Soft X-ray lasing action may be obtained by focusing a high power, picosecond laser pulse on a confined plasma column. The plasma column is created by focusing a CO.sub.2 laser pulse on a target such as carbon. A strong cylindrical magnetic field contains the plasma and causes it to assume the shape of a column. While the plasma column is cooling rapidly due to radiation losses, a second high power laser with a duration time of approximately 1 picosecond is focused along the central part of the plasma column. The powerful picosecond laser provides strong selective excitation of the ions for enhancement population inversion and the creation of high gain for X-ray lasing action. According to alternative embodiments, other multi-Z elements such as molybdenum, aluminum and krypton can be used to create a lasing medium in the plasma column.

Abstract: A highly efficient laser employs a glow discharge electron gun and includes a solid wall cathode that emits a beam of electrons resulting in a plasma that is a negative glow discharge having an electron distribution that has a larger number of high energy electrons than would be present in a Maxwellian distribution of the same electron density.

Abstract: A plasma is induced in a transmissive medium, and causes a chirp to be impressed on an optical pulse. The chirped pulse when passed through a dispersing means is then compressed. Applications of this pulse compression technique include the generation of short pulses of infrared at high power levels. Picosecond pulses of 10 micron energy are generated by switching a 2 picosecond portion from the output of a multi-atmosphere laser oscillator, and amplifying the portion in a CO.sub.2 gain module operated at gain saturation to cause a plasma front to propagate with the portion being amplified. A blue chirp of the pulse results. The pulse is passed through a dispersive medium, and a substantial decrease in pulse width and increase in energy density occurs during successive passes of the pulse through the gain module. Pulses as short as 500 femtoseconds have been produced at power densities of the order of 10.sup.12 watts/cm.sup.2. A TE/CO.sub.

Abstract: Described is a high gain, soft X-ray pumped, inner-shell, photoionization amplifier/laser in Cd or Zn vapors. The soft X-ray photoionization, generated by a laser-produced plasma or other high intensity X-ray source, preferentially removes inner-shell d-electrons from neutral atoms leaving them ionized in a .sup.2 D state and producing a population inversion with respect to a lower lying .sup.2 p state. Also described are techniques for achieving inversions with respect to the ion ground state of Cd, Zn or Hg by optically pumping from the inner-shell ionized state to a higher energy level. Iso-electronic scaling of Cd, Zn and Hg suggests similar lasing phenomena exist, for example, in Ga, In and Tl ions, respectively, and also higher iso-electronic sequences.

Abstract: A short wavelength laser (28) is provided that is driven by conventional-laser pulses (30, 31). A multiplicity of panels (32), mounted on substrates (34), are supported in two separated and alternately staggered facing and parallel arrays disposed along an approximately linear path (42). When the panels (32) are illuminated by the conventional-laser pulses (30, 31), single pass EUV or soft x-ray laser pulses (44, 46) are produced.

Abstract: A laser-pumped laser system is disclosed, such as a dye laser which is optically pumped by an argon ion laser. An improved servo system is provided for maintaining relative alignment of the pump laser beam with respect to the dye laser cavity. This is accomplished by rotating the pump beam such that the beam defines a conical surface, by means such as an optically-transmissive rotating wedge. Such rotation provides dithering along two orthogonal axes, which provides the necessary control information to maintain pump beam alignment.

Abstract: In an arc discharge device, a thin film bridges the gap(s) between adjacent electrodes, thereby enabling the arc discharge to be initiated and sustained by a low voltage D.C. supply. Application of the invention to both light source (e.g., laser) and material working (e.g., metal deposition) embodiments is described. One of the light source embodiments utilizes a cathode electrode which includes a pool of liquid Hg to generate a Hg ion plasma.

Abstract: The invention provides a laser arrangement including in its discharge circuit a switching thyratron which is capable of conduction normally in one direction and protectively in the reverse direction. The thyratron has an anode formed as a hollow body which is adapted to retain plasma generated during a pulse of forward conduction so that the anode is provided to act as a cathode permitting protective reversal of the thyratron when this is subject to reversal of voltage.

Abstract: Continuous wave laser oscillation has been achieved in a segmented plasma excitation and recombination device in the presence of a low-pressure background gas which rapidly flows across the segmented electrodes. Laser action has been observed in Cd I at 1.40, 1.43, 1.44, and 1.64 .mu.m. Also disclosed are techniques for allowing the background gas to flow between the electrodes and for confining the expanding plasmas with shields in the vicinity of the gaps between electrodes.

Abstract: A preconditioning beam is used to excite gas particles preferentially along a channel between two electrodes in a laser chamber. The preconditioning beam may be an electron beam or a laser beam. An electrical discharge between the electrodes is conducted along the channel by the excited gas particles to form a gas embedded plasma pinch. Depending on the profile of the discharge, the pinch may be stable or collapsing. The pinch emits vacuum ultraviolet radiation which photodissociates molecules of the photolytic laser medium confined by the chamber. The dissociation creates a population inversion, initiating lasing activity. A resonator system reflects the developing laser pulse back and forth through the chamber to stimulate further emissions and facilitate pulse amplification. The developed pulse is transmitted by appropriate means.

Abstract: Numerous laser transitions in the visible and near-infrared in four metal vapors (Li, Al, Ca, and Cu) have been observed in the recombination phase of the expanding plasmas produced by a segmented plasma device employing foil electrodes. Also described is a segmented vapor plasma discharge in using Ni foil electrodes.

Abstract: An electrical signal, such as a high current pulse, is applied to a series of two or more conducting strips (101-110) installed in series in a laser cavity (150, 151) containing either a buffer gas or a vacuum. The strips are separated by small gaps. When the electrical signal is applied to the strips, plasmas (141-149) are formed in the gap regions. The plasmas are comprised of ions from the strip material. Once formed, these plasmas expand hemispherically, cool and recombine to generate radiation. The composition of the plasmas depends on the strip material, the electric field in the gaps, the gap size and the background gas type and pressure.

Abstract: The present invention comprises an apparatus which provides a combination of excitation pulses or a signle shaped excitation pulse to a plasma-recombination laser which both creates the plasma and controls the electron-ion collisional recombination rate therein. The application of the single shaped excitation pulse or combination of excitation pulses keeps the electron temperature of the plasma at a temperature unfavorable to recombination until the electron density has fallen into the optimum range for laser action. The termination of the excitation pulse or pulses results in immediate laser action having power at least several orders of magnitude over that achieved in the prior art.

Abstract: An efficient recombination laser comprises a resonant laser cavity, a gaseous laser material disposed in the cavity, and means for providing a plasma discharge in said laser material, which plasma discharge is confined to a cylindrical region along the axis of the laser cavity. The plasma in the gaseous laser material expands outward radially from the cylindrical region at the axis of the cavity and cools by interacting with the adjacent unexcited gas. The maximum laser gain is provided in an annular region, which annular region is adjacent to and surrounds the initial discharge cylindrical region. In one embodiment of the present invention, the means for providing the plasma discharge comprises two pin-type electrodes which extend into the cavity along the cavity axis.

Abstract: A high-voltage, high current pulse is applied to a series of two or more conducting strips (101-110) installed in series in a laser cavity (150-151) containing either a buffer gas or a vacuum. The strips are separated by small gaps. When the high-voltage, high-current pulse is applied to the strips, plasmas (141-149) are formed in the gap regions. The plasmas are comprised of ions from the strip material. Once formed, these plasmas expand hemispherically, cool and recombine to provide laser action. The composition of the plasmas depends on the strip material, the electric field in the gaps, the gap size and the background gas type and pressure.

Abstract: The present invention relates to a system for generating extreme ultraviolet (XUV) radiation. The process utilizes pulsed plasmas to create a high density of ions in which non-linear frequency upconversion into the XUV region can occur. In particular, metals are utilized as the lasing medium in the present invention, since the ions of these metals do not absorb wavelengths in the XUV region and a significant level of XUV output may be obtained. Conventional UV lasers are utilized as the upconverters for the ionized metals.