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Sample records for pumped laser systems

  1. Optically pumped isotopic ammonia laser system

    DOEpatents

    Buchwald, Melvin I.; Jones, Claude R.; Nelson, Leonard Y.

    1982-01-01

    An optically pumped isotopic ammonia laser system which is capable of producing a plurality of frequencies in the middle infrared spectral region. Two optical pumping mechanisms are disclosed, i.e., pumping on R(J) and lasing on P(J) in response to enhancement of rotational cascade lasing including stimulated Raman effects, and, pumping on R(J) and lasing on P(J+2). The disclosed apparatus for optical pumping include a hole coupled cavity and a grating coupled cavity.

  2. Design of diode laser systems for solid state laser pumping

    NASA Astrophysics Data System (ADS)

    Michel, D.; Luethy, Willy A.; Weber, Heinz P.

    2003-11-01

    In contrast to flashlamps the emission of single stripe laser diodes is highly directional and can be focused rather easily to small spots, which gives access to very high pump intensities. Numerical arrangements are possible for transferring the pump radiation to the solid state laser media. In this paper the most important concepts of diode laser systems for pumping solid state lasers are summarized and described. Thereby the aim is to find the most efficient and powerful method for endpumping a Yb3+-double clad fiber.

  3. Diode-pumped laser with improved pumping system

    DOEpatents

    Chang, Jim J.

    2004-03-09

    A laser wherein pump radiation from laser diodes is delivered to a pump chamber and into the lasing medium by quasi-three-dimensional compound parabolic concentrator light channels. The light channels have reflective side walls with a curved surface and reflective end walls with a curved surface. A flow tube between the lasing medium and the light channel has a roughened surface.

  4. A modified pump laser system to pump the titanium sapphire laser

    NASA Technical Reports Server (NTRS)

    Petway, Larry B.

    1990-01-01

    As a result of the wide tunability of the titanium sapphire laser NASA has sited it to be used to perform differential absorption lidar (DIAL) measurements of H2O vapor in the upper and lower troposphere. The titanium sapphire laser can provide a spectrally narrow (0.3 to 1.0 pm), high energy (0.5 to 1.0 J) output at 727, 762, and 940 nm which are needed in the DIAL experiments. This laser performance can be obtained by addressing the line-narrowing issues in a master oscillator and the high energy requirement in a fundamental mode oscillator. By injection seeding, the single frequency property of the master oscillator can produce a line narrow high energy power oscillator. A breadboard model of the titanium sapphire laser that will ultimately be used in NASA lidar atmospheric sensing experiment is being designed. The task was to identify and solve any problem that would arise in the actual laser system. One such problem was encountered in the pump laser system. The pump laser that is designed to pump both the master oscillator and power oscillator is a Nd:YLF laser. Nd:YLF exhibits a number of properties which renders this material an attractive option to be used in the laser system. The Nd:YLF crystal is effectively athermal; it produces essentially no thermal lensing and thermally induced birefringence is generally insignificant in comparison to the material birefringence resulting from the uniaxial crystal structure. However, in application repeated fracturing of these laser rods was experience. Because Nd:YLF rods are not commercially available at the sizes needed for this application a modified pump laser system to replace the Nd:YLF laser rod was designed to include the more durable Nd:YAG laser rods. In this design, compensation for the thermal lensing effect that is introduced because of the Nd:YAG laser rods is included.

  5. Green pumped Alexandrite lasers

    NASA Astrophysics Data System (ADS)

    Kuper, Jerry W.; Brown, David C.

    2005-04-01

    Initial experiments with pulsed and CW pumping an alexandrite laser rod at 532 nm are presented. This pumping architecture holds promise for the production of scalable diode-pumped, tunable alexandrite laser systems operating in the near infrared (750 nm), and the ultraviolet (375 and 250 nm) spectral regions.

  6. Method and system for homogenizing diode laser pump arrays

    DOEpatents

    Bayramian, Andy J

    2013-10-01

    An optical amplifier system includes a diode pump array including a plurality of semiconductor diode laser bars disposed in an array configuration and characterized by a periodic distance between adjacent semiconductor diode laser bars. The periodic distance is measured in a first direction perpendicular to each of the plurality of semiconductor diode laser bars. The diode pump array provides a pump output propagating along an optical path and characterized by a first intensity profile measured as a function of the first direction and having a variation greater than 10%. The optical amplifier system also includes a diffractive optic disposed along the optical path. The diffractive optic includes a photo-thermo-refractive glass member. The optical amplifier system further includes an amplifier slab having an input face and position along the optical path and separated from the diffractive optic by a predetermined distance. A second intensity profile measured at the input face of the amplifier slab as a function of the first direction has a variation less than 10%.

  7. Method and system for homogenizing diode laser pump arrays

    DOEpatents

    Bayramian, Andrew James

    2016-05-03

    An optical amplifier system includes a diode pump array including a plurality of semiconductor diode laser bars disposed in an array configuration and characterized by a periodic distance between adjacent semiconductor diode laser bars. The periodic distance is measured in a first direction perpendicular to each of the plurality of semiconductor diode laser bars. The diode pump array provides a pump output propagating along an optical path and characterized by a first intensity profile measured as a function of the first direction and having a variation greater than 10%. The optical amplifier system also includes a diffractive optic disposed along the optical path. The diffractive optic includes a photo-thermo-refractive glass member. The optical amplifier system further includes an amplifier slab having an input face and position along the optical path and separated from the diffractive optic by a predetermined distance. A second intensity profile measured at the input face of the amplifier slab as a function of the first direction has a variation less than 10%.

  8. Diode-laser-pumped Nd:YAG laser injection seeding system

    SciTech Connect

    Schmitt, R.L.; Rahn, L.A.

    1986-03-01

    We have designed and tested a compact injection seeding system consisting of a diode-laser-pumped Nd:YAG master oscillator and a permanent-magnet Faraday isolator. With active resonator frequency stabilization, this system permits highly reliable single-axial-mode operation of a Q-switched Nd:YAG laser over a period of hours. The system is capable of injection seeding both stable and unstable resonator designs and is suitable for injection seeding commercial lasers with only minor modifications.

  9. Laser demonstration and performance characterization of optically pumped Alkali Laser systems

    NASA Astrophysics Data System (ADS)

    Sulham, Clifford V.

    Diode Pumped Alkali Lasers (DPALs) offer a promising approach for high power lasers in military applications that will not suffer from the long logistical trails of chemical lasers or the thermal management issues of diode pumped solid state lasers. This research focuses on characterizing a DPAL-type system to gain a better understanding of using this type of laser as a directed energy weapon. A rubidium laser operating at 795 nm is optically pumped by a pulsed titanium sapphire laser to investigate the dynamics of DPALs at pump intensities between 1.3 and 45 kW/cm2. Linear scaling as high as 32 times threshold is observed, with no evidence of second order kinetics. Comparison of laser characteristics with a quasi-two level analytic model suggests performance near the ideal steady-state limit, disregarding the mode mis-match. Additionally, the peak power scales linearly as high as 1 kW, suggesting aperture scaling to a few cm2 is sufficient to achieve tactical level laser powers. The temporal dynamics of the 100 ns pump and rubidium laser pulses are presented, and the continually evolving laser efficiency provides insight into the bottlenecking of the rubidium atoms in the 2P3/2 state. Lastly, multiple excited states of rubidium and cesium were accessed through two photon absorption in the red, yielding a blue and an IR photon through amplified stimulated emission. Threshold is modest at 0.3 mJ/pulse, and slope efficiencies increase dramatically with alkali concentrations and peak at 0.4%, with considerable opportunity for improvement. This versatile system might find applications for IR countermeasures or underwater communications.

  10. Diode-laser-pumped Nd:YAG laser injection seeding system.

    PubMed

    Schmitt, R L; Rahn, L A

    1986-03-01

    We have designed and tested a compact injection seeding system consisting of a diode-laser-pumped Nd:YAG master oscillator and a permanent-magnet Faraday isolator. With active resonator frequency stabilization, this system permits highly reliable single-axial-mode operation of a Q-switched Nd:YAG laser over a period of hours. The system is capable of injection seeding both stable and unstable resonator designs and is suitable for injection seeding commercial lasers with only minor modifications. PMID:18231224

  11. Optically pumped planar waveguide lasers: Part II: Gain media, laser systems, and applications

    NASA Astrophysics Data System (ADS)

    Grivas, Christos

    2016-01-01

    The field of optically pumped planar waveguide lasers has seen a rapid development over the last two decades driven by the requirements of a range of applications. This sustained research effort has led to the demonstration of a large variety of miniature highly efficient laser sources by combining different gain media and resonator geometries. One of the most attractive features of waveguide lasers is the broad range of regimes that they can operate, spanning from continuous wave and single frequency through to the generation of femtosecond pulses. Furthermore, their technology has experienced considerable advances to provide increased output power levels, deriving benefits from the relative immunity from the heat generated in the gain medium during laser operation and the use of cladding-pumped architectures. This second part of the review on optically pumped planar waveguide lasers provides a snapshot of the state-of-the-art research in this field in terms of gain materials, laser system designs, and as well as a perspective on the status of their application as real devices in various research areas.

  12. Diode-pumped laser research

    NASA Technical Reports Server (NTRS)

    Ramos-Izquierdo, L.; Bufton, J. L.; Chan, K.

    1988-01-01

    The Laboratory for Oceans is currently working on the development of compact laser diode array (LD) pumped Nd:YAG lasers for use in space-based altimetry and ranging. Laser diode-array pumping technology promises to increase the electrical to optical efficiency of solid state lasers by an order of magnitude with a lifetime increase of nearly three orders of magnitude relative to today's conventional flashlamp-pumped laser systems. The small size, efficiency, and ruggedness make LD-pumped solid state lasers ideal for space based applications. In an in-house RTOP effort, a novel multiple-pass LD-pumped Nd:YAG laser amplifier was designed and tested to increase the 100 microjoule output pulse energy of the Lightwave laser oscillator. Preliminary results have yielded a round trip amplifier gain of about 15 percent using 7 microjoule LD-pump energy. As a parallel activity, funding was recently obtained to investigate the possible use of custom made fiber optic arrays to obtain an efficient optical coupling mechanism between the emitting laser diode-arrays and the target solid state laser material. Fiber optic coupling arrays would allow for the easy manipulation of the spatial emitting pattern of the diode pump sources to match either an end or side pumping laser configuration.

  13. All solid-state picosecond flashlamp pumped oscillator-amplifier Nd:YAG laser system

    NASA Astrophysics Data System (ADS)

    Jelinkova, Helena; Cech, Miroslav; Kubecek, Vaclav; Dombrovsky, Andrej; Diels, Jean-Claude M.; Stintz, Andreas

    2005-03-01

    Flashlamp pumped oscillator - three amplifiers Nd:YAG picosecond laser system mode-locked with multiple quantum well (MQW) saturable absorber was developed and investigated. 80 ps long pulses with the energy of 120 mJ were generated.

  14. CW laser pumped emerald laser

    SciTech Connect

    Shand, M.L.; Lai, S.T.

    1984-02-01

    A CW laser-pumped emerald laser is reported. A 34 percent output power slope efficiency is observed with longitudinal pumping by a krypton laser in a nearly concentric cavity. The laser has been tuned from 728.8 to 809.0 nm. Losses in emerald are larger than those of alexandrite determined in a similar cavity. The present data also indicate that the excited state absorption minimum is shifted from that of alexandrite. 13 references.

  15. Direct nuclear pumped laser

    DOEpatents

    Miley, George H.; Wells, William E.; DeYoung, Russell J.

    1978-01-01

    There is provided a direct nuclear pumped gas laser in which the lasing mechanism is collisional radiated recombination of ions. The gas laser active medium is a mixture of the gases, with one example being neon and nitrogen.

  16. Laser emission of Rhodamine 110--coumarin bifluorophoric systems under coaxial flashlamp pumping

    SciTech Connect

    Geng Zhang, F.; Lian Yu, C.

    1987-07-01

    In this paper the experimental results of the laser emission of Rhodamine 110--coumarin bifluorophoric systems under coaxial flashlamp pumping have been reported. When coumarin 7 is used as a sensitizer, the laser output of Rhodamine 110 is increased by 130% over that without a sensitizer.

  17. SOLAR PUMPED LASER MICROTHRUSTER

    SciTech Connect

    Rubenchik, A M; Beach, R; Dawson, J; Siders, C W

    2010-02-05

    The development of microsatellites requires the development of engines to modify their orbit. It is natural to use solar energy to drive such engines. For an unlimited energy source the optimal thruster must use a minimal amount of expendable material to minimize launch costs. This requires the ejected material to have the maximal velocity and, hence, the ejected atoms must be as light as possible and be ejected by as high an energy density source as possible. Such a propulsion can be induced by pulses from an ultra-short laser. The ultra-short laser provides the high-energy concentration and high-ejected velocity. We suggest a microthruster system comprised of an inflatable solar concentrator, a solar panel, and a diode-pumped fiber laser. We will describe the system design and give weight estimates.

  18. DPSSL pumped 20-TW Ti:sapphire laser system for DD fusion experiment

    NASA Astrophysics Data System (ADS)

    Sekine, T.; Hatano, Y.; Takeuchi, Y.; Kawashima, T.

    2016-03-01

    A diode-pumped solid-state laser (DPSSL) pumped 20-TW output Ti:sapphire laser system has been developed. A diode-pumped Nd:glass laser with output energy of 12.7 J in 527 nm was used as a pump source for a 20-TW Ti:sapphire amplifier. A CeLiB6O10 nonlinear optical crystal was used as a frequency doubler of the Nd:glass DPSSL[1]. Figure 1 shows typical output pulse energy of the 20-TW amplifier as a function of pumping energy and a near field pattern. A 1.65 J pulse energy was obtained by 4.5 J pump energy. The amplified seed pulse is compressed to typically 60 fs as shown in Fig. 1 by a vacuumed pulse compressor with 80% of transmissivity. Encircled energy ratio, into a circled with 8 μm diameter area, of far field pattern focused by off-axis parabolic mirror with F# of 3 is numerically evaluated to 40% at TW class output condition. Then focal intensity would reach to 1018W/cm2. This all- DPSSL system contributes for stable and continual investigation of laser induced plasma experiment. We have succeeded continual and high efficient generation of DD fusion neutron from CD nano-particles by cluster fusion scheme using the 20-TW laser. A yield of ∼105 neutrons per shot was stably observed during continuous 100 shots with repetition rate of 0.1Hz.

  19. Pharyngeal pumping continues after laser killing of the pharyngeal nervous system of C. elegans

    SciTech Connect

    Avery, L.; Horvitz, H.R. )

    1989-10-01

    Using a laser microbeam to kill specific subsets of the pharyngeal nervous system of C. elegans, we found that feeding was accomplished by two separately controlled muscle motions, isthmus peristalsis and pumping. The single neuron M4 was necessary and sufficient for isthmus peristalsis. The MC neurons were necessary for normal stimulation of pumping in response to food, but pumping continued and was functional in MC- worms. The remaining 12 neuron types were also unnecessary for functional pumping. No operation we did, including destruction of the entire pharyngeal nervous system, abolished pumping altogether. When we killed all pharyngeal neurons except M4, the worms were viable and fertile, although retarded and starved. Since feeding is one of the few known essential actions controlled by the nervous system, we suggest that most of the C. elegans nervous system is dispensable in hermaphrodites under laboratory conditions. This may explain the ease with which nervous system mutants are isolated and handled in C. elegans.

  20. Luminescent light source for laser pumping and laser system containing same

    DOEpatents

    Hamil, Roy A.; Ashley, Carol S.; Brinker, C. Jeffrey; Reed, Scott; Walko, Robert J.

    1994-01-01

    The invention relates to a pumping lamp for use with lasers comprising a porous substrate loaded with a component capable of emitting light upon interaction of the component with exciting radiation and a source of exciting radiation. Preferably, the pumping lamp comprises a source of exciting radiation, such as an electron beam, and an aerogel or xerogel substrate loaded with a component capable of interacting with the exciting radiation, e.g., a phosphor, to produce light, e.g., visible light, of a suitable band width and of a sufficient intensity to generate a laser beam from a laser material.

  1. 885-nm Pumped Ceramic Nd:YAG Master Oscillator Power Amplifier Laser System

    NASA Technical Reports Server (NTRS)

    Yu, Anthony

    2012-01-01

    The performance of a traditional diode pumped solid-state laser that is typically pumped with 808-nm laser diode array (LDA) and crystalline Nd:YAG was improved by using 885-nm LDAs and ceramic Nd:YAG. The advantage is lower quantum defect, which will improve the thermal loading on laser gain medium, resulting in a higher-performance laser. The use of ceramic Nd:YAG allows a higher Nd dopant level that will make up the lower absorption at the 885-nm wavelength on Nd:YAG. When compared to traditional 808-nm pump, 885-nm diodes will have 30% less thermal load (or wasted heat) and will thus see a similar percentage improvement in the overall laser efficiency. In order to provide a more efficient laser system for future flight missions that require the use of low-repetition- rate (laser pulses, laser diodes such as the 885-nm LDA were used for pumping the Nd:YAG laser crystal. This pumping scheme has many potential advantages for improved reliability, efficiency, thermal management, contamination control, and mechanical flexibility. The advantages of using 885-nm pump diodes in Nd:YAG laser systems are numerous. The epitaxial structures of these 885-nm diodes are aluminum-free. There is a significant reduction in the thermal load generated from the Stokes shift or quantum defects. A Stokes shift is the energetic difference between the pump and laser photons. Pumping at a wavelength band closer to the lasing wavelength can reduce the thermal load by .30% compared to traditional pumping at 808 nm, and increase the optical- to-optical efficiency by the same factor. The slope efficiency is expected to increase with a reduction in the thermal load. The typical crystalline Nd:YAG can be difficult to produce with doping level >1% Nd. To make certain that the absorption at 885 nm is on the same par as the 808-nm diode, the Nd:YAG material needs to be doped with higher concentration of Nd. Ceramic Nd:YAG is the only material that can be tailored

  2. Solar pumped laser

    NASA Technical Reports Server (NTRS)

    Lee, J. H.; Hohl, F.; Weaver, W. R. (Inventor)

    1984-01-01

    A solar pumped laser is described in which the lasant is a gas that will photodissociate and lase when subjected to sunrays. Sunrays are collected and directed onto the gas lasant to cause it to lase. Applications to laser propulsion and laser power transmission are discussed.

  3. Fusion reactor pumped laser

    DOEpatents

    Jassby, Daniel L.

    1988-01-01

    A nuclear pumped laser capable of producing long pulses of very high power laser radiation is provided. A toroidal fusion reactor provides energetic neutrons which are slowed down by a moderator. The moderated neutrons are converted to energetic particles capable of pumping a lasing medium. The lasing medium is housed in an annular cell surrounding the reactor. The cell includes an annular reflecting mirror at the bottom and an annular output window at the top. A neutron reflector is disposed around the cell to reflect escaping neutrons back into the cell. The laser radiation from the annular window is focused onto a beam compactor which generates a single coherent output laser beam.

  4. Explosively pumped laser light

    DOEpatents

    Piltch, Martin S.; Michelotti, Roy A.

    1991-01-01

    A single shot laser pumped by detonation of an explosive in a shell casing. The shock wave from detonation of the explosive causes a rare gas to luminesce. The high intensity light from the gas enters a lasing medium, which thereafter outputs a pulse of laser light to disable optical sensors and personnel.

  5. Explosively pumped laser light

    SciTech Connect

    Piltch, M.S.; Michelott, R.A.

    1991-09-24

    This patent describes a single shot laser pumped by detonation of an explosive in a shell casing. The shock wave from detonation of the explosive causes a rare gas to luminesce. The high intensity light from the gas enters a lasing medium, which thereafter outputs a pulse of laser light to disable optical sensors and personnel.

  6. Off-axis coherently pumped laser

    NASA Technical Reports Server (NTRS)

    Koepf, G. A. (Inventor)

    1984-01-01

    A coherently optically pumped laser system is described. A pump laser beam propagates through a laser medium contained in a degenerate cavity resonator in a controlled multiple round trip fashion in such a way that the unused pump beam emerges from an injection aperture at a different angle from which it enters the resonator. The pump beam is angularly injected off of the central axis of the resonator body whereupon the pump beam alternately undergoes spreading and focusing while pumping the laser medium by a process of resonant absorption. The emergent pump beam can also be used as a second pump beam source by being reinjected back into the cavity or it can be used for pumping another laser.

  7. System of laser pump and synchrotron radiation probe microdiffraction to investigate optical recording process.

    PubMed

    Yasuda, Nobuhiro; Fukuyama, Yoshimitsu; Kimura, Shigeru; Ito, Kiminori; Tanaka, Yoshihito; Osawa, Hitoshi; Matsunaga, Toshiyuki; Kojima, Rie; Hisada, Kazuya; Tsuchino, Akio; Birukawa, Masahiro; Yamada, Noboru; Sekiguchi, Koji; Fujiie, Kazuhiko; Kawakubo, Osamu; Takata, Masaki

    2013-06-01

    We have developed a system of laser-pump and synchrotron radiation probe microdiffraction to investigate the phase-change process on a nanosecond time scale of Ge2Sb2Te5 film embedded in multi-layer structures, which corresponds to real optical recording media. The measurements were achieved by combining (i) the pump-laser system with a pulse width of 300 ps, (ii) a highly brilliant focused microbeam with wide peak-energy width (ΔE∕E ~ 2%) made by focusing helical undulator radiation without monochromatization, and (iii) a precise sample rotation stage to make repetitive measurements. We successfully detected a very weak time-resolved diffraction signal by using this system from 100-nm-thick Ge2Sb2Te5 phase-change layers. This enabled us to find the dependence of the crystal-amorphous phase change process of the Ge2Sb2Te5 layers on laser power. PMID:23822352

  8. Lasant Materials for Blackbody-Pumped Lasers

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J. (Editor); Chen, K. Y. (Editor)

    1985-01-01

    Blackbody-pumped solar lasers are proposed to convert sunlight into laser power to provide future space power and propulsion needs. There are two classes of blackbody-pumped lasers. The direct cavity-pumped system in which the lasant molecule is vibrationally excited by the absorption of blackbody radiation and laser, all within the blackbody cavity. The other system is the transfer blackbody-pumped laser in which an absorbing molecule is first excited within the blackbody cavity, then transferred into a laser cavity when an appropriate lasant molecule is mixed. Collisional transfer of vibrational excitation from the absorbing to the lasing molecule results in laser emission. A workshop was held at NASA Langley Research Center to investigate new lasant materials for both of these blackbody systems. Emphasis was placed on the physics of molecular systems which would be appropriate for blackbody-pumped lasers.

  9. Fusion reactor pumped laser

    DOEpatents

    Jassby, D.L.

    1987-09-04

    A nuclear pumped laser capable of producing long pulses of very high power laser radiation is provided. A toroidal fusion reactor provides energetic neutrons which are slowed down by a moderator. The moderated neutrons are converted to energetic particles capable of pumping a lasing medium. The lasing medium is housed in an annular cell surrounding the reactor. The cell includes an annular reflecting mirror at the bottom and an annular output window at the top. A neutron reflector is disposed around the cell to reflect escaping neutrons back into the cell. The laser radiation from the annular window is focused onto a beam compactor which generates a single coherent output laser beam. 10 figs.

  10. /sup 3/He functions in tokamak-pumped laser systems

    SciTech Connect

    Jassby, D.L.

    1986-10-01

    /sup 3/He placed in an annular cell around a tokamak fusion generator can convert moderated fusion neutrons to energetic ions by the /sup 3/He(n,p)T reaction, and thereby excite gaseous lasants mixed with the /sup 3/He while simultaneously breeding tritium. The total /sup 3/He inventory is about 4 kg for large tokamak devices. Special configurations of toroidal-field magnets, neutron moderators and beryllium reflectors are required to permit nearly uniform neutron current into the laser cell with minimal attenuation. The annular laser radiation can be combined into a single output beam at the top of the tokamak.

  11. Holmium laser pumped with a neodymium laser

    SciTech Connect

    Bowman, S.R.; Rabinovich, W.S.

    1991-07-30

    This patent describes a solid-state laser device. It comprises a holmium laser having a first host material doped with an amount of holmium ions sufficient to produce an output laser emission at about 3 {mu}m when the holmium ions in the holmium laser are pumped by a pump beam at a wavelength of about 1.1 {mu}m; and neodymium laser pump source means for supplying a pump beam to pump the holmium ions in the holmium laser at a wavelength of about 1.1 {mu}m.

  12. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Kim, K. H.; Stock, L. V.

    1986-01-01

    In order to evaluate the feasibility of the solar pumped dye laser, the parametric study of a dye laser amplifier pumped by a solar simulator and flashlamp was carried out, and the amplifier gains were measured at various pump beam irradiances on the dye cell. Rhodamine 6G was considered as a candidate for the solar pumped laser because of its good utilization of the solar spectrum and high quantum efficiency. The measurement shows that a solar concentration of 20,000 is required to reach the threshold of the dye. The work to construct a kinetic model algorithm which predicts the output parameter of laser was progressed. The kinetic model was improved such that there is good agreement between the theoretical model and experimental data for the systems defined previously as flashlamp pumped laser oscillator, and the long path length solar pumped laser.

  13. Nd:YAG laser side pumped by diode laser arrays

    NASA Astrophysics Data System (ADS)

    Tan, Hua; Huang, Weiling; Zhou, Zhouyou; Wang, Hailin; Cao, Hongbing; Wang, Ying

    1999-09-01

    The major limitation of flashlamp-pumped solid-state lasers is the low overall efficiency. Replacing flashlamps with high power laser diodes allows an increase of system efficiency by over an order of magnitude. Because of the thermally induced stress fracture of the laser materials, power-scaling possibilities of end-pumped configurations are limited. Therefore side pump geometry has to be used for high power laser. The theory and the design of high power diode side-pumped Nd:YAG laser system is described. The Nd:YAG rod is side-pumped by diode laser arrays with wavelength at 808 nm. We analyze the result of our experiments and make some conclusions about the design of side-pumped laser.

  14. Laser Doppler velocimetry for continuous flow solar-pumped iodine laser system

    NASA Technical Reports Server (NTRS)

    Tabibi, Bagher M.; Lee, Ja H.

    1991-01-01

    A laser Doppler velocimetry (LDV) system was employed to measure the flow velocity profile of iodide vapor inside laser tubes of 36 mm ID and 20 mm ID. The LDV, which was operated in the forward scatter mode used a low power (15 mW) He-Ne laser beam. Velocity ranges from 1 m/s was measured to within one percent accuracy. The flow velocity profile across the laser tube was measured and the intensity of turbulence was determined. The flow of iodide inside the laser tube demonstrated a mixture of both turbulence and laminar flow. The flowmeter used for the laser system previously was calibrated with the LDV and found to be in good agreement.

  15. High power diode pumped alkali vapor lasers

    NASA Astrophysics Data System (ADS)

    Zweiback, J.; Krupke, B.

    2008-05-01

    Diode pumped alkali lasers have developed rapidly since their first demonstration. These lasers offer a path to convert highly efficient, but relatively low brightness, laser diodes into a single high power, high brightness beam. General Atomics has been engaged in the development of DPALs with scalable architectures. We have examined different species and pump characteristics. We show that high absorption can be achieved even when the pump source bandwidth is several times the absorption bandwidth. In addition, we present experimental results for both potassium and rubidium systems pumped with a 0.2 nm bandwidth alexandrite laser. These data show slope efficiencies of 67% and 72% respectively.

  16. Solar powered blackbody-pumped lasers

    NASA Astrophysics Data System (ADS)

    Christiansen, Walter H.; Sirota, J. M.

    1991-02-01

    A concept for a solar-powered laser is presented which utilizes an intermediate blackbody cavity to provide a uniform optical pumping environment for the lasant, typically CO or CO2 or possibly a solid state laser medium. High power cw blackbody- pumped lasers with efficiencies on the order of 20 percent or more are feasible. The physical basis of this idea is reviewed. Small scale experiments using a high temperature oven as the optical pump have been carried out with gas laser mixtures. Detailed calculations showing a potential efficiency of 35 percent for blackbody pumped Nd:YAG system are discussed.

  17. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Kim, K. H.; Stock, L. V.

    1987-01-01

    The improvement on the collection system of the Tarmarack Solar Simulator beam was attemped. The basic study of evaluating the solid state laser materials for the solar pumping and also the work to construct a kinetic model algorithm for the flashlamp pumped iodine lasers were carried out. It was observed that the collector cone worked better than the lens assembly in order to collect the solar simulator beam and to focus it down to a strong power density. The study on the various laser materials and their lasing characteristics shows that the neodymium and chromium co-doped gadolinium scandium gallium garnet (Nr:Cr:GSGG) may be a strong candidate for the high power solar pumped solid state laser crystal. On the other hand the improved kinetic modeling for the flashlamp pumped iodine laser provides a good agreement between the theoretical model and the experimental data on the laser power output, and predicts the output parameters of a solar pumped iodine laser.

  18. Direct solar-pumped iodine laser amplifier

    NASA Astrophysics Data System (ADS)

    Han, Kwang S.; Kim, K. H.; Stock, L. V.

    1987-02-01

    The improvement on the collection system of the Tarmarack Solar Simulator beam was attemped. The basic study of evaluating the solid state laser materials for the solar pumping and also the work to construct a kinetic model algorithm for the flashlamp pumped iodine lasers were carried out. It was observed that the collector cone worked better than the lens assembly in order to collect the solar simulator beam and to focus it down to a strong power density. The study on the various laser materials and their lasing characteristics shows that the neodymium and chromium co-doped gadolinium scandium gallium garnet (Nr:Cr:GSGG) may be a strong candidate for the high power solar pumped solid state laser crystal. On the other hand the improved kinetic modeling for the flashlamp pumped iodine laser provides a good agreement between the theoretical model and the experimental data on the laser power output, and predicts the output parameters of a solar pumped iodine laser.

  19. Alexandrite laser pumped by semiconductor lasers

    SciTech Connect

    Scheps, R.; Gately, B.M.; Myers, J.F. ); Krasinski, J.S. ); Heller, D.F. )

    1990-06-04

    We report the first operation of a direct diode-pumped tunable chromium-doped solid-state laser. A small alexandrite (Cr:BeAl{sub 2}O{sub 4}) crystal was longitudinally pumped by two visible laser diodes. The threshold pump power was 12 mW using the {ital R}{sub 1} line at 680.4 nm for the pump transition, and the slope efficiency was 25%. The measured laser output bandwidth was 2.1 nm.

  20. Solar-pumped solid state Nd lasers

    NASA Technical Reports Server (NTRS)

    Williams, M. D.; Zapata, L.

    1985-01-01

    Solid state neodymium lasers are considered candidates for space-based polar-pumped laser for continuous power transmission. Laser performance for three different slab laser configurations has been computed to show the excellent power capability of such systems if heat problems can be solved. Ideas involving geometries and materials are offered as potential solutions to the heat problem.

  1. Laser beam control and diagnostic systems for the copper-pumped dye laser system at Lawrence Livermore National Laboratory

    SciTech Connect

    Bliss, E.S.; Peterson, R.L.; Salmon, J.T.; Thomas, R.A.

    1992-11-01

    The laser system described in the previous paper is used for experiments in which success requires tight tolerances on beam position, direction, and wavefront. Indeed, the optimum performance of the laser itself depends on careful delivery of copper laser light to the dye amplifiers, precise propagation of dye laser beams through restricted amplifier apertures, and accurate monitoring of laser power at key locations. This paper describes the alignment systems, wavefront correction systems, and laser diagnostics systems which ensure that the control requirements of both the laser and associated experiments are met. Because laser isotope separation processes utilize more than one wavelength, these systems monitor and control multiple wavelengths simultaneously.

  2. System of laser pump and synchrotron radiation probe microdiffraction to investigate optical recording process

    SciTech Connect

    Yasuda, Nobuhiro; Fukuyama, Yoshimitsu; Osawa, Hitoshi; Kimura, Shigeru; Ito, Kiminori; Tanaka, Yoshihito; Matsunaga, Toshiyuki; Kojima, Rie; Hisada, Kazuya; Tsuchino, Akio; Birukawa, Masahiro; Yamada, Noboru; Sekiguchi, Koji; Fujiie, Kazuhiko; Kawakubo, Osamu; Takata, Masaki

    2013-06-15

    We have developed a system of laser-pump and synchrotron radiation probe microdiffraction to investigate the phase-change process on a nanosecond time scale of Ge{sub 2}Sb{sub 2}Te{sub 5} film embedded in multi-layer structures, which corresponds to real optical recording media. The measurements were achieved by combining (i) the pump-laser system with a pulse width of 300 ps, (ii) a highly brilliant focused microbeam with wide peak-energy width ({Delta}E/E {approx} 2%) made by focusing helical undulator radiation without monochromatization, and (iii) a precise sample rotation stage to make repetitive measurements. We successfully detected a very weak time-resolved diffraction signal by using this system from 100-nm-thick Ge{sub 2}Sb{sub 2}Te{sub 5} phase-change layers. This enabled us to find the dependence of the crystal-amorphous phase change process of the Ge{sub 2}Sb{sub 2}Te{sub 5} layers on laser power.

  3. Activation of theMercury Laser System: A Diode-Pumped Solid-State Laser Driver for Inertial Fusion

    SciTech Connect

    Bayramian, A J; Beach, R J; Bibeau, C; Ebbers, C A; Freitas, B L; Kanz, V K; Payne, S A; Schaffers, K I; Skulina, K M; Smith, L K; Tassano, J B

    2001-09-10

    Initial measurements are reported for the Mercury laser system, a scalable driver for rep-rated inertial fusion energy. The performance goals include 10% electrical efficiency at 10 Hz and 100 J with a 2-10 ns pulse length. We report on the first Yb:S-FAP crystals grown to sufficient size for fabricating full size (4 x 6 cm) amplifier slabs. The first of four 160 kW (peak power) diode arrays and pump delivery systems were completed and tested with the following results: 5.5% power droop over a 0.75 ms pulse, 3.95 nm spectral linewidth, far field divergence of 14.0 mrad and 149.5 mrad in the microlensed and unmicrolensed directions respectively, and 83% optical-to-optical transfer efficiency through the pump delivery system.

  4. a Mathematical Model of the Dynamics of AN Optically Pumped Codoped Solid State Laser System

    NASA Astrophysics Data System (ADS)

    Wangler, Thomas Gerard

    1990-01-01

    This is a study of a mathematical model for the dynamics of an optically pumped codoped solid state laser system. The model comprises five first order, nonlinear, coupled, ordinary differential equations which describe the temporal evolution of the dopant electron populations in the laser crystal as well as the photon density in the laser cavity. The analysis of the model is conducted in three parts. First, a detailed explanation of the modeling process is given and the full set of rate equations is obtained. The model is then simplified and certain qualitative properties of the solution are obtained. In the second part the equilibrium solutions are obtained and a local stability analysis is performed. The system of rate equations is solved numerically and the effects, on the solution, of varying physical parameters is discussed. Finally, the third part addresses the oscillatory behavior of the system by "tracking" the eigenvalues of the linearized system. A comparison is made between the frequency of oscillations in the linear and nonlinear system. Pertinent physical processes--back transfer, Q-switching, and up -conversion--are then examined. The laser system consists of thulium and holmium ions in a YAG crystal operated in a Fabrey-Perot cavity. All computer programs were written in FORTRAN and currently run on either an IBM-PC or a DEC VAX 11/750.

  5. A mathematical model of the dynamics of an optically pumped codoped solid-state laser system

    SciTech Connect

    Wangler, T.G.

    1990-01-01

    This is a study of a mathematical model for the dynamics of an optically pumped codoped solid state laser system. The model comprises five first order, nonlinear, coupled, ordinary differential equations which describe the temporal evolution of the dopant electron populations in the laser crystal as well as the photon density in the laser cavity. The analysis of the model is conducted in three parts. First, a detailed explanation of the modeling process is given and the full set of rate equations is obtained. The model is then simplified and certain qualitative properties of the solution are obtained. In the second part the equilibrium solutions are obtained and local stability analysis is performed. The system of rate equations is solved numerically and the effects, on the solution, of varying physical parameters is discussed. Finally, the third part addresses the oscillatory behavior of the system by tracking the eigenvalues of the linearized system. A comparison is made between the frequency of oscillations in the linear and nonlinear system. Pertinent physical processes - back transfer, Q-switching, and up-conversion - are then examined. The laser system consists of thulium and holmium ions in YAG crystal operated in a Fabrey-Perot cavity. All computer programs were written in FORTRAN and currently run on either an IBM-PC or a DEC VAX 11/750.

  6. Analysis of a 10 megawatt space-based solar-pumped neodymium laser system

    NASA Technical Reports Server (NTRS)

    Kurweg, U. H.

    1984-01-01

    A ten megawatt solar-pumped continuous liquid laser system for space applications is examined. It is found that a single inflatable mirror of 434 m diameter used in conjunction with a conical secondary concentrator is sufficient to side pump a liquid neodymium lasant in an annular tube of 6 m length and 1 m outer and 0.8 m inner diameter. About one fourth of intercepted radiation converging on the laser tube is absorbed and one fifth of this radiation is effective in populating the upper levels. The liquid lasant is flowed through the annular laser cavity at 1.9 m/s and is cooled via a heat exchanger and a large radiator surface comparable in size to the concentrating mirror. The power density of incident light within the lasant of approximately 68 watt/cu cm required for cw operation is exceeded in the present annular configuration. Total system weight corresponds to 20,500 kg and is thus capable of being transported to near Earth orbit by a single shuttle flight.

  7. A review of laser-pumped infrared lasers

    NASA Technical Reports Server (NTRS)

    Chen, K. Y.

    1985-01-01

    The lasing mechanisms are reviewed of molecules that have demonstrated laser action in the laboratories with laser emissions in the spectral range from 3 to 35 microns. A list of lasants and laser mechanisms are defined. The pumping sources for these lasers are mainly infrared lasers; however, the case in which excitation of bromine atoms at 2.71 microns by a flashlamp as energy input is also included in the review. A conceptual drawing of lasing mechanisms is shown. Three pumping mechanisms are shown, the first being the direct-pumped system in which the lasant molecule absorbs the infrared radiation from pump laser directly, and it is excited into the upper laser level from the ground state. The second system is the indirect-pumped system where the infrared-pump laser first excites an absorbing molecule which stores its vibrational energy. Through collision this energy is transferred to the lasant molecule, populating the upper laser level. In the third system, i.e., in a Br2-CO2 mixture, a flashlamp replaces the infrared laser as the pump source for the absorbing molecule.

  8. Initial conceptual design study of self-critical nuclear pumped laser systems

    NASA Technical Reports Server (NTRS)

    Rodgers, R. J.

    1979-01-01

    An analytical study of self-critical nuclear pumped laser system concepts was performed. Primary emphasis was placed on reactor concepts employing gaseous uranium hexafluoride (UF6) as the fissionable material. Relationships were developed between the key reactor design parameters including reactor power level, critical mass, neutron flux level, reactor size, operating pressure, and UF6 optical properties. The results were used to select a reference conceptual laser system configuration. In the reference configuration, the 3.2 m cubed lasing volume is surrounded by a graphite internal moderator and a region of heavy water. Results of neutronics calculations yield a critical mass of 4.9 U(235) in the form (235)UF6. The configuration appears capable of operating in a continuous steady-state mode. The average gas temperature in the core is 600 K and the UF6 partial pressure within the lasing volume is 0.34 atm.

  9. Detectable distance calculations for a visual navigation system using a scanning semiconductor laser with electronic pumping.

    PubMed

    Kaloshin, G A; Shishkin, S A

    2011-07-10

    Results of detectable distance calculations for a visual navigation system based on a scanning semiconductor laser with electronic pumping (SSLEP) are presented. A semiconductor crystal in the laser is pumped with an electron beam, which is scanned across the crystal in the television-frame scan mode. The navigation system forms three orientation sectors with radiation wavelengths λ=0.52, 0.57, and 0.63 μm. Herein, calculations of energetic characteristics of output radiation are performed for the navigation system described above. The calculations were performed using the Range software package, which considers microphysical and optical characteristics of aerosol and observation path geometry for the case of coastal environment. Finally, comparison of results of the calculations with data obtained in marine and flight experiments is presented. It is demonstrated that minor discrepancies between calculated and measured values of detectable distance are observed in the coastal haze at lower values of meteorological visibility range S(m). As S(m) increases, the discrepancies become significant. PMID:21743551

  10. Femtosecond wavelength-tunable OPCPA system based on picosecond fiber laser seed and picosecond DPSS laser pump.

    PubMed

    Danilevičius, R; Zaukevičius, A; Budriūnas, R; Michailovas, A; Rusteika, N

    2016-07-25

    We present a compact and stable femtosecond wavelength-tunable optical parametric chirped pulse amplification (OPCPA) system. A novel OPCPA front-end was constructed using a multi-channel picosecond all-in-fiber source for seeding DPSS pump laser and white light supercontinuum generation. Broadband chirped pulses were parametrically amplified up to 1 mJ energy and compressed to less than 40 fs duration. Pulse wavelength tunability in the range from 680 nm to 930 nm was experimentally demonstrated. PMID:27464199

  11. Picosecond DPSS laser technology for OPCPA pumping

    NASA Astrophysics Data System (ADS)

    Vaupel, Andreas; Bodnar, Nathan; Webb, Benjamin; Shah, Lawrence; Richardson, Martin

    2014-02-01

    We present the design and challenges of a diode-pumped solid-state (DPSS) system to amplify picosecond pulses to high pulse energies and high average powers. We discuss our implemented solutions to mitigate thermal effects and present the obtained performance of the picosecond pulse amplification at the multi-10-MW level. Our here presented picosecond DPSS laser is well suited for pumping an optical parametric chirped-pulse amplification (OPCPA) system. Several laser technologies have been employed to pump OPCPA systems and we show how our DPSS system compares in performance to the other approaches.

  12. Primary investigations on the potential of a novel diode pumped Er:YAG laser system for middle ear surgery

    NASA Astrophysics Data System (ADS)

    Stock, Karl; Wurm, Holger; Hausladen, Florian

    2016-02-01

    Flashlamp pumped Er:YAG lasers are successfully used clinically for both precise soft and hard tissue ablation. Since several years a novel diode pumped Er:YAG laser system (Pantec Engineering AG) is available, with mean laser power up to 40 W and pulse repetition rate up to 1 kHz. The aim of the study was to investigate the suitability of the laser system specifically for stapedotomy. Firstly an experimental setup was realized with a beam focusing unit and a computer controlled translation stage to move the samples (slices of porcine bone) with a defined velocity while irradiation with various laser parameters. A microphone was positioned in a defined distance to the ablation point and the resulting acoustic signal of the ablation process was recorded. For comparison, measurements were also performed with a flash lamp pumped Er:YAG laser system. After irradiation the resulting ablation quality and efficacy were determined using light microscopy. Using a high speed camera and "Töpler-Schlierentechnik" the cavitation bubble in water after perforation of a bone slice was investigated. The results show efficient bone ablation using the diode pumped Er:YAG laser system. Also a decrease of the sound level and of the cavitation bubble volume was observed with decreasing pulse duration. Higher repetition rates lead to a slightly increase of thermal side effects but have no influence on the ablation efficiency. In conclusion, these first experiments demonstrate the high potential of the diode pumped Er:YAG laser system for use in middle ear surgery.

  13. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Hwang, In Heon; Stock, Larry V.

    1989-01-01

    This semiannual progress report covers the period from September 1, 1988 to February 28, 1989 under NASA grant NAG-1-441 entitled, Direct Solar-Pumped Iodine Laser Amplifier. During this period, the research effort was concentrated on the solar pumped master oscillator power amplifier (MOPA) system using n-C3F7I. In the experimental work, the amplification measurement was conducted to identify the optimum conditions for amplification of the center's Vortek solar simulator pumped iodine laser amplifier. A modeling effort was also pursued to explain the experimental results in the theoretical work. The amplification measurement of the solar simulator pumped iodine laser amplifier is the first amplification experiment on the continuously pumped amplifier. The small signal amplification of 5 was achieved for the triple pass geometry of the 15 cm long solar simulator pumped amplifier at the n-C3F7I pressure of 20 torr, at the flow velocity of 6 m/sec and at the pumping intensity of 1500 solar constants. The XeCl laser pumped iodine laser oscillator, which was developed in the previous research, was employed as the master oscillator for the amplification measurement. In the theoretical work, the rate equations of the amplifier was established and the small signal amplification was calculated for the solar simulator pumped iodine laser amplifier. The amplification calculated from the kinetic equations with the previously measured rate coefficients reveals very large disagreement with experimental measurement. Moreover, the optimum condition predicted by the kinetic equation is quite discrepant with that measured by experiment. This fact indicates the necessity of study in the measurement of rate coefficients of the continuously pumped iodine laser system.

  14. Nuclear pumped gas laser research

    NASA Technical Reports Server (NTRS)

    Thom, K.

    1976-01-01

    Nuclear pumping of lasers by fission-fragments from nuclear chain reactions is discussed. Application of the newly developed lasers to spacecraft propulsion or onboard power, to lunar bases for industrial processing, and to earth for utilization of power without pollution and hazards is envisioned. Emphasis is placed on the process by which the fission-fragement kinetic energy is converted into laser light.

  15. Solar-pumped laser for free space power transmission

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.

    1989-01-01

    Laser power transmission; laser systems; space-borne and available lasers; 2-D and 1 MW laser diode array systems; technical issues; iodine solar pumped laser system; and laser power transmission applications are presented. This presentation is represented by viewgraphs only.

  16. Investigations on the potential of a novel diode pumped Er:YAG laser system for dental applications

    NASA Astrophysics Data System (ADS)

    Stock, Karl; Hausladen, Florian; Hibst, Raimund

    2012-01-01

    The successful clinical application of the Er:YAG-laser in dentistry is well known, documented by numerous published studies. These lasers are flash lamp pumped systems and emit pulses of typically some 100 μs duration with energies of up to 1 J. Pulse repetition rates can reach up to 100Hz, and mean powers are up to about 8W. As an alternative to these laser systems recently a novel diode pumped Er:YAG laser system (Pantec Engineering AG) became available. This laser can provide a pulse repetition rate up to 2kHz and a mean laser power up to 15W. The aim of the presented study is to investigate the effect of this laser system on dental hard and soft tissue at various irradiation parameters, particular at repetition rates more than 100 Hz. At first an appropriate experimental set-up was realized with a beam delivery and focusing unit, a computer controlled stepper unit with sample holder, and a shutter unit. The stepper unit allows to move the samples (dentin or enamel slides of extracted human teeth, chicken breast, pig bone) with a defined velocity during irradiation by various laser parameters. For rinsing the sample surface a water spray was also included. The laser produced grooves and cuts were analyzed by light microscopy and laser scanning microscopy regarding to the ablation quality, geometry, ablation efficacy, and thermal effects. The grooves in dentin and enamel show a rough surface, typical for Er:YAG laser ablation. The craters are slightly cone shaped with sharp edges on the surface. Water cooling is essential to prevent thermal injury. The ablation efficacy in dentin is comparable to literature values of the flash lamp pumped Er:YAG laser. The cutting of bone and soft tissue is excellent and appears superior to earlier results obtained with flash lamp pumped system. As a further advantage, the broad range of repetition rates allows to widely vary the thermal side effects. In conclusion, these first experiments with a diode pumped Er:YAG laser

  17. Solar-pumped laser on the Space Station

    SciTech Connect

    Arashi, H.; Oka, Y.; Ishigame, M.

    1985-01-01

    A solid state solar pumped laser system to be used on the Space Station is described. The system is based on an experimental version of a solar pumped Nd:YAG laser which has achieved a maximum power in excess of 18 W in multi-mode. The laser is powered by a paraboloid solar radiation concentrator. A solar pumped gas laser system is recommended for applications requiring a higher output power. Applications of a laser on board the Space Station include optical communication; laser propulsion; energy conversion; and high speed laser processing. Detailed schematic drawings of the solid state and gas laser designs are provided.

  18. Investigations on the potential of a low power diode pumped Er:YAG laser system for oral surgery

    NASA Astrophysics Data System (ADS)

    Stock, Karl; Wurm, Holger; Hausladen, Florian; Wagner, Sophia; Hibst, Raimund

    2015-02-01

    Flash lamp pumped Er:YAG-lasers are used in clinical practice for dental applications successfully. As an alternative, several diode pumped Er:YAG laser systems (Pantec Engineering AG) become available, with mean laser power of 2W, 15W, and 30W. The aim of the presented study is to investigate the potential of the 2W Er:YAG laser system for oral surgery. At first an appropriate experimental set-up was realized with a beam delivery and both, a focusing unit for non-contact tissue cutting and a fiber tip for tissue cutting in contact mode. In order to produce reproducible cuts, the samples (porcine gingiva) were moved by a computer controlled translation stage. On the fresh samples cutting depth and quality were determined by light microscopy. Afterwards histological sections were prepared and microscopically analyzed regarding cutting depth and thermal damage zone. The experiments show that low laser power ≤ 2W is sufficient to perform efficient oral soft tissue cutting with cut depth up to 2mm (sample movement 2mm/s). The width of the thermal damage zone can be controlled by the irradiation parameters within a range of about 50μm to 110μm. In general, thermal injury is more pronounced using fiber tips in contact mode compared to the focused laser beam. In conclusion the results reveal that even the low power diode pumped Er:YAG laser is an appropriate tool for oral surgery.

  19. Analysis of Nd3+:glass, solar-pumped, high-powr laser systems

    NASA Technical Reports Server (NTRS)

    Zapata, L. E.; Williams, M. D.

    1989-01-01

    The operating characteristics of Nd(3+):glass lasers energized by a solar concentrator were analyzed for the hosts YAG, silicate glass, and phosphate glass. The modeling is based on the slab zigzag laser geometry and assumes that chemical hardening methods for glass are successful in increasing glass hardness by a factor of 4. On this basis, it was found that a realistic 1-MW solar-pumped laser might be constructed from phosphate glass 4 sq m in area and 2 mm thick. If YAG were the host medium, a 1-MW solar-pumped laser need only be 0.5 sq m in area and 0.5 cm thick, which is already possible. In addition, Nd(3+) doped glass fibers were found to be excellent solar-pumped laser candidates. The small diameter of fibers eliminates thermal stress problems, and if their diameter is kept small (10 microns), they propagate a Gaussian single mode which can be expanded and transmitted long distances in space. Fiber lasers could then be used for communications in space or could be bundled and the individual beams summed or phase-matched for high-power operation.

  20. Fusion pumped laser

    DOEpatents

    Pappas, D.S.

    1987-07-31

    The apparatus of this invention may comprise a system for generating laser radiation from a high-energy neutron source. The neutron source is a tokamak fusion reactor generating a long pulse of high-energy neutrons and having a temperature and magnetic field effective to generate a neutron flux of at least 10/sup 15/ neutrons/cm/sup 2//center dot/s. Conversion means are provided adjacent the fusion reactor at a location operable for converting the high-energy neutrons to an energy source with an intensity and energy effective to excite a preselected lasing medium. A lasing medium is spaced about and responsive to the energy source to generate a population inversion effective to support laser oscillations for generating output radiation. 2 figs., 2 tabs.

  1. Optically pumped molecular bromine laser. Master's thesis

    SciTech Connect

    Morrison, J.W.

    1990-12-01

    An optically pumped molecular bromine laser was studied to investigate the quenching kinetics state of Br2. This included characterization of the pressure dependence of the laser output power. The approach was to excite molecular bromine in a sealed cell with a Nd:YAG pumped dye laser. Unresolved side fluorescence and amplified stimulated emission (ASE) spectra were recorded. ASE offered the advantage of a simpler optical system with no externally induced wavelength dependencies. Stimulated emission as a signal monitor offered greater resolution than side fluorescence spectra and facilitated spectroscopic assignment. (JS)

  2. Diode laser-pumped solid-state lasers

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1988-01-01

    An evaluation is made of the consequences for solid-state lasers of novel diode laser-pumping technology. Diode laser-pumped neodymium lasers have operated at an electrical-to-optical efficiency of 10 percent in a single spatial mode, with linewidths of less than 10 kHz, and with a spectral power brightness sufficiently great to allow frequency extension by harmonic generation in nonlinear crystals; this has yielded green and blue sources of coherent radiation. Q-switched operation with kW peak powers and mode-locked operation with 10-picosec pulse widths have also been demonstrated. All-solid-state lasers at prices comparable to those of current flash-lamp-pumped laser systems are foreseen, as are power levels exceeding 1 kW, for coherent radar, global satellite sensing, and micromachining.

  3. Bidirectional pumped high power Raman fiber laser.

    PubMed

    Xiao, Q; Yan, P; Li, D; Sun, J; Wang, X; Huang, Y; Gong, M

    2016-03-21

    This paper presents a 3.89 kW 1123 nm Raman all-fiber laser with an overall optical-to-optical efficiency of 70.9%. The system consists of a single-wavelength (1070nm) seed and one-stage bidirectional 976 nm non-wavelength-stabilized laser diodes (LDs) pumped Yb-doped fiber amplifier. The unique part of this system is the application of non-wavelength-stabilized LDs in high power bidirectional pumping configuration fiber amplifier via refractive index valley fiber combiners. This approach not only increases the pump power, but also shortens the length of fiber by avoiding the usage of multi-stage amplifier. Through both theoretical research and experiment, the bidirectional pumping configuration presented in this paper proves to be able to convert 976 nm pump laser to 1070 nm laser via Yb3+ transfer, which is then converted into 1123 nm Raman laser via the first-order Raman effect without the appearance of any higher-order Raman laser. PMID:27136862

  4. Nuclear-Pumped Lasers. [efficient conversion of energy liberated in nuclear reactions to coherent radiation

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The state of the art in nuclear pumped lasers is reviewed. Nuclear pumped laser modeling, nuclear volume and foil excitation of laser plasmas, proton beam simulations, nuclear flashlamp excitation, and reactor laser systems studies are covered.

  5. High-energy transversely pumped alkali vapor laser

    NASA Astrophysics Data System (ADS)

    Zweiback, J.; Komashko, A.

    2011-03-01

    We report on the results from our transversely pumped alkali laser. This system uses an Alexandrite laser to pump a stainless steel laser head. The system uses methane and helium as buffer gasses. Using rubidium, the system produced up to 40 mJ of output energy when pumped with 63 mJ. Slope efficiency was 75%. Using potassium as the lasing species the system produced 32 mJ and a 53% slope efficiency.

  6. Development and application investigation of an ICSHG 532 nm diode-pumped solid-state laser system

    NASA Astrophysics Data System (ADS)

    Nhat Khoa Phan, Thanh; Tu, Trung Chan; Thuat Nguyen, Tran; Chien Nguyen, Thanh; Chien Dang, Mau

    2011-12-01

    A diode-pump solid-state laser system emitting a 532 nm beam has been developed. The pump source is an 808 nm diode laser, which has gained wide acceptance in research as well as in commercial production due to its effectiveness and reasonable price. The active medium was chosen to be Nd:YVO4 (neodymium-doped yttrium orthovanadate), a material with many advantages over traditional Nd:YAG (neodymium-doped yttrium aluminum garnet) such as a low lasing threshold and linearly polarized beam. However, the thermal conductivity of Nd:YVO4 is not as good as Nd:YAG, thus the thermal lens effect inside Nd:YVO4 under high pumping intensity becomes severe and detrimental to the laser performance. Our work showed that careful adjustments of Nd:YVO4 temperature as well as of the cavity's parameters played an important role in the performance of the laser. Potassium titanyl phosphate (KTP), a nonlinear optics crystal, was used to convert the fundamental 1064 nm laser radiation from Nd:YVO4 into 532 nm. The 532 nm laser beam has been successfully proven to cut wood, plastic and aluminum.

  7. Performance assessment of a new laser system for efficient spin exchange optical pumping in a spin maser measurement of 129Xe EDM

    NASA Astrophysics Data System (ADS)

    Funayama, C.; Furukawa, T.; Sato, T.; Ichikawa, Y.; Ohtomo, Y.; Sakamoto, Y.; Kojima, S.; Suzuki, T.; Hirao, C.; Chikamori, M.; Hikota, E.; Tsuchiya, M.; Yoshimi, A.; Bidinosti, C. P.; Ino, T.; Ueno, H.; Matsuo, Y.; Fukuyama, T.; Asahi, K.

    2015-11-01

    We demonstrate spin-exchange optical pumping of 129Xe atoms with our newly made laser system. The new laser system was prepared to provide higher laser power required for the stable operation of spin maser oscillations in the 129Xe EDM experiment. We studied the optimum cell temperature and pumping laser power to improve the degree of 129Xe spin polarization. The best performance was achieved at the cell temperature of 100 ∘C with the presently available laser power of 1 W. The results show that a more intense laser is required for further improvement of the spin polarization at higher cell temperatures in our experiment.

  8. Diode-pumped CW molecular lasers

    NASA Astrophysics Data System (ADS)

    Wellegehausen, B.; Luhs, W.

    2016-05-01

    First continuous laser oscillation on many lines in the range of 533-635 nm on different transitions of Na2 and Te2 molecules has been obtained, optically pumped with common cw blue emitting InGaN diode lasers operating around 445 and 460 nm. Spectral narrowing of the diode laser is achieved with a beamsplitter and grating setup, allowing use of more than 50 % of the diode power. Operation conditions and properties of the laser systems are presented, and perspectives for the realization of compact low cost molecular lasers are discussed.

  9. Reactor-pumped laser experimental results

    SciTech Connect

    Hebner, G.A.; Hays, G.N.

    1994-12-31

    Reactor pumped lasers have the potential to be scaled to multi-megawatt power levels with long run times. In proposed designs, the laser will be capable of output powers of several megawatts of power for run times of several hours. Such a laser would have many diverse applications such as material processing, space debris removal and power beaming to geosynchronous satellites or the moon. However, before such systems can be designed, fundamental laser parameters such as small signal gain, saturation intensity and efficiency must be determined over a wide operational parameter space. The authors have recently measured fundamental laser parameters for a selection of nuclear pumped visible and near IR laser transitions in atomic neon, argon and xenon. An overview of the results of this investigation will be presented.

  10. Selective Emitter Pumped Rare Earth Laser

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L. (Inventor); Patton, Martin O. (Inventor)

    2001-01-01

    A selective emitter pumped rare earth laser provides an additional type of laser for use in many laser applications. Rare earth doped lasers exist which are pumped with flashtubes or laser diodes. The invention uses a rare earth emitter to transform thermal energy input to a spectral band matching the absorption band of a rare earth in the laser in order to produce lasing.

  11. Heat pump processes induced by laser radiation

    NASA Technical Reports Server (NTRS)

    Garbuny, M.; Henningsen, T.

    1980-01-01

    A carbon dioxide laser system was constructed for the demonstration of heat pump processes induced by laser radiation. The system consisted of a frequency doubling stage, a gas reaction cell with its vacuum and high purity gas supply system, and provisions to measure the temperature changes by pressure, or alternatively, by density changes. The theoretical considerations for the choice of designs and components are dicussed.

  12. Transverse pumped laser amplifier architecture

    DOEpatents

    Bayramian, Andrew James; Manes, Kenneth R.; Deri, Robert; Erlandson, Alvin; Caird, John; Spaeth, Mary L.

    2015-05-19

    An optical gain architecture includes a pump source and a pump aperture. The architecture also includes a gain region including a gain element operable to amplify light at a laser wavelength. The gain region is characterized by a first side intersecting an optical path, a second side opposing the first side, a third side adjacent the first and second sides, and a fourth side opposing the third side. The architecture further includes a dichroic section disposed between the pump aperture and the first side of the gain region. The dichroic section is characterized by low reflectance at a pump wavelength and high reflectance at the laser wavelength. The architecture additionally includes a first cladding section proximate to the third side of the gain region and a second cladding section proximate to the fourth side of the gain region.

  13. Transverse pumped laser amplifier architecture

    DOEpatents

    Bayramian, Andrew James; Manes, Kenneth; Deri, Robert; Erlandson, Al; Caird, John; Spaeth, Mary

    2013-07-09

    An optical gain architecture includes a pump source and a pump aperture. The architecture also includes a gain region including a gain element operable to amplify light at a laser wavelength. The gain region is characterized by a first side intersecting an optical path, a second side opposing the first side, a third side adjacent the first and second sides, and a fourth side opposing the third side. The architecture further includes a dichroic section disposed between the pump aperture and the first side of the gain region. The dichroic section is characterized by low reflectance at a pump wavelength and high reflectance at the laser wavelength. The architecture additionally includes a first cladding section proximate to the third side of the gain region and a second cladding section proximate to the fourth side of the gain region.

  14. Progress in discharge-pumped excimer lasers

    NASA Astrophysics Data System (ADS)

    Pike, Charles T.

    1993-04-01

    This paper describes recent results achieved in the development of discharge pumped excimer lasers at the Textron Defense Systems organization (formerly the Avco Research Laboratory). Included is a description of a KrF laser with more than one Joule output at 2.4% efficiency, a 200 mJ XeCl laser operating with a 500 nsec wide pulse, and a several Joule, discharge pumped, KrCl laser operating at 222 nm. All of these devices are switched using thyratrons and are therefore capable of repetitive performance. The KrF and XeCl experiments were conducted with the same laser device operating with a conventional capacitor transfer excitation circuit for the KrF experiments but modified to operate with a pulser-sustainer discharge circuit using magnetic switching for the XeCl tests. The KrCl device is a 40 liter volume system built by Northrop and also operates with a magnetically switched discharge.

  15. New laser materials for laser diode pumping

    NASA Technical Reports Server (NTRS)

    Jenssen, H. P.

    1990-01-01

    The potential advantages of laser diode pumped solid state lasers are many with high overall efficiency being the most important. In order to realize these advantages, the solid state laser material needs to be optimized for diode laser pumping and for the particular application. In the case of the Nd laser, materials with a longer upper level radiative lifetime are desirable. This is because the laser diode is fundamentally a cw source, and to obtain high energy storage, a long integration time is necessary. Fluoride crystals are investigated as host materials for the Nd laser and also for IR laser transitions in other rare earths, such as the 2 micron Ho laser and the 3 micron Er laser. The approach is to investigate both known crystals, such as BaY2F8, as well as new crystals such as NaYF8. Emphasis is on the growth and spectroscopy of BaY2F8. These two efforts are parallel efforts. The growth effort is aimed at establishing conditions for obtaining large, high quality boules for laser samples. This requires numerous experimental growth runs; however, from these runs, samples suitable for spectroscopy become available.

  16. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Hwang, In Heon; Kim, Khong Hon; Stock, Larry V.

    1988-01-01

    A XeCl laser pumped iodine laser oscillator was developed which will be incorporated into the Master Oscillator Power Amplifier (MOPA) system. The developed XeCl laser produces output energy of about 60 mJ per pulse. The pulse duration was about 10 nsec. The kinetic model for the solar-pumped laser was refined and the algorithm for the calculation of a set of rate equations was improved to increase the accuracy and the efficiency of the calculation. The improved algorithm was applied to explain the existing experimental data taken from a flashlamp pumped iodine laser for three kinds of lasants, i-C3F7I, n-C4F9I, and t-C4F9I. Various solid laser materials were evaluated for solar-pumping. The materials studied were Nd:YAG, Nd:YLF, and Cr:Nd:GSGG crystals. The slope efficiency of 0.17 percent was measured for the Nd:YLF near the threshold pump intensity which was 211 solar constants (29W/sq cm). The threshold pump intensity of the Nd:YAG was measured to be 236 solar constants (32W/sq cm) and the near-threshold slope efficiency was 0.12 percent. True CW laser operation of Cr:Nd:GSGG was possible only at pump intensities less than or equal to 1,500 solar constants (203 W/sq cm). This fact was attributed to the high thermal focusing effect of the Cr:Nd:GSGG rod.

  17. Electron beam pumped semiconductor laser

    NASA Technical Reports Server (NTRS)

    Hug, William F. (Inventor); Reid, Ray D. (Inventor)

    2009-01-01

    Electron-beam-pumped semiconductor ultra-violet optical sources (ESUVOSs) are disclosed that use ballistic electron pumped wide bandgap semiconductor materials. The sources may produce incoherent radiation and take the form of electron-beam-pumped light emitting triodes (ELETs). The sources may produce coherent radiation and take the form of electron-beam-pumped laser triodes (ELTs). The ELTs may take the form of electron-beam-pumped vertical cavity surface emitting lasers (EVCSEL) or edge emitting electron-beam-pumped lasers (EEELs). The semiconductor medium may take the form of an aluminum gallium nitride alloy that has a mole fraction of aluminum selected to give a desired emission wavelength, diamond, or diamond-like carbon (DLC). The sources may be produced from discrete components that are assembled after their individual formation or they may be produced using batch MEMS-type or semiconductor-type processing techniques to build them up in a whole or partial monolithic manner, or combination thereof.

  18. Sunlight-Pumped Laser

    NASA Technical Reports Server (NTRS)

    Weaver, W. R. J.; Lee, J. H.

    1982-01-01

    Organic iodide gas is stimulated by portion of Sun's spectrum to emit laser light. Chopper forms pulses from beam of Xenon-Arc light. Chopper is only necessary to avoid buildup of laser-quenching species in sealed tube of present experiment. Perfluoropropyliodide lasing medium functions at temperatures of about 670 K, a fact that reduces cooling requirements in space.

  19. Compact and highly efficient laser pump cavity

    DOEpatents

    Chang, Jim J.; Bass, Isaac L.; Zapata, Luis E.

    1999-01-01

    A new, compact, side-pumped laser pump cavity design which uses non-conventional optics for injection of laser-diode light into a laser pump chamber includes a plurality of elongated light concentration channels. In one embodiment, the light concentration channels are compound parabolic concentrators (CPC) which have very small exit apertures so that light will not escape from the pumping chamber and will be multiply reflected through the laser rod. This new design effectively traps the pump radiation inside the pump chamber that encloses the laser rod. It enables more uniform laser pumping and highly effective recycle of pump radiation, leading to significantly improved laser performance. This new design also effectively widens the acceptable radiation wavelength of the diodes, resulting in a more reliable laser performance with lower cost.

  20. All solid-state mode-locked flashlamp pumped Nd:YAG laser system with selectable pulse duration

    NASA Astrophysics Data System (ADS)

    Kubecek, Vaclav; Diels, Jean-Claude; Stintz, Andreas; Jelinkova, Helena; Dombrovsky, Andrej; Cech, Miroslav

    2005-04-01

    All solid state mode-locked flashlamp pumped Nd:YAG laser system with selectable pulse duration was developed based on the oscillator where a single semiconductor structure containing a multiple-quantum-well was used as a saturable absorber for mode-locking, and energy limiter for passive negative feedback. Single pulse selection from various parts of extended 200 ns long Q-switched pulse train enables the changing of pulse duration before entering into three stages of laser amplifiers. Using of additional acousto-optic mode-locker, stability enhancement of the output pulses was obtained and the amplitude fluctuations were reduced below 5%. The exploitation of the solid state saturable absorber and limiter integrated in the single element improved significantly the long term characteristics of the laser system which can be therefore used for various applications as a satellite laser ranging, spectroscopy, or medicine.

  1. Algorithm for evaluation of temperature distribution of a vapor cell in a diode-pumped alkali laser system (part II).

    PubMed

    Han, Juhong; Wang, You; Cai, He; An, Guofei; Zhang, Wei; Xue, Liangping; Wang, Hongyuan; Zhou, Jie; Jiang, Zhigang; Gao, Ming

    2015-04-01

    With high efficiency and small thermally-induced effects in the near-infrared wavelength region, a diode-pumped alkali laser (DPAL) is regarded as combining the major advantages of solid-state lasers and gas-state lasers and obviating their main disadvantages at the same time. Studying the temperature distribution in the cross-section of an alkali-vapor cell is critical to realize high-powered DPAL systems for both static and flowing states. In this report, a theoretical algorithm has been built to investigate the features of a flowing-gas DPAL system by uniting procedures in kinetics, heat transfer, and fluid dynamic together. The thermal features and output characteristics have been simultaneously obtained for different gas velocities. The results have demonstrated the great potential of DPALs in the extremely high-powered laser operation. PMID:25968778

  2. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Hwang, In H.; Stock, Larry V.

    1988-01-01

    A XeCl laser which was developed earlier for an iodine laser oscillator was modified in order to increase the output pulse energy of XeCl laser so that the iodine laser output energy could be increased. The electrical circuit of the XeCl laser was changed from a simple capacitor discharge circuit of the XeCl laser to a Marx system. Because of this improvement the output energy from the XeCl laser was increased from 60 mj to 80 mj. Subsequently, iodine laser output energy was increased from 100 mj to 3 mj. On the other hand, the energy storage capability and amplification characteristics of the Vortek solar simulator-pumped amplifier was calculated expecting the calculated amplification factor is about 2 and the energy extraction efficiency is 26 percent due to the very low input energy density to the amplifier. As a result of an improved kinetic modeling for the iodine solar simulator pumped power amplifier, it is found that the I-2 along the axis of the tube affects seriously the gain profile. For the gas i-C3F7I at the higher pressures, the gain will decrease due to the I-2 as the pumping intensity increases, and at these higher pressures an increase in flow velocity will increase the gain.

  3. Systems efficiency and specific mass estimates for direct and indirect solar-pumped closed-cycle high-energy lasers in space

    NASA Technical Reports Server (NTRS)

    Monson, D. J.

    1978-01-01

    Based on expected advances in technology, the maximum system efficiency and minimum specific mass have been calculated for closed-cycle CO and CO2 electric-discharge lasers (EDL's) and a direct solar-pumped laser in space. The efficiency calculations take into account losses from excitation gas heating, ducting frictional and turning losses, and the compressor efficiency. The mass calculations include the power source, radiator, compressor, fluids, ducting, laser channel, optics, and heat exchanger for all of the systems; and in addition the power conditioner for the EDL's and a focusing mirror for the solar-pumped laser. The results show the major component masses in each system, show which is the lightest system, and provide the necessary criteria for solar-pumped lasers to be lighter than the EDL's. Finally, the masses are compared with results from other studies for a closed-cycle CO2 gasdynamic laser (GDL) and the proposed microwave satellite solar power station (SSPS).

  4. Ultra-stable flashlamp-pumped laser

    NASA Astrophysics Data System (ADS)

    Brachmann, A.; Clendenin, J.; Galetto, T.; Maruyama, T.; Sodja, J.; Turner, J.; Woods, M.

    2003-07-01

    We present the design and experimental results for the flashlamp-pumped Ti:Sapphire laser system used at the Stanford Linear Accelerator Center (SLAC). This laser system is used in conjunction with the Polarized Electron Source to generate polarized electron beams for fixed target experiments (e.g. the E-158 experiment). The unique capabilities such as high pulse-to-pulse stability, long pulse length and high repetition rate is discussed. Emphasis is placed on recent modifications of the laser system, which allow ultra-stable operation with 0.5% rms intensity jitter.

  5. Ho:YLF Laser Pumped by TM:Fiber Laser

    NASA Astrophysics Data System (ADS)

    Mizutani, Kohei; Ishii, Shoken; Itabe, Toshikazu; Asai, Kazuhiro; Sato, Atsushi

    2016-06-01

    A 2-micron Ho:YLF laser end-pumped by 1.94-micron Tm:fiber laser is described. A ring resonator of 3m length is adopted for the oscillator. The laser is a master oscillator and an amplifier system. It is operated at high repetition rate of 200-5000 Hz in room temperature. The laser outputs were about 9W in CW and more than 6W in Q-switched operation. This laser was developed to be used for wind and CO2 measurements.

  6. Scaling studies of solar pumped lasers

    NASA Technical Reports Server (NTRS)

    Christiansen, W. H.; Chang, J.

    1985-01-01

    A progress report of scaling studies of solar pumped lasers is presented. Conversion of blackbody radiation into laser light has been demonstrated in this study. Parametric studies of the variation of laser mixture composition and laser gas temperature were carried out for CO2 and N2O gases. Theoretical analysis and modeling of the system have been performed. Reasonable agreement between predictions in the parameter variation and the experimental results have been obtained. Almost 200 mW of laser output at 10.6 micron was achieved by placing a small sapphire laser tube inside an oven at 1500 K the tube was filled with CO2 laser gas mixture and cooled by longitudinal nitrogen gas flow.

  7. Scaling studies of solar pumped lasers

    NASA Astrophysics Data System (ADS)

    Christiansen, W. H.; Chang, J.

    1985-08-01

    A progress report of scaling studies of solar pumped lasers is presented. Conversion of blackbody radiation into laser light has been demonstrated in this study. Parametric studies of the variation of laser mixture composition and laser gas temperature were carried out for CO2 and N2O gases. Theoretical analysis and modeling of the system have been performed. Reasonable agreement between predictions in the parameter variation and the experimental results have been obtained. Almost 200 mW of laser output at 10.6 micron was achieved by placing a small sapphire laser tube inside an oven at 1500 K the tube was filled with CO2 laser gas mixture and cooled by longitudinal nitrogen gas flow.

  8. Research of the quenched dye lasers pumped by excimer lasers

    SciTech Connect

    Xue Shaolin; Lou Qihong

    1996-12-31

    In this paper, the quenched dye lasers pumped by XeCl and KrF excimer lasers were investigated theoretically and experimentally. Dye laser pulses with duration of 0.8 ns for XeCl laser pumping and 2 ns for KrF laser pumping were obtained. The dye Rhodamine 6G dissolved in methyl was used as the active medium in the quenched dye laser. When the pump laser was KrF and the active medium was Coumarin 498 the quenched dye laser emitted pulse with duration of about 2 ns. The characteristics of the quenched dye laser was also investigated in detail.

  9. APPLICATIONS OF LASERS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Laser system based on a commercial microwave oscillator with time compression of a microwave pump pulse

    NASA Astrophysics Data System (ADS)

    Arteev, M. S.; Vaulin, V. A.; Slinko, V. N.; Chumerin, P. Yu; Yushkov, Yu G.

    1992-06-01

    An analysis is made of the possibility of using a commercial microsecond microwave oscillator, supplemented by a device for time compression of microwave pulses, in pumping of industrial lasers with a high efficiency of conversion of the pump source energy into laser radiation. The results are reported of preliminary experiments on the commissioning of an excimer XeCl laser.

  10. Fusion pumped laser

    DOEpatents

    Pappas, Daniel S.

    1989-01-01

    Apparatus is provided for generating energy in the form of laser radiation. A tokamak fusion reactor is provided for generating a long, or continuous, pulse of high-energy neutrons. The tokamak design provides a temperature and a magnetic field which is effective to generate a neutron flux of at least 10.sup.15 neutrons/cm.sup.2.s. A conversion medium receives neutrons from the tokamak and converts the high-energy neutrons to an energy source with an intensity and an energy effective to excite a preselected lasing medium. The energy source typically comprises fission fragments, alpha particles, and radiation from a fission event. A lasing medium is provided which is responsive to the energy source to generate a population inversion which is effective to support laser oscillations for generating output radiation.

  11. High efficiency CW green-pumped alexandrite lasers

    NASA Astrophysics Data System (ADS)

    Kuper, J. W.; Brown, D. C.

    2006-02-01

    High power, CW and pulsed alexandrite lasers were produced by pumping the laser rod with a high quality diode pumped 532 nm laser sources. This pumping architecture provides stable performance with output power > 1.4 W at 767nm in the free running mode and 0.78W at 1000 Hz. An output of 80 mW at 375.5 nm was achieved at 500 Hz. This approach holds promise for the production of a scalable diode-pumped, tunable alexandrite laser systems operating in the near infrared (750 nm), and the ultraviolet (375 and 250 nm) spectral regions.

  12. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, K. S.

    1985-01-01

    This semiannual progress report covers the period from April 1, 1985 to Sept. 30, 1985 under NASA grant NAS1-441 entitled direct solar pumped iodine laser amplifier. During this period the parametric studies of the iodine laser oscillator pumped by a Vortek simulator was carried out before the amplifier studies. The amplifier studies are postponed to the extended period following completion of the parametric studies. In addition, the kinetic modeling of a solar pumped iodine laser amplifier, and the experimental work for a solar pumped dye laser amplifier are in progress. This report contains three parts: (1) the radiation characteristics of solar simulator and the parametric characteristics of photodissociation iodine laser continuously pumped by a Vortek solar simulator; (2) kinetic modeling of a solar pumped iodine laser amplifier; and (3) the study of the dye laser amplifier pumped by a Tamarack solar simulator.

  13. Prototype laser-diode-pumped solid state laser transmitters

    NASA Technical Reports Server (NTRS)

    Kane, Thomas J.; Cheng, Emily A. P.; Wallace, Richard W.

    1989-01-01

    Monolithic, diode-pumped Nd:YAG ring lasers can provide diffraction-limited, single-frequency, narrow-linewidth, tunable output which is adequate for use as a local oscillator in a coherent communication system. A laser was built which had a linewidth of about 2 kHz, a power of 5 milliwatts, and which was tunable over a range of 30 MHz in a few microseconds. This laser was phase-locked to a second, similar laser. This demonstrates that the powerful technique of heterodyne detection is possible with a diode-pumped laser used as the local oscillator. Laser diode pumping of monolithic Nd:YAG rings can lead to output powers of hundreds of milliwatts from a single laser. A laser was built with a single-mode output of 310 mW. Several lasers can be chained together to sum their power, while maintaining diffraction-limited, single frequency operation. This technique was demonstrated with two lasers, with a total output of 340 mW, and is expected to be practical for up to about ten lasers. Thus with lasers of 310 mW, output of up to 3 W is possible. The chaining technique, if properly engineered, results in redundancy. The technique of resonant external modulation and doubling is designed to efficiently convert the continuous wave, infrared output of our lasers into low duty-cycle pulsed green output. This technique was verified through both computer modeling and experimentation. Further work would be necessary to develop a deliverable system using this technique.

  14. Diode-pumped laser altimeter

    NASA Technical Reports Server (NTRS)

    Welford, D.; Isyanova, Y.

    1993-01-01

    TEM(sub 00)-mode output energies up to 22.5 mJ with 23 percent slope efficiencies were generated at 1.064 microns in a diode-laser pumped Nd:YAG laser using a transverse-pumping geometry. 1.32-micron performance was equally impressive at 10.2 mJ output energy with 15 percent slope efficiency. The same pumping geometry was successfully carried forward to several complex Q-switched laser resonator designs with no noticeable degradation of beam quality. Output beam profiles were consistently shown to have greater than 90 percent correlation with the ideal TEM(sub 00)-order Gaussian profile. A comparison study on pulse-reflection-mode (PRM), pulse-transmission-mode (PTM), and passive Q-switching techniques was undertaken. The PRM Q-switched laser generated 8.3 mJ pulses with durations as short as 10 ns. The PTM Q-switch laser generated 5 mJ pulses with durations as short as 5 ns. The passively Q-switched laser generated 5 mJ pulses with durations as short as 2.4 ns. Frequency doubling of both 1.064 microns and 1.32 microns with conversion efficiencies of 56 percent in lithium triborate and 10 percent in rubidium titanyl arsenate, respectively, was shown. Sum-frequency generation of the 1.064 microns and 1.32 microns radiations was demonstrated in KTP to generate 1.1 mJ of 0.589 micron output with 11.5 percent conversion efficiency.

  15. Photovoltaic pump systems

    NASA Astrophysics Data System (ADS)

    Klockgether, J.; Kiessling, K. P.

    1983-09-01

    Solar pump systems for the irrigation of fields and for water supply in regions with much sunshine are discussed. For surface water and sources with a hoisting depth of 12 m, a system with immersion pumps is used. For deep sources with larger hoisting depths, an underwater motor pump was developed. Both types of pump system meet the requirements of simple installation and manipulation, safe operation, maintenance free, and high efficiency reducing the number of solar cells needed.

  16. Possibilities of increasing the pumping efficiency of solid active medium laser generators by optimizing the pumping cavity profile

    NASA Astrophysics Data System (ADS)

    Dontu, O.; Ganatsios, S.; Alexandrescu, N.

    2008-03-01

    The paper presents some design elements concerning the optical pumping cavities of the laser generators with active solid medium, as well as the way of increasing their performance. We start from the fact that the laser cavity is a closed optical system, where the active laser medium and the pumping source are conjugated, in order to achieve a maximum concentration of the light flux of the pumping source towards the active medium. We discuss the simple elliptical section laser pumping cavities (with one pumping lamp) and triple elliptical (with three lamps), also presenting a series on calculus nomograms, very useful to those who design the laser generation optical pumping cavities.

  17. Femtosecond resolution timing jitter correction on a TW scale Ti:sapphire laser system for FEL pump-probe experiments

    NASA Astrophysics Data System (ADS)

    Csatari Divall, Marta; Mutter, Patrick; Divall, Edwin J.; Hauri, Christoph P.

    2015-11-01

    Intense ultrashort pulse lasers are used for fs resolution pumpprobe experiments more and more at large scale facilities, such as free electron lasers (FEL). Measurement of the arrival time of the laser pulses and stabilization to the machine or other sub-systems on the target, is crucial for high time-resolution measurements. In this work we report on a single shot, spectrally resolved, non-collinear cross-correlator with sub-fs resolution. With a feedback applied we keep the output of the TW class Ti:sapphire amplifier chain in time with the seed oscillator to ~3 fs RMS level for several hours. This is well below the typical pulse duration used at FELs and supports fs resolution pump-probe experiments. Short term jitter and long term timing drift measurements are presented. Applicability to other wavelengths and integration into the timing infrastructure of the FEL are also covered to show the full potential of the device.

  18. Blackbody-pumped CO2 laser experiment

    NASA Astrophysics Data System (ADS)

    Christiansen, W. H.; Insuik, R. J.

    1983-07-01

    Thermal radiation from a high temperature oven was used as an optical pump to achieve lasing from CO2 mixtures. Laser output as a function of blackbody temperature and gas conditions is described. This achievement represents the first blackbody cavity pumped laser and has potential for solar pumping. Previously announced in STAR as N83-10420

  19. Loop laser cavities with self-pumped phase-conjugate mirrors in low-gain active media for phase-locked multichannel laser systems

    SciTech Connect

    Basiev, Tasoltan T; Gavrilov, A V; Ershkov, M N; Smetanin, Sergei N; Fedin, Aleksandr V; Bel'kov, K A; Boreysho, A S; Lebedev, V F

    2011-03-31

    It is proved that lasers with different loop cavities with self-pumped phase-conjugate mirrors in low-gain active media can operate under injection of external laser radiation and can be used for the development of diode-pumped phase-locked multichannel neodymium laser systems operating both on the fundamental laser transition with the wavelength {lambda} = 1.06 {mu}m and on the transition with {lambda} = 1.34 {mu}m. The phase-conjugate oscillation thresholds in the case of injection of an external signal are determined for a multiloop cavity configuration and an increased number of active elements in the cavity. It is shown that phase-conjugate oscillation can occur even if the single-pass gain of the active element is as low as only {approx}2. Under high-power side diode pumping of a multiloop Nd:YAG laser, single-mode output radiation was achieved at {lambda} = 1.064 {mu}m with a pulse energy up to 0.75 J, a pulse repetition rate up to 25 Hz, an average power up to 18.3 W, and an efficiency up to 20%. In a multiloop Nd:YAG laser with three active elements in the cavity, single-mode radiation at {lambda} = 1.34 {mu}m was obtained with a pulse energy up to 0.96 J, a pulse repetition rate up to 10 Hz, and an average power up to 8.5 W. (control of laser radiation parameters)

  20. Direct nuclear-pumped laser amplifier

    NASA Technical Reports Server (NTRS)

    Jalufka, N. W.

    1981-01-01

    A (He-3)-Xe gas mixture, excited by the He-3(n,p)H-3 reaction, has been employed to amplify the output of a (He-3)Xe direct nuclear-pumped laser. Lasing occurred at the 2.63 micron line of XeI in the oscillator. The oscillator output was reflected through 180 deg and passed through the amplifier system. Power measurements of the oscillator output and the amplifier output show the laser power to be amplified by a factor of 3 for the (He-3)-Xe system. Amplification by a factor of 5 was obtained for a (He-3)-CO system.

  1. Theoretical studies of solar pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, Wynford L.

    1990-01-01

    One concept for collecting solar energy is to use large solar collectors and then use lasers as energy converters whose output beams act as transmission lines to deliver the energy to a destination. The efficiency of the process would be improved if the conversion could be done directly using solar pumped lasers, and the possibility of making such lasers is studied. There are many applications for such lasers, and these are examined. By including the applications first, the requirements for the lasers will be more evident. They are especially applicable to the Space program, and include cases where no other methods of delivering power seem possible. Using the lasers for conveying information and surveillance is also discussed. Many difficulties confront the designer of an efficient system for power conversion. These involve the nature of the solar spectrum, the method of absorbing the energy, the transfer of power into laser beams, and finally, the far field patterns of the beams. The requirements of the lasers are discussed. Specific laser configurations are discussed. The thrust is into gas laser systems, because for space applications, the laser could be large, and also the medium would be uniform and not subject to thermal stresses. Dye and solid lasers are treated briefly. For gas lasers, a chart of the various possibilities is shown, and the various families of gas lasers divided according to the mechanisms of absorbing solar radiation and of lasing. Several specific models are analyzed and evaluated. Overall conclusions for the program are summarized, and the performances of the lasers related to the requirements of various applications.

  2. Key techniques for space-based solar pumped semiconductor lasers

    NASA Astrophysics Data System (ADS)

    He, Yang; Xiong, Sheng-jun; Liu, Xiao-long; Han, Wei-hua

    2014-12-01

    In space, the absence of atmospheric turbulence, absorption, dispersion and aerosol factors on laser transmission. Therefore, space-based laser has important values in satellite communication, satellite attitude controlling, space debris clearing, and long distance energy transmission, etc. On the other hand, solar energy is a kind of clean and renewable resources, the average intensity of solar irradiation on the earth is 1353W/m2, and it is even higher in space. Therefore, the space-based solar pumped lasers has attracted much research in recent years, most research focuses on solar pumped solid state lasers and solar pumped fiber lasers. The two lasing principle is based on stimulated emission of the rare earth ions such as Nd, Yb, Cr. The rare earth ions absorb light only in narrow bands. This leads to inefficient absorption of the broad-band solar spectrum, and increases the system heating load, which make the system solar to laser power conversion efficiency very low. As a solar pumped semiconductor lasers could absorb all photons with energy greater than the bandgap. Thus, solar pumped semiconductor lasers could have considerably higher efficiencies than other solar pumped lasers. Besides, solar pumped semiconductor lasers has smaller volume chip, simpler structure and better heat dissipation, it can be mounted on a small satellite platform, can compose satellite array, which can greatly improve the output power of the system, and have flexible character. This paper summarizes the research progress of space-based solar pumped semiconductor lasers, analyses of the key technologies based on several application areas, including the processing of semiconductor chip, the design of small and efficient solar condenser, and the cooling system of lasers, etc. We conclude that the solar pumped vertical cavity surface-emitting semiconductor lasers will have a wide application prospects in the space.

  3. Recycle Rate in a Pulsed, Optically Pumped Rubidium Laser

    SciTech Connect

    Miller, Wooddy S.; Sulham, Clifford V.; Holtgrave, Jeremy C.; Perram, Glen P.

    2010-10-08

    A pulsed, optically pumped rubidium laser operating in analogy to the diode pumped alkali laser (DPAL) system at pump intensities as high as 750 kW/cm{sup 2} has been demonstrated with output energies of up to 13 {mu}J/pulse. Output energy is dramatically limited by spin-orbit relaxation rates under these high intensity pump conditions. More than 250 photons are available for every rubidium atom in the pumped volume, requiring a high number of cycles per atom during the 2-8 ns duration of the pump pulse. At 550 Torr of ethane, the spin-orbit relaxation rate is too slow to effectively utilize all the incident pump photons. Indeed, a linear dependence of output energy on pump pulse duration for fixed pump energy is demonstrated.

  4. High-efficiency side diode pumped breech mount laser ignition

    NASA Astrophysics Data System (ADS)

    Hardy, Christopher R.; Guo, Baoping; Myers, Michael J.; Myers, John D.

    2007-09-01

    Breech Mounted Lasers (BMLs) have been successfully used to demonstrate laser ignition of howitzer propellant charges including bag, stick, and the Modular Artillery Charge System (MACS). BMLs have been integrated and tested on many artillery systems, including the US Army's M109A6 Paladin, M198, M777 Light Weight, Crusader, and Non-Line-of-Sight Cannon (NLOS-C). Until now, these lasers have been relatively large and inefficient systems based on a flashlamp pumped Nd:YAG laser design. Modern vehicle platforms will require smaller, more efficient lasers that can operate under increased shock and vibration loads. Kigre's new DPSS (Diode Pumped Solid State) lasers appear to meet these requirements. In this work we provide an evaluation of HESP (High Efficiency Side Pumped) DPSS laser design and performance with regard to its application as a practical artillery laser ignition system.

  5. Lasers from fission. [nuclear pumping feasibility experiments

    NASA Technical Reports Server (NTRS)

    Schneider, R. T.; Thom, K.; Helmick, H. H.

    1975-01-01

    The feasibility of the nuclear pumping of lasers was demonstrated in three experiments conducted independently at three different laboratories. In this context nuclear pumping of lasers is understood to be the excitation of a laser by the kinetic energy of the fission fragments only. A description is given of research concerned with the use of nuclear energy for the excitation of gas lasers. Experimental work was supplemented by theoretical research. Attention is given to a nuclear pumped He-Xe laser, a nuclear pumped CO laser, and a neon-nitrogen laser pumped by alpha particles. Studies involving uranium hexafluoride admixture to laser media are discussed along with research on uranium hexafluoride-fueled reactors.

  6. Identification and properties of molecular systems of potential use in solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Micha, D. A.; Oehrn, N. Y.

    1985-01-01

    The concepts and computational tools of theortical chemistry are used to investigate molecular properties needed in direct solar-pumped lasers. Compounds of the type RR'CXY, with R and R' organic groups, and X and Y halide atoms were identified as likely candidates because of their highly enhanced absorption coefficients over compounds with a single halide atom. The use of a combination of vibrational excitation followed by electronic excitation to enhance quantum yields at certain wavelengths is indicated. A self-consistent eikonal approximation to state-to-state transitions was tested for CH3I and is useful for other problems involving electronic energy and charge transfer. An approach to calculate potential energy surfaces and transition dipoles was developed which is based on the generation of eigenstates of the nonrelativisitc Hamiltonian followed by incorporation of the spin-orbit coupling by configuration interaction.

  7. Solar-pumped gas laser development

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.

    1980-01-01

    A survey of gas properties through detailed kinetic models led to the identification of critical gas parameters for use in choosing appropriate gas combinations for solar pumped lasers. Broadband photoabsorption in the visible or near UV range is required to excite large volumes of gas and to insure good solar absorption efficiency. The photoexcitation density is independent of the absorption bandwidth. The state excited must be a metastable state which is not quenched by the parent gas. The emission bandwidth must be less than 10 A to insure lasing threshold over reasonable gain lengths. The system should show a high degree of chemical reversibility and an insensitivity to increasing temperature. Other properties such as good quantum efficiency and kinetic efficiency are also implied. Although photoexcitation of electronic vibrational transitions is considered as a possible system if the emission bands sufficiently narrow, it appears that photodissociation into atomic metastables is more likely to result in a successful solar pumped laser system.

  8. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, K. S.

    1986-01-01

    During this period the parametric studies of the iodine laser oscillator pumped by a Vortek simulator were carried out before amplifier studies. The amplifier studies are postponed to the extended period after completing the parametric studies. In addition, the kinetic modeling of a solar-pumped iodine laser amplifier, and the experimental work for a solar pumped dye laser amplifier are in progress. This report contains three parts: (1) a 10 W CW iodine laser pumped by a Vortek solar simulator; (2) kinetic modeling to predict the time to lasing threshold, lasing time, and energy output of solar-pumped iodine laser; and (3) the study of the dye laser amplifier pumped by a Tamarack solar simulator.

  9. Femtosecond resolution timing jitter correction on a TW scale Ti:sapphire laser system for FEL pump-probe experiments.

    PubMed

    Csatari Divall, Marta; Mutter, Patrick; Divall, Edwin J; Hauri, Christoph P

    2015-11-16

    Intense ultrashort pulse lasers are used for fs resolution pump-probe experiments more and more at large scale facilities, such as free electron lasers (FEL). Measurement of the arrival time of the laser pulses and stabilization to the machine or other sub-systems on the target, is crucial for high time-resolution measurements. In this work we report on a single shot, spectrally resolved, non-collinear cross-correlator with sub-fs resolution. With a feedback applied we keep the output of the TW class Ti:sapphire amplifier chain in time with the seed oscillator to ~3 fs RMS level for several hours. This is well below the typical pulse duration used at FELs and supports fs resolution pump-probe experiments. Short term jitter and long term timing drift measurements are presented. Applicability to other wavelengths and integration into the timing infrastructure of the FEL are also covered to show the full potential of the device. PMID:26698475

  10. Semiconductor Laser Diode Pumps for Inertial Fusion Energy Lasers

    SciTech Connect

    Deri, R J

    2011-01-03

    Solid-state lasers have been demonstrated as attractive drivers for inertial confinement fusion on the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) and at the Omega Facility at the Laboratory for Laser Energetics (LLE) in Rochester, NY. For power plant applications, these lasers must be pumped by semiconductor diode lasers to achieve the required laser system efficiency, repetition rate, and lifetime. Inertial fusion energy (IFE) power plants will require approximately 40-to-80 GW of peak pump power, and must operate efficiently and with high system availability for decades. These considerations lead to requirements on the efficiency, price, and production capacity of the semiconductor pump sources. This document provides a brief summary of these requirements, and how they can be met by a natural evolution of the current semiconductor laser industry. The detailed technical requirements described in this document flow down from a laser ampl9ifier design described elsewhere. In brief, laser amplifiers comprising multiple Nd:glass gain slabs are face-pumped by two planar diode arrays, each delivering 30 to 40 MW of peak power at 872 nm during a {approx} 200 {micro}s quasi-CW (QCW) pulse with a repetition rate in the range of 10 to 20 Hz. The baseline design of the diode array employs a 2D mosaic of submodules to facilitate manufacturing. As a baseline, they envision that each submodule is an array of vertically stacked, 1 cm wide, edge-emitting diode bars, an industry standard form factor. These stacks are mounted on a common backplane providing cooling and current drive. Stacks are conductively cooled to the backplane, to minimize both diode package cost and the number of fluid interconnects for improved reliability. While the baseline assessment in this document is based on edge-emitting devices, the amplifier design does not preclude future use of surface emitting diodes, which may offer appreciable future cost reductions and

  11. An investigation of a mathematical model of an optically pumped Ti(3+):Al2O3 laser system

    NASA Technical Reports Server (NTRS)

    Roberts, Lila F.

    1989-01-01

    During the last several years, solid state lasers were developed that have the potential for meeting rigorous performance requirements for space-based remote sensing of the atmosphere. In order to design a stable and efficient laser and to understand the effect on laser output of changes in the physical and design parameters, an understanding of the development of the dynamical processes of the laser is necessary. Typically, the dynamical processes in a laser system are investigated via rate equations describing the evolution of the occupancy in the electronic levels and of the photon density in the laser cavity. There are two approaches to this type of study. Most often, for the sake of simplicity, the spatial variations of the dynamic variables in the laser system are disregarded and the mathematical model consists of a system of first order nonlinear ordinary differential equations (ODE). The second approach is to take into account both spatial and temporal variations in the dynamic variables in the laser cavity. The resulting model consists of a first order semilinear system of partial differential equations (PDE). The model which was studied was studied was generic in the sense that it was a four-level laser system, but the parameters used in the numerical study were specific to Titanium-doped sapphire. For simplicity, a constant, spatially uniform pumping scheme was considered. In addition, a simplification of the model was made so that it treats a single lasing wavelength with a narrow bandwidth. The purpose was to investigate both versions of the mathematical model and to determine whether the numerical solutions are similar both qualitatively and quantitatively. The systems of ordinary differential equations were solved numerically using a Runge-Kutta-Fehlberg algorithm which was very efficient for typical values of the physical parameters. A numerical scheme, based on the Modified Euler method, for computing solutions to the system of partial differential

  12. Efficient pumping of inertial fusion energy lasers

    NASA Astrophysics Data System (ADS)

    Wessling, C.; Rübenach, O.; Hambücker, S.; Sinhoff, V.; Banerjeea, S.; Ertel, K.; Mason, P.

    2013-02-01

    Solid-state lasers have been demonstrated as attractive drivers for laser-plasma interaction and have presently been developed for various applications like inertial confinement fusion (ICF) [1], particle acceleration and intense X-ray generation [3]. Viable real world applications like power production at industrial scale will require high laser system efficiency, repetition rate and lifetime which are only possible with semiconductor diode pumping. The paper describes the work conducted with two 20 kW diode laser sources pumping an ytterbium:YAG laser amplifier. The set-up acts as a small scale prototype for the DiPOLE project [2]. This project aims to develop scalable gas cooled cryogenic multi-slab diode pumped solid state lasers capable of producing KJ pulse energy. A scale-down prototype is currently under development at the Central Laser Facility (CLF) designed to generate 10 J at 10 Hz. To secure an efficient pumping process the sources have to fulfill aside power requirement in the spectral and time domain, the claim for high homogenization and low divergence of the spatial and angular beam distribution as well as a minimization of losses within the optical path. The existing diode laser sources designed and built by INGENERIC deliver 20 kW pulsed power, concentrated on a plateau of FWHM dimension of 20 x 20 mm² with a homogeneity of more than 90 %. The center wavelength of 939.5 nm is controlled in a range of ± 0.1 nm. The time and area integrated spectrum of at least 76 % of the total energy is contained within a 6 nm wide wavelength band around the center wavelength. Repetition rates can be adjusted between 0.1 Hz up to 10 Hz with rise and fall times less than 50 μs and pulse durations from 0.2 ms to 1.2 ms. The paper describes the impact of different designs on the performance of pump sources and puts special emphasis on the influence of the optical components on efficiency and performance. In addition the influence of the measuring principle is

  13. Chemical oxygen-iodine laser with cryosorption vacuum pump

    NASA Astrophysics Data System (ADS)

    Vetrovec, John

    2000-05-01

    In a chemical oxygen-iodine laser (COIL), chemically prepared, gaseous gain medium at 3-10 Torr pressure is drawn through the laser cavity by vacuum suction. Multiple-stage vacuum pumps such as Roots blowers or steam ejectors are typically used to receive and compress the gas flowing from the laser and exhaust it to the atmosphere. The size and weight of such vacuum pumps present a significant challenge to engineering and packaging a transportable COIL system.

  14. A direct nuclear-pumped He-3-CO laser

    NASA Technical Reports Server (NTRS)

    Jalufka, N. W.; Hohl, F.

    1981-01-01

    Direct nuclear pumping of a low-temperature (150 K) He-3-CO laser has been achieved using the volumetric He-3(n,p)H-3 nuclear reaction. Lasing occurred on the vibrational bands of CO at about 5 microns. Effects of N2 on the system were investigated, as well as scaling of laser output with CO concentration, thermal neutron flux, and total pressure. This is the first volume-pumped, nuclear powered CO laser.

  15. Compact 36 kJ electron beam system for laser pumping

    SciTech Connect

    Schlitt, L.G.

    1981-05-31

    An electron beam machine consisting of six modules is being constructed for the 'B' amplifier of the RAPIER KrF laser system. Each module consists of a diode, a 5 ..cap omega.. positive charged water dielectric Blumlein pulse-forming line, and a five stage Marx generator. Separate 25 cm x 41 cm electron beams are formed in magnetically isolated diodes which when arranged in groups of three produce two nearly continuous 25 cm x 125 cm beams that enter the laser cell from opposite sides. The pulse-forming lines operate at 450 keV and produce 150 ns long pulses. The lines employ electrically triggered annular SF/sub 6/ output switches. The two concentric transmission lines of each pulse-forming line are charged in 1 ..mu..s through symmetric circuits to reduce diode prepulse voltage. The six modules together with the laser cell will occupy less than 15 m/sup 2/ of floor space.

  16. Micro-machining workstation for a diode pumped Nd:YAG high-brightness laser system

    NASA Astrophysics Data System (ADS)

    Kleijhorst, R. A.; Offerhaus, H. L.; Bant, P.

    1998-05-01

    A Nd:YAG micro-machining workstation that allows cutting on a scale of a few microns has been developed and operated. The system incorporates a telescope viewing system that allows control during the work and a software interface to translate AutoCad files. Some examples of the performance are given. With this setup we demonstrate the possibility of machining within a few microns with a Nd:YAG laser.

  17. NDT of fiber-reinforced composites with a new fiber-optic pump-probe laser-ultrasound system.

    PubMed

    Pelivanov, Ivan; Buma, Takashi; Xia, Jinjun; Wei, Chen-Wei; O'Donnell, Matthew

    2014-06-01

    Laser-ultrasonics is an attractive and powerful tool for the non-destructive testing and evaluation (NDT&E) of composite materials. Current systems for non-contact detection of ultrasound have relatively low sensitivity compared to contact peizotransducers. They are also expensive, difficult to adjust, and strongly influenced by environmental noise. Moreover, laser-ultrasound (LU) systems typically launch only about 50 firings per second, much slower than the kHz level pulse repetition rate of conventional systems. As demonstrated here, most of these drawbacks can be eliminated by combining a new generation of compact, inexpensive, high repetition rate nanosecond fiber lasers with new developments in fiber telecommunication optics and an optimally designed balanced probe beam detector. In particular, a modified fiber-optic balanced Sagnac interferometer is presented as part of a LU pump-probe system for NDT&E of aircraft composites. The performance of the all-optical system is demonstrated for a number of composite samples with different types and locations of inclusions. PMID:25302156

  18. Ho:YLF pumped HBr laser.

    PubMed

    Botha, L R; Bollig, C; Esser, M J D; Campbell, R N; Jacobs, C; Preussler, D R

    2009-10-26

    A Ho:YLF laser pumped HBr molecular laser was developed that produced up to 2.5 mJ of energy in the 4 micron wavelength region. The Ho:YLF laser was fiber pumped using a commercial Tm:fibre laser. The Ho:YLF laser was operated in a single longitudinal mode via injection seeding with a narrow band diode laser which in turn was locked to one of the HBr transitions. The behavior of the HBr laser was described using a rate equation mathematical model and this was solved numerically. Good agreement both qualitatively and quantitatively between the model and experimental results was obtained. PMID:19997290

  19. Design of multilamp nonimaging laser pump cavities

    SciTech Connect

    Kuppenheimer, J.D. Jr.

    1989-12-01

    A technique has been developed to design single laser rod, multiple flash lamp pump cavities that allow all of the energy generated by the lamp to pass through the laser rod before entering another lamp cavity. The effective lamp and rod perimeters are matched, guaranteeing maximal concentration and uniformity of pumping.

  20. Cladding For Transversely-Pumped Laser Rod

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.; Fan, Tso Yee

    1989-01-01

    Combination of suitable dimensioning and cladding of neodymium:yttrium aluminum garnet of similar solid-state laser provides for more efficient utilization of transversely-incident pump light from diode lasers. New design overcomes some of limitations of longitudinal- and older transverse-pumping concepts and promotes operation at higher output powers in TEM00 mode.

  1. Feasibility of solar-pumped dye lasers

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Kim, Kyung C.; Kim, Kyong H.

    1987-01-01

    Dye laser gains were measured at various pump-beam irradiances on a dye cell in order to evaluate the feasibility of solar pumping. Rhodamine 6G dye was considered as a candidate for the solar-pumped laser because of its high utilization of the solar spectrum and high quantum efficiency. Measurements show that a solar concentration of 20,000 is required to reach the threshold of the dye.

  2. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Hwang, In Heon

    1990-01-01

    The optimum conditions of a solar pumped iodine laser are found in this research for the case of a continuous wave operation and a pulsed operation. The optimum product of the pressure(p) inside the laser tube and the tube diameter(d) was pd=40 approx. 50 torr-cm on the contrary to the case of a high intensity flashlamp pumped iodine laser where the optimum value of the product is known to be pd=150 torr-cm. The pressure-diameter product is less than 1/3 of that of the high power iodine laser. During the research period, various laser materials were also studied for solar pumping. Among the laser materials, Nd:YAG is found to have the lowest laser threshold pumping intensity of about 200 solar constant. The Rhodamine 6G was also tested as the solar pumped laser material. The threshold pumping power was measured to be about 20,000 solar constant. The amplification experiment for a continuously pumped iodine laser amplifier was performed using Vortek solar simulator and the amplification factors were measured for single pass amplification and triple pass amplification of the 15 cm long amplifier tube. The amplification of 5 was obtained for the triple pass amplification.

  3. Diode pumped alkali vapor fiber laser

    DOEpatents

    Payne, Stephen A.; Beach, Raymond J.; Dawson, Jay W.; Krupke, William F.

    2007-10-23

    A method and apparatus is provided for producing near-diffraction-limited laser light, or amplifying near-diffraction-limited light, in diode pumped alkali vapor photonic-band-gap fiber lasers or amplifiers. Laser light is both substantially generated and propagated in an alkali gas instead of a solid, allowing the nonlinear and damage limitations of conventional solid core fibers to be circumvented. Alkali vapor is introduced into the center hole of a photonic-band-gap fiber, which can then be pumped with light from a pump laser and operated as an oscillator with a seed beam, or can be configured as an amplifier.

  4. Diode pumped alkali vapor fiber laser

    DOEpatents

    Payne, Stephen A.; Beach, Raymond J.; Dawson, Jay W.; Krupke, William F.

    2006-07-26

    A method and apparatus is provided for producing near-diffraction-limited laser light, or amplifying near-diffraction-limited light, in diode pumped alkali vapor photonic-band-gap fiber lasers or amplifiers. Laser light is both substantially generated and propagated in an alkali gas instead of a solid, allowing the nonlinear and damage limitations of conventional solid core fibers to be circumvented. Alkali vapor is introduced into the center hole of a photonic-band-gap fiber, which can then be pumped with light from a pump laser and operated as an oscillator with a seed beam, or can be configured as an amplifier.

  5. Solar-pumped solid-state lasers

    SciTech Connect

    Weksler, M.; Shwartz, J.

    1988-06-01

    Results are presented for direct solar pumping of a ND:YAG rod laser. Stable CW output of more than 60 W was obtained with a slope efficiency exceeding 2 percent. A compound parabolic concentrator, designed to increase the solar radiation coupled into the laser rod, was used in these experiments. The results are consistent with predictions based on a simple solar-pumped laser model, which is also presented. Using this model, it is shown that existing laser materials with broad-band absorption characteristics (e.g., alexandrite and Nd:Cr:GSGG) have a potential for better than 10 percent overall conversion efficiency when solar pumped.

  6. Instabilities in a three-level coherently pumped laser

    NASA Technical Reports Server (NTRS)

    Ryan, J. C.; Lawandy, N. M.

    1987-01-01

    A theory for a coherently pumped, homogeneously broadened laser is developed which predicts instability at excitations 1.6 times threshold. The system exhibits a period-doubling sequence, chaos, and a period-three window.

  7. GaAs laser diode pumped Nd:YAG laser

    NASA Technical Reports Server (NTRS)

    Conant, L. C.; Reno, C. W.

    1974-01-01

    A 1.5-mm by 3-cm neodymium-ion doped YAG laser rod has been side pumped using a GaAs laser diode array tuned to the 8680-A absorption line, achieving a multimode average output power of 120 mW for a total input power of 20 W to the final-stage laser diode drivers. The pumped arrangement was designed to take advantage of the high brightness of a conventional GaAs array as a linear source by introducing the pump light through a slit into a close-wrapped gold coated pump cavity. This cavity forms an integrating chamber for the pump light.

  8. Assignment of the /Li-7/2 optically pumped laser transitions pumped by Ar/+/ and Kr/+/ laser lines

    NASA Technical Reports Server (NTRS)

    Verma, K. K.; Stwalley, W. C.; Zemke, W. T.

    1981-01-01

    Welling and Wellegehausen (1977) have reported a list of Na2 and Li2 lines (belonging to B-X and A-X systems) which lase when vapors of these dimers are pumped with an Ar(+) or Kr(+) laser. A description is presented of a fluorescence study of the A-X system of the (Li-7)2 molecule excited by a Kr(+) laser (6471 A). The optically pumped laser lines are identified as P and R doublets in two different fluorescence series. The conditions which favor lasing action of these lines are pointed out. All but one of the known optically pumped laser lines of (Li-7)2 along with their assignments are presented in a table. For each pumping line, several additional wavelengths are listed which satisfy the condition for laser oscillations and which might well lase well under slightly improved conditions.

  9. Absorption heat pump system

    DOEpatents

    Grossman, Gershon

    1984-01-01

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  10. Absorption heat pump system

    DOEpatents

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  11. Grazing Incidence Pumping for High Efficiency X-ray Lasers

    SciTech Connect

    Dunn, J; Keenan, R; Shlyaptsev, V N

    2005-10-03

    Over the last decade, most laser-driven collisional excitation x-ray lasers have relied on the absorption of the pump energy incident at normal incidence to a pre-formed plasma. The main advantage is that the inversion can be created at various plasma regions in space and time where the amplification and ray propagation processes are best served. The main disadvantage is that different plasma regions regardless of the contribution to the inversion have to be pumped simultaneously in order to make the laser work. This leads to a loss of efficiency. The new scheme of grazing incidence pumping (GRIP) addresses this issue. In essence, a chosen electron density region of a pre-formed plasma column, produced by a longer pulse at normal incidence onto a slab target, is selectively pumped by focusing a short pulse of 100 fs-10 ps duration laser at a determined grazing incidence angle to the target surface. The exact angle is dependent on the pump wavelength and relates to refraction of the drive beam in the plasma. The controlled use of refraction of the pumping laser in the plasma results in several benefits: The pump laser path length is longer and there is an increase in the laser absorption in the gain region for creating a collisional Ni-like ion x-ray laser. There is also an inherent traveling wave, close to c, that increases the overall pumping efficiency. This can lead to a 3-30 times reduction in the pump energy for mid-Z, sub-20 nm lasers. We report several examples of this new x-ray laser on two different laser systems. The first demonstrates a 10 Hz x-ray laser operating at 18.9 nm pumped with a total of 150 mJ of 800 nm wavelength from a Ti:Sapphire laser. The second case is shown where the COMET laser is used both at 527 nm and 1054 nm wavelength to pump higher Z materials with the goal of extending the wavelength regime of tabletop x-ray lasers below 10 nm.

  12. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.

    1987-01-01

    This semiannual progress report covers the period from March 1, 1987 to September 30, 1987 under NASA grant NAG1-441 entitled 'Direct solar-pumped iodine laser amplifier'. During this period Nd:YAG and Nd:Cr:GSGG crystals have been tested for the solar-simulator pumped cw laser, and loss mechanisms of the laser output power in a flashlamp-pumped iodine laser also have been identified theoretically. It was observed that the threshold pump-beam intensities for both Nd:YAG and Nd:Cr:GSGG crystals were about 1000 solar constants, and the cw laser operation of the Nd:Cr:GSGG crystal was more difficult than that of the Nd:YAG crystal under the solar-simulator pumping. The possibility of the Nd:Cr:GSGG laser operation with a fast continuously chopped pumping was also observed. In addition, good agreement between the theoretical calculations and the experimental data on the loss mechanisms of a flashlamp-pumped iodine laser at various fill pressures and various lasants was achieved.

  13. Theoretcial studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, W. L.; Fong, Z. S.

    1984-01-01

    A method of pumping a COhZ laser by a hot cavity was demonstrated. The cavity, heated by solar radiation, should increase the efficiency of solar pumped lasers used for energy conversion. Kinetic modeling is used to examine the behavior of such a COhZ laser. The kinetic equations are solved numerically vs. time and, in addition, steady state solutions are obtained analytically. The effect of gas heating filling the lower laser level is included. The output power and laser efficiency are obtained as functions of black body temperature and gas ratios (COhZ-He-Ar) and pressures. The values are compared with experimental results.

  14. Diode laser-pumped solid-state lasers

    NASA Technical Reports Server (NTRS)

    Fan, Tso Yee; Byer, Robert L.

    1988-01-01

    Recently, interest in diode laser-pumped solid-state lasers has increased due to their advantages over flashlamp-pumped solid-state lasers. A historical overview is presented of semiconductor diode-pumped solid-state lasers beginning with work in the early 1960s and continuing through recent work on wavelength extension of these devices by laser operation on new transitions. Modeling of these devices by rate equations to obtain expressions for threshold, slope efficiency, and figures of merit is also given.

  15. Nuclear-pumped CO2 laser

    NASA Technical Reports Server (NTRS)

    Rowe, M.

    1979-01-01

    The He-3 (n,p)T reaction was examined as an energy source for a CO2 laser. For this purpose He-3 was added to a functioning CO2 electrically excited laser. Initially the laser was run electrically with 12 torr total pressure. The gas mixture was 1:1:8, CO2:N2:He. At zero reactor power, the laser was tested in place next to the core of the Georgia Tech. Research Reactor. After verification of laser action He-3 was added to the system. The He-3 partial pressures of 10 torr, 50 torr, and 300 torr were added in three separate reactor runs. Reactor power ranged from zero to 5 million watts, which corresponds to a peak flux of 10 to the 14th power/sq cm. At reactor powers greater than 10 kW, gain of up to 30 percent was shown. However, indications are this may be due to gamma excitation rather than caused by the He-3 (n,p)T reaction. These results do agree with the data of past CO2 nuclear pumped laser experiments.

  16. Continuous wave Cs diode pumped alkali laser pumped by single emitter narrowband laser diode.

    PubMed

    Zhdanov, B V; Venus, G; Smirnov, V; Glebov, L; Knize, R J

    2015-08-01

    This paper presents results of cooperative efforts on development of a continuous wave Cs diode pumped alkali laser with moderate output power, which can be considered as a prototype of the commercial device. The developed system operates at 895 nm with output power about 4 W and slope efficiency 28%. Measured turn on time of this system from the standby mode is about a minute. PMID:26329171

  17. Exploding conducting film laser pumping apparatus

    DOEpatents

    Ware, Kenneth D.; Jones, Claude R.

    1986-01-01

    Exploding conducting film laser optical pumping apparatus. The 342-nm molecular iodine and the 1.315-.mu.m atomic iodine lasers have been optically pumped by intense light from exploding-metal-film discharges. Brightness temperatures for the exploding-film discharges were approximately 25,000 K. Although lower output energies were achieved for such discharges when compared to exploding-wire techniques, the larger surface area and smaller inductance inherent in the exploding-film should lead to improved efficiency for optically-pumped gas lasers.

  18. Analysis of gain distribution in cladding-pumped thulium-doped fiber laser and optical feedback inhibition problem in fiber-bulk laser system

    NASA Astrophysics Data System (ADS)

    Ji, En-Cai; Liu, Qiang; Hu, Zhen-Yue; Gong, Ma-Li

    2015-10-01

    The steady-state gain distribution in cladding pumped thulium-doped fiber laser (TDFL) is analytically and numerically solved based on the rate equations including loss coefficients and cross relaxation effect. With the gain curve, a problem, which is named optical feedback inhibition (OFI) and always occurs in tandem TDFL-Ho:YAG laser system, is analyzed quantitatively. The actual characteristics of output spectra and power basically prove the conclusion of theoretical analysis. Then a simple mirror-deflected L-shaped cavity is employed to restrain the external feedback and simplify the structure of fiber-bulk Ho:YAG laser. Finally, 25 W of 2097-nm laser power and 51.2% of optical-to-optical conversion efficiency are obtained, and the beam quality factor is less than 1.43 obtained by knife-edge method. Project supported by the National Natural Science Foundation of China (Grant No. 61275146), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20120002110066), and the Special Program of the Co-construction with Beijing Municipal Government of China (Grant No. 20121000302).

  19. Direct pumping of ultrashort Ti:sapphire lasers by a frequency doubled diode laser

    NASA Astrophysics Data System (ADS)

    Müller, André; Jensen, Ole B.; Unterhuber, Angelika; Le, Tuan; Stingl, Andreas; Hasler, Karl-Heinz; Sumpf, Bernd; Erbert, Götz; Andersen, Peter E.; Petersen, Paul M.

    2011-12-01

    A simple and robust diode laser system emitting 1.28 W of green light suitable for pumping an ultrafast Ti:sapphire laser is presented. To classify our results, the diode laser is compared to a standard, commercially available diode pumped solid-state (DPSS) laser system pumping the same oscillator. When using our diode laser system, the optical conversion efficiencies from green to near-infrared light reduces to 75 % of the values achieved with the commercial pump laser. Despite this reduction the overall efficiency of the Ti:sapphire laser is still increased by a factor > 2 due to the superior electro-optical efficiency of the diode laser. Autocorrelation measurements show that pulse widths of less than 20 fs can be expected with an average power of 52 mW when using our laser. These results indicate the high potential of direct diode laser pumped Ti:sapphire lasers to be used in applications like retinal optical coherence tomography (OCT) or pumping of photonic crystal fibers for CARS (coherent anti-stokes Raman spectroscopy) microscopy.

  20. Flashlamp-pumped submicrosecond dye laser

    SciTech Connect

    Trusov, A.K.; Trusov, K.K.

    1985-02-01

    A laser flashlamp pumping system having an input energy of 330 J and a pulse duration of approx.230 nsec was developed experimentally and tests were made using a solution of rhodamine 6G under lasing conditions. The maximum lasing energy was 1.1 J, the efficiency was 0.33%, the angle of divergence of the beam at half-energy in a planar resonator was 1.2--1.3 mrad, and the illumination of an ethanol solution of rhodamine 6G halved the output energy when the intensity was 170 kJ/liter.

  1. Research on solar pumped liquid lasers

    NASA Technical Reports Server (NTRS)

    Schneider, R. T.; Kurzweg, U. H.; Cox, J. D.; Weinstein, N. H.

    1983-01-01

    A solar pumped liquid laser that can be scaled up to high power (10Mw CW) for space applications was developed. Liquid lasers have the inherent advantage over gases in that they provide much higher lasant densities and thus high power densities. Liquids also have inherent advantages over solids in that they have much higher damage thresholds and are much cheaper to produce for large scale applications. Among the liquid laser media that are potential candidates for solar pumping, the POC13:Nd(3+):ZrC14 liquid was chosen for its high intrinsic efficiency as well as its relatively good stability against decomposition due to protic contamination. The development and testing of the laser liquid and the development of a large solar concentrator to pump the laser was emphasized. The procedure to manufacture the laser liquid must include diagnostic tests of the solvent purity (from protic contamination) at various stages in the production process.

  2. AlGaAs diode pumped tunable chromium lasers

    DOEpatents

    Krupke, William F.; Payne, Stephen A.

    1992-01-01

    An all-solid-state laser system is disclosed wherein the laser is pumped in the longwave wing of the pump absorption band. By utilizing a laser material that will accept unusually high dopant concentrations without deleterious effects on the crystal lattice one is able to compensate for the decreased cross section in the wing of the absorption band, and the number of pump sources which can be used with such a material increases correspondingly. In a particular embodiment a chromium doped colquiriite-structure crystal such as Cr:LiSrAlF.sub.6 is the laser material. The invention avoids the problems associated with using AlGaInP diodes by doping the Cr:LiSrAlF.sub.6 heavily to enable efficient pumping in the longwave wing of the absorption band with more practical AlGaAs diodes.

  3. High efficiency >26 W diode end-pumped Alexandrite laser.

    PubMed

    Teppitaksak, Achaya; Minassian, Ara; Thomas, Gabrielle M; Damzen, Michael J

    2014-06-30

    We show for the first time that multi-ten Watt operation of an Alexandrite laser can be achieved with direct red diode-pumping and with high efficiency. An investigation of diode end-pumped Alexandrite rod lasers demonstrates continuous-wave output power in excess of 26W, more than an order of magnitude higher than previous diode end-pumping systems, and slope efficiency 49%, the highest reported for a diode-pumped Alexandrite laser. Wavelength tuning from 730 to 792nm is demonstrated using self-seeding feedback from an external grating. Q-switched laser operation based on polarization-switching to a lower gain axis of Alexandrite has produced ~mJ-pulse energy at 1kHz pulse rate in fundamental TEM(00) mode. PMID:24977887

  4. Deformation of partially pumped active mirrors for high average-power diode-pumped solid-state lasers.

    PubMed

    Albach, Daniel; LeTouzé, Geoffroy; Chanteloup, Jean-Christophe

    2011-04-25

    We discuss the deformation of a partially pumped active mirror amplifier as a free standing disk, as implemented in several laser systems. We rely on the Lucia laser project to experimentally evaluate the analytical and numerical deformation models. PMID:21643092

  5. Application of reactor-pumped lasers to power beaming

    SciTech Connect

    Repetti, T.E.

    1991-10-01

    Power beaming is the concept of centralized power generation and distribution to remote users via energy beams such as microwaves or laser beams. The power beaming community is presently performing technical evaluations of available lasers as part of the design process for developing terrestrial and space-based power beaming systems. This report describes the suitability of employing a nuclear reactor-pumped laser in a power beaming system. Although there are several technical issues to be resolved, the power beaming community currently believes that the AlGaAs solid-state laser is the primary candidate for power beaming because that laser meets the many design criteria for such a system and integrates well with the GaAs photodiode receiver array. After reviewing the history and physics of reactor-pumped lasers, the advantages of these lasers for power beaming are discussed, along with several technical issues which are currently facing reactor-pumped laser research. The overriding conclusion is that reactor-pumped laser technology is not presently developed to the point of being technially or economically competitive with more mature solid-state technologies for application to power beaming. 58 refs.

  6. Application of reactor-pumped lasers to power beaming

    NASA Astrophysics Data System (ADS)

    Repetti, T. E.

    1991-10-01

    Power beaming is the concept of centralized power generation and distribution to remote users via energy beams such as microwaves or laser beams. The power beaming community is presently performing technical evaluations of available lasers as part of the design process for developing terrestrial and space-based power beaming systems. This report describes the suitability of employing a nuclear reactor-pumped laser in a power beaming system. Although there are several technical issues to be resolved, the power beaming community currently believes that the AlGaAs solid-state laser is the primary candidate for power beaming because that laser meets the many design criteria for such a system and integrates well with the GaAs photodiode receiver array. After reviewing the history and physics of reactor-pumped lasers, the advantages of these lasers for power beaming are discussed, along with several technical issues which are currently facing reactor-pumped laser research. The overriding conclusion is that reactor-pumped laser technology is not presently developed to the point of being technically or economically competitive with more mature solid-state technologies for application to power beaming.

  7. Excited-state absorption of pump radiation as a loss mechanism in solid-state lasers

    SciTech Connect

    Kliewer, M.L.; Powell, R.C.

    1989-08-01

    The characteristics of optical pumping dynamics occuring in laser-pumped rare earth-doped, solid-state laser materials were investigated by using a tunable alexandrite laser to pump Y3Al5O12:Nd(3+) in an optical cavity. It was found that the slope efficiency of the Nd laser operation depends strongly on the wavelength of the pump laser. For pump wavelength resulting in low slope efficiencies, intense fluorescence emission is observed form the sample in the blue-green spectral region. This is attributed to the excited state absorption of pump photons which occurs during radiationless relaxation from the pump band to the metastable state. This type of process will be an important loss mechanism for monochromatic pumping of laser systems at specific pump wavelengths.

  8. Excited state absorption of pump radiation as a loss mechanism in solid-state lasers

    NASA Technical Reports Server (NTRS)

    Kliewer, Michael L.; Powell, Richard C.

    1989-01-01

    The characteristics of optical pumping dynamics in laser-pumped, rare-earth-doped, solid-state laser materials are investigated by using a tunable alexandrite laser to pump Y3Al5O12:Nd(3+) in an optical cavity. It is found that the slope efficiency of the Nd laser operation depends strongly on the wavelength of the pump laser. For pump wavelengths resulting in low slope efficiencies, intense fluorescence emission is observed from the sample in the blue-green spectral region. This is attributed to the excited-state absorption of pump photons which occurs during radiationless relaxation from the pump band to the metastable state. This type of process is an important loss mechanism for monochromatic pumping of laser systems at specific pump wavelengths.

  9. Excited state absorption of pump radiation as a loss mechanism in solid-state lasers

    SciTech Connect

    Kliewer, M.L.; Powell, R.C.

    1989-08-01

    The characteristics of optical pumping dynamics occurring in laser-pumped rare earth-doped, solid-state laser materials were investigated by using a tunable alexandrite laser to pump Y/sub 3/Al/sub 5/O/sub 12/:Nd/sup 3+/ in an optical cavity. It was found that the slope efficiency of the Nd laser operation depends strongly on the wavelength of the pump laser. For pump wavelengths resulting in low slope efficiencies, intense fluorescence emission is observed from the sample in the blue-green spectral region. This is attributed to the excited state absorption of pump photons which occurs during radiationless relaxation from the pump band to the metastable state. This type of process will be an important loss mechanism for monochromatic pumping of laser systems at specific pump wavelengths.

  10. Exploding conducting film laser pumping apparatus

    DOEpatents

    Ware, K.D.; Jones, C.R.

    1984-04-27

    The 342-nm molecular iodine and the 1.315-..mu..m atomic iodine lasers have been optically pumped by intense light from exploding-metal-film discharges. Brightness temperatures for the exploding-film discharges were approximately 25,000 K. Although lower output energies were achieved for such discharges when compared to exploding-wire techniques, the larger surface area and smaller inductance inherent in the exploding-film should lead to improved efficiency for optically-pumped gas lasers.

  11. Laser-induced quantum pumping in graphene

    SciTech Connect

    San-Jose, Pablo; Prada, Elsa; Kohler, Sigmund; Schomerus, Henning

    2012-10-08

    We investigate non-adiabatic electron pumping in graphene generated by laser irradiation with linear polarization parallel or perpendicular to the transport direction. Transport is dominated by the spatially asymmetric excitation of electrons from evanescent into propagating modes. For a laser with parallel polarization, the pumping response exhibits a subharmonic resonant enhancement which directly probes the Fermi energy; no such enhancement occurs for perpendicular polarization. The resonance mechanism relies on the chirality of charge carriers in graphene.

  12. Well-pump alignment system

    DOEpatents

    Drumheller, Douglas S.

    1998-01-01

    An improved well-pump for geothermal wells, an alignment system for a well-pump, and to a method for aligning a rotor and stator within a well-pump, wherein the well-pump has a whistle assembly formed at a bottom portion thereof, such that variations in the frequency of the whistle, indicating misalignment, may be monitored during pumping.

  13. Diode pumped Nd:YAG laser development

    NASA Technical Reports Server (NTRS)

    Reno, C. W.; Herzog, D. G.

    1976-01-01

    A low power Nd:YAG laser was constructed which employs GaAs injection lasers as a pump source. Power outputs of 125 mW TEM CW with the rod at 250 K and the pump at 180 K were achieved for 45 W input power to the pump source. Operation of the laser, with array and laser at a common heat sink temperature of 250 K, was inhibited by difficulties in constructing long-life GaAs LOC laser arrays. Tests verified pumping with output power of 20 to 30 mW with rod and pump at 250 K. Although life tests with single LOC GaAs diodes were somewhat encouraging (with single diodes operating as long as 9000 hours without degradation), failures of single diodes in arrays continue to occur, and 50 percent power is lost in a few hundred hours at 1 percent duty factor. Because of the large recent advances in the state of the art of CW room temperature AlGaAs diodes, their demonstrated lifetimes of greater than 5,000 hours, and their inherent advantages for this task, it is recommended that these sources be used for further CW YAG injection laser pumping work.

  14. A flashlamp pumped zig-zag slab dye laser

    NASA Astrophysics Data System (ADS)

    Dearth, J. J.; Vaughn, V. V.; McGowan, R. B.; Ehrlich, J.; Conrad, R. W.

    In the experiments reported here, the zig-zag principle is extended from solid slab to liquid dye lasers. A zig-zag dye laser is constructed, and the laser beam quality is observed for both straight-through and zig-zag paths. The zig-zag dye cell and its associated flashlamp pumping system are described, and thermally induced effects in the system are discussed.

  15. Research on solar pumped liquid lasers

    NASA Technical Reports Server (NTRS)

    Cox, J. D.; Kurzweg, U. H.; Weinstein, N. H.; Schneider, R. T.

    1985-01-01

    A solar pumped liquid laser that can be scaled up to high power (10 mW CW) for space applications was developed. Liquid lasers have the advantage over gases in that they provide much higher lasant densities and thus high-power densities. Liquids also have advantages over solids in that they have much higher damage thresholds and are much cheaper to produce for large scale applications. Among the liquid laser media that are potential candidates for solar pumping, the POC13: Nd sup 3+:ZrC14 liquid was chosen for its high intrinsic efficiency and its relatively good stability against decomposition due to protic contamination. The development of a manufacturing procedure and performance testing of the laser, liquid and the development of an inexpensive large solar concentrator to pump the laser are examined.

  16. Development of a lamp-pumped Cr:LiSAF laser operating at 20Hz for a terawatt CPA system

    NASA Astrophysics Data System (ADS)

    Samad, Ricardo E.; Nogueira, Gesse E. C.; Baldochi, Sonia L.; Vieira, Nilson D., Jr.

    2006-02-01

    We report here the development, construction and characterization of a flashlamp pumped Cr:LiSAF rod pumping cavity designed to minimize the thermal load on the crystal. The cavity is a close coupled one with 2 Xe lamps and absorptive filters between the lamps and the Cr:LiSAF rod, and is refrigerated with cooled water. A compact and stable (g I×g II=0.57) resonator was designed for lasers tests and gain medium characterization, and we expected to obtain operation at 20 Hz repetition rate. Nevertheless, the thermal load minimizing design was so successful that allowed laser operation up to 30 Hz with an average power of 20 W. When operating with a 10% transmission output coupler this laser exhibited an overall laser efficiency of 0.6% under 100 J electrical pumping, and a slope efficiency of 0.8%. Under these conditions, a maximum gain per pass of 1.5 was obtained, suitable for regenerative amplifiers. To increase the gain, the intracavity filters were substituted by glass plates, resulting in a gain per pass of 3.6, adequate for multipass amplifiers. In this configuration, and operating as a laser resonator, it showed a maximum overall efficiency of 2.81% under 88 J electrical pumping with a 25% transmission output coupler, and maximum output power of 18 W at 8 Hz. A study of the thermal load on the crystal was conducted by observation of the upper laser level lifetime, and we concluded that there are no noticeable accumulated thermal effects on the Cr:LiSAF emission.

  17. An experimental investigation of 235 sub UF sub 6 fission produced plasmas. [gas handling system for use with nuclear pumped laser experiments

    NASA Technical Reports Server (NTRS)

    Miley, G. H.

    1981-01-01

    A gas handling system capable of use with uranium fluoride was designed and constructed for use with nuclear pumped laser experiments using the TRIGA research reactor. By employing careful design and temperature controls, the UF6 can be first transported into the irradiation chamber, and then, at the conclusion of the experiment, returned to gas cylinders. The design of the system is described. Operating procedures for the UF6 and gas handling systems are included.

  18. Frequency stabilization of diode-laser-pumped solid state lasers

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1988-01-01

    The goal of the NASA Sunlite program is to fly two diode-laser-pumped solid-state lasers on the space shuttle and while doing so to perform a measurement of their frequency stability and temporal coherence. These measurements will be made by combining the outputs of the two lasers on an optical radiation detector and spectrally analyzing the beat note. Diode-laser-pumped solid-state lasers have several characteristics that will make them useful in space borne experiments. First, this laser has high electrical efficiency. Second, it is of a technology that enables scaling to higher powers in the future. Third, the laser can be made extremely reliable, which is crucial for many space based applications. Fourth, they are frequency and amplitude stable and have high temporal coherence. Diode-laser-pumped solid-state lasers are inherently efficient. Recent results have shown 59 percent slope efficiency for a diode-laser-pumped solid-state laser. As for reliability, the laser proposed should be capable of continuous operation. This is possible because the diode lasers can be remote from the solid state gain medium by coupling through optical fibers. Diode lasers are constructed with optical detectors for monitoring their output power built into their mounting case. A computer can actively monitor the output of each diode laser. If it sees any variation in the output power that might indicate a problem, the computer can turn off that diode laser and turn on a backup diode laser. As for stability requirements, it is now generally believed that any laser can be stabilized if the laser has a frequency actuator capable of tuning the laser frequency as far as it is likely to drift in a measurement time.

  19. Theoretical and experimental studies of optically pumped molecular gas lasers

    NASA Astrophysics Data System (ADS)

    Ratanavis, Amarin

    Optically pumped molecular gas lasers based on vibrational-rotational transitions in the infrared spectral region were studied experimentally and theoretically. A model was developed to predict the performance of such lasers and explore their potentials for energy and power scaling. This rate equation model was applied to explore the performance of a second-overtone (pulsed) and a first-overtone (CW) pumped HBr laser. Experimental improvements concerning temperature spectral tuning and frequency stabilization of a Nd:YAG laser that pumped HBr were accomplished. Lasing at 4 microns was demonstrated from such a system. We identified acetylene and hydrogen cyanide as potential laser gases that can be pumped with lasers emitting in the attractive telecommunication C band region at about 1.5 microns. Estimations and fluorescence measurements suggest the possibility of lasing in the 3 micron region. Lasing was demonstrated for the first time with a 5 ns pump pulse from an optical parametric oscillator using traditional cavities. The first gas filled hollow fiber laser based on population inversion was demonstrated with C2H2 and emission in the 3 micron region was observed. An analytical model indicates the possibility of CW lasing with small Stokes shift in both C2H 2 and HCN.

  20. Semiconductor disk laser-pumped subpicosecond holmium fibre laser

    SciTech Connect

    Chamorovskiy, A Yu; Marakulin, A V; Leinonen, T; Kurkov, Andrei S; Okhotnikov, Oleg G

    2012-01-31

    The first passively mode-locked holmium fibre laser has been demonstrated, with a semiconductor saturable absorber mirror (SESAM) as a mode locker. Semiconductor disk lasers have been used for the first time to pump holmium fibre lasers. We obtained 830-fs pulses at a repetition rate of 34 MHz with an average output power of 6.6 mW.

  1. Pulsed differential pumping system

    SciTech Connect

    Antipov, G.N.; Bagautdinov, F.A.; Rybalov, S.V.

    1985-06-01

    A pulsed differential pumping system is described for extracting an electron beam from a shaping region at a pressure of 10/sup -5/ torr into a volume with a pressure of 10-100 torr. A fast valve is used with appropriate geometrical parameters to reduce the length of the outlet channel considerable while increasing its diameter. Test results are given. The pumping system has two sections which communicate one with the other and with the volume at the elevated pressure which is produced by gasdynamic nozzles.

  2. LaRC results on nuclear pumped noble gas lasers

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J.

    1979-01-01

    The recent experiment and theoretical results obtained for noble gas nuclear laser systems are presented. It is shown that the noble gas lasers are among the easiest systems to pump by nuclear excitation and as a result, all of the noble gases except He have lased under nuclear excitation. The noble gas systems are not ideal for high-power applications but they do give valuable insight into the operation and pumping mechanisms associated with nuclear lasers. At present, the Ar-Xe system is the best noble gas candidate for (U-235)F6 pumping. It appears that the quenching of Ar-Xe lasing is a result of the fluorine and not the uranium or fission fragments themselves. Thus, to achieve lasing with UF6, a fluorine compatible system must be found.

  3. Stable, red laser pumped, multi-kilohertz Alexandrite laser

    NASA Astrophysics Data System (ADS)

    Ogilvy, Hamish; Withford, Michael J.; Piper, James A.

    2006-04-01

    Operation of a miniature Alexandrite laser pulse-pumped at 671 nm by a Q-switched, frequency-doubled, diode-pumped Nd:GdVO4 laser is reported. Average power output ∼150 mW at 765 nm with optical-to-optical slope efficiencies of 28% has been demonstrated for gain-switched operation of the Alexandrite laser at 80 kHz. Q-switched pump-pulse stacking has been used to reduce output pulse width by a factor of 6 and increase peak power by a factor of 38 over gain-switched operation.

  4. Passively Q-switched side pumped monolithic ring laser

    NASA Technical Reports Server (NTRS)

    Li, Steven X. (Inventor)

    2012-01-01

    Disclosed herein are systems and methods for generating a side-pumped passively Q-switched non-planar ring oscillator. The method introduces a laser into a cavity of a crystal, the cavity having a round-trip path formed by a reflection at a dielectrically coated front surface, a first internal reflection at a first side surface of the crystal at a non-orthogonal angle with the front, a second internal reflection at a top surface of the crystal, and a third internal reflection at a second side surface of the crystal at a non-orthogonal angle with the front. The method side pumps the laser at the top or bottom surface with a side pump diode array beam and generates an output laser emanating at a location on the front surface. The design can include additional internal reflections to increase interaction with the side pump. Waste heat may be removed by mounting the crystal to a heatsink.

  5. Investigation of the pump wavelength influence on pulsed laser pumped Alexandrite lasers

    NASA Astrophysics Data System (ADS)

    Ogilvy, H.; Withford, M. J.; Mildren, R. P.; Piper, J. A.

    2005-09-01

    Recent theoretical modelling and experimental results have shown that excess lattice phonon energy created dur ing the non-radiative energy transfer from the 4T2 pump manifold to the 2E storage level in Alexandrite when pumped with wavelengths shorter than ˜645 nm causes chaotic lasing output. Shorter pump wavelengths have also been associated with increased non-radiative energy decay and reduced laser efficiency. We report studies of fluorescence emission spectra of Alexandrite illuminated at a range of wavelengths from green to red, which demonstrate reduced fluorescence yield for shorter pump wavelengths at elevated crystal temperatures. Investigations of pulsed laser pumping of Alexandrite over the same spectral range demonstrated reduced pump threshold energy for longer pump wavelengths. High repetition rate pulsed pumping of Alexandrite at 532, 578 and 671 nm showed stable and efficient laser performance was only achieved for red pumping at 671 nm. These results support the theoretical model and demonstrate the potential for scalable, red laser pumped, all-solid-state Alexandrite lasers.

  6. High average power diode pumped solid state lasers for CALIOPE

    SciTech Connect

    Comaskey, B.; Halpin, J.; Moran, B.

    1994-07-01

    Diode pumping of solid state media offers the opportunity for very low maintenance, high efficiency, and compact laser systems. For remote sensing, such lasers may be used to pump tunable non-linear sources, or if tunable themselves, act directly or through harmonic crystals as the probe. The needs of long range remote sensing missions require laser performance in the several watts to kilowatts range. At these power performance levels, more advanced thermal management technologies are required for the diode pumps. The solid state laser design must now address a variety of issues arising from the thermal loads, including fracture limits, induced lensing and aberrations, induced birefringence, and laser cavity optical component performance degradation with average power loading. In order to highlight the design trade-offs involved in addressing the above issues, a variety of existing average power laser systems are briefly described. Included are two systems based on Spectra Diode Laboratory`s water impingement cooled diode packages: a two times diffraction limited, 200 watt average power, 200 Hz multi-rod laser/amplifier by Fibertek, and TRW`s 100 watt, 100 Hz, phase conjugated amplifier. The authors also present two laser systems built at Lawrence Livermore National Laboratory (LLNL) based on their more aggressive diode bar cooling package, which uses microchannel cooler technology capable of 100% duty factor operation. They then present the design of LLNL`s first generation OPO pump laser for remote sensing. This system is specified to run at 100 Hz, 20 nsec pulses each with 300 mJ, less than two times diffraction limited, and with a stable single longitudinal mode. The performance of the first testbed version will be presented. The authors conclude with directions their group is pursuing to advance average power lasers. This includes average power electro-optics, low heat load lasing media, and heat capacity lasers.

  7. COMPUTER MODEL OF TEMPERATURE DISTRIBUTION IN OPTICALLY PUMPED LASER RODS

    NASA Technical Reports Server (NTRS)

    Farrukh, U. O.

    1994-01-01

    Managing the thermal energy that accumulates within a solid-state laser material under active pumping is of critical importance in the design of laser systems. Earlier models that calculated the temperature distribution in laser rods were single dimensional and assumed laser rods of infinite length. This program presents a new model which solves the temperature distribution problem for finite dimensional laser rods and calculates both the radial and axial components of temperature distribution in these rods. The modeled rod is either side-pumped or end-pumped by a continuous or a single pulse pump beam. (At the present time, the model cannot handle a multiple pulsed pump source.) The optical axis is assumed to be along the axis of the rod. The program also assumes that it is possible to cool different surfaces of the rod at different rates. The user defines the laser rod material characteristics, determines the types of cooling and pumping to be modeled, and selects the time frame desired via the input file. The program contains several self checking schemes to prevent overwriting memory blocks and to provide simple tracing of information in case of trouble. Output for the program consists of 1) an echo of the input file, 2) diffusion properties, radius and length, and time for each data block, 3) the radial increments from the center of the laser rod to the outer edge of the laser rod, and 4) the axial increments from the front of the laser rod to the other end of the rod. This program was written in Microsoft FORTRAN77 and implemented on a Tandon AT with a 287 math coprocessor. The program can also run on a VAX 750 mini-computer. It has a memory requirement of about 147 KB and was developed in 1989.

  8. Fiber laser pumped high energy cryogenically cooled Ho:YLF laser

    NASA Astrophysics Data System (ADS)

    Lippert, Espen; Fonnum, Helge; Stenersen, Knut

    2012-09-01

    In this paper we report on a high energy, low repetition rate 2-micron-laser, with high conversion efficiency in terms of output energy per pump power. The laser consists of a Ho3+-doped LiYF4 (YLF) crystal cooled to cryogenic temperatures in an unstable resonator, pumped by a thulium fiber laser. The cooling to 77 K makes Ho:YLF a quasi four level laser system, which greatly enhances the extraction efficiency. We achieved 356 mJ in Q-switched operation at 1 Hz PRF when pumping the laser with 58 W for 36 ms. The high beam quality from the fiber laser and the use of an unstable resonator with a graded reflectivity mirror (GRM) resulted in a high quality laser beam with a M2-value of 1.3.

  9. Influence of the pump-to-laser beam overlap on the performance of optically pumped cesium vapor laser.

    PubMed

    Cohen, Tom; Lebiush, Eyal; Auslender, Ilya; Barmashenko, Boris D; Rosenwaks, Salman

    2016-06-27

    Experimental and theoretical study of the influence of the pump-to-laser beam overlap, a crucial parameter for optimization of optically pumped alkali atom lasers, is reported for Ti:Sapphire pumped Cs laser. Maximum laser power > 370 mW with an optical-to-optical efficiency of 43% and slope efficiency ~55% was obtained. The dependence of the lasing power on the pump power was found for different pump beam radii at constant laser beam radius. Non monotonic dependence of the laser power (optimized over the temperature of the Cs cell) on the pump beam radius was observed with a maximum achieved at the ratio ~0.7 between the pump and laser beam radii. The optimal temperature decreased with increasing pump beam radius. A simple optical model of the laser, where Gaussian spatial shapes of the pump and laser intensities in any cross section of the beams were assumed, was compared to the experiments. Good agreement was obtained between the measured and calculated dependence of the laser power on the pump power at different pump beam radii and also of the laser power, threshold pump power and optimal temperature on the pump beam radius. The model does not use empirical parameters such as mode overlap efficiency and can be applied to different Ti:Sapphire and diode pumped alkali lasers with arbitrary spatial distributions of the pump and laser beam widths. PMID:27410591

  10. LED pumped polymer laser sensor for explosives

    PubMed Central

    Wang, Yue; Morawska, Paulina O; Kanibolotsky, Alexander L; Skabara, Peter J; Turnbull, Graham A; Samuel, Ifor D W

    2013-01-01

    A very compact explosive vapor sensor is demonstrated based on a distributed feedback polymer laser pumped by a commercial InGaN light-emitting diode. The laser shows a two-stage turn on of the laser emission, for pulsed drive currents above 15.7 A. The ‘double-threshold’ phenomenon is attributed to the slow rise of the ∼30 ns duration LED pump pulses. The laser emits a 533 nm pulsed output beam of ∼10 ns duration perpendicular to the polymer film. When exposed to nitroaromatic model explosive vapors at ∼8 ppb concentration, the laser shows a 46% change in the surface-emitted output under optimized LED excitation. PMID:25821526

  11. Optically pumped Na/sub 2/ laser

    SciTech Connect

    Kanorskii, S.I.; Kaslin, V.M.; Yakushev, O.F.

    1980-10-01

    A pulsed copper vapor laser emitting the 578.2 nm line was used as the pump source in achieving stimulated emission as a result of the electronic A/sup 1/..sigma../sup +//sub u/ to X/sup 1/..sigma../sup +//sub g/ transitions in the Na/sub 2/ molecule in the spectral range 0.765 to 0.804 ..mu... The average power of all the emission lines was 10 mW when the pulsed pump power was 150 W and the efficiency of conversion of the optical pump energy was about 3%. The pulse repetition frequency was 3.3 kHz. Violet diffuse radiation of the Na/sub 2/ molecules, generated by pumping with the copper vapor laser, was observed. The superradiance regime was found for some of the lines.

  12. Solar pumped lasers and their applications

    NASA Astrophysics Data System (ADS)

    Lee, Ja H.

    Since 1980, NASA has been pursuing high power solar lasers as part of the space power beaming program. Materials in liquid, solid, and gas phases have been evaluated against the requirements for solar pumping. Two basic characteristics of solar insolation, namely its diffuse irradiance and 5800 K blackbody-like spectrum, impose rather stringent requirements for laser excitation. However, meeting these requirements is not insurmountable as solar thermal energy technology has progressed today, and taking advantage of solar pumping lasers is becoming increasingly attractive. The high density photons of concentrated solar energy have been used for mainly electric power generation and thermal processing of materials by the DOE Solar Thermal Technologies Program. However, the photons can interact with materials through many other direct kinetic paths, and applications of the concentrated photons could be extended to processes requiring photolysis, photosynthesis, and photoexcitation. The use of solar pumped lasers on Earth seems constrained by economics and sociopolitics. Therefore, prospective applications may be limited to those that require use of quantum effects and coherency of the laser in order to generate extremely high value products and services when conventional and inexpensive means are ineffective or impossible. The new applications already proposed for concentrated solar photons, such as destruction of hazardous waste, production of renewable fuel, production of fertilizer, and air/water pollution controls, may benefit from the use of inexpensive solar pumped laser matched with the photochemical kinetics of these processes.

  13. Solar pumped continuous wave carbon dioxide laser

    NASA Technical Reports Server (NTRS)

    Yesil, O.; Christiansen, W. H.

    1978-01-01

    In an effort to demonstrate the feasibility of a solar pumped laser concept, gain has been measured in a CO2-He laser medium optically pumped by blackbody radiation. Various gas mixtures of CO2 and He have been pumped by blackbody radiation emitted from an electrically heated oven. Using a CO2 laser as a probe, an optical gain coefficient of 1.8 x 10 to the -3rd/cm has been measured at 10.6 microns for a 9:1 CO2-He mixture at an oven temperature of about 1500 K, a gas temperature of about 400 K and a pressure of about 1 torr. This corresponds to a small signal gain coefficient when allowance is made for saturation effects due to the probe beam, in reasonable agreement with a theoretical value.

  14. Diode pumped solid state kilohertz disk laser system for time-resolved combustion diagnostics under microgravity at the drop tower Bremen

    NASA Astrophysics Data System (ADS)

    Wagner, Volker; Paa, Wolfgang; Triebel, Wolfgang; Eigenbrod, Christian; Klinkov, Konstantin; Larionov, Mikhail; Giesen, Adolf; Stolzenburg, Christian

    2014-03-01

    We describe a specially designed diode pumped solid state laser system based on the disk laser architecture for combustion diagnostics under microgravity (μg) conditions at the drop tower in Bremen. The two-stage oscillator-amplifier-system provides an excellent beam profile (TEM00) at narrowband operation (Δλ < 1 pm) and is tunable from 1018 nm to 1052 nm. The laser repetition rate of up to 4 kHz at pulse durations of 10 ns enables the tracking of processes on a millisecond time scale. Depending on the specific issue it is possible to convert the output radiation up to the fourth harmonic around 257 nm. The very compact laser system is integrated in a slightly modified drop capsule and withstands decelerations of up to 50 g (>11 ms). At first the concept of the two-stage disk laser is briefly explained, followed by a detailed description of the disk laser adaption to the drop tower requirements with special focus on the intended use under μg conditions. In order to demonstrate the capabilities of the capsule laser as a tool for μg combustion diagnostics, we finally present an investigation of the precursor-reactions before the droplet ignition using 2D imaging of the Laser Induced Fluorescence of formaldehyde.

  15. Diode pumped solid state kilohertz disk laser system for time-resolved combustion diagnostics under microgravity at the drop tower Bremen.

    PubMed

    Wagner, Volker; Paa, Wolfgang; Triebel, Wolfgang; Eigenbrod, Christian; Klinkov, Konstantin; Larionov, Mikhail; Giesen, Adolf; Stolzenburg, Christian

    2014-03-01

    We describe a specially designed diode pumped solid state laser system based on the disk laser architecture for combustion diagnostics under microgravity (μg) conditions at the drop tower in Bremen. The two-stage oscillator-amplifier-system provides an excellent beam profile (TEM00) at narrowband operation (Δλ < 1 pm) and is tunable from 1018 nm to 1052 nm. The laser repetition rate of up to 4 kHz at pulse durations of 10 ns enables the tracking of processes on a millisecond time scale. Depending on the specific issue it is possible to convert the output radiation up to the fourth harmonic around 257 nm. The very compact laser system is integrated in a slightly modified drop capsule and withstands decelerations of up to 50 g (>11 ms). At first the concept of the two-stage disk laser is briefly explained, followed by a detailed description of the disk laser adaption to the drop tower requirements with special focus on the intended use under μg conditions. In order to demonstrate the capabilities of the capsule laser as a tool for μg combustion diagnostics, we finally present an investigation of the precursor-reactions before the droplet ignition using 2D imaging of the Laser Induced Fluorescence of formaldehyde. PMID:24689563

  16. Diode pumped solid state kilohertz disk laser system for time-resolved combustion diagnostics under microgravity at the drop tower Bremen

    SciTech Connect

    Wagner, Volker; Paa, Wolfgang; Triebel, Wolfgang; Eigenbrod, Christian; Klinkov, Konstantin; Larionov, Mikhail; Giesen, Adolf; Stolzenburg, Christian

    2014-03-15

    We describe a specially designed diode pumped solid state laser system based on the disk laser architecture for combustion diagnostics under microgravity (μg) conditions at the drop tower in Bremen. The two-stage oscillator-amplifier-system provides an excellent beam profile (TEM{sub 00}) at narrowband operation (Δλ < 1 pm) and is tunable from 1018 nm to 1052 nm. The laser repetition rate of up to 4 kHz at pulse durations of 10 ns enables the tracking of processes on a millisecond time scale. Depending on the specific issue it is possible to convert the output radiation up to the fourth harmonic around 257 nm. The very compact laser system is integrated in a slightly modified drop capsule and withstands decelerations of up to 50 g (>11 ms). At first the concept of the two-stage disk laser is briefly explained, followed by a detailed description of the disk laser adaption to the drop tower requirements with special focus on the intended use under μg conditions. In order to demonstrate the capabilities of the capsule laser as a tool for μg combustion diagnostics, we finally present an investigation of the precursor-reactions before the droplet ignition using 2D imaging of the Laser Induced Fluorescence of formaldehyde.

  17. Power scaling of a wavelength-narrowed diode laser system for pumping alkali vapors

    NASA Astrophysics Data System (ADS)

    Hersman, F. W.; Distelbrink, J. H.; Ketel, J.; Wilson, J.; Watt, D. W.

    2016-03-01

    We report a method for locking the output wavelength and reducing the spectral linewidth of diode lasers by feeding back light to the emitters from a wavelength selective external optical cavity. Ten years ago our team developed a stepped-mirror that allowed a single external cavity to lock the wavelength of a stack of diode array bars by equalizing path lengths between each emitter and the grating. Here we report combining one such step-mirror external cavity with an array of power dividers, each sending a portion of this feedback power to a separate diode array bar stack.

  18. Threshold pump power of a solar-pumped dye laser

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Kim, Kyung C.; Kim, Kyong H.

    1988-01-01

    Threshold solar power for dye laser pumping has been determined by measuring the gain of a rhodamine 6G dye laser amplifier at various solar-simulated irradiances on an amplifier cell. The measured threshold was 20,000 solar constants (2.7 kW/sq cm) for the dye volume of 2 x 5 x 40 cu mm and the optimum dye concentration of 0.001 M. The threshold is about one-third of that achievable with a high-intensity solar concentrator.

  19. Blood Pump Bearing System

    NASA Technical Reports Server (NTRS)

    Aber, Gregory S. (Inventor)

    2000-01-01

    An apparatus is provided for a blood pump bearing system within a pump housing to support long-term highspeed rotation of a rotor with an impeller blade having a plurality of individual magnets disposed thereon to provide a small radial air gap between the magnets and a stator of less than 0.025 inches. The bearing system may be mounted within a flow straightener, diffuser, or other pump element to support the shaft of a pump rotor. The bearing system includes a zirconia shaft having a radiused end. The radiused end has a first radius selected to be about three times greater than the radius of the zirconia shaft. The radiused end of the zirconia shaft engages a flat sapphire endstone. Due to the relative hardness of these materials a flat is quickly produced during break-in on the zirconia radiused end of precisely the size necessary to support thrust loads whereupon wear substantially ceases. Due to the selection of the first radius, the change in shaft end-play during pump break-in is limited to a total desired end-play of less than about 0.010 inches. Radial loads are supported by an olive hole ring jewel that makes near line contact around the circumference of the Ir shaft to support big speed rotation with little friction. The width of olive hole ring jewel is small to allow heat to conduct through to thereby prevent heat build-up in the bearing. A void defined by the bearing elements may fill with blood that then coagulates within the void. The coagulated blood is then conformed to the shape of the bearing surfaces.

  20. Blood Pump Bearing System

    NASA Technical Reports Server (NTRS)

    Aber, Gregory S. (Inventor)

    1999-01-01

    Methods and apparatus are provided for a blood pump bearing system within a pump housing to support long-term high-speed rotation of a rotor with an impeller blade having a plurality of individual magnets disposed thereon to provide a small radial air gap between the magnets and a stator of less than 0.025 inches. The bearing system may be mounted within a flow straightener, diffuser, or other pump element to support the shaft of a pump rotor. The bearing system includes a zirconia shaft having a radiused end. The radiused end has a first radius selected to be about three times greater than the radius of the zirconia shaft. The radiused end of the zirconia shaft engages a flat sapphire endstone. Due to the relative hardness of these materials a flat is quickly produced during break-in on the zirconia radiused end of precisely the size necessary to support thrust loads whereupon wear substantially ceases. Due to the selection of the first radius, the change in shaft end-play during pump break-in is limited to a total desired end-play of less than about 0.010 inches. Radial loads are supported by an olive hole ring jewel that makes near line contact around the circumference of the shaft to support high speed rotation with little friction. The width of olive hole ring jewel is small to allow heat to conduct through to thereby prevent heat build-up in the bearing. A void defined by the bearing elements may fill with blood that then coagulates within the void. The coagulated blood is then conformed to the shape of the bearing surfaces.

  1. 980nm diode laser pump modules operating at high temperature

    NASA Astrophysics Data System (ADS)

    Campbell, Jenna; Semenic, Tadej; Leisher, Paul; Bhunia, Avijit; Mashanovitch, Milan; Renner, Daniel

    2016-03-01

    Existing thermal management technologies for diode laser pumps place a significant load on the size, weight and power consumption of High Power Solid State and Fiber Laser systems, thus making current laser systems very large, heavy, and inefficient in many important practical applications. This problem is being addressed by the team formed by Freedom Photonics and Teledyne Scientific through the development of novel high power laser chip array architectures that can operate with high efficiency when cooled with coolants at temperatures higher than 50 degrees Celsius and also the development of an advanced thermal management system for efficient heat extraction from the laser chip array. This paper will present experimental results for the optical, electrical and thermal characteristics of 980 nm diode laser pump modules operating effectively with liquid coolant at temperatures above 50 degrees Celsius, showing a very small change in performance as the operating temperature increases from 20 to 50 degrees Celsius. These pump modules can achieve output power of many Watts per array lasing element with an operating Wall-Plug-Efficiency (WPE) of >55% at elevated coolant temperatures. The paper will also discuss the technical approach that has enabled this high level of pump module performance and opportunities for further improvement.

  2. Lasing properties of chromium-aluminum-doped forsterite pumped with an alexandrite laser

    SciTech Connect

    Behrens, E.G.; Jani, M.G.; Powell, R.C. ); Verdun, H.R. ); Pinto, A. )

    1991-08-01

    This paper reports on the lasing properties of chromium-aluminum-doped forsterite that were investigated using a tunable alexandrite laser as the pump source. Results of measurements of the lasing threshold, slope efficiency, spectral, and temporal profiles of the laser pulse, and the time delay between the alexandrite pump pulse and the laser emission are presented for pump wavelengths of 770, 746, and 730 nm and different pump beam energies. Laser rate equations are developed to model the lasing center as a four-level system and applied to the case of 746 nm pumping.

  3. Laser Wakefield acceleration with high relativistic pumps

    NASA Astrophysics Data System (ADS)

    Katsouleas, T.; Mori, W. B.; Darrow, C. B.

    1989-10-01

    Preliminary scaling laws are found for the laser wakefield accelerator in the very non-linear regime where the normalized laser pump strengh Voscc=eE0/mω0c≳1. Two important non-linear effects are an increase in the wake phase velocity (and hence the particle dephasing length) and an increase in the laser pulse length for optimal wake excitation. Application of the results to the proposed Livermore High-Brightness Lasers (HBL) is discussed here and in the accompanying paper by C. B. Darrow, et al. A preliminary 1-D PIC simulation is presented.

  4. Laser satellite power systems

    SciTech Connect

    Walbridge, E.W.

    1980-01-01

    A laser satellite power system (SPS) converts solar power captured by earth-orbiting satellites into electrical power on the earth's surface, the satellite-to-ground transmission of power being effected by laser beam. The laser SPS may be an alternative to the microwave SPS. Microwaves easily penetrate clouds while laser radiation does not. Although there is this major disadvantage to a laser SPS, that system has four important advantages over the microwave alternative: (1) land requirements are much less, (2) radiation levels are low outside the laser ground stations, (3) laser beam sidelobes are not expected to interfere with electromagnetic systems, and (4) the laser system lends itself to small-scale demonstration. After describing lasers and how they work, the report discusses the five lasers that are candidates for application in a laser SPS: electric discharge lasers, direct and indirect solar pumped lasers, free electron lasers, and closed-cycle chemical lasers. The Lockheed laser SPS is examined in some detail. To determine whether a laser SPS will be worthy of future deployment, its capabilities need to be better understood and its attractiveness relative to other electric power options better assessed. First priority should be given to potential program stoppers, e.g., beam attenuation by clouds. If investigation shows these potential program stoppers to be resolvable, further research should investigate lasers that are particularly promising for SPS application.

  5. Advancements in flowing diode pumped alkali lasers

    NASA Astrophysics Data System (ADS)

    Pitz, Greg A.; Stalnaker, Donald M.; Guild, Eric M.; Oliker, Benjamin Q.; Moran, Paul J.; Townsend, Steven W.; Hostutler, David A.

    2016-03-01

    Multiple variants of the Diode Pumped Alkali Laser (DPAL) have recently been demonstrated at the Air Force Research Laboratory (AFRL). Highlights of this ongoing research effort include: a) a 571W rubidium (Rb) based Master Oscillator Power Amplifier (MOPA) with a gain (2α) of 0.48 cm-1, b) a rubidium-cesium (Cs) Multi-Alkali Multi-Line (MAML) laser that simultaneously lases at both 795 nm and 895 nm, and c) a 1.5 kW resonantly pumped potassium (K) DPAL with a slope efficiency of 50%. The common factor among these experiments is the use of a flowing alkali test bed.

  6. High power tandem-pumped thulium-doped fiber laser.

    PubMed

    Wang, Yao; Yang, Jianlong; Huang, Chongyuan; Luo, Yongfeng; Wang, Shiwei; Tang, Yulong; Xu, Jianqiu

    2015-02-01

    We propose a cascaded tandem pumping technique and show its high power and high efficient operation in the 2-μm wavelength region, opening up a new way to scale the output power of the 2-μm fiber laser to new levels (e.g. 10 kW). Using a 1942 nm Tm(3+) fiber laser as the pump source with the co- (counter-) propagating configuration, the 2020 nm Tm(3+) fiber laser generates 34.68 W (35.15W) of output power with 84.4% (86.3%) optical-to-optical efficiency and 91.7% (92.4%) slope efficiency, with respect to launched pump power. It provides the highest slope efficiency reported for 2-μm Tm(3+)-doped fiber lasers, and the highest output power for all-fiber tandem-pumped 2-μm fiber oscillators. This system fulfills the complete structure of the proposed cascaded tandem pumping technique in the 2-μm wavelength region (~1900 nm → ~1940 nm → ~2020 nm). Numerical analysis is also carried out to show the power scaling capability and efficiency of the cascaded tandem pumping technique. PMID:25836159

  7. Well-pump alignment system

    DOEpatents

    Drumheller, D.S.

    1998-10-20

    An improved well-pump for geothermal wells, an alignment system for a well-pump, and to a method for aligning a rotor and stator within a well-pump are disclosed, wherein the well-pump has a whistle assembly formed at a bottom portion thereof, such that variations in the frequency of the whistle, indicating misalignment, may be monitored during pumping. 6 figs.

  8. Solar pumped laser technology options for space power transmission

    NASA Technical Reports Server (NTRS)

    Conway, E. J.

    1986-01-01

    An overview of long-range options for in-space laser power transmission is presented. The focus is on the new technology and research status of solar-pumped lasers and their solar concentration needs. The laser options include gas photodissociation lasers, optically-pumped solid-state lasers, and blackbody-pumped transfer lasers. The paper concludes with a summary of current research thrusts.

  9. Flashlamp-pumped iodine monobromide laser characteristics

    NASA Technical Reports Server (NTRS)

    Zapata, L. E.; De Young, R. J.

    1983-01-01

    The operating characteristics of a flashlamp-pumped IBr laser were investigated to evaluate its suitability for solar-pumped laser applications. A peak power of 350 W/sq cm at 2.7 microns was achieved at 12-torr IBr pressure. At 500-J flashlamp energy, the IBr output saturated; a gain of 0.17% per cm was measured for IBr. Neon was found to be effective for enhancing the recombination of the photodissociation products. With neon as a buffer gas, the laser pulse length was extended to 53 microsec. The termination of the laser pulse, within the flashlamp pulse, is thought to be due to the temperature rise in the gas. Increasing the IBr initial temperature decreased the lasing output. At 300 C, output dropped to approximately one-half the room temperature value. The dominant quencher is thought to be atomic iodine. IBr was found to couple better to the flashlamp energy than C3F7I.

  10. Development of Ho:YLF laser pumped by Tm:fiber laser

    NASA Astrophysics Data System (ADS)

    Mizutani, Kohei; Ishii, Shoken; Itabe, Toshikazu; Asai, Kazuhiro; Sato, Atsushi

    2014-11-01

    We are developing a 2-micron Ho:YLF laser end-pumped by Tm:fiber laser. The oscillator has ring resonator of 3m length. The laser is operated at high repetition rate of 200-5000 Hz in room temperature. The oscillator and amplifier system showed outputs of about 9W in CW and more than 6W in Q-switched operation. This laser will be used for wind and CO2 concentration measurements.

  11. High-Beam-Quality All-Solid-State 355 nm Ultraviolet Pulsed Laser Based on a Master-Oscillator Power-Amplifier System Pumped at 888 nm

    NASA Astrophysics Data System (ADS)

    Hong, Hailong; Liu, Qiang; Huang, Lei; Gong, Mali

    2012-09-01

    An efficient all-solid-state 355 nm ultraviolet laser based on an 888 nm pumped master-oscillator power-amplifier (MOPA) system is presented. Due to the high beam quality of the fundamental wave being superior to 1.15 (M2) under all pump powers and pulse repetition frequencies (PRFs), the UV laser has the advantage of being able to operate continuously from zero to maximum power. The maximum green and UV output powers were 45.9 W at 50 kHz and 24.3 W at 65 kHz with the corresponding conversion efficiencies from IR-to-green and IR-to-UV of 66.0% and 34.1%, respectively.

  12. Future directions in 980-nm pump lasers: submarine deployment to low-cost watt-class terrestrial pumps

    NASA Astrophysics Data System (ADS)

    Gulgazov, Vadim N.; Jackson, Gordon S.; Lascola, Kevin M.; Major, Jo S.; Parke, Ross; Richard, Tim; Rossin, Victor V.; Zhang, Kai

    1999-09-01

    The demands of global bandwidth and distribution are rising rapidly as Internet usage grows. This fundamentally means that more photons are flowing within optical cables. While transmitting sources launches some optical power, the majority of the optical power that is present within modern telecommunication systems originates from optical amplifiers. In addition, modern optical amplifiers offer flat optical gain over broad wavelength bands, thus making possible dense wavelength de-multiplexing (DWDM) systems. Optical amplifier performance, and by extension the performance of the laser pumps that drive them, is central to the future growth of both optical transmission and distribution systems. Erbium-doped amplifiers currently dominate optical amplifier usage. These amplifiers absorb pump light at 980 nm and/or 1480 nm, and achieve gain at wavelengths around 1550 nm. 980 nm pumps achieve better noise figures and are therefore used for the amplification of small signals. Due to the quantum defect, 1480 nm lasers deliver more signal photon per incident photon. In addition, 1480 nm lasers are less expensive than 980 nm lasers. Thus, 1480 nm pump lasers are used for amplification in situations where noise is not critical. The combination of these traits leads to the situation where many amplifiers contain 980 nm lasers to pump the input section of the Er- doped fiber with 1480 nm lasers being used to pump the latter section of Er fiber. This can be thought of as using 980 nm lasers to power an optical pre-amplifier with the power amplification function being pump with 1480 nm radiation. This paper will focus on 980 nm pump lasers and the impact that advances in 980 nm pump technology will have on optical amplification systems. Currently, 980 nm technology is rapidly advancing in two areas, power and reliability. Improving reliability is becoming increasingly important as amplifiers move towards employing more pump lasers and using these pump lasers without redundancy

  13. Relaxation oscillations in optically pumped molecular lasers

    NASA Technical Reports Server (NTRS)

    Lawandy, N. M.; Koepf, G. A.

    1980-01-01

    The observation of relaxation oscillations in both the (C-13)H3F and (C-12)H3F optically pumped lasers is reported. Expressions are derived for the oscillation frequency and its temperature and pressure dependences using a four-level rate equation model. Excellent agreement between measured frequencies and the theory presented is observed. Models are considered for using this phenomenon to determine the rotational and vibrational relaxation mechanisms of the laser gases.

  14. Solar-pumped CO laser

    NASA Astrophysics Data System (ADS)

    Treanor, Charles E.

    This paper describes a method of converting thermal radiation directly into laser radiation at a wavelength of about 5 micrometers. The working fluid for the laser operation is a mixture of carbon monoxide and argon. The source of thermal radiation is assumed to be a solar oven or electrical oven operating in the range of 2000 to 2500 K. The use of carbon monoxide as the lasing material presents the advantage that the absorbing lines can be pressure broadened to permit efficient absorption of the thermal radiation without unacceptable increases in vibrational relaxation. Estimates of the efficiency, size, and power loading of such a laser are discussed.

  15. Absorption heat pump system

    DOEpatents

    Grossman, Gershon; Perez-Blanco, Horacio

    1984-01-01

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  16. Optically pumped pulsed Li/sub 2/ laser

    SciTech Connect

    Kaslin, V.; Yakushev, O.

    1982-02-01

    Pulsed lasing was obtained for the first time from Li/sub 2/ molecules by optical pumping with radiation from a pulsed copper vapor laser (578.2 nm, pulse repetition frequency 5 kHz). The laser transitions, with wavelengths in the range 867--907 nm, belong to the electronic A/sup 1/..sigma../sup +//sub u/--X/sup 1/..sigma../sup +//sub g/ system. With a pump power of 190 mW, an average output power of 8 mW was achieved with an efficiency for the conversion of the optical pumping energy of 7%. A number of Li/sub 2/ laser emission lines were observed in the superradiant regime.

  17. High efficiency cw laser-pumped tunable alexandrite laser

    SciTech Connect

    Lai, S.T.; Shand, M.L.

    1983-10-01

    High efficiency cw alexandrite laser operation has been achieved. With longitudinal pumping by a krypton laser in a nearly concentric cavity, a 51% output power slope efficiency has been measured. Including the transmission at the input coupler mirror, a quantum yield of 85% has been attained above threshold. Tunability from 726 to 802 nm has also been demonstrated. The low loss and good thermal properties make alexandrite ideal for cw laser operation.

  18. CW arc-lamp-pumped alexandrite lasers

    SciTech Connect

    Samelson, H.; Walling, J.C.; Wernikowski, T.; Harter, D.J.

    1988-06-01

    The performance characteristics of arc-lamp- (Xe and Hg) pumped, CW alexandrite lasers are described in detail. The modes of operation considered are free running, tuned, and repetitively Q-switched. The experimental arrangement and apparatus are also outlined. The experimental results are discussed in terms of a steady-state model, and the areas of agreement and difficulty are pointed out.

  19. Two-beam combined 3.36  J, 100  Hz diode-pumped high beam quality Nd:YAG laser system.

    PubMed

    Qiu, J S; Tang, X X; Fan, Z W; Wang, H C; Liu, H

    2016-07-20

    In this paper, we develop a diode-pumped all-solid-state high-energy and high beam quality Nd:YAG laser system. A master oscillator power amplifier structure is used to provide a high pulse energy laser output with a high repetition rate. In order to decrease the amplifier working current so as to reduce the impact of the thermal effect on the beam quality, a beam splitting-amplifying-combining scheme is adopted. The energy extraction efficiency of the laser system is 50.68%. We achieve 3.36 J pulse energy at a 100 Hz repetition rate with a pulse duration of 7.1 ns, a far-field beam spot 1.71 times the diffraction limit, and 1.07% energy stability (RMS). PMID:27463917

  20. Theoretical studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, W. L.

    1982-01-01

    Solar-pumped lasers were investigated by comparing experimental results from pulse experiments with steady state calculations. The time varying behavior of an IBr laser is studied. The analysis is only approximate, but indicates that conditions occurring in a pulsed experiment are quite different from those at steady state. The possibility of steady-state lasing in an IBr laser is determined. The effects of high temperatures on the quenching and recombination rates are examined. Although uncertainties in the values of the rate coefficients make it difficult to draw firm conclusions, it seems steady state running may be possible at high temperatures.

  1. Diode-Pumped Mode-Locked LiSAF Laser

    SciTech Connect

    1996-02-01

    Under this contract we have developed Cr{sup 3+}:LiSrAlF{sub 6} (Cr:LiSAF, LiSAF) mode-locked lasers suitable for generation of polarized electrons for CEBAF. As 670 nm is an excellent wavelength for optical pumping of Cr:LiSAF, we have used a LIGHTWAVE developed 670 nm diode pump module that combines the output of ten diode lasers and yields approximately 2 Watts of optical power. By the use of a diffraction limited pump beam however, it is possible to maintain a small mode size through the length of the crystal and hence extract more power from Cr:LiSAF laser. For this purpose we have developed a 1 Watt, red 660nm laser (LIGHTWAVE model 240R) which serves as an ideal pump for Cr:LiSAF and is a potential replacement of costly and less robust krypton laser. This new system is to compliment LIGHTWAVE Series 240, and is currently being considered for commercialization. Partially developed under this contract is LIGHTWAVEs product model 240 which has already been in our production lines for a few months and is commercially available. This laser produces 2 Watts of output at 532 nm using some of the same technology developed for production of the 660nm red system. It is a potential replacement for argon ion lasers and has better current and cooling requirements and is an excellent pump source for Ti:Al{sub 2}O{sub 3}. Also, as a direct result of this contract we now have the capability of commercially developing a mode-locked 100MHz Cr:LiSAF system. Such a laser could be added to our 100 MHz LIGHTWAVE Series 131. The Series 131 lasers provide pico second pulses and were originally developed under another DOE SBIR. Both models of LIGHTWAVE Series 240 lasers, the fiber coupled pump module and the 100MHz LiSAF laser of Series 131 have been partially developed under this contract, and are commercially competitive products.

  2. Mode locking of diode- and flashlamp-pumped Nd:YAG lasers using semiconductor saturable absorbers

    NASA Astrophysics Data System (ADS)

    Dombrovsky, Andrej; Kubecek, Vaclav; Zvonicek, K.; Diels, Jean-Claude M.; Stintz, Andreas

    2003-07-01

    Operation of laser diode and flash lamp pumped Nd:YAG lasers mode locked with two different types of semiconductor saturable absorbers is reported. In the first type that is used mainly in diode pumped systems the absorber layers are integrated on highly reflective Bragg mirror. The second type is for use in transmission mode inside the resonator. Different design of semiconductor elements, pumping geometries and resonator configurations were investigated and characteristics of laser operation in mode-locked regime are presented.

  3. Efficiency and threshold pump intensity of CW solar-pumped solid-state lasers

    SciTech Connect

    Hwang, I.H. . Dept. of Physics); Lee, J.H. . Langley Research Center)

    1991-09-01

    This paper reports on the efficiencies and threshold pump intensities of various solid-state laser materials that have been estimated to compare their performance characteristics as direct solar-pumped CW lasers. Among the laser materials evaluated in this research, alexandrite has the highest slope efficiency of about 12.6%; however, it does not seem to be practical for solar-pumped laser application because of its high threshold pump intensity. Cr:Nd:GSGG is the most promising for solar-pumped lasing. Its threshold pump intensity is about 100 air-mass-zero (AMO) solar constants and its slope efficiency is about 12% when thermal deformation is completely prevented.

  4. Pump and probe spectroscopy with continuous wave quantum cascade lasers

    SciTech Connect

    Kirkbride, James M. R.; Causier, Sarah K.; Dalton, Andrew R.; Ritchie, Grant A. D.; Weidmann, Damien

    2014-02-07

    This paper details infra-red pump and probe studies on nitric oxide conducted with two continuous wave quantum cascade lasers both operating around 5 μm. The pump laser prepares a velocity selected population in a chosen rotational quantum state of the v = 1 level which is subsequently probed using a second laser tuned to a rotational transition within the v = 2 ← v = 1 hot band. The rapid frequency scan of the probe (with respect to the molecular collision rate) in combination with the velocity selective pumping allows observation of marked rapid passage signatures in the transient absorption profiles from the polarized vibrationally excited sample. These coherent transient signals are influenced by the underlying hyperfine structure of the pump and probe transitions, the sample pressure, and the coherent properties of the lasers. Pulsed pump and probe studies show that the transient absorption signals decay within 1 μs at 50 mTorr total pressure, reflecting both the polarization and population dephasing times of the vibrationally excited sample. The experimental observations are supported by simulation based upon solving the optical Bloch equations for a two level system.

  5. Dye laser pumped, continuous-wave KTP optical parametric oscillators

    NASA Astrophysics Data System (ADS)

    Klein, M. E.; Scheidt, M.; Boller, K.-J.; Wallenstein, R.

    1998-06-01

    We report on dye-laser-pumped, continuous-wave (CW) KTiOPO4 (KTP) optical parametric oscillators (OPOs) with pump and idler resonant cavities. With a linear two-mirror cavity the pump power at threshold was 70 mW. The single-frequency signal and idler output wavelengths were tuned in the range of 1025 to 1040 nm and 1250 to 1380 nm by tuning the dye laser in the range of 565 to 588 nm. With a dual three-mirror cavity the threshold was 135 mW. Pumped by 500 mW of 578 nm radiation the 1040 nm single-frequency signal wave output power was 84 mW. Power and frequency stable operation with a spectral bandwidth of less than 9 MHz was obtained by piezo-electrically locking the length of the pump resonant cavity to the dye laser wavelength. Similar performance was achieved by placing the idler resonant OPO inside the resonator of the dye laser. With this system power stable and single-frequency operation was achieved with a spectral bandwidth of less than 11 MHz for the idler wave.

  6. High power diode lasers for solid-state laser pumps

    NASA Astrophysics Data System (ADS)

    Linden, Kurt J.; McDonnell, Patrick N.

    1994-02-01

    The development and commercial application of high power diode laser arrays for use as solid-state laser pumps is described. Such solid-state laser pumps are significantly more efficient and reliable than conventional flash-lamps. This paper describes the design and fabrication of diode lasers emitting in the 780 - 900 nm spectral region, and discusses their performance and reliability. Typical measured performance parameters include electrical-to-optical power conversion efficiencies of 50 percent, narrow-band spectral emission of 2 to 3 nm FWHM, pulsed output power levels of 50 watts/bar with reliability values of over 2 billion shots to date (tests to be terminated after 10 billion shots), and reliable operation to pulse lengths of 1 ms. Pulse lengths up to 5 ms have been demonstrated at derated power levels, and CW performance at various power levels has been evaluated in a 'bar-in-groove' laser package. These high-power 1-cm stacked-bar arrays are now being manufactured for OEM use. Individual diode laser bars, ready for package-mounting by OEM customers, are being sold as commodity items. Commercial and medical applications of these laser arrays include solid-state laser pumping for metal-working, cutting, industrial measurement and control, ranging, wind-shear/atmospheric turbulence detection, X-ray generation, materials surface cleaning, microsurgery, ophthalmology, dermatology, and dental procedures.

  7. High power diode lasers for solid-state laser pumps

    NASA Technical Reports Server (NTRS)

    Linden, Kurt J.; Mcdonnell, Patrick N.

    1994-01-01

    The development and commercial application of high power diode laser arrays for use as solid-state laser pumps is described. Such solid-state laser pumps are significantly more efficient and reliable than conventional flash-lamps. This paper describes the design and fabrication of diode lasers emitting in the 780 - 900 nm spectral region, and discusses their performance and reliability. Typical measured performance parameters include electrical-to-optical power conversion efficiencies of 50 percent, narrow-band spectral emission of 2 to 3 nm FWHM, pulsed output power levels of 50 watts/bar with reliability values of over 2 billion shots to date (tests to be terminated after 10 billion shots), and reliable operation to pulse lengths of 1 ms. Pulse lengths up to 5 ms have been demonstrated at derated power levels, and CW performance at various power levels has been evaluated in a 'bar-in-groove' laser package. These high-power 1-cm stacked-bar arrays are now being manufactured for OEM use. Individual diode laser bars, ready for package-mounting by OEM customers, are being sold as commodity items. Commercial and medical applications of these laser arrays include solid-state laser pumping for metal-working, cutting, industrial measurement and control, ranging, wind-shear/atmospheric turbulence detection, X-ray generation, materials surface cleaning, microsurgery, ophthalmology, dermatology, and dental procedures.

  8. Microwave accelerator E-beam pumped laser

    DOEpatents

    Brau, Charles A.; Stein, William E.; Rockwood, Stephen D.

    1980-01-01

    A device and method for pumping gaseous lasers by means of a microwave accelerator. The microwave accelerator produces a relativistic electron beam which is applied along the longitudinal axis of the laser through an electron beam window. The incident points of the electron beam on the electron beam window are varied by deflection coils to enhance the cooling characteristics of the foil. A thyratron is used to reliably modulate the microwave accelerator to produce electron beam pulses which excite the laser medium to produce laser pulse repetition frequencies not previously obtainable. An aerodynamic window is also disclosed which eliminates foil heating problems, as well as a magnetic bottle for reducing laser cavity length and pressures while maintaining efficient energy deposition.

  9. Efficient bone cutting with the novel diode pumped Er:YAG laser system: in vitro investigation and optimization of the treatment parameters

    NASA Astrophysics Data System (ADS)

    Stock, Karl; Diebolder, Rolf; Hausladen, Florian; Hibst, Raimund

    2014-03-01

    It is well known that flashlamp pumped Er:YAG lasers allow efficient bone ablation due to strong absorption at 3μm by water. Preliminary experiments revealed also a newly developed diode pumped Er:YAG laser system (Pantec Engineering AG) to be an efficient tool for use for bone surgery. The aim of the present in vitro study is the investigation of a new power increased version of the laser system with higher pulse energy and optimization of the treatment set-up to get high cutting quality, efficiency, and ablation depth. Optical simulations were performed to achieve various focus diameters and homogeneous beam profile. An appropriate experimental set-up with two different focusing units, a computer controlled linear stage with sample holder, and a shutter unit was realized. By this we are able to move the sample (slices of pig bone) with a defined velocity during the irradiation. Cutting was performed under appropriate water spray by moving the sample back and forth. After each path the ablation depth was measured and the focal plane was tracked to the actual bottom of the groove. Finally, the cuts were analyzed by light microcopy regarding the ablation quality and geometry, and thermal effects. In summary, the results show that with carefully adapted irradiation parameters narrow and deep cuts (ablation depth > 6mm, aspect ratio approx. 20) are possible without carbonization. In conclusion, these in vitro investigations demonstrate that high efficient bone cutting is possible with the diode pumped Er:YAG laser system using appropriate treatment set-up and parameters.

  10. Vacuum system pump down analysis

    SciTech Connect

    Rohrdanz, D.R.

    1990-08-01

    My assignment on the SP-100 Vacuum Vessel Vacuum System Team was to perform a transient pump down analysis for the vacuum vessel that will house the SP-100 reactor during testing. Pump down time was calculated for air and helium. For all cases the proposed vacuum system will be able to pump down the vessel within the required time. The use of a larger rotary piston pump (DUO250) improves the pump down time by 35 minutes and therefore should be considered. The 6-inch duct for the roughing line is optimal, however, because all cases are well below the 24 hour time frame, the 4-inch duct is sufficient. The use of the single turbomolecular pump during pump down is sufficient. A pump down with helium in the vessel and a helium inleakage delays the time to achieve the base pressure marginally and is acceptable.

  11. Photovoltaic converters for solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Walker, Gilbert H.; Heinbockel, John H.

    1988-01-01

    The authors describe a mathematical parametric study of converters used to convert laser radiation to electricity for space-based laser power systems. Two different lasers, the 1.06-micron Nd laser and the 1.315-micron iodine laser, are used in the vertical junction converter. The calculated efficiency is 50 percent for a 100-junction Si photovoltaic converter when used with a Nd laser. The calculated efficiency for a 1000-junction Ga(0.53)In(0.47)As photovoltaic converter is 43 percent when used with an iodine laser.

  12. A portable lidar using a diode-pumped YAG laser

    NASA Technical Reports Server (NTRS)

    Takeuchi, N.; Okumura, H.; Sugita, T.; Matsumoto, H.; Yamaguchi, S.

    1992-01-01

    A Mie lidar system is technically established and is used for monitoring air pollution, stratospheric and boundary layer aerosol distribution, plume dispersion, visibility, and the study of atmospheric structure and cloud physics. However, a lidar system is not widely used because of its cumbersome handling and unwieldy portability. Although the author developed a laser diode lidar system based on RM-CW technique, it has a limit of measurement distance. Here we report the development of an all solid Mie lidar system using a diode-pumped Nd:YAG laser and a Si-APD detector. This was constructed as a prototype of a handy lidar system.

  13. Fuel pumping system and method

    DOEpatents

    Shafer, Scott F.; Wang, Lifeng ,

    2006-12-19

    A fuel pumping system that includes a pump drive is provided. A first pumping element is operatively connected to the pump drive and is operable to generate a first flow of pressurized fuel. A second pumping element is operatively connected to the pump drive and is operable to generate a second flow of pressurized fuel. A first solenoid is operatively connected to the first pumping element and is operable to vary at least one of a fuel pressure and a fuel flow rate of the first flow of pressurized fuel. A second solenoid is operatively connected to the second pumping element and is operable to vary at least one of a fuel pressure and a fuel flow rate of the second flow of pressurized fuel.

  14. Fuel Pumping System And Method

    DOEpatents

    Shafer, Scott F.; Wang, Lifeng

    2005-12-13

    A fuel pumping system that includes a pump drive is provided. A first pumping element is operatively connected to the pump drive and is operable to generate a first flow of pressurized fuel. A second pumping element is operatively connected to the pump drive and is operable to generate a second flow of pressurized fuel. A first solenoid is operatively connected to the first pumping element and is operable to vary at least one of a fuel pressure and a fuel flow rate of the first flow of pressurized fuel. A second solenoid is operatively connected to the second pumping element and is operable to vary at least one of a fuel pressure and a fuel flow rate of the second flow of pressurized fuel.

  15. Dynamics of photon-induced processes in adsorbate-surface systems studied by laser-synchrotron pump-probe techniques

    NASA Astrophysics Data System (ADS)

    Winter, Bernd J.; Gatzke, Johannes; Quast, T.; Will, Ingo; Wick, Manfred T.; Liero, A.; Pop, D.; Hertel, Ingolf V.

    1998-12-01

    We report on the MBI User Facility at BESSY II, presently under construction, which is dedicated to study the dynamics of photo-induced processes by combining laser and synchrotron pulses. In this paper we focus on the synchronization of a modelocked ultrafast Ti:sapphire laser to the Berlin electron storage ring for synchrotron radiation (BESSY). Two different techniques have been applied -- one based on a digital phase comparator and the other based on analog high-harmonic mixing. Both schemes may be easily adjusted to either single, multi- or hybrid-bunch operation of the synchrotron. Moreover, the temporal accuracy of the synchronization unit suitably matches the widths of the synchrotron pulses (some ten picoseconds) to be expected at BESSY II. Therefore, the currently performed test experiments at BESSY I provide the basis for time- resolved photon-induced experiments which combine laser and SR-undulator pulses in a pump-probe scheme at BESSY II. This facility will be available within the first half of 1999.

  16. Diode pumped solid-state laser oscillators for spectroscopic applications

    NASA Technical Reports Server (NTRS)

    Byer, R. L.; Basu, S.; Fan, T. Y.; Kozlovsky, W. J.; Nabors, C. D.; Nilsson, A.; Huber, G.

    1987-01-01

    The rapid improvement in diode laser pump sources has led to the recent progress in diode laser pumped solid state lasers. To date, electrical efficiencies of greater than 10 percent were demonstrated. As diode laser costs decrease with increased production volume, diode laser and diode laser array pumped solid state lasers will replace the traditional flashlamp pumped Nd:YAG laser sources. The use of laser diode array pumping of slab geometry lasers will allow efficient, high peak and average power solid state laser sources to be developed. Perhaps the greatest impact of diode laser pumped solid state lasers will be in spectroscopic applications of miniature, monolithic devices. Single-stripe diode-pumped operation of a continuous-wave 946 nm Nd:YAG laser with less than 10 m/w threshold was demonstrated. A slope efficiency of 16 percent near threshold was shown with a projected slope efficiency well above a threshold of 34 percent based on results under Rhodamine 6G dye-laser pumping. Nonlinear crystals for second-harmonic generation of this source were evaluated. The KNbO3 and periodically poled LiNbO3 appear to be the most promising.

  17. Laser Wakefield acceleration with high relativistic pumps

    SciTech Connect

    Katsouleas, T.; Mori, W.B. ); Darrow, C.B. )

    1989-10-15

    Preliminary scaling laws are found for the laser wakefield accelerator in the very non-linear regime where the normalized laser pump strengh {ital V}{sub osc}{ital c}={ital eE}{sub 0}/{ital m}{omega}{sub 0}{ital c}{gt}1. Two important non-linear effects are an increase in the wake phase velocity (and hence the particle dephasing length) and an increase in the laser pulse length for optimal wake excitation. Application of the results to the proposed Livermore High-Brightness Lasers (HBL) is discussed here and in the accompanying paper by C. B. Darrow, {ital et} {ital al}. A preliminary 1-D PIC simulation is presented. {copyright} 1989 American Institute of Physics

  18. University of Florida nuclear pumped laser program. [excitation of laser gaseous

    NASA Technical Reports Server (NTRS)

    Schneider, R. T.

    1979-01-01

    The mechanism of excitation of laser gases by fast ions (triton, proton, or fission fragments) and especially any role UF6 might play in radiative deexcitation of these gases were investigated. Population densities of excited important for laser action were obtained. Nuclear pumped CW-laser systems, especially He-Ne and CO2, were studied using steady state reactors. It was demonstrated that He-Ne lases in a CW-mode with nuclear pumping at both the red and the infrared transition. The infrared transition was observed to be superradiant.

  19. Efficiency and threshold pump intensity of CW solar-pumped solid-state lasers

    NASA Technical Reports Server (NTRS)

    Hwang, In H.; Lee, Ja H.

    1991-01-01

    The authors consider the relation between the threshold pumping intensity, the material properties, the resonator parameters, and the ultimate slope efficiencies of various solid-state laser materials for solar pumping. They clarify the relation between the threshold pump intensity and the material parameters and the relation between the ultimate slope efficiency and the laser resonator parameters such that a design criterion for the solar-pumped solid-state laser can be established. Among the laser materials evaluated, alexandrite has the highest slope efficiency of about 12.6 percent; however, it does not seem to be practical for a solar-pumped laser application because of its high threshold pump intensity. Cr:Nd:GSGG is the most promising for solar-pumped lasing. Its threshold pump intensity is about 100 air-mass-zero (AM0) solar constants and its slope efficiency is about 12 percent when thermal deformation is completely prevented.

  20. Diode pumped alkali lasers (DPALs): an overview

    NASA Astrophysics Data System (ADS)

    Krupke, William F.

    2008-05-01

    The concept of power-scalable, high beam-quality diode pumped alkali lasers was introduced in 2003 [Krupke, US Patent No. 6,643,311; Opt. Letters, 28, 2336 (2003)]. Since then several laboratory DPAL devices have been reported on, confirming many of the spectroscopic, kinetic, and laser characteristics projected from literature data. This talk will present an overview of the DPAL concept, summarize key relevant properties of the cesium, rubidium, and potassium alkali vapor gain media so-far examined, outline power scaling considerations, and highlight results of published DPAL laboratory experiments.

  1. Multi-lamp laser pumping cavity

    SciTech Connect

    Kuppenheimer, J.D. Jr.

    1987-07-21

    An optically pumped laser comprises: A. a cylindrical laser rod having a longitudinal central rod axis; B. cylindrical lamps for optically pumping the laser rod. The lamps have longitudinal central lamp axes parallel to the rod axis. The lamps being so located with respect to each other and to the laser rod as to define in cross section a base line associated with each lamp and extending between the rod axis and the lamp axis of the associated lamp. The base lines being equal in length and equiangularly spaced; and C. a reflector wall consisting essentially of first and second wall sections associated with each lamp, the cross sections of the first and second wall sections associated with a given lamp essentially following first and second curves extending from a lamp cusp associated with the given lamp to second and first rod cusps, respectively, associated with the given lamp. The first and second curves consist of the loci of points to which the sums of the distances, exterior to the laser rod and the given lamp, from first and second rod starting points, respectively, associated with the given lamp and from first and second lamp starting points, respectively, on the given lamp equal a fixed quantity.

  2. The pumping mechanism for the neon-nitrogen nuclear excited laser

    NASA Technical Reports Server (NTRS)

    Cooper, G. W.; Verdeyen, J. T.; Wells, W. E.; Miley, G. H.

    1976-01-01

    In order to determine the physical processes for pumping this laser, a detailed study of the afterglow system has been performed. The pumping mechanism has been found to be collisional-radiative electron-ion recombination. Microwave quenching of both the laser and spontaneous afterglow light have shown conclusively that a recombination process directly produces a nitrogen atom in either the upper laser level or, more likely, in a higher lying energy level which rapidly de-excites to the upper laser level.

  3. Design and development of a high-power LED-pumped Ce:Nd:YAG laser.

    PubMed

    Villars, Brenden; Steven Hill, E; Durfee, Charles G

    2015-07-01

    By studying quasi-continuous wave (QCW) operation of a Ce:Nd:YAG solid-state laser directly pumped by LED arrays, we demonstrate the feasibility of direct-LED pumping as an alternative to direct-diode or flashlamp pumping. LEDs emitting either at 460 or 810 nm were used to pump an uncooled Ce:Nd:YAG laser rod (at 30-Hz repetition rate for tens of seconds). Pumping at 460 nm was made possible by the Ce(3+) co-dopant that enables transfer of excitations near to Nd(3+) ions in the YAG lattice. Comparison of these two pumping schemes has allowed for a thorough analysis of the performance and efficiency of this laser system. QCW output energies as high as 18 mJ/pulse are reported, which to the best of our knowledge is the highest output pulse energy achieved by an LED-pumped solid-state laser to date. PMID:26125364

  4. Applications for reactor-pumped lasers

    SciTech Connect

    Lipinski, R.J.; McArthur, D.A.

    1994-10-01

    Nuclear reactor-pumped lasers (RPLs) have been developed in the US by the Department of Energy for over two decades, with the primary research occurring at Sandia National Laboratories and Idaho National Engineering Laboratory. The US program has experimentally demonstrated reactor-pumped lasing in various mixtures of xenon, argon, neon, and helium at wavelengths of 585, 703, 725, 1,271, 1,733, 1,792, 2,032, 2,630, 2,650, and 3,370 nm with intrinsic efficiency as high as 2.5%. The major strengths of a reactor-pumped laser are continuous high-power operation, modular construction, self-contained power, compact size, and a variety of wavelengths (from visible to infrared). These characteristics suggest numerous applications not easily accessible to other laser types. The continuous high power of an RPL opens many potential manufacturing applications such as deep-penetration welding and cutting of thick structures, wide-area hardening of metal surfaces by heat treatment or cladding application, wide-area vapor deposition of ceramics onto metal surfaces, production of sub-micron sized particles for manufacturing of ceramics, and 3-D ceramic lithography. In addition, a ground-based RPL could beam its power to space for such activities as illuminating geosynchronous communication satellites in the earth`s shadow to extend their lives, beaming power to orbital transfer vehicles, removing space debris, and providing power (from earth) to a lunar base during the long lunar night.

  5. Optically (solar) pumped oxygen-iodine lasers

    NASA Astrophysics Data System (ADS)

    Danilov, O. B.; Zhevlakov, A. P.; Yur'ev, M. S.

    2014-07-01

    We present the results of theoretical and experimental studies demonstrating the possibility of developing an oxygen-iodine laser (OIL) with direct optical pumping of molecular oxygen involving inter-molecular interaction with charge transfer from donor molecule (buffer gas) to acceptor molecule (oxygen). This interaction lifts degeneracy of the lower energy states of molecular oxygen and increases its absorption cross section in the visible spectral region and the UV Herzberg band, where high quantum yield of singlet oxygen is achieved (QY ˜ 1 and QY ˜ 2, respectively) at the same time. A pulse-periodic optical pump sources with pulse energy of ˜50 kJ, pulse duration of ˜25 μs, and repetition rate of ˜10 Hz, which are synchronized with the mechanism of singlet oxygen generation, are developed. This allows implementation of a pulse-periodic oxygen-iodine laser with an efficiency of ˜25%, optical efficiency of ˜40%, and parameter L/ T ˜ 1/1.5, where T is the thermal energy released in the laser active medium upon generation of energy L. It is demonstrated that, under direct solar pumping of molecular oxygen, the efficiency parameter of the OIL can reach L/ T ˜ 1/0.8 in a wide range of scaling factors.

  6. Grating THz laser with optical pumping

    NASA Astrophysics Data System (ADS)

    Khoury, Jed; Haji-saeed, Bahareh; Woods, Charles; Kierstead, John

    2010-04-01

    In this paper, we present a design for a widely tunable solid-state optically and electrically pumped THz laser based on the Smith-Purcell free-electron laser. In the free-electron laser, an energetic electron beam pumps a metallic grating to generate surface plasmons. Our solid-state optically pumped design consists of a thin layer of dielectic, such as SiNx, sandwiched between a corrugated structure and a thin metal or semiconductor layer. The lower layer is for current streaming, and replaces the electron beam in the original design. The upper layer consists of one micro-grating for coupling the electromagnetic field in, another for coupling out, and a nano-grating for coupling with the current in the lower layer for electromagnetic field generation. The surface plasmon waves generated from the upper layer by an external electromagnetic field, and the lower layer by the applied current, are coupled. Emission enhancement occurs when the plasmonic waves in both layers are resonantly coupled.

  7. Efficient flashlamp-pumped IBr laser

    NASA Technical Reports Server (NTRS)

    Zapata, L. E.; De Young, R. J.

    1985-01-01

    The operating characteristics and scaling parameters of a flashlamp-pumped, 4-m-long IBr laser were investigated to further evaluate its potential as a solar-pumped laser. A peak power of 3 kW/sq cm at 2.7 microns was achieved at 4-Torr IBr pressure. A gain of 0.07 per m was measured at a maximum capacitor discharge energy of 4 kJ. The threshold input power necessary for lasing was found to decrease by a factor of 4 and the laser pulse width increased fourfold as the active gain length was increased from 1 to 4 m. A maximum pulse width of 120 microseconds was achieved with 10-Torr argon diluent added to 4-Torr IBr. Quenching of the excited state by the parent molecule was shown to be unimportant for pressures less than 4-Torr IBr. An intrinsic efficiency in the range of 12 percent has been measured for flashlamp-pumped IBr.

  8. A blackbody radiation-pumped CO2 laser experiment

    NASA Astrophysics Data System (ADS)

    Christiansen, W. H.; Insuik, R. J.; Deyoung, R. J.

    1982-09-01

    Thermal radiation from a high temperature oven was used as an optical pump to achieve lasing from CO2 mixtures. Laser output as a function of blackbody temperature and gas conditions is described. This achievement represents the first blackbody cavity pumped laser and has potential for solar pumping.

  9. A high-repetition rate scheme for synchrotron-based picosecond laser pump/x-ray probe experiments on chemical and biological systems in solution

    SciTech Connect

    Lima, Frederico A.; Milne, Christopher J.; Amarasinghe, Dimali C. V.; Rittmann-Frank, Mercedes Hannelore; Veen, Renske M. van der; Reinhard, Marco; Pham, Van-Thai; Karlsson, Susanne; Mourik, Frank van; Chergui, Majed; Johnson, Steven L.; Grolimund, Daniel; Borca, Camelia; Huthwelker, Thomas; Janousch, Markus; Abela, Rafael

    2011-06-15

    We present the extension of time-resolved optical pump/x-ray absorption spectroscopy (XAS) probe experiments towards data collection at MHz repetition rates. The use of a high-power picosecond laser operating at an integer fraction of the repetition rate of the storage ring allows exploitation of up to two orders of magnitude more x-ray photons than in previous schemes based on the use of kHz lasers. Consequently, we demonstrate an order of magnitude increase in the signal-to-noise of time-resolved XAS of molecular systems in solution. This makes it possible to investigate highly dilute samples at concentrations approaching physiological conditions for biological systems. The simplicity and compactness of the scheme allows for straightforward implementation at any synchrotron beamline and for a wide range of x-ray probe techniques, such as time-resolved diffraction or x-ray emission studies.

  10. Progress in high-energy-class diode laser pump sources

    NASA Astrophysics Data System (ADS)

    Crump, P.; Frevert, C.; Bugge, F.; Knigge, S.; Erbert, G.; Tränkle, G.; Pietrzak, A.; Hüslewede, R.; Zorn, M.; Sebastian, J.; Lotz, J.; Fassbender, W.; Neukum, J.; Körner, J.; Hein, J.; Töpfer, T.

    2015-03-01

    A new generation of diode-pumped high-energy-class solid-state laser facilities is in development that generate multijoule pulse energies at around 10 Hz. Currently deployed quasi-continuous-wave (QCW) diode lasers deliver average inpulse pump powers of around 300 W per bar. Increased power-per-bar helps to reduce the system size, complexity and cost per Joule and the increased pump brilliance also enables more efficient operation of the solid state laser itself. It has been shown in recent studies, that optimized QCW diode laser bars centered at 940…980 nm can operate with an average in-pulse power of > 1000 W per bar, triple that of commercial sources. When operated at pulsed condition of 1 ms, 10 Hz, this corresponds to > 1 J/bar. We review here the status of these high-energy-class pump sources, showing how the highest powers are enabled by using long resonators (4…6 mm) for improved cooling and robustly passivated output facets for high reliability. Results are presented for prototype passively-cooled single bar assemblies and monolithic stacked QCW arrays. We confirm that 1 J/bar is sustained for fast-axis collimated stacks with a bar pitch of 1.7 mm, with narrow lateral far field angle (< 12° with 95% power) and spectral width (< 12 nm with 95% power). Such stacks are anticipated to enable Joule/bar pump densities to be used near-term in commercial high power diode laser systems. Finally, we briefly summarize the latest status of research into bars with higher efficiencies, including studies into operation at sub-zero temperatures (-70°C), which also enables higher powers and narrower far field and spectra.

  11. Advanced solar energy conversion. [solar pumped gas lasers

    NASA Technical Reports Server (NTRS)

    Lee, J. H.

    1981-01-01

    An atomic iodine laser, a candidate for the direct solar pumped lasers, was successfully excited with a 4 kW beam from a xenon arc solar simulator, thus proving the feasibility of the concept. The experimental set up and the laser output as functions of operating conditions are presented. The preliminary results of the iodine laser amplifier pumped with the HCP array to which a Q switch for giant pulse production was coupled are included. Two invention disclosures - a laser driven magnetohydrodynamic generator for conversion of laser energy to electricity and solar pumped gas lasers - are also included.

  12. Segment side-pumped Q-switched Nd:YAG laser.

    PubMed

    Wang, Wei; Fu, Chen; Hu, Zhenyue; Zhao, Qin; Gong, Mali

    2012-04-10

    In the design of conduction-cooled lasers, a side-pumped configuration is an attempt to solve the space conflict between pump and heat removal. The pump radiation always competes with the heat removal and mechanical support device for the lateral surface of a laser rod. This space conflict can be addressed by a segment side-pumped configuration in which circular laser diode arrays and heat-conducting rod holders alternate periodically along the length of the laser rod. This scheme permitted 11 Hz operation of a 190 mJ Q-switched laser at the wavelength of 1064 nm without the use of liquid cooling for both the laser rod and laser diode arrays and the corresponding optical-optical conversion efficiency of 23.1%. Thus, it has great potential to be used in compact and miniature laser systems. PMID:22505168

  13. High power tube solid-state laser with zigzag propagation of pump and laser beam

    NASA Astrophysics Data System (ADS)

    Savich, Michael

    2015-02-01

    A novel resonator and pumping design with zigzag propagation of pumping and laser beams permits to design an improved tube Solid State Laser (SSL), solving the problem of short absorption path to produce a high power laser beam (100 - 1000kW). The novel design provides an amplifier module and laser oscillator. The tube-shaped SSL includes a gain element fiber-optically coupled to a pumping source. The fiber optic coupling facilitates light entry at compound Brewster's angle of incidence into the laser gain element and uses internal reflection to follow a "zigzag" path in a generally spiral direction along the length of the tube. Optics are arranged for zigzag propagation of the laser beam, while the cryogenic cooling system is traditional. The novel method of lasing uses advantages of cylindrical geometry to reach the high volume of gain medium with compactness and structural rigidity, attain high pump density and uniformity, and reach a low threshold without excessive increase of the temperature of the crystal. The design minimizes thermal lensing and stress effects, and provides high gain amplification, high power extraction from lasing medium, high pumping and lasing efficiency and a high beam quality.

  14. Nuclear-driven flashlamp pumping of the atomic iodine laser

    SciTech Connect

    Miley, G.H.

    1992-03-01

    This report is a study of the atomic iodine laser pumped with nuclear- excited XeBr fluorescence. Preliminary experiments, conducted in the TRIGA reactor investigated the fluorescence of the excimer XeBr under nuclear pumping with {sup 10}B and {sup 3}He, for use as a flashlamp gas to stimulate the laser. These measurements included a determination of the fluorescence efficiency (light emitted in the wavelength region of interest, divided by energy deposited in the gas) of XeBr under nuclear pumping, with varying excimer mixtures. Maximum fluorescence efficiencies were approximately 1%. In order to better understand XeBr under nuclear excitation, a kinetics model of the system was prepared. The model generated the time-dependant concentrations of 20 reaction species for three pulse sizes, a TRIGA pulse, a fast burst reactor pulse, and an e-beam pulse. The modeling results predicted fluorescence efficiencies significantly higher (peak efficiencies of approximately 10%) than recorded in the fluorescence experiments. The cause of this discrepancy was not fully determined. A ray tracing computer model was also prepared to evaluate the efficiency with which nuclear-induced fluorescence generated in one cavity of a laser could be coupled into another cavity containing an iodine lasant. Finally, an experimental laser cell was constructed to verify that nuclear-induced XeBr fluorescence could be used to stimulate a laser. Lasing was achieved at 1.31 micron in the TRIGA using C{sub 3}F{sub 7}I, a common iodine lasant. Peak laser powers were approximately 20 mW. Measured flashlamp pump powers at threshold agreed well with literature values, as did lasant pressure dependency on laser operation.

  15. Efficiency of Nd laser materials with laser diode pumping

    NASA Technical Reports Server (NTRS)

    Barnes, Norman P.; Cross, Patricia L.; Skolaut, Milton W., Jr.; Storm, Mark E.

    1990-01-01

    For pulsed laser-diode-pumped lasers, where efficiency is the most important issue, the choice of the Nd laser material makes a significant difference. The absorption efficiency, storage efficiency, and extraction efficiency for Nd:YAG, Nd:YLF, Nd:GSGG, Nd:BEL, Nd:YVO4, and Nd:glass are calculated. The materials are then compared under the assumption of equal quantum efficiency and damage threshold. Nd:YLF is found to be the best candidate for the application discussed here.

  16. Thulium fiber laser-pumped mid-IR OPO

    NASA Astrophysics Data System (ADS)

    Creeden, Daniel; Jiang, Min; Budni, Peter A.; Ketteridge, Peter A.; Setzler, Scott D.; Young, York E.; McCarthy, John C.; Schunemann, Peter G.; Pollak, Thomas M.; Tayebati, Parviz; Chicklis, Evan P.

    2008-04-01

    Fiber lasers are advancing rapidly due to their ability to generate stable, efficient, and diffraction-limited beams with significant peak and average powers. This is of particular interest as fibers provide an ideal pump source for driving parametric processes. Most nonlinear optical crystals which provide phase-matching to the mid-IR at commercially available fiber pump wavelengths suffer from high absorption above 4μm, resulting in low conversion efficiencies in the 4-5μm spectral region. The nonlinear optical crystals which combine low absorption in this same spectral region with high nonlinear gain require pumping at longer wavelengths (typically >1.9μm). In this paper, we report a novel mid-IR OPO pumped by a pulsed thulium-doped fiber laser operating at 2-microns. The eyesafe thulium-fiber pump laser generates >3W of average power at >30kHz repetition rate with 15-30ns pulses in a near diffraction-limited beam. The ZnGeP II (ZGP) OPO produces tunable mid-IR output power in the 3.4-3.99μm (signal) and the 4.0-4.7μm (idler) spectral regions in both singly resonant (SRO) and doubly resonant (DRO) formats. The highest mid-IR output power achieved from this system was 800mW with 20% conversion efficiency at 40kHz. In a separate experiment, the 3W of 2-micron light was further amplified to the 20W level. This amplified output was also used to pump a ZGP OPO, resulting in 2W of output power in the mid-IR. To our knowledge, these are the first demonstrations of a fiber-pumped ZGP OPO.

  17. Satellite Power System (SPS) laser studies. Volume 2: Meteorological effects on laser beam propagation and direct solar pumped lasers for the SPS

    NASA Technical Reports Server (NTRS)

    Beverly, R. E., III

    1980-01-01

    The primary emphasis of this research activity was to investigate the effect of the environment on laser power transmission/reception from space to ground. Potential mitigation techniques to minimize the environment effect by a judicious choice of laser operating parameters was investigated. Using these techniques, the availability of power at selected sites was determined using statistical meteorological data for each site.

  18. Power scaling of semiconductor laser pumped Praseodymium-lasers

    NASA Astrophysics Data System (ADS)

    Richter, A.; Heumann, E.; Huber, G.; Ostroumov, V.; Seelert, W.

    2007-04-01

    We report on efficient lasing of Pr-doped fluoride materials with cw output powers up to 600 mW in the visible spectral range. Praseodymium doped LiYF4 and LiLuF4 crystals were pumped either by an intracavity frequency doubled optically pumped semiconductor laser with output powers up to 1.6 W and nearly diffraction limited beam quality or by a multimode GaN-laser diode with an output power of about 370 mW. Furthermore, intracavity frequency doubling of the red Pr-laser radiation to 320 nm reaching output powers of more than 360 mW with a conversion efficiency of 61% and an optical-to-optical efficiency of 22% are presented.

  19. A Kinetic Plasma-Pumped Rare Gas Laser

    NASA Astrophysics Data System (ADS)

    Parsey, Guy; Güçlü, Yaman; Verboncoeur, John; Christlieb, Andrew

    2015-09-01

    Extending from diode-pumped alkali vapor lasers (DPAL), Han and Heaven have shown that rare gas metastable states, np5 (n + 1) s[ 3 / 2 ] 2 , can operate as the base of a three-level laser with excition of the (n + 1) s --> (n + 1) p transitions. Though both the rare gas lasers (RGL) and DPALs can be excited with incoherent optical pumping, RGLs do not suffer from the highly reactive behavior of alkali metals. Since metastable populations are maintained via electric discharge, we propose using a tuned electron energy distribution function (EEDF) to modify RGL efficiencies and drive the population inversion. The EEDF is maintained by the discharge along with the introduction of electron sources. Using our kinetic global modeling framework (KGMf) and three gas systems (helium buffered argon and krypton along with pure argon), we first validate the intracavity intensity laser model and then generate gain and energy efficiency baselines for each system. Parameter scanning methods are then used to find optimized EEDFs and system parameters for metastable production, generation of a lasing population inversion, and increasing RGL operation efficiencies. Finally, we determine if an RGL can operate without optical pumping. Supported by AFOSR and a MSU Strategic Partnership Grant

  20. Amplified spontaneous emission in solar-pumped iodine laser

    NASA Technical Reports Server (NTRS)

    Cho, Yong S.; Hwang, In H.; Han, Kwang S.; Lee, Ja H.

    1992-01-01

    The amplified spontaneous emission (ASE) from a long pulse, solar-simulating radiation pumped iodine laser amplifier is studied. The ASE threshold pump intensity is almost proportional to the inverse of the laser gain length when the gas pressure is constant in the laser tube.

  1. Flow tube used to cool solar-pumped laser

    NASA Technical Reports Server (NTRS)

    1968-01-01

    A flow tube has been designed and constructed to provide two major functions in the application of a laser beam for transmission of both sound and video. It maintains the YAG laser at the proper operating temperature of 300 degrees K under solar pumping conditions, and it serves as a pump cavity for the laser crystal.

  2. a Blackbody-Pumped Carbon Dioxide Laser

    NASA Astrophysics Data System (ADS)

    Insuik, Robin Joy

    A proof of concept experiment has been carried out to demonstrate the feasibility of using blackbody radiation to pump a gas laser. Building on earlier experiments in which optical gain was measured in a CO(,2) laser mixture exposed to blackbody radiation at a temperature of 1500(DEGREES)K, continuous wave oscillation of CO(,2) has been achieved, for the first time, using radiation from a blackbody cavity as the pump source. This was made possible by actively cooling the laser mixture as it was exposed to the radiation field of an electrically heated oven. Output power measurements are presented from a series of experiments using mixtures of CO(,2), He, and Ar. Maximum output power was obtained with a 20%CO(,2) - 15%He- 65%Ar mixture at pressures around 6-10 Torr. The output power was found to vary greatly with the gas temperature and the blackbody temperature. By varying these parameters output powers up to 8 mW have been achieved. The effects of the buffer gas are also shown to be important. Based on the experimental results, it is believed that the buffer gas is needed to inhibit diffusion of the excited species out of the laser mode volume. This diffusion leads to deactivation at the walls. Adding more CO(,2) results in a decrease in output power, indicating that the gas has a finite optical depth and the mode volume is not pumped if too much CO(,2) is present. A model which incorporates these effects is presented. The predicted small signal gains and powers based on this model adequately match the trends observed experimentally.

  3. Improving pumping system efficiency at coal plants

    SciTech Connect

    Livoti, W.C.; McCandless, S.; Poltorak, R.

    2009-03-15

    The industry must employ ultramodern technologies when building or upgrading power plant pumping systems thereby using fuels more efficiently. The article discusses the uses and efficiencies of positive displacement pumps, centrifugal pumps and multiple screw pumps. 1 ref., 4 figs.

  4. Tunable mid-IR parametric conversion system pumped by a high-average-power picosecond Yb:YAG thin-disk laser

    NASA Astrophysics Data System (ADS)

    Novák, Ondřej; Miura, Taisuke; Smrž, Martin; Huynh, Jaroslav; Severová, Patricie; Endo, Akira; Mocek, TomáÅ.¡

    2014-05-01

    The mid-IR wavelength range has gained increased interest due to its applications in gas sensing, medicine, defense, and others. Optical parametric devices play an important role in the generation of radiation in the mid-IR. Low thermal load of nonlinear crystals promises high average power outputs if powerful pump laser is available. We have developed 75-W average power pump laser operating at 100 kHz repetition rate. The pulses of Yb-fiber laser oscillator at 1030-nm wavelength are stretched by a chirped volume Bragg grating from 5 ps to 180 ps and inserted into a cavity of regenerative amplifier with an Yb:YAG thin-disk. The amplified pulses are compressed by a chirped volume Bragg grating with an 88% efficiency. We have proposed a wavelength conversion system generating picosecond pulses tunable between 2 and 3 μm. The seed signal radiation is acquired by the optical parametric generation in the first nonlinear crystal. Signal pulse energy is increased in the subsequent optical parametric amplifiers. Each amplification stage consists of a crystal pair in the walkoff compensating arrangement. The wavelength of the signal beam is tunable between 1.6 and 2.1 μm. The 2.1 - 3 μm tunable source will be the idler beam taken from the last amplification stage. Calculations show the output power of ten watt can be achieved for 100 W pump. The results of preliminary experiments with seeded optical parametric generation and subsequent amplification are presented and discussed.

  5. Multimode-diode-pumped gas (alkali-vapor) laser

    SciTech Connect

    Page, R H; Beach, R J; Kanz, V K

    2005-08-22

    We report the first demonstration of a multimode-diode-pumped gas laser--Rb vapor operating on the 795 nm resonance transition. Peak output of {approx}1 Watt was obtained using a volume-Bragg-grating stabilized pump diode array. The laser's output radiance exceeded the pump radiance by a factor greater than 2000. Power scaling (by pumping with larger diode arrays) is therefore possible.

  6. Pump power stability range of single-mode solid-state lasers with rod thermal lensing

    SciTech Connect

    De Silvestri, S.; La Porta, P.; Magni, V.

    1987-11-01

    The pump power stability range of solid-state laser resonators operating in the TEM/sub 00/ mode has been thoroughly investigated. It has been shown that, for a very general resonator containing intracavity optical systems, rod thermal lensing engenders a pump power stability range which is a characteristic parameter of laser material and pump cavity, but is independent of resonator configuration. Stability ranges have been calculated and critically discussed for Nd:YAG, Nd:Glasses, Nd:Cr:GSGG, and alexandrite. The independence of the pump power stability range from the resonator configuration has been experimentally demonstrated for a CW Nd:YAG laser.

  7. A kilowatt level diode-side-pumped QCW Nd:YAG ceramic laser

    NASA Astrophysics Data System (ADS)

    Li, C. Y.; Bo, Y.; Wang, B. S.; Tian, C. Y.; Peng, Q. J.; Cui, D. F.; Xu, Z. Y.; Liu, W. B.; Feng, X. Q.; Pan, Y. B.

    2010-12-01

    We demonstrate a kilowatt level Quasi-continuous-wave (QCW) diode-side-pumped Nd:YAG ceramic laser at 1064 nm. The laser system adopts a master oscillator power amplifier scheme (MOPA). The master oscillator contains two diode-pumped laser modules. Under the pump power of 2000 W, an output power of 686 W was obtained. After amplified by an identical ceramic laser module, a maximum output power of 1020 W was obtained under a total incident pump power of 3433 W, corresponding to an optical-optical conversion efficiency of 29.7%. At the maximal output power, the repetition frequency was measured to be 1 kHz and the pulse width was 114 μs. To the best of our knowledge, this is the first time to realize QCW side-pumped Nd:YAG ceramic laser system with output power above 1 kW.

  8. Multi-photon microscope driven by novel green laser pump

    NASA Astrophysics Data System (ADS)

    Marti, Dominik; Djurhuus, Martin; Jensen, Ole Bjarlin; Andersen, Peter E.

    2016-03-01

    Multi-photon microscopy is extensively used in research due to its superior possibilities when compared to other microscopy modalities. The technique also has the possibility to advance diagnostics in clinical applications, due to its capabilities complementing existing technology in a multimodal system. However, translation is hindered due to the high cost, high training demand and large footprint of a standard setup. We show in this article that minification of the setup, while also reducing cost and complexity, is indeed possible without compromising on image quality, by using a novel diode laser replacing the commonly used conventional solid state laser as the pump for the femtosecond system driving the imaging.

  9. Design of diode-pumped solid-state laser applied in laser fuses

    NASA Astrophysics Data System (ADS)

    Deng, FangLin; Zhang, YiFei

    2005-04-01

    The function of laser fuzes which are parts of certain weapon systems is to control the blasting height of warheads. Commonly the battle environment these weapon systems are confronted with is very complicated and the tactical demand for them is very rigor, so laser fuzes equipped for them must fulfill some special technical requirements, such as high repetition rate, long ranging scope, etc. Lasers are one of key components which constitute fuze systems. Whether designed lasers are advanced and reasonable will determine whether laser fuzes can be applied in these weapon systems or not. So we adopt the novel technology of diode-pumped solid-state laser (DPSSL) to design lasers applied in fuzes. Nd:YVO4 crystal is accepted as gain material, which has wide absorption band and large absorption efficient for 808nm pumping laser. As warhead's temperature is usually very high, wider absorption band is beneficial to reduce the influence of temperature fluctuation. Passive Q-switching with Cr4+:YAG is used to reduce the power consumption farthest. Design the end-pumped microchip sandwich-architecture to decrease lasers' size and increase the reliability, further it's advantageous to produce short pulses and increase peak power of lasers. The designed DPSSL features small size and weight, high repetition rate and peak power, robustness, etc. The repetition rate is expected to reach 1 kHz; peak power will exceed 300 kW; pulse width is only 5 ns; and divergence angle of laser beams is less than 5 mrad. So DPSSL is suitable for laser fuzes as an emitter.

  10. Optical pumping of generalized laser active materials.

    PubMed

    Fry, F H

    1967-11-01

    Results are presented of a computer-based study on the rate of excitation in the active cores of two types of optically pumped lasers as a function of a number of parameters of the active core. The absorption bands of the active materials are generated by Lorentzian and Gaussian functions. The excitation rate of the active core is proportional to the width of the absorption band at all depths of penetration. The plots of excitation rate as a function of frequency show curves similar to line reversal spectra and emphasize the importance of excitation some distance from the center of the absorption band in the slab model. In the cylindrical model, this wing pumping is even more important due to focusing. The effect of refractive index on the excitation rate is also described. PMID:20062337

  11. Fissioning uranium plasmas and nuclear-pumped lasers

    NASA Technical Reports Server (NTRS)

    Schneider, R. T.; Thom, K.

    1975-01-01

    Current research into uranium plasmas, gaseous-core (cavity) reactors, and nuclear-pumped lasers is discussed. Basic properties of fissioning uranium plasmas are summarized together with potential space and terrestrial applications of gaseous-core reactors and nuclear-pumped lasers. Conditions for criticality of a uranium plasma are outlined, and it is shown that the nonequilibrium state and the optical thinness of a fissioning plasma can be exploited for the direct conversion of fission fragment energy into coherent light (i.e., for nuclear-pumped lasers). Successful demonstrations of nuclear-pumped lasers are described together with gaseous-fuel reactor experiments using uranium hexafluoride.

  12. DOE reactor-pumped laser program

    SciTech Connect

    Felty, J.R.; Lipinski, R.J.; McArthur, D.A.; Pickard, P.S.

    1993-12-31

    FALCON is a high-power, steady-state, nuclear reactor-pumped laser (RPL) concept that is being developed by the Department of Energy. The FALCON program has experimentally demonstrated reactor-pumped lasing in various mixtures of xenon, argon, neon, and helium at at wavelengths of 585, 703, 725, 1271, 1733, 1792, 2032, 2630, 2650, and 3370 nm with intrinsic efficiency as high as 2.5%. The major strengths of a reactor-pumped laser are continuous high-power operation, modular construction, self-contained power, compact size, and a variety of wavelengths (from visible to infrared). These characteristics suggest numerous applications not easily accessible to other laser types. A ground-based RPL could beam its power to space for such activities as illuminating geosynchronous communication satellites in the earth`s shadow to extend their lives, beaming power to orbital transfer vehicles, removing space debris, and providing power (from earth) to a lunar base during the long lunar night. The compact size and self-contained power also makes an RPL very suitable for ship basing so that power-beaming activities could be situated around the globe. The continuous high power of an RPL opens many potential manufacturing applications such as deep-penetration welding and cutting of thick structures, wide-area hardening of metal surfaces by heat treatment or cladding application, wide-area vapor deposition of ceramics onto metal surfaces, production of sub-micron sized particles for manufacturing of ceramics, wide-area deposition of diamond-like coatings, and 3-D ceramic lithography.

  13. DOE reactor-pumped laser program

    SciTech Connect

    Felty, J.R.; Lipinski, R.J.; McArthur, D.A.; Pickard, P.S.

    1994-12-31

    FALCON is a high-power, steady-state, nuclear reactor-pumped laser (RPL) concept that is being developed by the Department of Energy. The FALCON program has experimentally demonstrated reactor-pumped lasing in various mixtures of xenon, argon, neon, and helium at wavelengths of 585, 703, 725, 1271, 1733, 1792, 2032, 2630, 2650, and 3370 nm with intrinsic efficiency as high as 2.5%. The major strengths of a reactor-pumped laser are continuous highpower operation, modular construction, self-contained power, compact size, and a variety of wavelengths (from visible to infrared). These characteristics suggest numerous applications not easily accessible to other laser types. A ground-based RPL could beam its power to space for such activities as illuminating geosynchronous communication satellites in the earth`s shadow to extend their lives, beaming power to orbital transfer vehicles, removing space debris, and providing power (from earth) to a lunar base during the long lunar night. The compact size and self-contained power also makes an RPL very suitable for ship basing so that power-beaming activities could be situated around the globe. The continuous high power of an RPL opens many potential manufacturing applications such as deep-penetration welding and cutting of thick structures, wide-area hardening of metal surfaces by heat treatment or cladding application, wide-area vapor deposition of ceramics onto metal surfaces, production of sub-micron sized particles for manufacturing of ceramics, wide-area deposition of diamond-like coatings, and 3-D ceramic lithography.

  14. DOE reactor-pumped laser program

    NASA Astrophysics Data System (ADS)

    Felty, James R.; Lipinski, Ronald J.; McArthur, David A.; Pickard, Paul S.

    1994-05-01

    FALCON is a high-power, steady-state, nuclear reactor-pumped laser (RPL) concept that is being developed by the Department of Energy. The FALCON program has experimentally demonstrated reactor-pumped lasing in various mixtures of xenon, argon, neon, and helium at wavelengths of 585, 703, 725, 1271, 1733, 1792, 2032, 2630, 2650, and 3370 nm with intrinsic efficiency as high as 2.5%. The major strengths of a reactor-pumped laser are continuous high-power operation, modular construction, self-contained power, compact size, and a variety of wavelengths (from visible to infrared). These characteristics suggest numerous applications not easily accessible to other laser types. A ground-based RPL could beam its power to space for such activities as illuminating geosynchronous communication satellites in the earth's shadow to extend their lives, beaming power to orbital transfer vehicles, removing space debris, and providing power (from earth) to a lunar base during the long lunar night. The compact size and self-contained power also makes an RPL very suitable for ship basing so that power-beaming activities could be situated around the globe. The continuous high power of an RPL opens many potential manufacturing applications such as deep-penetration welding and cutting of thick structures, wide-area hardening of metal surfaces by heat treatment or cladding application, wide-area vapor deposition of ceramics onto metal surfaces, production of sub-micron sized particles for manufacturing of ceramics, wide-area deposition of diamond- like coatings, and 3-D ceramic lithography.

  15. High-power CW diode-laser-array-pumped solid-state lasers and efficient nonlinear optical frequency

    NASA Astrophysics Data System (ADS)

    Shine, Robert J.; Byer, Robert L.

    1994-01-01

    During the interim period of this bridging contract, we have continued to work on the development of high-power cw diode-laser-array-pumped solid-state lasers. Towards that end, we have built lower power lasers in order to test individual components needed for the high-power laser, specifically we have built a 1 watt ring laser and a 5 watt slab laser. The 1 watt laser was used to study the injection locking process while assembling all the necessary electronics. We have demonstrated that it is possible to injection lock a diode-pumped laser using a single piezo-mounted mirror due to the lower intrinsic laser noise compared to an arc-lamp-pumped system. This allows us to optimize the injection locking servo loop and build a more stable locking system. The 5 watt laser was used as a test bed to find a practical way to mount the slab laser while minimizing the losses that occur at the total internal reflection (TIR) points in the slab. After trying many different means of protecting the TIR surfaces, we found that a new product from DuPont, Teflon AF 1600, has all the properties needed to provide a low loss protective coating. Using this material, the laser had a cavity loss of below 2%, which allowed for efficient operation of the laser in a side-pumped design. This laser produced 5 watts of output power with a slope efficiency near 20%.

  16. Heat Pumping in Nanomechanical Systems

    NASA Astrophysics Data System (ADS)

    Chamon, Claudio; Mucciolo, Eduardo R.; Arrachea, Liliana; Capaz, Rodrigo B.

    2011-04-01

    We propose using a phonon pumping mechanism to transfer heat from a cold to a hot body using a propagating modulation of the medium connecting the two bodies. This phonon pump can cool nanomechanical systems without the need for active feedback. We compute the lowest temperature that this refrigerator can achieve.

  17. Thin-Film Evaporative Cooling for Side-Pumped Laser

    NASA Technical Reports Server (NTRS)

    Stewart, Brian K. (Inventor)

    2010-01-01

    A system and method are provided for cooling a crystal rod of a side-pumped laser. A transparent housing receives the crystal rod therethrough so that an annular gap is defined between the housing and the radial surface of the crystal rod. A fluid coolant is injected into the annular gap such the annular gap is partially filled with the fluid coolant while the radial surface of the crystal rod is wetted as a thin film all along the axial length thereof.

  18. A multi-pass pumping scheme for thin disk lasers with good anti-disturbance ability.

    PubMed

    Huang, Yan; Zhu, Xiao; Zhu, Guangzhi; Shang, Jianli; Wang, Hailin; Qi, Lijun; Zhu, Changhong; Guo, Fei

    2015-02-23

    A multi-pass pumping scheme for thin disk lasers consisting of dual parabolic mirrors with conjugated relationship is presented. The anti-disturbance ability of pumping is analyzed by ray tracing method under different kinds of disturbances. Both theoretical and experiment results show that disturbances in this system won't lead to a misalignment of each pumping spot, but only the position of superposed pumping spot on disk crystal will be changed. Compared with the multi-pass pumping scheme consisting of parabolic mirror and folding prisms, this pumping scheme has a better anti-disturbance ability. PMID:25836497

  19. Rhodamine 6G laser pumped by cathodoluminescence

    SciTech Connect

    Lisitsyn, V.M.; Lyakh, G.O.; Orlovskii, V.M.; Osipov, V.V.; Urbazaev, M.N.

    1984-08-01

    Cathodoluminescence from a CdS crystal, generated by the action of high-power short-duration electron beam pulses was used to pump a rhodamine 6G (R6G) laser. Measurements were made of the energy spectrum of the electrons in the beam exciting the CdS crystal, of the cathodoluminescence spectrum of CdS, of the absorption and emission spectra of the dye, and also of the time characteristics of the cathodoluminescence and of the dye laser radiation. When the electron beam incident on the crystal was characterized by a current of 500 A and duration 8 nsec at half-height, the radiation pulses emitted by R6G had an energy of approx.1 mJ and the efficiency of generation of these pulses was approx.0.3%. OFF

  20. Wavefront curvature of an opticaly pumped waveguide laser

    SciTech Connect

    Tacke, M.

    1983-05-01

    The influence of inhomogeneous gain on the wavefront shape is discussed for waveguide lasers. As an example, the curvature of the EH(11) mode of an optically pumped FIR laser is computed, its influence on the output beam is discussed.

  1. Squeezed light from conventionally pumped multi-level lasers

    NASA Technical Reports Server (NTRS)

    Ralph, T. C.; Savage, C. M.

    1992-01-01

    We have calculated the amplitude squeezing in the output of several conventionally pumped multi-level lasers. We present results which show that standard laser models can produce significantly squeezed outputs in certain parameter ranges.

  2. An experimental investigation of (UF-235)6 fission nuclear-pumped lasers

    NASA Technical Reports Server (NTRS)

    Miley, G. H.

    1979-01-01

    A UF6 handling system was designed for use in conjunction with the existing nuclear-pumped laser vacuum system at a nuclear reactor laboratory to perform the experiments described above. A modification to separate the gas fill system from the vacuum system and thus greatly reduce its volume is described as well as operating procedures for the first controlled nuclear pumping experiments with UF6 vapor contained in the laser cell.

  3. Solar-pumped Er,Tm,Ho:YAG laser

    SciTech Connect

    Benmair, R.M.J.; Kagan, J.; Kalisky, Y.; Noter, Y.; Oron, M.; Shimony, Y.; Yogev, A. )

    1990-01-01

    Direct solar illumination was used to pump a 5-mm-diameter 62-mm exposed-length rod of Er,Tm,Ho:YAG to achieve a quasi-cw lasing of the Ho ion at an average power of 12 W. The solar radiation was chopped at a 20% duty cycle to avoid overloading of the cooling system. The peak power output was more than 65 W during the chopper's open times. The slope efficiency is 3.8%, and the threshold input energy is approximately 100 W. The laser was operated for long times (up to hours) while maintaining its performance. This is, to our knowledge, the first directly solar-pumped laser operating at 77 K.

  4. Tuning laser output characteristics of a pyrotechnically pumped free-running Nd:YAG laser in terms of pumping kinetics

    NASA Astrophysics Data System (ADS)

    Kang, Xiaoli; Yang, Fan; Luo, Jiangshan; Tang, Yongjian

    2015-02-01

    Using light radiation directly produced by combustion of some pyrotechnics as pumping sources of solid state lasers is a potentially effective way to obtain compact and high energy lasers. Kinetics of this kind of pumping is studied in terms of pulse energy and pulse time characteristics as well as laser output energy. Pumping kinetics is turned through changing fabrication methods of the pumping modules. It was found that the useful light energy and pulse time for the pyrotechnic pumping light showed opposite changing trend. Compressing pulse duration from 45 ms to about 10 ms would simultaneously cause 20%~ 50% decreases in useful light radiation energy. However, the laser output energy produced by these pumping sources only had a variation 9%, ranging from 427 mJ to 468 mJ. Reasons were related to the decrease in fluorescence loss in pumping energy below the threshold for the pyrotechnic modules having shorter pulse duration but higher radiation power.

  5. Dual-Wavelength Internal-Optically-Pumped Semiconductor Laser Diodes

    NASA Astrophysics Data System (ADS)

    Green, Benjamin

    Dual-wavelength laser sources have various existing and potential applications in wavelength division multiplexing, differential techniques in spectroscopy for chemical sensing, multiple-wavelength interferometry, terahertz-wave generation, microelectromechanical systems, and microfluidic lab-on-chip systems. In the drive for ever smaller and increasingly mobile electronic devices, dual-wavelength coherent light output from a single semiconductor laser diode would enable further advances and deployment of these technologies. The output of conventional laser diodes is however limited to a single wavelength band with a few subsequent lasing modes depending on the device design. This thesis investigates a novel semiconductor laser device design with a single cavity waveguide capable of dual-wavelength laser output with large spectral separation. The novel dual-wavelength semiconductor laser diode uses two shorter- and longer-wavelength active regions that have separate electron and hole quasi-Fermi energy levels and carrier distributions. The shorter-wavelength active region is based on electrical injection as in conventional laser diodes, and the longer-wavelength active region is then pumped optically by the internal optical field of the shorter-wavelength laser mode, resulting in stable dual-wavelength laser emission at two different wavelengths quite far apart. Different designs of the device are studied using a theoretical model developed in this work to describe the internal optical pumping scheme. The carrier transport and separation of the quasi-Fermi distributions are then modeled using a software package that solves Poisson's equation and the continuity equations to simulate semiconductor devices. Three different designs are grown using molecular beam epitaxy, and broad-area-contact laser diodes are processed using conventional methods. The modeling and experimental results of the first generation design indicate that the optical confinement factor of the

  6. Biological research by optically pumped far infrared lasers

    NASA Astrophysics Data System (ADS)

    Zhengyu, Mi

    1989-05-01

    The FIR breeding for paddy rice, black bean and wheat, the chlorophyll mutation of paddy rice induced by optically pumped FIR laser, etc., are presented. The results of SDS electrophoresis analysis of soluble proteins of Drosophita melanrgaster irradiated by optically pumped FIR laser are described and discussed.

  7. Vanadium-pumped titanium x-ray laser

    DOEpatents

    Nilsen, Joseph

    1992-01-01

    A resonantly photo-pumped x-ray laser (10) is formed of a vanadium (12) and titanium (14) foil combination (16) that is driven by two beams (18, 20) of intense line focused (22, 24) optical laser radiation. Ground state neon-like titanium ions (34) are resonantly photo-pumped by line emission from fluorine-like vanadium ions (32).

  8. Vanadium-pumped titanium x-ray laser

    DOEpatents

    Nilsen, J.

    1992-05-26

    A resonantly photo-pumped x-ray laser is formed of a vanadium and titanium foil combination that is driven by two beams of intense line focused optical laser radiation. Ground state neon-like titanium ions are resonantly photo-pumped by line emission from fluorine-like vanadium ions. 4 figs.

  9. CW YVO4:Er Laser with Resonant Pumping

    NASA Astrophysics Data System (ADS)

    Gorbachenya, K. N.; Kisel, V. E.; Yasukevich, A. S.; Matrosov, V. N.; Tolstik, N. A.; Kuleshov, N. V.

    2015-05-01

    The lasing characteristics of a YVO4:Er laser with resonant pumping in the 1.5-1.6 μm range are studied. Lasing is obtained at λ = 1603 nm with a differential efficiency of up to 61%. YVO4:Er crystals are found to offer promise for use in efficient resonantly (in-band) pumped lasers.

  10. CO.sub.2 optically pumped distributed feedback diode laser

    DOEpatents

    Rockwood, Stephen D.

    1980-01-01

    A diode laser optically pumped by a CO.sub.2 coherent source. Interference fringes generated by feeding the optical pumping beam against a second beam, periodically alter the reflectivity of the diode medium allowing frequency variation of the output signal by varying the impingent angle of the CO.sub.2 laser beams.

  11. Investigation of a pulsed dye laser under various pumping conditions

    SciTech Connect

    Nechaev, S.Y.

    1983-08-01

    An investigation was made of the influence of bilateral laser pumping in an almost longitudinal arrangement on the spectral and energy characteristics of a short-pulse laser utilizing rhodamine 6G. A considerable increase in efficiency over that for unilateral pumping was observed, together with a narrowing of the spectrum, in a dispersive resonator having a prism telescope and a grating.

  12. High power cooled mini-DIL pump lasers

    NASA Astrophysics Data System (ADS)

    Liang, Bo; Zayer, Nadhum; Chen, Bob; He, Dylan; Pliska, Tomas

    2009-11-01

    The miniature dual-inline (mini-DIL) pump laser becomes more attactive for compact optical amplifiers designs due to the advantage of smaller footprint, lower power consumption and lower cost. In this paper we report the development of a new generation of small form factor, high power "cooled" mini-DIL 980-nm pump lasers module for compact EDFA application.

  13. Linewidth-tunable laser diode array for rubidium laser pumping

    SciTech Connect

    Li Zhiyong; Tan Rongqing; Xu Cheng; Li Lin

    2013-02-28

    To optimise the pump source for a high-power diodepumped rubidium vapour laser, we have designed a laser diode array (LDA) with a narrowed and tunable linewidth and an external cavity formed by two volume Bragg gratings (VBGs). Through controlling the temperature differences between the two VBGs, the LDA linewidth, which was 1.8 nm before mounting the two VBGs, was tunable from 100 pm to 0.2 nm, while the output power changed by no more than 4 %. By changing simultaneously the temperature in both VBGs, the centre wavelength in air of the linewidth-tunable LDA was tunable from 779.40 nm to 780.05 nm. (control of laser radiation parameters)

  14. Double-beam, mode-controlling diode side-pumped Nd:YLF laser with near 60% efficiency

    NASA Astrophysics Data System (ADS)

    Deana, Alessandro M.; Wetter, Niklaus U.

    2015-02-01

    The double-beam, mode-controlling technique (DBMC) is a compact side-pumped laser design, very advantageous for systems based on active media with intermediate absorption cross section, such as Nd:YLiF4 (Nd:YLF). Recently, a record optical efficiency of 53.6% and 63.5% slope efficiency has been achieved for a Nd:YLF laser emitting at 1053 nm with diffraction limited beam quality. In this work we review our results using the DBMC design and present the latest achievements exploiting new ways to push the limit of this technique to higher pump powers. By narrowing down the laser emission bandwidth of the pump diode bar using a volume Bragg gratings (VBG) we increased the effective absorption cross section in the Nd:YLF crystal, improving the spatial overlap between pump and laser beam. With this setup the laser delivers 68 W peak fundamental mode output power at 115 W of QCW absorbed peak power, resulting near 60% of optical-to-optical efficiency which is, to the best of our knowledge, the highest efficiency ever reported for a Nd:YLF laser, considering even longitudinal pump schemes. The results reported here highlight the remarkable advantages of the side pumped DBMC laser scheme versus longitudinal pumped laser set-ups, showing that the efficiency of the side-pumped DBMC laser is not suppressed by its spatially weaker overlap between pump and laser mode and preserving single mode laser operation, even at high pump powers.

  15. Long-Lifetime Laser Materials For Effective Diode Pumping

    NASA Technical Reports Server (NTRS)

    Barnes, Norman P.

    1991-01-01

    Long quantum lifetimes reduce number of diodes required to pump. Pumping by laser diodes demonstrated with such common Nd laser materials as neodymium:yttrium aluminum garnet (Nd:YAG) and Nd:YLiF4, but such materials as Nd:LaF3, Nd:NaF.9YF3, and possibly Nd:YF3 more useful because of long lifetimes of their upper laser energy levels. Cost effectiveness primary advantage of solid-state laser materials having longer upper-laser-level lifetimes. Because cost of diodes outweighs cost of laser material by perhaps two orders of magnitude, cost reduced significantly.

  16. Single-frequency tunable laser for pumping cesium frequency standards

    SciTech Connect

    Zhuravleva, O V; Ivanov, Andrei V; Leonovich, A I; Kurnosov, V D; Kurnosov, K V; Chernov, Roman V; Shishkov, V V; Pleshanov, S A

    2006-08-31

    A single-frequency tunable laser for pumping the cesium frequency standard is studied. It is shown experimentally that the laser emits at a single frequency despite the fact that a few longitudinal modes of the external cavity fall within the reflection band of a fibre Bragg grating (FBG) written in the optical fibre. The laser wavelength can be tuned by varying the pump current of the laser, its temperature, and the FBG temperature. The laser linewidth does not exceed 2 MHz for 10 mW of output power. (lasers)

  17. Pump control system for windmills

    SciTech Connect

    Avery, D.E.

    1983-07-12

    A windmill control system is disclosed having lever means, for varying length of stroke of the pump piston, and a control means, responsive to the velocity of the wind to operate the lever means to vary the length of stroke and hence the effective displacement of the pump in accordance with available wind energy, with the control means having a sensing member separate from the windmill disposed in the wind and displaceable thereby in accordance with wind velocity.

  18. Pump control system for windmills

    DOEpatents

    Avery, Don E.

    1983-01-01

    A windmill control system having lever means, for varying length of stroke of the pump piston, and a control means, responsive to the velocity of the wind to operate the lever means to vary the length of stroke and hence the effective displacement of the pump in accordance with available wind energy, with the control means having a sensing member separate from the windmill disposed in the wind and displaceable thereby in accordance with wind velocity.

  19. Tunable excitation of mid-infrared optically pumped semiconductor lasers

    NASA Astrophysics Data System (ADS)

    Olafsen, Linda J.; Kunz, Jeremy; Ongstad, Andrew P.; Kaspi, Ron

    2013-01-01

    While conventional semiconductor lasers employ electrical injection for carrier excitation, optically pumped semiconductor lasers (OPSLs) have demonstrated high output powers and high brightness in the mid-infrared. An important consideration for optically pumped lasers is efficient absorption of the pump beam, which can be achieved through increasing the number of periods in the active region, by placing the active region in a cavity with an optical thickness of twice the pump wavelength between distributed Bragg reflectors (Optical Pumping Injection Cavity), or by periodically inserting the active quantum wells into an InGaAsSb waveguide designed to absorb the pump radiation (Integrated Absorber). A tunable optical pumping technique is utilized by which threshold intensities are minimized and efficiencies are maximized. The near-IR idler output of a Nd:YAG-pumped optical parametric oscillator (10 Hz, ~4 ns) is the tunable optical pumping source in this work. Results are presented for an OPSL with a type-II W active region embedded in an integrated absorber to enhance the absorption of the optical pump beam. Emission wavelengths range from 4.64 μm at 78 K to 4.82 μm at 190 K for optical pump wavelengths ranging from 1930-1950 nm. The effect of wavelength tuning is demonstrated and compared to single wavelength pumping (1940 nm) at a higher duty cycle (20- 30%). Comparisons are also made to other OPSLs, including a discussion of the characteristic temperature and high temperature performance of these devices.

  20. Reliable pump sources for high-energy class lasers

    NASA Astrophysics Data System (ADS)

    Wölz, Martin; Pietrzak, Agnieszka; Kindsvater, Alex; Wolf, Jürgen; Meusel, Jens; Hülsewede, Ralf; Sebastian, Jürgen

    2015-05-01

    High-energy class laser systems operating at high average power are destined to serve fundamental research and commercial applications. System cost is becoming decisive, and JENOPTIK supports future developments with the new range of 500 W quasi-continuous wave (QCW) laser diode bars. In response to different strategies in implementing high-energy class laser systems, pump wavelengths of 880 nm and 940 nm are available. The higher power output per chip increases array irradiance and reduces the size of the optical system, lowering system cost. Reliability testing of the 880 nm laser diode bar has shown 1 Gshots at 500 W and 300 μs pulse duration, with insignificant degradation. Parallel operation in eight-bar diode stacks permits 4 kW pulse power operation. A new high-density QCW package is under development at JENOPTIK. Cost and reliability being the design criteria, the diode stacks are made by simultaneous soldering of submounts and insulating ceramic. The new QCW stack assembly technology permits an array irradiance of 12.5 kW/cm². We present the current state of the development, including laboratory data from prototypes using the new 500 W laser diode in dense packaging.

  1. Continuous-wave seeded mid-IR parametric system pumped by the high-average-power picosecond Yb:YAG thin-disk laser

    NASA Astrophysics Data System (ADS)

    Novák, Ondřej; Smrž, Martin; Miura, Taisuke; Turčičová, Hana; Endo, Akira; Mocek, Tomáś

    2015-05-01

    Mid-IR wavelength range offers variety of interesting applications. Down-conversion in the optical parametric devices is promising to generate high average power mid-IR beam due to inherently low thermal load of the nonlinear crystals if a powerful and high quality pump beam is available. We developed 100 kHz pump laser of 100-W level average power. The stretched pulses of Yb-fiber laser oscillator at 1030 nm wavelength are injected into the regenerative amplifier with an Yb:YAG thin-disk. Diode pumping at zero phonon line at wavelength of 969 nm significantly reduces its thermal load and increases conversion efficiency and stability. We obtained the beam with power of 80 W and 2 ps compressed pulsewidth. We are developing a watt level mid-IR picosecond light source pumped by a beam of the thin disk regenerative amplifier. Part of the beam pumps PPLN, which is seeded by a continuous wave laser diode at 1.94 μm to decrease the generation threshold and determine the amplified spectrum. The 3 W pumping gave output of 30 mW, which is by up to two orders higher compared to unseeded operation. The gain of about 107 was achieved in the PPLN in the temporal window of the pump pulse. The spectrum and beam of the generated idler pulses in the mid-IR was measured. We obtained an amplified signal from the second stage with the KTP crystal. We expect watt level mid-IR output for initial 50-W pumping. The generation of longer wavelengths is discussed.

  2. Diode pumped alkali vapor lasers for high power applications

    NASA Astrophysics Data System (ADS)

    Zweiback, J.; Krupke, B.; Komashko, A.

    2008-02-01

    General Atomics has been engaged in the development of diode pumped alkali vapor lasers. We have been examining the design space looking for designs that are both efficient and easily scalable to high powers. Computationally, we have looked at the effect of pump bandwidth on laser performance. We have also looked at different lasing species. We have used an alexandrite laser to study the relative merits of different designs. We report on the results of our experimental and computational studies.

  3. Pump system characterization and reliability enhancement

    SciTech Connect

    Staunton, R.H.

    1997-09-01

    Pump characterization studies were performed at the Oak Ridge National Laboratory (ORNL) to review and analyze six years (1990 to 1995) of data from pump systems at domestic nuclear plants. The studies considered not only pumps and pump motors but also pump related circuit breakers and turbine drives (i.e., the pump system). One significant finding was that the number of significant failures of the pump circuit breaker exceeds the number of significant failures of the pump itself. The study also shows how regulatory code testing was designed for the pump only and therefore did not lead to the discovery of other significant pump system failures. Potential diagnostic technologies both experimental and mature, suitable for on-line and off-line pump testing were identified. The study does not select or recommend technologies but proposes diagnostic technologies and monitoring techniques that should be further evaluated/developed for making meaningful and critically needed improvements in the reliability of the pump system.

  4. Nuclear-pumped He/3/-Ar laser modeling

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Deyoung, R. J.; Harries, W. L.

    1979-01-01

    A first-order model of He(3)-Ar 1.79-micron laser is developed, compared to experimental results, and used to explain the qualitative features of this system. Results indicate that direct excitation of the argon upper level is at best very inefficient for population inversion. For argon concentrations which give the most efficient laser operation, the He-3(n,p)He-3(n,p)He-3 energy is used to produce atomic He ions that quickly convert into He molecular ions. These molecular ions subsequently form argon atomic ions through charge transfer. The dominant pumping mechanism is collisional-radiative recombination of the argon atomic ion and subsequent radiative cascading into the upper laser level.

  5. Recent nuclear pumped laser results. [gas mixtures and laser plasmas

    NASA Technical Reports Server (NTRS)

    Miley, G. H.; Wells, W. E.; Akerman, M. A.; Anderson, J. H.

    1976-01-01

    Recent direct nuclear pumped laser research has concentrated on experiments with three gas mixtures (Ne-N2, He-Ne-O2, and He-Hg). One mixture has been made to lase and gain has been achieved with the other two. All three of these mixtures are discussed with particular attention paid to He-Hg. Of interest is the 6150-angstroms ion transition in Hg(+). The upper state of this transition is formed directly by charge transfer and by Penning ionization.

  6. Mode locked Nd:YVO 4 laser with intracavity synchronously pumped optical parametric oscillator

    NASA Astrophysics Data System (ADS)

    Zavadilova, Alena; Kubeček, Václav; Čech, Miroslav; Hiršl, Petr; Jelínkova, Helena; Diels, Jean-Claude

    2006-02-01

    The motivation of this work is the development of laser sensor and gyroscope based on short pulse solid state ring laser. In comparison with regular ring laser containing the gain medium and saturable absorber, where counterpropagating pulses overlap, a ring synchronously pumped optical parametric oscillator, in which the pulse crossing point is controlled externally by the time of arrival of the pump pulses, is the ideal source for short pulse laser sensor. The optimum configuration is a synchronously pumped parametric oscillator inserted inside the optical resonator of the diode pumped mode-locked solid state laser. We are developing a such system, as a first step we have demonstrated operation of a diode pumped Nd:YVO 4 passively mode-locked laser using semiconductor saturable absorber with synchronously pumped intracavity optical parametric oscillator in linear configuration. The repetition rate of the pump laser was 132 MHz and the pulse duration of 15 ps. Parametric oscillator was based on 20 mm long Brewster cut single grating (with poling periode of 30.3 μm) periodically poled magnesium doped lithium niobate (MgO:PPLN) crystal. The temperature tuning of parametric luminescence from the crystal with peak wavelength at 1537 nm - 1550 nm for temperature variation from 30 °C to 57 °C was observed.

  7. Resonant tandem pumping of Tm-doped fiber lasers

    NASA Astrophysics Data System (ADS)

    Creeden, Daniel; Johnson, Benjamin R.; Rines, Glen A.; Setzler, Scott D.

    2014-06-01

    We have demonstrated efficient lasing of a Tm-doped fiber when pumped with another Tm-doped fiber. In these experiments, we use a 1908 nm Tm-doped fiber laser as a pump source for another Tm-doped fiber laser, operating at a slightly longer wavelength (~2000 nm). Pumping in the 1900 nm region allows for very high optical efficiencies, low heat generation, and significant power scaling potential due to the use of fiber laser pumping. The trade-off is that the ground-state pump absorption at 1908 nm is ~37 times lower than at 795nm. However, the absorption cross-section is still sufficiently high enough to achieve effective pump absorption without exceedingly long fiber lengths. This may also be advantageous for distributing the thermal load in higher power applications.

  8. Direct nuclear-pumped lasers using the He-3/n,p/H-3 reaction

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J.; Jalufka, N. W.; Hohl, F.

    1978-01-01

    A description is presented of experimental results concerning a specific class of direct nuclear-pumped lasers classified as 'volumetric nuclear lasers'. In the considered laser system a fissioning gas, He-3, is mixed with the lasing gas to form a homogeneous mixture, resulting in uniform volume excitation. In typical volumetric nuclear lasers a fast-burst reactor is used as a source of neutrons which penetrate a polyethylene moderator. Here the fast neutrons are thermalized. After thermalization, neutrons scatter into the laser cell. Nuclear reactions produce a proton of 0.56 MeV and a tritium ion of 0.19. These ions produce secondary electrons which pump the laser medium creating a population inversion. The results reported demonstrate direct nuclear pumping of He-3-Ar, Xe, Kr, and Cl with the considered system.

  9. Diode pumped thin slab solid-state lasers

    NASA Astrophysics Data System (ADS)

    Cheng, Xiaojin; Wang, Zhiming; Chen, Fan; Xu, Jianqiu

    2008-12-01

    Thermal effect is a serious problem in solid-state lasers. Because of superior thermal property which owed to high aspect ratio of laser crystal, solid-state lasers with thin slab configuration can be scaling to high output power with different laser crystal material and pump structure. In this paper, we present side-pumped passive Q-switched and acousto-optic Q-switched Nd: YAG lasers and end-pumped Tm: YAP lasers. We got a maximum 70W output power of passive Q-switched Nd: YAG laser with 220W pump power, which the pulse duration is around 10ns and the pulse repetition rate is higher than 10kHz. And 73W output power is got while pump power is 200W in acousto-optic Q-switched Nd: YAG lasers. Especially, we also applied the thin slab configuration to end pumped Tm: YAP laser and got a maximum 9.6W output power which the doping concentrations is 4% and cut by c-axis.

  10. XeCl laser pumped iodine laser using t-C4F9I

    NASA Technical Reports Server (NTRS)

    Hwang, In Heon; Han, Kwang S.

    1989-01-01

    An iodine photodissociation laser using t-C4F9I as the active material was pumped by an XeCl laser. An iodine laser output energy of 3 mJ with pulse duration of 25 ns was obtained when the pumping pulse energy was 80 mJ, the iodide pressure was 70 torr, and the reflectance of the output mirror was 85 percent. The high pumping efficiency and low threshold pump power achieved in this experiment are attributable to the high absorption cross section at the pump laser wavelength (308 nm) of the iodide used.

  11. XeCl laser pumped iodine laser using t-C4F9I

    NASA Technical Reports Server (NTRS)

    Hwang, In Heon; Han, Kwang S.; Lee, Ja H.

    1989-01-01

    An iodine photodissociation laser using t-C4F9I as the active material was pumped by a XeCl laser. An iodine laser output energy of 3 mJ with pulse duration of 25 ns was obtained when the pumping pulse energy was 80 mJ, the iodine pressure was 70 torr, and the reflectance of the output mirror was 85 percent. The high pumping efficiency and low threshold pump power achieved in this experiment are attributable to the high absorption cross section at the pump laser wavelength (308 nm) of the iodide used.

  12. High brightness diode-pumped organic solid-state laser

    NASA Astrophysics Data System (ADS)

    Zhao, Zhuang; Mhibik, Oussama; Nafa, Malik; Chénais, Sébastien; Forget, Sébastien

    2015-02-01

    High-power, diffraction-limited organic solid-state laser operation has been achieved in a vertical external cavity surface-emitting organic laser (VECSOL), pumped by a low-cost compact blue laser diode. The diode-pumped VECSOLs were demonstrated with various dyes in a polymer matrix, leading to laser emissions from 540 nm to 660 nm. Optimization of both the pump pulse duration and output coupling leads to a pump slope efficiency of 11% for a DCM based VECSOLs. We report output pulse energy up to 280 nJ with 100 ns long pump pulses, leading to a peak power of 3.5 W in a circularly symmetric, diffraction-limited beam.

  13. High brightness diode-pumped organic solid-state laser

    SciTech Connect

    Zhao, Zhuang; Mhibik, Oussama; Nafa, Malik; Chénais, Sébastien; Forget, Sébastien

    2015-02-02

    High-power, diffraction-limited organic solid-state laser operation has been achieved in a vertical external cavity surface-emitting organic laser (VECSOL), pumped by a low-cost compact blue laser diode. The diode-pumped VECSOLs were demonstrated with various dyes in a polymer matrix, leading to laser emissions from 540 nm to 660 nm. Optimization of both the pump pulse duration and output coupling leads to a pump slope efficiency of 11% for a DCM based VECSOLs. We report output pulse energy up to 280 nJ with 100 ns long pump pulses, leading to a peak power of 3.5 W in a circularly symmetric, diffraction-limited beam.

  14. 20.2W CW 2.118μm Ho:YAlO3 laser pumped by 1.915nm Tm-doped fiber laser

    NASA Astrophysics Data System (ADS)

    Yu, Ting; Bai, Gang; Yang, Zhongguo; Chen, Weibiao

    2015-05-01

    We report on the continuous wave operation of a Ho:YAP laser pumped by an all-fiber Tm-doped fiber laser, the pump laser wavelength is 1.915μm and the output laser wavelength is 2.118μm. The all fiber Tm-doped fiber laser has 70W max output power with 200W pumped power, and the output laser wavelength is 1.915μm. And this laser is used as pump laser to a Ho:YAP laser system. 20.2W CW laser power is obtained from a 0.5 at % Ho3+-doped YAP crystal at 2118.4nm with slope efficiency of 72%.

  15. Compact, passively Q-switched, all-solid-state master oscillator-power amplifier-optical parametric oscillator (MOPA-OPO) system pumped by a fiber-coupled diode laser generating high-brightness, tunable, ultraviolet radiation.

    PubMed

    Peuser, Peter; Platz, Willi; Fix, Andreas; Ehret, Gerhard; Meister, Alexander; Haag, Matthias; Zolichowski, Paul

    2009-07-01

    We report on a compact, tunable ultraviolet laser system that consists of an optical parametric oscillator (OPO) and a longitudinally diode-pumped Nd:YAG master oscillator-power amplifier (MOPA). The pump energy for the whole laser system is supplied via a single delivery fiber. Nanosecond pulses are produced by an oscillator that is passively Q-switched by a Cr(4+):YAG crystal. The OPO is pumped by the second harmonic of the Nd:YAG MOPA. Continuously tunable radiation is generated by an intracavity sum-frequency mixing process within the OPO in the range of 245-260 nm with high beam quality. Maximum pulse energies of 1.2 mJ were achieved, which correspond to an optical efficiency of 3.75%, relating to the pulse energy of the MOPA at 1064 nm. PMID:19571944

  16. DPSS Laser Beam Quality Optimization Through Pump Current Tuning

    SciTech Connect

    Omohundro, Rob; Callen, Alice; Sukuta, Sydney; /San Jose City Coll.

    2012-03-30

    The goal of this study is to demonstrate how a DPSS laser beam's quality parameters can be simultaneously optimized through pump current tuning. Two DPSS lasers of the same make and model were used where the laser diode pump current was first varied to ascertain the lowest RMS noise region. The lowest noise was found to be 0.13% in this region and the best M{sup 2} value of 1.0 and highest laser output power were simultaneously attained at the same current point. The laser manufacturer reported a M{sup 2} value of 1.3 and RMS noise value of .14% for these lasers. This study therefore demonstrates that pump current tuning a DPSS laser can simultaneously optimize RMS Noise, Power and M{sup 2} values. Future studies will strive to broaden the scope of the beam quality parameters impacted by current tuning.

  17. Wave optics simulation of diode pumped alkali laser (DPAL)

    NASA Astrophysics Data System (ADS)

    Endo, Masamori; Nagaoka, Ryuji; Nagaoka, Hiroki; Nagai, Toru; Wani, Fumio

    2016-03-01

    A numerical simulation code for a diode pumped alkali laser (DPAL) was developed. The code employs the Fresnel- Kirchhoff diffraction integral for both laser mode and pump light propagations. A three-dimensional rate equation set was developed to determine the local gain. The spectral divergence of the pump beam was represented by a series of monochromatic beams with different wavelengths. The calculated results showed an excellent agreements with relevant experimental results. It was found that the main channel of the pump power drain is the spontaneous emission from the upper level of the lasing transition.

  18. A hybrid copper/gold laser pumped dye amplifier

    NASA Astrophysics Data System (ADS)

    Ainsworth, M. D.; Piper, J. A.

    1989-01-01

    The design and operating characteristics of a high average power copper vapour laser pumped dye amplifier which is injected with the 627.8 nm output of a gold vapour laser are reported. In these experiments both the CVL pump and GVL injection signals are obtained from a modified CVL plasma tube. Amplifier gain and efficiency as functions of both the pump and injection power, for a number of dyes and dye mixtures, were investigated. Amplifier efficiencies of 25% are reported for CVL pump powers of 4 W and GVL injection powers of only 50 mW.

  19. Method and apparatus for efficient operation of optically pumped laser

    NASA Technical Reports Server (NTRS)

    Sipes, Jr., Donald L. (Inventor)

    1987-01-01

    An optically pumped single mode laser, e.g., Nd:YAG crystal (20) with planoconcave mirrors is increased in efficiency by an order of magnitude to about 8% by optics (25, 27) for focusing the high power multimode output of laser diode arrays (21, 22) into the mode volume (20') of the laser medium (20). A plurality of these optically pumped single mode lasers (1-4) may be cascaded in a ring with dichroic mirrors (M.sub.1 -M.sub.4) at the corners for coupling in the laser diode arrays, each having its own means for spatially tailoring its beam to concentrate pump distribution inside the lasing mode volume of the medium. An InGaAlAs pump diode (30) with its wavelength the same as the lasing medium makes the ring unidirectional.

  20. Tm,Ho:YLF laser end-pumped by a semiconductor diode laser array

    NASA Technical Reports Server (NTRS)

    Hemmati, Hamid (Inventor)

    1990-01-01

    An Ho:YLF crystal including Tm as sensitizers for the activator Ho, is optically pumped with a semiconductor diode laser array to generate 2.1 micron radiation with a pump power to output power of efficiency as high as 68 percent. The prior-art dual sensitizer system of Er and Tm requires cooling, such as by LN2, but by using Tm alone and decreasing the concentrations of Tm and Ho, and decreasing the length of the laser rod to about 1 cm, it has been demonstrated that laser operation can be obtained from a temperature of 77 K with an efficiency as high as 68 percent up to ambient room temperature with an efficiency at that temperature as high as 9 percent.

  1. Ignition experiment design based on γ-pumping gas lasers

    NASA Astrophysics Data System (ADS)

    Bonyushkin, E. K.; Il'kaev, R. I.; Morovov, A. P.; Pavlovskii, A. I.; Lazhintsev, B. V.; Basov, N.; Gus'kov, S. Yu.; Rosanov, V. B.; Zmitrenko, N. V.

    1996-05-01

    Comparative analysis of gas lasers pumped by γ-radiation for ignition experiment is carried out. The possibilities of frequency-time pulse shaping are discussed for these kinds of laser drivers. New type of ICF target (LIGHT-target), which is able to provide an uniform deposition of laser driver energy is proposed as a target for ignition experiment.

  2. Optical nonuniformities in nuclear-pumped cylindrical lasers

    SciTech Connect

    Mat'ev, V Yu; Borovkov, V V; Mel'nikov, S P

    2000-03-31

    The optical nonuniformities, formed as a result of the effect of the inhomogeneous energy deposition by the fission fragments irradiating the laser-active gas from thin uranium-containing layers, were calculated for cylindrical nuclear-pumped gas lasers. The results of the calculations agree with the experiment. (active media. lasers)

  3. Direct solar pumping of semiconductor lasers: A feasibility study

    NASA Technical Reports Server (NTRS)

    Anderson, Neal G.

    1992-01-01

    This report describes results of NASA Grant NAG-1-1148, entitled Direct Solar Pumping of Semiconductor Lasers: A Feasibility Study. The goals of this study were to provide a preliminary assessment of the feasibility of pumping semiconductor lasers in space with directly focused sunlight and to identify semiconductor laser structures expected to operate at the lowest possible focusing intensities. It should be emphasized that the structures under consideration would provide direct optical-to-optical conversion of sunlight into laser light in a single crystal, in contrast to a configuration consisting of a solar cell or storage battery electrically pumping a current injection laser. With external modulation, such lasers could perhaps be efficient sources for intersatellite communications. We proposed specifically to develop a theoretical model of semiconductor quantum-well lasers photopumped by a broadband source, test it against existing experimental data where possible, and apply it to estimating solar pumping requirements and identifying optimum structures for operation at low pump intensities. These tasks have been accomplished, as described in this report of our completed project. The report is organized as follows: Some general considerations relevant to the solar-pumped semiconductor laser problem are discussed in Section 2, and the types of structures chosen for specific investigation are described. The details of the laser model we developed for this work are then outlined in Section 3. In Section 4, results of our study are presented, including designs for optimum lattice-matched and strained-layer solar-pumped quantum-well lasers and threshold pumping estimates for these structures. It was hoped at the outset of this work that structures could be identified which could be expected to operate continuously at solar photoexcitation intensities of several thousand suns, and this indeed turned out to be the case as described in this section. Our project is

  4. TEM00 mode Nd:YAG solar laser by side-pumping a grooved rod

    NASA Astrophysics Data System (ADS)

    Vistas, Cláudia R.; Liang, Dawei; Almeida, Joana; Guillot, Emmanuel

    2016-05-01

    A simple TEM00 mode solar laser system with a grooved Nd:YAG rod pumped through a heliostat-parabolic mirror system is reported here. The radiation coupling capacity of a fused silica tube lens was combined with the multipass pumping ability of a 2 V-shaped cavity to provide efficient side-pumping along a 4.0 mm diameter grooved Nd:YAG single-crystal rod. TEM00 mode solar laser power of 3.4 W was measured by adopting an asymmetric large-mode laser resonant cavity. Record TEM00 mode solar laser collection efficiency of 3.4 W/m2and slope efficiency of 1.9% was achieved, which corresponds to 1.8 and 2.4 times more than the previous TEM00 mode Nd:YAG solar laser using the PROMES-CNRS heliostat-parabolic mirror system, respectively.

  5. Excimer-pumped alkali vapor lasers: a new class of photoassociation lasers

    NASA Astrophysics Data System (ADS)

    Readle, J. D.; Wagner, C. J.; Verdeyen, J. T.; Spinka, T. M.; Carroll, D. L.; Eden, J. G.

    2010-02-01

    Excimer-pumped alkali vapor lasers (XPALs) are a new class of photoassociation lasers which take advantage of the spectrally broad absorption profiles of alkali-rare gas collision pairs. In these systems, transient alkali-rare gas molecules are photopumped from the thermal continuum to a dissociative X2Σ+ 1/2 interaction potential, subsequently populating the n2P3/2 state of the alkali. The absorption profiles >=5 nm and quantum efficiencies >98% have been observed in oscillator experiments, indicating XPAL compatibility with conventional high power laser diode arrays. An alternative technique for populating the n2P3/2 state is direct photoexcitation on the n2P3/2<--n2S1/2 atomic transition. However, because the XPAL scheme employs an off-resonant optical pump, the strengths of resonantly-enhanced nonlinear processes are minimized. Additionally, the absorption coefficient may be adjusted by altering the number densities of the lasing species and/or perturbers, a valuable asset in the design of large volume, high power lasers. We present an overview of XPAL lasers and their operation, including the characteristics of recently demonstrated systems photopumped with a pulsed dye laser. Lasing has been observed in Cs at both 894 nm and 852 nm by pumping CsAr or CsKr pairs as well as in Rb at 795 nm by pumping RbKr. These results highlight the important role of the perturbing species in determining the strength and position of the excimer absorption profile. It is expected that similar results may be obtained in other gas mixtures as similar collision pair characteristics have historically been observed in a wide variety of transient diatomic species.

  6. NIF injection laser system

    NASA Astrophysics Data System (ADS)

    Wisoff, Peter J.; Bowers, Mark W.; Erbert, Gaylen V.; Browning, Donald F.; Jedlovec, Donald R.

    2004-05-01

    The National Ignition Facility (NIF) is a high-power, 192-beam laser facility being built at the Lawrence Livermore National Laboratory. The 192 laser beams that will converge on the target at the output of the NIF laser system originate from a low power fiber laser in the Master Oscillator Room (MOR). The MOR is responsible for generating the single pulse that seeds the entire NIF laser system. This single pulse is phase-modulated to add bandwidth, and then amplified and split into 48 separate beam lines all in single-mode polarizing fiber. Before leaving the MOR, each of the 48 output pulses are temporally sculpted into high contrast shapes using Arbitrary Waveform Generators (AWG). Each output pulse is then carried by optical fiber to the Preamplifier Module (PAM) where it is amplified to the multi-joule level using a diode-pumped regenerative amplifier and a multi-pass, flashlamp-pumped rod amplifier. Inside the PAM, the beam is spatially shaped to pre-compensate for the spatial gain profile in the main laser amplifiers. The output from the PAM is sampled by a diagnostic package called the Input Sensor Package (ISP) and then split into four beams in the Preamplifier Beam Transport System (PABTS). Each of these four beams is injected into one of NIF's 192 beam lines. The combination of the MOR, PAM, ISP and PABTS constitute the Injection Laser System (ILS) for NIF. This system has proven its flexibility of providing a wide variety of pulse shapes and energies during the first experiments utilizing four beam lines of NIF.

  7. 14 J/2 Hz Yb3+:YAG diode pumped solid state laser chain.

    PubMed

    Gonçalvès-Novo, Thierry; Albach, Daniel; Vincent, Bernard; Arzakantsyan, Mikayel; Chanteloup, Jean-Christophe

    2013-01-14

    The Lucia laser chain is a Diode Pumped Solid State Laser system based on Yb3+ doped YAG disks used in an active mirror scheme. Front-end and amplifier stages are presented with recent energetic performances (14 J/2 Hz) achieved with improved pumping and extraction architectures. Emphasis is given on the crucial role of ASE and thermal mitigation considerations in engineering the amplifier head. PMID:23388979

  8. Multiple pass effects in high efficiency laser pumping cavities.

    PubMed

    Evtuhov, V; Neeland, J K

    1967-03-01

    Some effects connected with multiple passes of pump radiation in laser pump cavities are discussed. These effects include changes in mercury arc lamp operating characteristics, when the lamps are used inside the cavities as pump sources, and unexpectedly low pulse (but not cw) thresholds in double elliptical cavities. It is shown analytically that these effects can, at least in part, be attributed to the shapes of the pump light energy distribution curves after multiple passes through the pump cavities, and to the relative opacities of flash and continuous lamps. PMID:20057775

  9. Nuclear-pumped laser operating in the master oscillator-amplifier regime

    SciTech Connect

    Pikulev, A A; Tsvetkov, V M; Sosnin, P V; Sinyanskii, A A

    2008-07-31

    The efficiency of a master oscillator-amplifier scheme and the possibility of its using in multichannel nuclear-pumped laser systems are studied. The small-signal gain and saturation parameter are measured for the He:Ar:Xe = 380:380:1 mixture at a pressure of 1 atm at a wavelength of 2.03 {mu}m. It is shown that the small-signal gain increases linearly with the specific pump power density and achieves 1.1-1.2 m{sup -1} at a pump density of 40 W cm{sup -3}. The saturation parameter is almost independent of the pump power and is equal to 70-90 W cm{sup -2}. It is found that at the pump-pulse maximum (40 W cm{sup -3}) the laser radiation power increases after amplification by 100%. (active media, lasers, and amplifiers)

  10. Nuclear-pumped lasers for large-scale applications

    SciTech Connect

    Anderson, R.E.; Leonard, E.M.; Shea, R.F.; Berggren, R.R.

    1989-05-01

    Efficient initiation of large-volume chemical lasers may be achieved by neutron induced reactions which produce charged particles in the final state. When a burst mode nuclear reactor is used as the neutron source, both a sufficiently intense neutron flux and a sufficiently short initiation pulse may be possible. Proof-of-principle experiments are planned to demonstrate lasing in a direct nuclear-pumped large-volume system; to study the effects of various neutron absorbing materials on laser performance; to study the effects of long initiation pulse lengths; to demonstrate the performance of large-scale optics and the beam quality that may be obtained; and to assess the performance of alternative designs of burst systems that increase the neutron output and burst repetition rate. 21 refs., 8 figs., 5 tabs.

  11. Passive apparatus for stabilizing a flashlamp-pumped dye laser

    SciTech Connect

    De Wilde, M.A.; Decker, L.J.

    1986-04-29

    A flash lamp pumped, dye laser apparatus is described which consists of a flash lamp and a liquid dye solution in a transparent compartment proximate to the flash lamp. The compartment is also connected to a tubular circulatory system for moving the liquid dye. The dye solution is activated by flashing of the lamp for lasing to emit light, the lamp and compartment enclosed in a cooling first water jacket, the jacket enclosing deionized water for cooling, an improved cooling system wherein the temperature of the deionized water and the liquid dye solution are maintained within 0.5/sup 0/C of one another, enabling the laser for pulsing at a stabilized 10 pulses per second rate.

  12. Optimising the efficiency of pulsed diode pumped Yb:YAG laser amplifiers for ns pulse generation.

    PubMed

    Ertel, K; Banerjee, S; Mason, P D; Phillips, P J; Siebold, M; Hernandez-Gomez, C; Collier, J C

    2011-12-19

    We present a numerical model of a pulsed, diode-pumped Yb:YAG laser amplifier for the generation of high energy ns-pulses. This model is used to explore how optical-to-optical efficiency depends on factors such as pump duration, pump spectrum, pump intensity, doping concentration, and operating temperature. We put special emphasis on finding ways to achieve high efficiency within the practical limitations imposed by real-world laser systems, such as limited pump brightness and limited damage fluence. We show that a particularly advantageous way of improving efficiency within those constraints is operation at cryogenic temperature. Based on the numerical findings we present a concept for a scalable amplifier based on an end-pumped, cryogenic, gas-cooled multi-slab architecture. PMID:22274245

  13. One- and two-photon pumped soft lithographed DFB laser systems based on semiconductor core-shell quantum dots

    NASA Astrophysics Data System (ADS)

    Todescato, F.; Fortunati, I.; Gardin, S.; Signorini, R.; Bozio, R.; Jasieniak, J. J.; Martucci, A.; Della Giustina, G.; Brusatin, G.; Guglielmi, M.

    2010-02-01

    In the last years inorganic semiconductor (particularly CdSe and CdS) quantum dots (QDs) have received great attention for their important optical properties. The possibility to tune the emission wavelength, together with their high fluorescence quantum efficiency and photostability, can be exploited in photonic and optoelectronic technological applications. The design of DFB devices, based on QDs as active optical material, leads to the realization of compact laser systems. In this work we explore the use of an inorganic/organic hybrid material composed of CdSe-ZnS semiconductor quantum dots doped into a zirconia sol-gel matrix for optical gain applications. Through the use of soft lithography on a sol-gel germania-silica hybrid, large scale distributed feedback gratings can be created. Used in conjunction with the CdSe-ZnS/ZrO2 hybrids, these gratings can act as microcavities and allow for the realization of true lasing action. The lasing properties within these devices are characterized in the femtosecond regime by both one- and two-photon excitation. From experimental data the value of the optical gain of the core-shell quantum dot samples has been estimated. Moreover, one- and two-photon lasing threshold and stability are reported.

  14. A 1 kHz A-scan rate pump-probe laser-ultrasound system for robust inspection of composites.

    PubMed

    Pelivanov, Ivan; Shtokolov, Alex; Wei, Chen-Wei; O'Donnell, Matthew

    2015-09-01

    We recently built a fiber-optic laser-ultrasound (LU) scanner for nondestructive evaluation (NDE) of aircraft composites and demonstrated its greatly improved sensitivity and stability compared with current noncontact systems. It is also very attractive in terms of cost, stability to environmental noise and surface roughness, simplicity in adjustment, footprint, and flexibility. A new type of a balanced fiber-optic Sagnac interferometer is a key component of this all-optical LU pump-probe system. Very high A-scan rates can be achieved because no reference arm or stabilization feedback are needed. Here, we demonstrate LU system performance at 1000 A-scans/s combined with a fast 2-D translator operating at a scanning speed of 100 mm/s with a peak acceleration of 10 m/s(2) in both lateral directions to produce parallel B-scans at high rates. The fast scanning strategy is described in detail. The sensitivity of this system, in terms of noise equivalent pressure, was further improved to be only 8.3 dB above the Nyquist thermal noise limit. To our knowledge, this is the best reported sensitivity for a noncontact ultrasonic detector of this dimension used to inspect aircraft composites. PMID:26415130

  15. Theoretical studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, W. L.

    1983-01-01

    Possible types of lasers were surveyed for solar power conversion. The types considered were (1) liquid dye lasers, (2) vapor dye lasers, and (3) nondissociative molecular lasers. These are discussed.

  16. Heat generation and thermo-mechanical effect modeling in longitudinally diode-pumped solid state lasers

    NASA Astrophysics Data System (ADS)

    Lakhdari, Fouad; Osmani, Ismahen; Tabet, Saida

    2015-09-01

    Thermal management in solid state laser is a challenge to the high power laser industry's ability to provide continued improvements in device and system performance. In this work an investigation of heat generation and thermo-mechanical effect in a high-power Nd:YAG and Yb:YAG cylindrical-type solid state laser pumped longitudinally with different power by fibre coupled laser diode is carried out by numerical simulation based on the finite element method (FEM). Impact of the dopant concentration on the power conversion efficiency is included in the simulation. The distribution of the temperature inside the lasing material is resolute according to the thermal conductivity. The thermo-mechanical effect is explored as a function of pump power in order to determine the maximum pumping power allowed to prevent the crystal's fracture. The presented simulations are in broad agreement with analytical solutions; provided that the boundary condition of the pump induced heat generation is accurately modelled.

  17. 100  J-level nanosecond pulsed diode pumped solid state laser.

    PubMed

    Banerjee, Saumyabrata; Mason, Paul D; Ertel, Klaus; Jonathan Phillips, P; De Vido, Mariastefania; Chekhlov, Oleg; Divoky, Martin; Pilar, Jan; Smith, Jodie; Butcher, Thomas; Lintern, Andrew; Tomlinson, Steph; Shaikh, Waseem; Hooker, Chris; Lucianetti, Antonio; Hernandez-Gomez, Cristina; Mocek, Tomas; Edwards, Chris; Collier, John L

    2016-05-01

    We report on the successful demonstration of a 100 J-level, diode pumped solid state laser based on cryogenic gas cooled, multi-slab ceramic Yb:YAG amplifier technology. When operated at 175 K, the system delivered a pulse energy of 107 J at a 1 Hz repetition rate and 10 ns pulse duration, pumped by 506 J of diode energy at 940 nm, corresponding to an optical-to-optical efficiency of 21%. To the best of our knowledge, this represents the highest energy obtained from a nanosecond pulsed diode pumped solid state laser. This demonstration confirms the energy scalability of the diode pumped optical laser for experiments laser architecture. PMID:27128081

  18. Reversing the pump dependence of a laser at an exceptional point

    PubMed Central

    Brandstetter, M.; Liertzer, M.; Deutsch, C.; Klang, P.; Schöberl, J.; Türeci, H. E.; Strasser, G.; Unterrainer, K.; Rotter, S.

    2014-01-01

    When two resonant modes in a system with gain or loss coalesce in both their resonance position and their width, a so-called exceptional point occurs, which acts as a source of non-trivial physics in a diverse range of systems. Lasers provide a natural setting to study such non-Hermitian degeneracies, as they feature resonant modes and a gain material as their basic constituents. Here we show that exceptional points can be conveniently induced in a photonic molecule laser by a suitable variation of the applied pump. Using a pair of coupled microdisk quantum cascade lasers, we demonstrate that in the vicinity of these exceptional points the coupled laser shows a characteristic reversal of its pump dependence, including a strongly decreasing intensity of the emitted laser light for increasing pump power. PMID:24925314

  19. Further remarks on electron beam pumping of laser materials.

    PubMed

    Klein, C A

    1966-12-01

    This article demonstrates that recently completed studies on the energy dissipation of kilovolt electron beams in solids provide readily applicable methods for assessing the situation in electron beam pumped lasers. PMID:20057662

  20. Analysis of the pump-beam path in corner-pumped slab laser

    SciTech Connect

    Chen Li; Qiang Liu; Mali Gong; Gang Chen; Ping Yan

    2007-06-30

    The propagation of the pump radiation in active slab elements is considered. Conditions of the total internal reflection of the pump radiation are obtained, and are used to construct a series of graphical illustrations of reflection characteristics of different active elements. (control of laser radiation parameters)

  1. High-power synchronously pumped femtosecond Raman fiber laser.

    PubMed

    Churin, D; Olson, J; Norwood, R A; Peyghambarian, N; Kieu, K

    2015-06-01

    We report a high-power synchronously pumped femtosecond Raman fiber laser operating in the normal dispersion regime. The Raman laser is pumped by a picosecond Yb(3+)-doped fiber laser. It produces highly chirped pulses with energy up to 18 nJ, average power of 0.76 W and 88% efficiency. The pulse duration is measured to be 147 fs after external compression. We observed two different regimes of operation of the laser: coherent and noise-like regime. Both regimes were experimentally characterized. Numerical simulations are in a good agreement with experimental results. PMID:26030549

  2. The LASL program in nuclear pumped liquid lasers

    NASA Technical Reports Server (NTRS)

    Mansfield, C. R.; Bird, P. F.; Davis, J. F.

    1979-01-01

    The development of nuclear-pumped, liquid-based lanthanide ion lasers is discussed. Early investigations of lanthanide ion lasers have lead to solid-state and gaseous neodymium lasers, and a demonstration of lasing in the liquid state. Solvents containing organic chelating agents have been employed in liquid Eu(+3) and Tb(+3) lasers to extend fluorescence lifetimes, however aprotic solvents have been found to enable the development of large-scale liquid lasers. The advantages to be gained from high-power nuclear-pumped lasers based on lanthanide solutions include the high density of fissile materials possible, and a nuclear pumping cell which can operate in either a nuclear or optical pumping mode is being fabricated at the Los Alamos Scientific Laboratory to investigate the nuclear pumping of liquid lanthanide ion lasers. Areas that need exploration before specific laser design features can be considered include energy channeling within the liquid upon excitation, radiation damage due to solvent dissociation, and reactor technology for the development of a self-critical liquid reactor.

  3. Nuclear pumping of a neutral carbon laser

    NASA Technical Reports Server (NTRS)

    Prelas, M. A.; Anderson, J. H.; Boody, F. P.; Nagalingam, S. J. S.; Miley, G. H.

    1978-01-01

    Nuclear pumped lasing on the neutral carbon line at 1.45 microns has been achieved in mixtures of He-CO, He-N2-CO, He-CO2, and Ne-CO and Ne-CO2. A minimum thermal neutron flux of 2 x 10 to the 14th n/sq cm-sec was sufficient for oscillation in the helium mixtures. The peak of the laser output was delayed up to 5.5 ms relative to the neutron pulse in He-CO2, He-N2-CO, Ne-CO and Ne-CO2 mixtures while no delay was observed in He-CO mixtures. Lasing was obtained with helium pressures from 20 to 800 T, Ne pressures from 100 to 200 T, CO from 0.25 to 20 mT, N2 from 0.5 to 5 mT, and CO2 from 0.1 to 25 mT in the respective mixtures.

  4. Nuclear pumping of a neutral carbon laser

    NASA Technical Reports Server (NTRS)

    Prelas, M. A.; Anderson, J. H.; Boody, F. P.; Nagalingam, S. J. S.; Miley, G. H.

    1978-01-01

    Nuclear pumped lasing on the neutral carbon line at 1.45 micron was achieved in mixtures of He-CO, He-N2-CO, He-CO2, and Ne-CO and Ne-CO2. A minimum thermal neutron flux of 2 x 10 to the 14th power sq cm-sec was sufficient for oscillation in the helium mixtures. The peak of the laser output was delayed up to 5.5 ms relative to the neutron pulse in He-CO2, He-N2-CO, Ne-CO, and Ne-CO2 mixtures while no delay was observed in He-CO mixtures. Lasing was obtained with helium pressures from 20 to 800 T, Ne pressures from 100 to 200 T, CO from 0.25 to 20 mT, N2 from 0.5 mT, and CO2 from 0.1 to 25 mT in the respective mixtures.

  5. Laser and solar-photovoltaic space power systems comparison. II.

    NASA Technical Reports Server (NTRS)

    De Young, R. J.; Stripling, J.; Enderson, T. M.; Humes, D. H.; Davis, W. T.

    1984-01-01

    A comparison of total system cost is made between solar photovoltaic and laser/receiver systems. The laser systems assume either a solar-pumped CO2 blackbody transfer laser with MHD receiver or a solar pumped liquid neodymium laser with a photovoltaic receiver. Total system costs are less for the laser systems below 300 km where drag is significant. System costs are highly dependent on altitude.

  6. Nuclear pumped lasers: Advantages of O2 (1 delta)

    NASA Technical Reports Server (NTRS)

    Taylor, J. J.

    1979-01-01

    Nuclear pumped laser technology was evaluated as a possible future weapons contender. It was determined that in order to become a primary weapon the following engineering problems must be solved: shielding, heat dissipation, high efficiency fixed focus pumping, good beam quality, and thermal blooming.

  7. Tunable, diode side-pumped Er: YAG laser

    DOEpatents

    Hamilton, Charles E.; Furu, Laurence H.

    1997-01-01

    A discrete-element Er:YAG laser, side pumped by a 220 Watt peak-power InGaAs diode array, generates >500 mWatts at 2.94 .mu.m, and is tunable over a 6 nm range near about 2.936 .mu.m. The oscillator is a plano-concave resonator consisting of a concave high reflector, a flat output coupler, a Er:YAG crystal and a YAG intracavity etalon, which serves as the tuning element. The cavity length is variable from 3 cm to 4 cm. The oscillator uses total internal reflection in the Er:YAG crystal to allow efficient coupling of the diode emission into the resonating modes of the oscillator. With the tuning element removed, the oscillator produces up to 1.3 Watts of average power at 2.94 .mu.m. The duty factor of the laser is 6.5% and the repetition rate is variable up to 1 kHz. This laser is useful for tuning to an atmospheric transmission window at 2.935 .mu.m (air wavelength). The laser is also useful as a spectroscopic tool because it can access several infrared water vapor transitions, as well as transitions in organic compounds. Other uses include medical applications (e.g., for tissue ablation and uses with fiber optic laser scalpels) and as part of industrial effluent monitoring systems.

  8. Tunable, diode side-pumped Er:YAG laser

    DOEpatents

    Hamilton, C.E.; Furu, L.H.

    1997-04-22

    A discrete-element Er:YAG laser, side pumped by a 220 Watt peak-power InGaAs diode array, generates >500 mWatts at 2.94 {micro}m, and is tunable over a 6 nm range near about 2.936 {micro}m. The oscillator is a plano-concave resonator consisting of a concave high reflector, a flat output coupler, a Er:YAG crystal and a YAG intracavity etalon, which serves as the tuning element. The cavity length is variable from 3 cm to 4 cm. The oscillator uses total internal reflection in the Er:YAG crystal to allow efficient coupling of the diode emission into the resonating modes of the oscillator. With the tuning element removed, the oscillator produces up to 1.3 Watts of average power at 2.94 {micro}m. The duty factor of the laser is 6.5% and the repetition rate is variable up to 1 kHz. This laser is useful for tuning to an atmospheric transmission window at 2.935 {micro}m (air wavelength). The laser is also useful as a spectroscopic tool because it can access several infrared water vapor transitions, as well as transitions in organic compounds. Other uses include medical applications (e.g., for tissue ablation and uses with fiber optic laser scalpels) and as part of industrial effluent monitoring systems. 4 figs.

  9. Large area electron beam pumped krypton fluoride laser amplifier

    SciTech Connect

    Sethian, J.D.; Obenschain, S.P.; Gerber, K.A.; Pawley, C.J.; Serlin, V.; Sullivan, C.A.; Webster, W.; Deniz, A.V.; Lehecka, T.; McGeoch, M.W.; Altes, R.A.; Corcoran, P.A.; Smith, I.D.; Barr, O.C.

    1997-06-01

    Nike is a recently completed multi-kilojoule krypton fluoride (KrF) laser that has been built to study the physics of direct drive inertial confinement fusion. This paper describes in detail both the pulsed power and optical performance of the largest amplifier in the Nike laser, the 60 cm amplifier. This is a double pass, double sided, electron beam-pumped system that amplifies the laser beam from an input of 50 J to an output of up to 5 kJ. It has an optical aperture of 60 cm {times} 60 cm and a gain length of 200 cm. The two electron beams are 60 cm high {times} 200 cm wide, have a voltage of 640 kV, a current of 540 kA, and a flat top power pulse duration of 250 ns. A 2 kG magnetic field is used to guide the beams and prevent self-pinching. Each electron beam is produced by its own Marx/pulse forming line system. The amplifier has been fully integrated into the Nike system and is used on a daily basis for laser-target experiments. {copyright} {ital 1997 American Institute of Physics.}

  10. Entanglement formulation in the framework of electrically pumped laser cavity

    NASA Astrophysics Data System (ADS)

    Getahun, Solomon

    2016-02-01

    We analyze electrically pumped atomic cavity coupled to a two-mode vacuum reservoirs via a single-port mirror whose open cavity contains N nondegenerate three-level cascade atoms. We carry out our analysis by putting the noise operators associated with a vacuum reservoir in normal order. It is found that unlike the mean photon number, the quadrature squeezing and the degree of entanglement do not depend on the number of atoms. This implies that the quadrature squeezing and the degree of entanglement of the cavity light do not depend on the number of photons. We have also shown that the light generated by the three-level laser is in a squeezed and entangled state, with maximum quadrature squeezing and degree of entanglement being 50%. Moreover, the mean photon number of the system in which the laser operating at threshold and above threshold does not depend on the spontaneous decay constant.

  11. Airborne-mercury detection by resonant UV laser pumping.

    PubMed

    Bahns, J T; Lynds, L; Stwalley, W C; Simmons, V; Robinson, T; Bililign, S

    1997-05-15

    Optical pumping of the Hg(0) (6s (1)S(0) --> 6p (3)P(1)) transition at 253.7 nm (in air) leads to extremely fast energy transfer and strong laser-induced-fluorescence (LIF) from the Hg(0) (7s(3)S(1) --> 6p (3)P(2)) green transition at 546.2 nm, which is not directly populated by the laser. Ionization occurs simultaneously and becomes particularly strong at reduced background pressures. These observations are consistent with the existence of a multiphoton process followed by electron collisional excitation. Preliminary studies are made to evaluate these phenomena for detecting elemental airborne mercury by LIF and point monitoring with an ionization detector. Measured sensitivities of 2 and 10 parts in 10(9) (ppb), respectively, at 0.1-Torr air pressure are projected to increase to 1 x 10(-4) and 1 x 10(-5) ppb after relevant system optimization. PMID:18185642

  12. Feasibility of supersonic diode pumped alkali lasers: Model calculations

    SciTech Connect

    Barmashenko, B. D.; Rosenwaks, S.

    2013-04-08

    The feasibility of supersonic operation of diode pumped alkali lasers (DPALs) is studied for Cs and K atoms applying model calculations, based on a semi-analytical model previously used for studying static and subsonic flow DPALs. The operation of supersonic lasers is compared with that measured and modeled in subsonic lasers. The maximum power of supersonic Cs and K lasers is found to be higher than that of subsonic lasers with the same resonator and alkali density at the laser inlet by 25% and 70%, respectively. These results indicate that for scaling-up the power of DPALs, supersonic expansion should be considered.

  13. Development of a flashlamp-pumped Cr:LiSAF laser operating at 30 Hz

    NASA Astrophysics Data System (ADS)

    Elgul Samad, Ricardo; Calvo Nogueira, Gesse Eduardo; Licia Baldochi, Sonia; Dias Vieira, Nilson, Jr.

    2006-05-01

    Cr3+:LiSrAlF6 crystals are an interesting laser medium because of their spectroscopic characteristics: They present a broad emission band in the near infrared and can be pumped either by a flashlamp or by diodes. Up to now, their limitation has been mostly due to their poor thermal properties that limit the laser performance either in the repetition rate in a pulsed system or output power in cw systems. We have designed and constructed a flashlamp-pumped laser using a standard rod pumping cavity that avoids most of the heat generated in the pumping process and allows operation at a fairly high repetition rate of 30 Hz with a high average power of 20 W in a conservative operation mode.

  14. Diode-pumped Alexandrite ring laser for lidar applications

    NASA Astrophysics Data System (ADS)

    Munk, A.; Jungbluth, B.; Strotkamp, M.; Hoffmann, H.-D.; Poprawe, R.; Höffner, J.

    2016-03-01

    We present design and performance data of a diode-pumped Q-switched Alexandrite ring laser in the millijoule regime, which is longitudinally pumped by laser diode bar modules in the red spectral range. As a first step, a linear resonator was designed and characterized in qcw operation as well as in Q-switched operation. Based on these investigations, two separate linear cavities were set up, each with one Alexandrite crystal longitudinally pumped by one diode module. The two cavities are fused together and form a ring cavity which yields up to 6 mJ pulse burst energy in the qcw regime at 770 nm.

  15. Analysis of electric-submersible-pumping systems

    SciTech Connect

    Nolen, K.B.; Gibbs, S.G.

    1989-05-01

    This paper presents a field-proven analytical method of evaluating electric-submersible-pumping equipment and well performance jointly. A computerized mathematical model that considers the effects of free gas, pump speed (variable-frequency drives), and pump tapering is described. The method allows accurate calculations of important downhole parameters, including pump intake pressure, pump intake volume (including free gas), pump pressure, and fluid density profile. Lifting cost parameters - such as pump and motor power requirements, monthly power consumption, pump and motor performance, and overall system efficiency - are also determined. Once operating conditions are known, decisions can be made on ways to increase production (if additional potential exists) or to reduce operating costs. Thus, the same basic goals that often justify frequent analysis of rod pumping systems can be applied to submersible pumping.

  16. Heat pump system

    DOEpatents

    Swenson, Paul F.; Moore, Paul B.

    1977-01-01

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  17. Heat pump system

    DOEpatents

    Swenson, Paul F.; Moore, Paul B.

    1983-01-01

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  18. Heat pump system

    DOEpatents

    Swenson, Paul F.; Moore, Paul B.

    1983-06-21

    An air heating and cooling system for a building includes an expansion type refrigeration circuit and a vapor power circuit. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The vapor power circuit includes two heat exchangers, one of which is disposed in series air flow relationship with the indoor refrigeration circuit heat exchanger and the other of which is disposed in series air flow relationship with the outdoor refrigeration circuit heat exchanger. Fans powered by electricity generated by a vapor power circuit alternator circulate indoor air through the two indoor heat exchangers and circulate outside air through the two outdoor heat exchangers. The system is assembled as a single roof top unit, with a vapor power generator and turbine and compressor thermally insulated from the heat exchangers, and with the indoor heat exchangers thermally insulated from the outdoor heat exchangers.

  19. Negative feedback system reduces pump oscillations

    NASA Technical Reports Server (NTRS)

    Rosenmann, W.

    1967-01-01

    External negative feedback system counteracts low frequency oscillations in rocket engine propellant pumps. The system uses a control piston to sense pump discharge fluid on one side and a gas pocket on the other.

  20. Four-Pass Coupler for Laser-Diode-Pumped Solid-State Laser

    NASA Technical Reports Server (NTRS)

    Coyle, Donald B.

    2008-01-01

    A four-pass optical coupler affords increased (in comparison with related prior two-pass optical couplers) utilization of light generated by a laser diode in side pumping of a solid-state laser slab. The original application for which this coupler was conceived involves a neodymium-doped yttrium aluminum garnet (Nd:YAG) crystal slab, which, when pumped by a row of laser diodes at a wavelength of 809 nm, lases at a wavelength of 1,064 nm. Heretofore, typically, a thin laser slab has been pumped in two passes, the second pass occurring by virtue of reflection of pump light from a highly reflective thin film on the side opposite the side through which the pump light enters. In two-pass pumping, a Nd:YAG slab having a thickness of 2 mm (which is typical) absorbs about 84 percent of the 809-nm pump light power, leaving about 16 percent of the pump light power to travel back toward the laser diodes. This unused power can cause localized heating of the laser diodes, thereby reducing their lifetimes. Moreover, if the slab is thinner than 2 mm, then even more unused power travels back toward the laser diodes. The four-pass optical coupler captures most of this unused pump light and sends it back to the laser slab for two more passes. As a result, the slab absorbs more pump light, as though it were twice as thick. The gain and laser cavity beam quality of a smaller laser slab in conjunction with this optical coupler can thus be made comparable to those of a larger two-pass-pumped laser slab.

  1. Heat pump system

    DOEpatents

    Swenson, Paul F.; Moore, Paul B.

    1979-01-01

    An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchangers and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

  2. Heat pump system

    DOEpatents

    Swenson, Paul F.; Moore, Paul B.

    1982-01-01

    An air heating and cooling system for a building includes an expansion-type refrigeration circuit and a heat engine. The refrigeration circuit includes two heat exchangers, one of which is communicated with a source of indoor air from the building and the other of which is communicated with a source of air from outside the building. The heat engine includes a heat rejection circuit having a source of rejected heat and a primary heat exchanger connected to the source of rejected heat. The heat rejection circuit also includes an evaporator in heat exchange relation with the primary heat exchanger, a heat engine indoor heat exchanger, and a heat engine outdoor heat exchanger. The indoor heat exchangers are disposed in series air flow relationship, with the heat engine indoor heat exchanger being disposed downstream from the refrigeration circuit indoor heat exchanger. The outdoor heat exchangers are also disposed in series air flow relationship, with the heat engine outdoor heat exchanger disposed downstream from the refrigeration circuit outdoor heat exchanger. A common fluid is used in both of the indoor heat exchanges and in both of the outdoor heat exchangers. In a first embodiment, the heat engine is a Rankine cycle engine. In a second embodiment, the heat engine is a non-Rankine cycle engine.

  3. Heterodyne laser spectroscopy system

    DOEpatents

    Wyeth, Richard W.; Paisner, Jeffrey A.; Story, Thomas

    1990-01-01

    A heterodyne laser spectroscopy system utilizes laser heterodyne techniques for purposes of laser isotope separation spectroscopy, vapor diagnostics, processing of precise laser frequency offsets from a reference frequency, and provides spectral analysis of a laser beam.

  4. Heterodyne laser spectroscopy system

    DOEpatents

    Wyeth, Richard W.; Paisner, Jeffrey A.; Story, Thomas

    1989-01-01

    A heterodyne laser spectroscopy system utilizes laser heterodyne techniques for purposes of laser isotope separation spectroscopy, vapor diagnostics, processing of precise laser frequency offsets from a reference frequency and the like, and provides spectral analysis of a laser beam.

  5. Electric-discharge-pumped nitrogen ion laser

    NASA Technical Reports Server (NTRS)

    Laudenslager, J. B.; Pacala, T. J.; Wittig, C.

    1976-01-01

    The routine operation is described of an N2(+) laser oscillating on the first negative band system of N2(+) which is produced in a preionized transverse discharge device. The discharge design incorporates features which favor the efficient production of the excitation transfer reaction of He2(+) with N2. A capacitive discharge switched by means of a high-current grounded grid thyratron is used to meet the design requirement of a volumetric discharge in high-pressure gas mixtures where the electric discharge need not have an ultrafast rise time (greater than 10 nsec) but should be capable of transferring large quantities of stored electric energy to the gas. A peak power of 180 kW in an 8-nsec laser pulse was obtained with a 0.1% mixture of N2 in helium at a total pressure of 3 atm. The most intense laser oscillations were observed on the (0,1) vibrational transition at 427.8 microns.

  6. Diode-pumped dysprosium laser materials

    NASA Astrophysics Data System (ADS)

    Bowman, S. R.; Condon, N. J.; O'Connor, S.; Rosenberg, A.

    2009-05-01

    We are investigating materials for direct blue solid-state lasers assuming UV excitation with GaN based laser diodes. Room temperature spectroscopy is reported relevant to a proposed quasi-three level laser from the 4F9/2 level in trivalent dysprosium. Modeling based on these measurements suggests this is a promising new laser transition.

  7. Diode-pumped solid state laser for inertial fusion energy

    SciTech Connect

    Payne, S.A.; Krupke, W.F.; Orth, C.D.

    1994-11-01

    The authors evaluate the prospect for development of a diode-pumped solid-state-laser driver in an inertial fusion energy power plant. Using a computer code, they predict that their 1 GWe design will offer electricity at 8.6 cents/kW {center_dot} hr with the laser operating at 8.6% efficiency and the recycled power level at 31%. The results of their initial subscale experimental testbed of a diode-pumped solid state laser are encouraging, demonstrating good efficiencies and robustness.

  8. Design and Construction of Simple, Nitrogen-Laser-Pumped, Tunable Dye Lasers

    ERIC Educational Resources Information Center

    Hilborn, Robert C.

    1978-01-01

    The basic physical principles of dye lasers are discussed and used to analyze the design and operation of tunable dye lasers pumped by pulsed nitrogen lasers. Details of the design and construction of these dye lasers are presented. Some simple demonstration experiments are described. (BB)

  9. Diode-laser-pump module with integrated signal ports for pumping amplifying fibers and method

    DOEpatents

    Savage-Leuchs; Matthias P.

    2009-05-26

    Apparatus and method for collimating pump light of a first wavelength from laser diode(s) into a collimated beam within an enclosure having first and second optical ports, directing pump light from the collimated beam to the first port; and directing signal light inside the enclosure between the first and second port. The signal and pump wavelengths are different. The enclosure provides a pump block having a first port that emits pump light to a gain fiber outside the enclosure and that also passes signal light either into or out of the enclosure, and another port that passes signal light either out of or into the enclosure. Some embodiments use a dichroic mirror to direct pump light to the first port and direct signal light between the first and second ports. Some embodiments include a wavelength-conversion device to change the wavelength of at least some of the signal light.

  10. Improving Reliability of High Power Quasi-CW Laser Diode Arrays for Pumping Solid State Lasers

    NASA Technical Reports Server (NTRS)

    Amzajerdian, Farzin; Meadows, Byron L.; Baker, Nathaniel R.; Barnes, Bruce W.; Baggott, Renee S.; Lockard, George E.; Singh, Upendra N.; Kavaya, Michael J.

    2005-01-01

    Most Lidar applications rely on moderate to high power solid state lasers to generate the required transmitted pulses. However, the reliability of solid state lasers, which can operate autonomously over long periods, is constrained by their laser diode pump arrays. Thermal cycling of the active regions is considered the primary reason for rapid degradation of the quasi-CW high power laser diode arrays, and the excessive temperature rise is the leading suspect in premature failure. The thermal issues of laser diode arrays are even more drastic for 2-micron solid state lasers which require considerably longer pump pulses compared to the more commonly used pump arrays for 1-micron lasers. This paper describes several advanced packaging techniques being employed for more efficient heat removal from the active regions of the laser diode bars. Experimental results for several high power laser diode array devices will be reported and their performance when operated at long pulsewidths of about 1msec will be described.

  11. Cs laser with unstable cavity transversely pumped by multiple diode lasers.

    PubMed

    Zhdanov, B V; Shaffer, M K; Knize, R J

    2009-08-17

    We have demonstrated a Cs vapor laser with an unstable resonator transversely pumped by 15 narrowband laser diode arrays. A slope efficiency of 43%, a total optical efficiency of 31% and a maximum output power 49 W were obtained with a pump power of 157 Watts. PMID:19687954

  12. Fiber laser pumped burst-mode operated picosecond mid-infrared laser

    NASA Astrophysics Data System (ADS)

    Wei, Kai-Hua; Jiang, Pei-Pei; Wu, Bo; Chen, Tao; Shen, Yong-Hang

    2015-02-01

    We demonstrate a compact periodically poled MgO-doped lithium niobate (MgO:PPLN)-based optical parametric oscillator (OPO) quasi-synchronously pumped by a fiber laser system with burst-mode operation. The pump source is a peak-power-selectable pulse-multiplied picosecond Yb fiber laser. The chirped pulses from a figure of eight-cavity mode-locked fiber laser seed are narrowed to a duration of less than 50 ps using an FBG reflector and a circulator. The narrowed pulses are directed to pass through a pulse multiplier and to form pulse bunches, each of which is composed of 13 sub-pulses. The obtained pulse bunches are amplified by two-stage fiber pre-amplifiers: one-stage is core-pumped and the other is cladding-pumped. A fiberized acousto-optic modulator is inserted to control the pulse repetition rate (PRR) of the pulse bunches before they are power-amplified in the final amplifier stage with a large mode area (LMA) PM Yb-doped fiber. The maximum average powers from the final amplifier are 85 W, 60 W, and 45 W, respectively, corresponding to the PRR of 2.72 MHz, 1.36 MHz, and 0.68 MHz. The amplified pulses are directed to pump an MgO:PPLN-based optical parametric oscillator (OPO). A maximum peak power at 3.45 μm is obtained approximately to be 8.4 kW. Detailed performance characteristics are presented. Project supported by the National Natural Science Foundation of China (Grant No. 61078015) and the National Basic Research Program of China (Grant No. 2011CB311803).

  13. Optically pumped tunable HBr laser in the mid-infrared region.

    PubMed

    Koen, Wayne; Jacobs, Cobus; Bollig, Christoph; Strauss, Hencharl J; Esser, M J Daniel; Botha, Lourens R

    2014-06-15

    An optically pumped tunable HBr laser has been demonstrated for the first time. The pump source was a single-frequency Ho:YLF laser and amplifier system, which was locked to the 2064 nm absorption line of HBr. Laser oscillation was demonstrated on 19 molecular transition lines, which included both the R-branch (3870-4015 nm) and the P-branch (4070-4453 nm), by the use of an intra-cavity diffraction grating. The highest output energy was 2.4 mJ at 4133 nm. PMID:24978537

  14. Multi-coupler side-pumped Yb-doped double-clad fiber laser

    NASA Astrophysics Data System (ADS)

    Ou, Pan; Yan, Ping; Gong, Mali; Wei, Wenlou

    2004-05-01

    The side-coupler of angle polished method, using angle-polished multimode fiber and optical adhesive, is used to efficiently pump an Yb-doped double-clad fiber laser. The maximum coupling efficiency of 78.6% is achieved by the side-coupler for a multimode fiber with a circular core of 200 um and a double-clad fiber with a 350/400 um D-shaped inner cladding. While laser diodes (LDs) with three side-couplers are simultaneously used as pump sources, maximum output power of 1.38 W and slope efficiency of 48.9% are demonstrated in the fiber laser system.

  15. Absorption-heat-pump system

    DOEpatents

    Grossman, G.; Perez-Blanco, H.

    1983-06-16

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  16. Solar-pumped Nd:Cr:GSGG parallel array laser

    NASA Astrophysics Data System (ADS)

    Thompson, George A.; Krupkin, V.; Yogev, Amnon; Oron, Moshe

    1992-12-01

    A compact, parallel array of three Nd:Cr:GSGG laser rods is used to construct a quasi-CW laser. The array is pumped by concentrated solar light and is mounted in a single concentrator. The three laser rods use a common pair of laser mirrors to define the optical resonator. The three laser beams are not coherently coupled in these experiments. The simplicity of the design, and its reasonable stability in terms of vibration and optical misalignment, suggest that the design may be scalable for higher power.

  17. Screw-fed pump system

    SciTech Connect

    Sprouse, Kenneth M

    2014-11-25

    A pump system includes a pump that includes a first belt and a second belt that are spaced apart from each other to provide generally straight sides of a passage there between. There is an inlet at one end of the passage and an outlet at an opposite end of the passage, with a passage length that extends between the inlet and the outlet. The passage defines a gap distance in a width direction between the straight sides at the passage inlet. A hopper includes an interior space that terminates at a mouth at the passage inlet. At least one screw is located within the interior space of the hopper and includes a screw diameter in the width direction that is less than or equal to the gap distance.

  18. Pump efficiency in solar-energy systems

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Study investigates characteristics of typical off-the-shelf pumping systems that might be used in solar systems. Report includes discussion of difficulties in predicting pump efficiency from manufacturers' data. Sample calculations are given. Peak efficiencies, flow-rate control, and noise levels are investigated. Review or theory of pumps types and operating characteristics is presented.

  19. Axial pumps for propulsion systems

    NASA Technical Reports Server (NTRS)

    Huppert, M. C.; Rothe, K.

    1974-01-01

    The development of axial flow hydrogen pumps is examined. The design features and the performance data obtained during the course of the development programs are discussed. The problems created by the pump characteristics are analyzed. Graphs of four stage pump performance for various turbine blade configurations are developed. The characteristics and performance of a variety of pumps are included.

  20. Laser-diode pumped 40-W Yb:YAG ceramic laser.

    PubMed

    Hao, Qiang; Li, Wenxue; Pan, Haifeng; Zhang, Xiaoyi; Jiang, Benxue; Pan, Yubai; Zeng, Heping

    2009-09-28

    We demonstrated a high-power continuous-wave (CW) polycrystalline Yb:YAG ceramic laser pumped by fiber-pigtailed laser diode at 968 nm with 400 mum fiber core. The Yb:YAG ceramic laser performance was compared for different Yb(3+) ion concentrations in the ceramics by using a conventional end-pump laser cavity consisting of two flat mirrors with output couplers of different transmissions. A CW laser output of 40 W average power with M(2) factor of 5.8 was obtained with 5 mol% Yb concentration under 120 W incident pump power. This is to the best of our knowledge the highest output power in end-pumped bulk Yb:YAG ceramic laser. PMID:19907559

  1. Compact laser amplifier system

    DOEpatents

    Carr, R.B.

    1974-02-26

    A compact laser amplifier system is described in which a plurality of face-pumped annular disks, aligned along a common axis, independently radially amplify a stimulating light pulse. Partially reflective or lasing means, coaxially positioned at the center of each annualar disk, radially deflects a stimulating light directed down the common axis uniformly into each disk for amplification, such that the light is amplified by the disks in a parallel manner. Circumferential reflecting means coaxially disposed around each disk directs amplified light emission, either toward a common point or in a common direction. (Official Gazette)

  2. Improved performance of high average power semiconductor arrays for applications in diode pumped solid state lasers

    SciTech Connect

    Beach, R.; Emanuel, M.; Benett, W.; Freitas, B.; Ciarlo, D.; Carlson, N.; Sutton, S.; Skidmore, J.; Solarz, R.

    1994-01-01

    The average power performance capability of semiconductor diode laser arrays has improved dramatically over the past several years. These performance improvements, combined with cost reductions pursued by LLNL and others in the fabrication and packaging of diode lasers, have continued to reduce the price per average watt of laser diode radiation. Presently, we are at the point where the manufacturers of commercial high average power solid state laser systems used in material processing applications can now seriously consider the replacement of their flashlamp pumps with laser diode pump sources. Additionally, a low cost technique developed and demonstrated at LLNL for optically conditioning the output radiation of diode laser arrays has enabled a new and scalable average power diode-end-pumping architecture that can be simply implemented in diode pumped solid state laser systems (DPSSL`s). This development allows the high average power DPSSL designer to look beyond the Nd ion for the first time. Along with high average power DPSSL`s which are appropriate for material processing applications, low and intermediate average power DPSSL`s are now realizable at low enough costs to be attractive for use in many medical, electronic, and lithographic applications.

  3. X-ray-pumped Cr,Nd:GSGG laser

    NASA Astrophysics Data System (ADS)

    Brannon, Paul J.; Hedemann, M. A.; Weichman, Louis S.

    1996-03-01

    It has been demonstrated that x rays alone can be used to pump a 1061 nm Cr,Nd:GSGG laser. Lasing action has been observed when the laser rod absorbs greater than 27 krad of 2 MeV x rays. The laser cavity consists of a corner cube and an output mirror with a reflectivity of 67%. The x rays are delivered in a 20 ns pulse, and laser action is observed several microseconds after the x ray pulse. This delay suggests that chromium is important in the laser pumping process since it is known that an excited chromium ion takes about 10 microseconds to transfer its energy to a neodymium ion.

  4. Dynamics of flashlamp pumping a Nd:Cr:GSGG laser

    NASA Astrophysics Data System (ADS)

    Pack, Michael V.; Miller, Paul A.; Shelton, Jason

    2008-08-01

    We investigate the inversion dynamics in Nd:Cr:GSGG laser rods as a function of pumping frequency in order to optimize Nd:Cr:GSGG Q switched lasers for rapid time to fire applications. By frequency filtering the pump light to the Nd:Cr:GSGG rod and measuring the florescence from the rod, we determine the dynamics for different excitation processes in the laser (i.e. direct excitation of the Nd ions or indirect excitation via Cr ions). We also measure the flashlamp pulse shape using various spectral filters This combination of measurements help us understand the processes contributing and limiting the efficiency of Nd:Cr:GSGG lasers when the lasers must fire on a short time scale.

  5. Potential of solar-simulator-pumped alexandrite lasers

    NASA Technical Reports Server (NTRS)

    Deyoung, Russell J.

    1990-01-01

    An attempt was made to pump an alexandrite laser rod using a Tamarak solar simulator and also a tungsten-halogen lamp. A very low optical laser cavity was used to achieve the threshold minimum pumping-power requirement. Lasing was not achieved. The laser threshold optical-power requirement was calculated to be approximately 626 W/sq cm for a gain length of 7.6 cm, whereas the Tamarak simulator produces 1150 W/sq cm over a gain length of 3.3 cm, which is less than the 1442 W/sq cm required to reach laser threshold. The rod was optically pulsed with 200 msec pulses, which allowed the alexandrite rod to operate at near room temperature. The optical intensity-gain-length product to achieve laser threshold should be approximately 35,244 solar constants-cm. In the present setup, this product was 28,111 solar constants-cm.

  6. High Power 938nm Cladding Pumped Fiber Laser

    SciTech Connect

    Dawson, J; Beach, R; Brobshoff, A; Liao, Z; Payne, S; Pennington, D; Taylor, L; Hackenberg, W; Bonaccini, D

    2002-12-26

    We have developed a Nd:doped cladding pumped fiber amplifier, which operates at 938nm with greater than 2W of output power. The core co-dopants were specifically chosen to enhance emission at 938nm. The fiber was liquid nitrogen cooled in order to achieve four-level laser operation on a laser transition that is normally three level at room temperature, thus permitting efficient cladding pumping of the amplifier. Wavelength selective attenuation was induced by bending the fiber around a mandrel, which permitted near complete suppression of amplified spontaneous emission at 1088nm. We are presently seeking to scale the output of this laser to 10W. We will discuss the fiber and laser design issues involved in scaling the laser to the 10W power level and present our most recent results.

  7. Direct solar pumping of semiconductor lasers: A feasibility study

    NASA Technical Reports Server (NTRS)

    Anderson, Neal G.

    1991-01-01

    The primary goals of the feasibility study are the following: (1) to provide a preliminary assessment of the feasibility of pumping semiconductor lasers in space directly focused sunlight; and (2) to identify semiconductor laser structures expected to operate at the lowest possible focusing intensities. It should be emphasized that the structures under consideration would provide direct optical-to-optical conversion of sunlight into laser light in a single crystal, in contrast to a configuration consisting of a solar cell or battery electrically pumping a current injection laser. With external modulation, such lasers may prove to be efficient sources for intersatellite communications. We proposed to develop a theoretical model of semiconductor quantum-well lasers photopumped by a broadband source, test it against existing experimental data where possible, and apply it to estimating solar pumping requirements and identifying optimum structures for operation for operation at low pump intensities. This report outlines our progress toward these goals. Discussion of several technical details are left to the attached summary abstract.

  8. High power, high efficiency diode pumped Raman fiber laser

    NASA Astrophysics Data System (ADS)

    Glick, Yaakov; Fromzel, Viktor; Zhang, Jun; Dahan, Asaf; Ter-Gabrielyan, Nikolay; Pattnaik, Radha K.; Dubinskii, Mark

    2016-06-01

    We demonstrate a high power high efficiency Raman fiber laser pumped directly by a laser diode module at 976 nm. 80 Watts of CW power were obtained at a wavelength of 1020 nm with an optical-to-optical efficiency of 53%. When working quasi-CW, at a duty cycle of 30%, 85 W of peak power was produced with an efficiency of 60%. A commercial graded-index (GRIN) core fiber acts as the Raman fiber in a power oscillator configuration, which includes spectral selection to prevent generation of the 2nd Stokes. In addition, significant brightness enhancement of the pump beam is attained due to the Raman gain distribution profile in the GRIN fiber. To the best of our knowledge, this is the highest power Raman fiber laser directly pumped by laser diodes, which also exhibits a record efficiency for such a laser. In addition, it is the highest power Raman fiber laser (regardless of pumping source) demonstrated based on a GRIN fiber.

  9. Nuclear pumped electronic transition laser studies

    NASA Technical Reports Server (NTRS)

    Hughes, W. M.; Helmick, H. H.

    1979-01-01

    An experiment is proposed that should yield unambiguous absolute results on the production efficiency of rare gas excimers from fission fragments. Laser threshold efficiency is parameterized and calculations indicate that some lasers can be operated using relatively simple experimental apparatus adjacent to GODIVA. Operation of a KrF excimer laser adjacent to GODIVA appears to be possible, although the neutron pulse width is not well matched to the laser pulse duration. However, calculation indicates that KrF excimer laser output on the order of a joule may be possible.

  10. High power continuous-wave Alexandrite laser with green pump

    NASA Astrophysics Data System (ADS)

    Ghanbari, Shirin; Major, Arkady

    2016-07-01

    We report on a continuous-wave (CW) Alexandrite (Cr:BeAl2O4) laser, pumped by a high power green source at 532 nm with a diffraction limited beam. An output power of 2.6 W at 755 nm, a slope efficiency of 26%, and wavelength tunability of 85 nm have been achieved using 11 W of green pump. To the best of our knowledge, this is the highest CW output power of a high brightness laser pumped Alexandrite laser reported to date. The results obtained in this experiment can lead to the development of a high power tunable CW and ultrafast sources of the near-infrared or ultraviolet radiation through frequency conversion.

  11. A computational model for transient temperature rise in a dye laser gain medium pumped by a copper vapor laser

    NASA Astrophysics Data System (ADS)

    Rawat, V. S.; Gantayet, L. M.; Sridhar, G.; Singh, S.

    2014-02-01

    Spectrally stable dye lasers play an important role in techniques based on high resolution spectroscopy and atomic spectroscopy. The spectral purity of a dye laser is affected when the pump power to it is increased beyond the threshold. When the pump power is increased beyond the threshold, two mode oscillations occur which decrease the spectral purity of the dye laser. The effect of higher pump pulse energies on transient thermal effects has been studied using a computational fluid dynamics (CFD) model and the disturbances to the laser cavity have been studied using commercially available ray tracing software. The change in the cavity length was determined from the CFD model for several dye concentrations and pump powers. The results of the CFD model have been verified by published results and experimental results from our system. Our study shows that in the longitudinally pumped single mode laser change in the cavity length is a more dominant disturbance than thermal blooming. Our model is useful for the design of the dye cell.

  12. Laser spark distribution and ignition system

    DOEpatents

    Woodruff, Steven; McIntyre, Dustin L.

    2008-09-02

    A laser spark distribution and ignition system that reduces the high power optical requirements for use in a laser ignition and distribution system allowing for the use of optical fibers for delivering the low peak energy pumping pulses to a laser amplifier or laser oscillator. An optical distributor distributes and delivers optical pumping energy from an optical pumping source to multiple combustion chambers incorporating laser oscillators or laser amplifiers for inducing a laser spark within a combustion chamber. The optical distributor preferably includes a single rotating mirror or lens which deflects the optical pumping energy from the axis of rotation and into a plurality of distinct optical fibers each connected to a respective laser media or amplifier coupled to an associated combustion chamber. The laser spark generators preferably produce a high peak power laser spark, from a single low power pulse. The laser spark distribution and ignition system has application in natural gas fueled reciprocating engines, turbine combustors, explosives and laser induced breakdown spectroscopy diagnostic sensors.

  13. An economic evaluation comparison of solar water pumping system with engine pumping system for rice cultivation

    NASA Astrophysics Data System (ADS)

    Treephak, Kasem; Thongpron, Jutturit; Somsak, Dhirasak; Saelao, Jeerawan; Patcharaprakiti, Nopporn

    2015-08-01

    In this paper we propose the design and economic evaluation of the water pumping systems for rice cultivation using solar energy, gasoline fuel and compare both systems. The design of the water and gasoline engine pumping system were evaluated. The gasoline fuel cost used in rice cultivation in an area of 1.6 acres. Under same conditions of water pumping system is replaced by the photovoltaic system which is composed of a solar panel, a converter and an electric motor pump which is compose of a direct current (DC) motor or an alternating current (AC) motor with an inverter. In addition, the battery is installed to increase the efficiency and productivity of rice cultivation. In order to verify, the simulation and economic evaluation of the storage energy battery system with batteries and without batteries are carried out. Finally the cost of four solar pumping systems was evaluated and compared with that of the gasoline pump. The results showed that the solar pumping system can be used to replace the gasoline water pumping system and DC solar pump has a payback less than 10 years. The systems that can payback the fastest is the DC solar pumping system without batteries storage system. The system the can payback the slowest is AC solar pumping system with batteries storage system. However, VAC motor pump of 220 V can be more easily maintained than the motor pump of 24 VDC and batteries back up system can supply a more stable power to the pump system.

  14. Laser system with trivalent chromium doped aluminum tungstate fluorescent converter

    SciTech Connect

    Dube, G.

    1988-09-06

    This patent describes a laser system combination comprising: (a) a neodymium element; (b) a light source for pumping the neodymium laser element to produce coherent, monochromatic light; (c) a fluorescent converter element positioned in light exchange relationship with the light source for spectrally shifting at least a portion of light outside of the neodymium laser pumping band passing through the neodymium laser into light in the neodymium laser pumping band; (d) the fluorescent element including trivalent chromium doped aluminum tungstate excited by light passing through the laser which is outside of the pumping band for the laser, the tungstate covering a portion of light passing through the laser element which is outside of the pumping band into light within the pumping band; (e) the concentration of the trivalent chromium dopant lying in the range of 0.5 to 3 per mole percent (%).

  15. 1.3 µm Raman-bismuth fiber amplifier pumped by semiconductor disk laser.

    PubMed

    Chamorovskiy, A; Rautiainen, J; Rantamäki, A; Golant, K M; Okhotnikov, O G

    2011-03-28

    A hybrid Raman-bismuth fiber amplifier pumped in co-propagation configuration by a single 1.22 µm semiconductor disk laser is presented. The unique attribute of this dual-gain system is that both amplifiers require the pump source with the same wavelength because pump-Stokes spectral shift in 1.3 µm Raman amplifier and pump-gain bandwidth separation in 1.3 µm bismuth fiber amplifier have the same value. Residual pump power at the output of Raman amplifier in this scheme is efficiently consumed by bismuth-doped fiber thus increasing the overall conversion efficiency. The small-signal gain of 18 dB at 1.3 W of pump power has been achieved for hybrid scheme which is by 9 dB higher as compared with isolated Raman amplifier without bismuth fiber. Low noise performance of pump semiconductor disk laser with RIN of -150 dB/Hz combined with nearly diffraction-limited beam quality and Watt-level output powers allows for efficient core-pumping of a single-mode fiber amplifier systems and opens up new opportunities for amplification in O-band spectral range. PMID:21451671

  16. A compact spin-exchange optical pumping system for 3He polarization based on a solenoid coil, a VBG laser diode, and a cosine theta RF coil

    NASA Astrophysics Data System (ADS)

    Lee, Sungman; Kim, Jongyul; Moon, Myung Kook; Lee, Kye Hong; Lee, Seung Wook; Ino, Takashi; Skoy, Vadim R.; Lee, Manwoo; Kim, Guinyun

    2013-02-01

    For use as a neutron spin polarizer or analyzer in the neutron beam lines of the HANARO (High-flux Advanced Neutron Application ReactOr) nuclear research reactor, a 3He polarizer was designed based on both a compact solenoid coil and a VBG (volume Bragg grating) diode laser with a narrow spectral linewidth of 25 GHz. The nuclear magnetic resonance (NMR) signal was measured and analyzed using both a built-in cosine radio-frequency (RF) coil and a pick-up coil. Using a neutron transmission measurement, we estimated the polarization ratio of the 3He cell as 18% for an optical pumping time of 8 hours.

  17. Broadly tunable, longitudinally diode-pumped Alexandrite laser

    NASA Astrophysics Data System (ADS)

    Strotkamp, M.; Witte, U.; Munk, A.; Hartung, A.; Gausmann, S.; Hengesbach, S.; Traub, M.; Hoffmann, H.-D.; Hoeffner, J.; Jungbluth, B.

    2014-02-01

    We present design and first performance data of a broadly tunable Alexandrite laser longitudinally pumped by a newly developed high brightness single emitter diode laser module with output in the red spectral range. Replacing the flashlamps, which are usually used for pumping Alexandrite, will increase the efficiency and maintenance interval of the laser. The pump module is designed as an optical stack of seven single-emitter laser diodes. We selected an optomechanical concept for the tight overlay of the radiation using a minimal number of optical components for collimation, e.g. a FAC and a SAC lens, and focusing. The module provides optical output power of more than 14 W (peak pulse output in the focus) with a beam quality of M2 = 41 in the fast axis and M2 = 39 in the slow axis. The Alexandrite crystal is pumped from one end at a repetition rate of 35 Hz and 200μs long pump pulses. The temperature of the laser crystal can be tuned to between 30 °C and 190 °C using a thermostat. The diode-pumped Alexandrite laser reaches a maximum optical-optical efficiency of 20 % and a slope efficiency of more than 30 % in fundamental-mode operation (M2 < 1.10). When a Findlay-Clay analysis with four different output couplers is conducted, the round-trip loss of the cavity is determined to be around 1 %. The wavelength is tunable to between 755 and 788 nm via crystal temperature or between 745 and 805 nm via an additional Brewster prism.

  18. 3 μm diode-pumped solid state erbium laser for cataract surgery

    NASA Astrophysics Data System (ADS)

    Ernst, Holger; Ertmer, Wolfgang; Lubatschowski, Holger

    2003-06-01

    To improve the efficiency of laser phacoemulsification we developed a compact, high-repetition-rate, high-average-power, diode-pumped, 2.94 μm TIR-cavity Er:YAG laser system. Laser parameters of 19.4% slope efficiency, 5 W of average output power at up to 300 Hz repetition rate and more than 1.5 W at 1 kHz are demonstrated. The special design results in low thermal lenses of 1.9 Dpt/W. This is a good condition for high laser system scalability.

  19. New class of compact diode pumped sub 10-fs lasers for biomedical applications

    NASA Astrophysics Data System (ADS)

    Le, T.; Müller, A.; Sumpf, B.; Jensen, O. B.; Hansen, A. K.; Andersen, P. E.

    2016-03-01

    Diode-pumping Ti:sapphire lasers promises a new approach to low-cost femtosecond light sources. Thus in recent years much effort has been taken just to overcome the quite low power and low beam qualities of available green diodes to obtain output powers of several hundred milliwatts from a fs-laser. In this work we present an alternative method by deploying frequency-doubled IR diodes with good beam qualities to pump fs-lasers. The revolutionary approach allows choosing any pump wavelengths in the green region and avoids complicated relay optics for the diodes. For the first time we show results of a diode-pumped 10 fs-laser and how a single diode setup can be integrated into a 30 x 30 cm2 fs-laser system generating sub 20 fs laser pulses with output power towards half a Watt. This technology paves the way for a new class of very compact and cost-efficient fs-lasers for life science and industrial applications.

  20. Possibility of nuclear pumped laser experiment using low enriched uranium

    SciTech Connect

    Obara, Toru; Takezawa, Hiroki

    2012-06-06

    Possibility to perform experiments for nuclear pumped laser oscillation by using low enriched uranium is investigated. Kinetic analyses are performed for two types of reactor design, one is using highly enriched uranium and the other is using low enriched uranium. The reactor design is based on the experiment reactor in IPPE. The results show the oscillation of nuclear pumped laser in the case of low enriched uranium reactor is also possible. The use of low enriched uranium in the experiment will make experiment easier.

  1. Graphene surface emitting terahertz laser: Diffusion pumping concept

    SciTech Connect

    Davoyan, Arthur R.; Morozov, Mikhail Yu.; Popov, Vyacheslav V.; Satou, Akira; Otsuji, Taiichi

    2013-12-16

    We suggest a concept of a tunable graphene-based terahertz (THz) surface emitting laser with diffusion pumping. We employ significant difference in the electronic energy gap of graphene and a typical wide-gap semiconductor, and demonstrate that carriers generated in the semiconductor can be efficiently captured by graphene resulting in population inversion and corresponding THz lasing from graphene. We develop design principles for such a laser and estimate its performance. We predict up to 50 W/cm{sup 2} terahertz power output for 100 kW/cm{sup 2} pump power at frequency around 10 THz at room temperature.

  2. Threshold kinetics of a solar-simulator-pumped iodine laser

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Lee, Y.; Weaver, W. R.; Humes, D. H.; Lee, J. H.

    1984-01-01

    A model of the chemical kinetics of the n-C3F7I solar-simulator-pumped iodine laser is utilized to study the major kinetic processes associated with the threshold behavior of this experimental system. Excited-state diffusion to the cell wall is the dominant limiting factor below 5 torr. Excited-state diffusion to the cell wall is the dominant limiting factor below 5 torr. Excited-state recombination with the alkyl radical and quenching by the parent gas control threshold at higher pressures. Treatment of the hyperfine splitting and uncertainty in the pressure broadening are important factors in fixing the threshold level. In spite of scatter in the experimental data caused by instabilities in the simulator high-pressure high-pressure arc, reasonable agreement is achieved between the model and experiment. Model parameters arrived at are within the uncertainty range of values found in the literature.

  3. Optimization of rod diameter in solid state lasers side pumped with multiple laser diode arrays

    NASA Technical Reports Server (NTRS)

    Sims, Newton, Jr.; Chamblee, Christyl M.; Barnes, Norman P.; Lockard, George E.; Cross, Patricia L.

    1992-01-01

    Results of a study to determine the optimum laser rod diameter for maximum output energy in a solid state neodymium laser transversely pumped with multiple laser diode arrays are reported here. Experiments were performed with 1.0 mm, 1.5 mm and 2.0 mm rod radii of both neodymium doped Y3Al5O12 (Nd:YAG) and La2Be2O5 (Nd:BeL) pumped with laser diode arrays having a maximum combined energy of 10.5 mJ. Equations were derived which predict the optimum rod radius and corresponding output mirror reflectivity for a given laser material and total pump energy. Predictions of the equations agreed well with the experiments for each of the laser materials which possessed significantly different laser properties from one another.

  4. Diode-Pumped, Q-Switched, Frequency-Doubling Laser

    NASA Technical Reports Server (NTRS)

    Hemmati, Hamid; Lesh, James R.

    1993-01-01

    Experimental Q-switched, diode-pumped, intracavity-frequency-doubling laser generates pulses of radiation at wavelength of 532 nm from excitation at 810 nm. Principal innovative feature distinguishing laser from others of its type: pulsed operation of laser at pulse-repetition frequencies higher than reported previously. Folded resonator keeps most of second-harmonic radiation away from Q-switcher, laser crystal, and laser diodes. Folding mirror highly reflective at fundamental laser wavelength and highly transmissive at second-harmonic laser wavelength. By virtue of difference of about 0.6 percent between reflectivities in two polarizations at fundamental wavelength, folding mirror favors polarized oscillation at fundamental wavelength. This characteristic desirable for doubling of frequency in some intracavity crystals.

  5. Intensity and absorbed-power distribution in a cylindrical solar-pumped dye laser

    NASA Technical Reports Server (NTRS)

    Williams, M. D.

    1984-01-01

    The internal intensity and absorbed-power distribution of a simplified hypothetical dye laser of cylindrical geometry is calculated. Total absorbed power is also calculated and compared with laboratory measurements of lasing-threshold energy deposition in a dye cell to determine the suitability of solar radiation as a pump source or, alternatively, what modifications, if any, are necessary to the hypothetical system for solar pumping.

  6. Nonlinear fibre-optic devices pumped by semiconductor disk lasers

    SciTech Connect

    Chamorovskiy, A Yu; Okhotnikov, Oleg G

    2012-11-30

    Semiconductor disk lasers offer a unique combination of characteristics that are particularly attractive for pumping Raman lasers and amplifiers. The advantages of disk lasers include a low relative noise intensity (-150 dB Hz{sup -1}), scalable (on the order of several watts) output power, and nearly diffraction-limited beam quality resulting in a high ({approx}70 % - 90 %) coupling efficiency into a single-mode fibre. Using this technology, low-noise fibre Raman amplifiers operating at 1.3 {mu}m in co-propagation configuration are developed. A hybrid Raman-bismuth doped fibre amplifier is proposed to further increase the pump conversion efficiency. The possibility of fabricating mode-locked picosecond fibre lasers operating under both normal and anomalous dispersion is shown experimentally. We demonstrate the operation of 1.38-{mu}m and 1.6-{mu}m passively mode-locked Raman fibre lasers pumped by 1.29-{mu}m and 1.48-{mu}m semiconductor disk lasers and producing 1.97- and 2.7-ps pulses, respectively. Using a picosecond semiconductor disk laser amplified with an ytterbium-erbium fibre amplifier, the supercontinuum generation spanning from 1.35 {mu}m to 2 {mu}m is achieved with an average power of 3.5 W. (invited paper)

  7. The SLAC polarized electron source laser system

    SciTech Connect

    Frisch, J.

    1995-10-01

    The Stanford Linear Collider (SLC) has operated a polarized photocathode electron source and titanium sapphire laser for high energy physics collisions for over 6,500 hours of nearly continuous operation. The laser system for the source has demonstrated > 98.5% total uptime for the duration of the experiment. The laser system uses a pair of titanium sapphire oscillators pumped by frequency doubled YAG lasers to produce 2ns, 250 {micro}J pulses at wavelengths from 740nm to 870nm.

  8. Theoretical Modeling of the Discharge-Pumped Xenon - Excimer Laser.

    NASA Astrophysics Data System (ADS)

    Zhu, Sheng-Bai

    The present dissertation is dedicated to a theoretical study of the discharge pumped XeCl excimer laser. For a better description of our system, Two modelings which supplement each other from different angles have been successfully developed. The first one, a comprehensive kinetics model which can be applied to the detailed simulations of the temporal behavior of the discharge characteristics and laser performance, is constructed by a set of coupled first -order differential equations, such as the rate equations, the Boltzmann equation, the external electric circuit equations, the energy balance equation, and the equations of optical resonator. The starting and termination of the discharge are taken into deliberation for the first time, especially for the Blumlein case. Some 70 kinetic processes and 23 chemical species are included. Such a problem can only be numerically solved by means of an elaborate computer code. Another model, on the other hand, pays attention to the quasi-steady-state to facilitate parametric study. A group of rate coefficients for the kinetic processes involving free electrons are approximated by analytic expressions using numerical results compiled from computer code calculations. Explicit expressions of the number densities for all relevant chemical species are obtained. Among them, HCI(O), H, and Cl can never reach steady-state population. Time history of the concentrations for these species are computed instead. With the discussions about the effect of vibrational relaxation and state-to-state transfer in the upper energy level, and the discussions about the rotational structure, collisional broadening, and dissociation of the diatomic ground state, we have extensively investigated the spontaneous emission spectra, the small-signal gain, the non-saturable absorption, the steady-state laser output power, and various efficiencies. Saturation effects in laser oscillators and laser amplifiers are discussed as well. These topics relate to the

  9. Temperature distribution of laser crystal in LD end-pumped Nd:YAG/LBO blue laser

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Zheng, Yibo; Li, Simian; Jia, Liping; Kang, Junjian

    2012-11-01

    In this study, LD end-pumped Nd:YAG/LBO solid state blue laser is realized by even hollow cavity. A thermal distribution model of Nd:YAG crystal is established. Based on the calculation, the temperature distribution of laser crystal is obtained. The results show that the temperature decreases from the pump end to the launch end exponentially. When the pumping power is 10 W and the radius of pumping beams is 240μm, a biggest output power 1.06 W of blue light is achieved, giving an optical conversion efficiency of 10.6%.

  10. Vertical cavity surface-emitting semiconductor lasers with injection laser pumping

    NASA Astrophysics Data System (ADS)

    McDaniel, D. L., Jr.; McInerney, J. G.; Raja, M. Y. A.; Schaus, C. F.; Brueck, S. R. J.

    1990-05-01

    Continuous-wave GaAs/GaAlAs edge-emitting diode lasers were used to pump GaAs/AlGaAs and InGaAs/AlGaAs vertical cavity surface-emitting lasers (VCSELs) with resonant periodic gain (RPG) at room temperature. Pump threshold as low as 11 mW, output powers as high as 27 mW at 850 nm, and external differential quantum efficiencies of about 70 percent were observed in GaAs/AlGaAs surface -emitters; spectral brightness 22 times that of the pump laser was also observed. Output powers as high as 85 mW at 950 nm and differential quantum efficiencies of up to 58 percent were recorded for the InGaAs surface-emitting laser. This is the highest quasi-CW output power ever reported for any RPG VCSEL, and the first time such a device has been pumped using an injection laser diode.

  11. Femtosecond mode-locked holmium fiber laser pumped by semiconductor disk laser.

    PubMed

    Chamorovskiy, A; Marakulin, A V; Ranta, S; Tavast, M; Rautiainen, J; Leinonen, T; Kurkov, A S; Okhotnikov, O G

    2012-05-01

    We report on a 2085 nm holmium-doped silica fiber laser passively mode-locked by semiconductor saturable absorber mirror and carbon nanotube absorber. The laser, pumped by a 1.16 μm semiconductor disk laser, produces 890 femtosecond pulses with the average power of 46 mW and the repetition rate of 15.7 MHz. PMID:22555700

  12. High-Efficiency 894-nm Laser Emission of Laser-Diode-Bar-Pumped Cesium-Vapor Laser

    NASA Astrophysics Data System (ADS)

    Zheng, Yujin; Niigaki, Minoru; Miyajima, Hirofumi; Hiruma, Teruo; Kan, Hirofumi

    2009-03-01

    We report a high-efficiency cesium-vapor laser with a high-gas-pressure (˜3-atm helium and 0.49-atm ethane) cell pumped by a high-power external-cavity laser-diode bar. Peak laser power of 12.1 W at 894 nm was obtained, when the absorbed peak pump power was 23.1 W. The achieved slope efficiencies with the incident pump power and the absorbed pump power were 33 and 81.7%, respectively.

  13. Ultra high brightness laser diode arrays for pumping of compact solid state lasers and direct applications

    NASA Astrophysics Data System (ADS)

    Kohl, Andreas; Fillardet, Thierry; Laugustin, Arnaud; Rabot, Olivier

    2012-10-01

    High Power Laser Diodes (HPLD) are increasingly used in different fields of applications such as Industry, Medicine and Defense. Our significant improvements of performances (especially in power and efficiency) and a reproducible manufacturing process have led to reliable, highly robust components. For defense and security applications these devices are used predominantly for pumping of solid state lasers (ranging, designation, countermeasures, and sensors). Due to the drastically falling price per watt they are more and more replacing flash lamps as pump sources. By collimating the laser beam even with a bar to bar pitch of only 400μm. cutting edge brightness of our stacks.is achieved Due the extremely high brightness and high power density these stacks are an enabling technology for the development of compact highly efficient portable solid state lasers for applications as telemeters and designators on small platforms such as small UAVs and handheld devices. In combination with beam homogenizing optics their compact size and high efficiency makes these devices perfectly suited as illuminators for portable active imaging systems. For gated active imaging systems a very short pulse at high PRF operation is required. For this application we have developed a diode driver board with an efficiency several times higher than that of a standard driver. As a consequence this laser source has very low power consumption and low waste heat dissipation. In combination with its compact size and the integrated beam homogenizing optics it is therefore ideally suited for use in portable gated active imaging systems. The kWatt peak power enables a range of several hundred meters. The devices described in this paper mostly operate at wavelength between 800 nm and 980nm. Results from diodes operating between 1300 nm and 1550 nm are presented as well.

  14. Solar-simulator-pumped atomic iodine laser kinetics

    NASA Technical Reports Server (NTRS)

    Wilson, H. W.; Raju, S.; Shiu, Y. J.

    1983-01-01

    The literature contains broad ranges of disagreement in kinetic data for the atomic iodine laser. A kinetic model of a solar-simulator-pumped iodine laser is used to select those kinetic data consistent with recent laser experiments at the Langley Research Center. Analysis of the solar-simulator-pumped laser experiments resulted in the following estimates of rate coefficients: for alkyl radical (n-C3F7) and atomic iodine (I) recombination, 4.3 x 10 to the 11th power (1.9) + or - cu cm/s; for n-C3F7I stabilized atomic iodine recombination (I + I) 3.7 x 10 to the -32nd power (2.3) + or -1 cm to the 6th power/s; and for molecular iodine (I2) quenching, 3.1 x 10 to the -11th power (1.6) + or - 1 cu cm/s. These rates are consistent with the recent measurements.

  15. Narrow spectral width laser diode for metastable argon atoms pumping

    NASA Astrophysics Data System (ADS)

    Gao, Jun; Li, Bin; Wang, Xinbing; Zuo, Duluo

    2016-03-01

    Diode laser pump source with narrow emitting spectrum for optically pumped metastable rare gas laser (OPRGL) of argon was achieved by employing a complex external cavity coupled with volume Bragg grating (VBG). A commercially available c-mount laser diode with rated power of 6 W was used and studied in both the free running mode and VBG external cavity. The maximum output power of 3.9 W with FWHM less than 25 pm and peak wavelength locked around 811.53 nm was obtained from the VBG external cavity laser diode. Precise control of VBG temperature enabled fine tuning of the emission wavelength over a range of 450 pm. Future researches on OPRGL of argon will benefit from it.

  16. LED pumped Nd:YAG laser development program

    NASA Technical Reports Server (NTRS)

    Farmer, G. I.; Kiang, Y. C.; Lynch, R. J.

    1973-01-01

    The results of a development program for light emitting diode (LED) pumped Nd:YAG lasers are described. An index matching method to increase the coupling efficiency of the laser is described. A solid glass half-cylinder of 5.0 by 5.6 centimeters was used for index matching and also as a pumping cavity reflector. The laser rods were 1.5 by 56 millimeters with dielectric coatings on both end surfaces. The interfaces between the diode array, glass cylinder, and laser rod were filled with viscous fluid of refractive index n = 1.55. Experiments performed with both the glass cylinder and a gold coated stainless steel reflector of the same dimensions under the same operating conditions indicate that the index matching cylinder gave 159 to 200 percent improvement of coupling efficiency over the metal reflector at various operating temperatures.

  17. Advances in NASA research on nuclear-pumped lasers

    NASA Technical Reports Server (NTRS)

    De Young, R. J.

    1982-01-01

    NASA has been primarily interested in nuclear-pumped lasers using the He-3 or U-235F6 reaction for lasant excitation. With He-3 excitation, a large volume, multiple-path He-3-Ar nuclear laser has produced an output of 1 kilowatt. Power deposition was shown to be homogeneous over this volume. The CO laser has been pumped for the first time using the He-3 reaction, producing approximately 200 Watts. Using a boron-10 coating to excite N2, nuclear lasing has been achieved in CO2 in a transfer laser configuration. Nuclear lasing of Ar-Xe has been demonstrated using fission fragment excitation from U-235F6. Research on the gas core reactor has resulted in a steady state operational power of 30 kilowatts with flowing U-235F6 in an argon vortex.

  18. Formation of laser irradiation by non-uniform pumping discharge of KrF laser

    NASA Astrophysics Data System (ADS)

    Bychkov, Yurii I.; Panchenko, Yurii N.; Yampolskaya, Sofiya A.; Yastremskii, Arcadii G.

    2015-12-01

    Results of 2D simulation of a KrF laser are presented. In the model, inhomogeneities of distributions of the electric field and plasma particle concentration are considered. It is demonstrated, that the laser energy depends not only on the value of the total pump power, but also from its spatial distribution. The shape of the electrodes is a major determinant of the spatial distribution of pumping power in the active medium. For electrodes with small radii of curvature, the pumping power in the center of the discharge may be too high. This leads to the suppression of radiation in the center of the discharge and the limitation of the laser energy.

  19. Fiber-laser pumped actively Q-switched Er:LuYAG laser at 1648 nm

    NASA Astrophysics Data System (ADS)

    Yang, X. F.; Wang, Y.; Zhao, T.; Zhu, H. Y.; Shen, D. Y.

    2016-02-01

    We demonstrated an acousto-optic Q-switched 1648 nm Er:LuYAG laser resonantly pumped by a cladding-pumped Er,Yb fiber laser at 1532 nm. Stable Q-switching operation was obtained with the pulse repetition rate (PRR) varying from 200 Hz to 10 kHz. At PRR of 200 Hz, the laser yielded Q-switched pulses with 3.3 mJ pulse energy and 65 ns pulse duration, corresponding to a peak power of 50.7 kW for 10.4 W of incident pump power.

  20. Single-mode, All-Solid-State Nd:YAG Laser Pumped UV Converter

    NASA Technical Reports Server (NTRS)

    Prasad, Narasimha S.; Armstrong, Darrell, J.; Edwards, William C.; Singh, Upendra N.

    2008-01-01

    In this paper, the status of a high-energy, all solid-state Nd:YAG laser pumped nonlinear optics based UV converter development is discussed. The high-energy UV transmitter technology is being developed for ozone sensing applications from space based platforms using differential lidar technique. The goal is to generate greater than 200 mJ/pulse with 10-50 Hz PRF at wavelengths of 308 nm and 320 nm. A diode-pumped, all-solid-state and single longitudinal mode Nd:YAG laser designed to provide conductively cooled operation at 1064 nm has been built and tested. Currently, this pump laser provides an output pulse energy of >1 J/pulse at 50 Hz PRF and a pulsewidth of 22 ns with an electrical-to-optical system efficiency of greater than 7% and a M(sup 2) value of <2. The single frequency UV converter arrangement basically consists of an IR Optical Parametric Oscillator (OPO) and a Sum Frequency Generator (SFG) setups that are pumped by 532 nm wavelength obtained via Second Harmonic Generation (SHG). In this paper, the operation of an inter cavity SFG with CW laser seeding scheme generating 320 nm wavelength is presented. Efforts are underway to improve conversion efficiency of this mJ class UV converter by modifying the spatial beam profile of the pump laser.

  1. Cladding for transverse-pumped solid-state laser

    NASA Technical Reports Server (NTRS)

    Byer, Robert L. (Inventor); Fan, Tso Y. (Inventor)

    1989-01-01

    In a transverse pumped, solid state laser, a nonabsorptive cladding surrounds a gain medium. A single tranverse mode, namely the Transverse Electromagnetic (TEM) sub 00 mode, is provided. The TEM sub 00 model has a cross sectional diameter greater than a transverse dimension of the gain medium but less than a transverse dimension of the cladding. The required size of the gain medium is minimized while a threshold for laser output is lowered.

  2. Plasma Formation During Operation of a Diode Pumped Alkali Laser (DPAL) in Cs

    NASA Astrophysics Data System (ADS)

    Babaeva, Natalia Yu.; Zatsarinny, Oleg; Bartschat, Klaus; Kushner, Mark J.

    2014-10-01

    Diode pumped Alkali Lasers (DPALs) produce laser action on the resonant lines of alkali atoms. Diode lasers resonantly pump the 2P3/2 state of the alkali atom which is collisionally relaxed to the 2P3/2 state which then lases to the ground state 2S1/2. The low optical quality of high power semiconductor diode lasers is converted into high optical quality laser radiation from the alkali vapor. The Cs DPAL system using Ar/Cs/C2H6 mixtures has shown promising results. (C2H6 is the collisional relaxant.) In other studies, resonant excitation of alkali vapor by low power lasers has been used to produce highly ionized channels, initiated through associative ionization and superelastic electron heating. The issue then arises if plasma formation occurs during DPAL by similar mechanisms which would be detrimental to laser performance. In this paper, we report on results from a computational study of a DPAL using Cs vapor. The global model addresses quasi-cw pumping of the Cs(2P3/2) state by laser diodes, and includes a full accounting of the resulting electron kinetics. To enable this study, the B-spline R-matrix (BSR) with pseudostates method was employed to calculate electron impact cross sections for Cs. We found that for pump rates of many to 10 kW/cm2, plasma densities approaching 1013 cm-3 occur during laser oscillation with higher values in the absence of laser oscillation. Supported by DoD High Energy Laser Mult. Res. Initiative and NSF.

  3. Solar Pumped High Power Solid State Laser for Space Applications

    NASA Technical Reports Server (NTRS)

    Fork, Richard L.; Laycock, Rustin L.; Green, Jason J. A.; Walker, Wesley W.; Cole, Spencer T.; Frederick, Kevin B.; Phillips, Dane J.

    2004-01-01

    Highly coherent laser light provides a nearly optimal means of transmitting power in space. The simplest most direct means of converting sunlight to coherent laser light is a solar pumped laser oscillator. A key need for broadly useful space solar power is a robust solid state laser oscillator capable of operating efficiently in near Earth space at output powers in the multi hundred kilowatt range. The principal challenges in realizing such solar pumped laser oscillators are: (1) the need to remove heat from the solid state laser material without introducing unacceptable thermal shock, thermal lensing, or thermal stress induced birefringence to a degree that improves on current removal rates by several orders of magnitude and (2) to introduce sunlight at an effective concentration (kW/sq cm of laser cross sectional area) that is several orders of magnitude higher than currently available while tolerating a pointing error of the spacecraft of several degrees. We discuss strategies for addressing these challenges. The need to remove the high densities of heat, e.g., 30 kW/cu cm, while keeping the thermal shock, thermal lensing and thermal stress induced birefringence loss sufficiently low is addressed in terms of a novel use of diamond integrated with the laser material, such as Ti:sapphire in a manner such that the waste heat is removed from the laser medium in an axial direction and in the diamond in a radial direction. We discuss means for concentrating sunlight to an effective areal density of the order of 30 kW/sq cm. The method integrates conventional imaging optics, non-imaging optics and nonlinear optics. In effect we use a method that combines some of the methods of optical pumping solid state materials and optical fiber, but also address laser media having areas sufficiently large, e.g., 1 cm diameter to handle the multi-hundred kilowatt level powers needed for space solar power.

  4. Dynamic model of optically pumped energy storage lasers

    SciTech Connect

    Kelly, J.H.

    1980-01-01

    A dynamic, complete model of optically pumped, energy storage laser media has been developed. This model predicts stored energy density and heat deposition as a function of both time and space. The relevant physics for solid state and liquid energy storage media has been considered including non-radiative loss mechanisms such as cooperative relaxation and multiphonon relaxation, and radiation loss mechanisms such as spontaneous emission and, for one particular geometry, amplified spontaneous emission. The model was applied to two energy storage media: xenon flashlamp pumped neodymium in glass and resonantly pumped (either xeF or dye) trivalent thulium in glass. For the nonradiative losses in both Nd and Tm systems classical electromagnetic cooperative relaxation theory was used. A concentration squared dependence is predicted and a 3/2 power dependence observed. The linear dependence on concentration of an impurity having a high energy vibration predicted by multiphonon decay theory was observed for Nd in phosphate glasses. This is strong evidence for stimulated phonon emission. Measured zero-doping fluorescence lifetimes were used in the model. Measured zero-doping fluorescence lifetimes were used in the model. Comparisons of predictions with experiment are presented. Finally, the model was applied to a large aperture, active-mirror configuration Nd:glass amplifier. This necessitated including the effect of ASE on the inversion density. Because of the unique geometry of the active mirror amplifier ASE could be approximated as a parasitic oscillation which clamps the inversion at a specific level determined from small signal gain measurements. Comparisons with the measured small signal performance of several active mirrors is shown and agreement is excellent. Consequently, the model has become an on-line design tool for optimization of large aperture amplifiers.

  5. Optimized Biasing of Pump Laser Diodes in a Highly Reliable Metrology Source for Long-Duration Space Missions

    NASA Technical Reports Server (NTRS)

    Poberezhskiy, Ilya Y; Chang, Daniel H.; Erlig, Herman

    2011-01-01

    Optical metrology system reliability during a prolonged space mission is often limited by the reliability of pump laser diodes. We developed a metrology laser pump module architecture that meets NASA SIM Lite instrument optical power and reliability requirements by combining the outputs of multiple single-mode pump diodes in a low-loss, high port count fiber coupler. We describe Monte-Carlo simulations used to calculate the reliability of the laser pump module and introduce a combined laser farm aging parameter that serves as a load-sharing optimization metric. Employing these tools, we select pump module architecture, operating conditions, biasing approach and perform parameter sensitivity studies to investigate the robustness of the obtained solution.

  6. Directly diode-pumped femtosecond laser based on an Yb:KYW crystal

    NASA Astrophysics Data System (ADS)

    Kim, G. H.; Yang, J.; Lee, D. S.; Kulik, A. V.; Sall', E. G.; Chizhov, S. A.; Yashin, V. E.; Kang, U.

    2012-01-01

    Ultrashort pulse laser systems are widely used in many areas such as microprocessing of various materials, the generation of terahertz radiation, nonlinear optics, medical tomography, chemistry, and biology due to the high peak power and large spectral width. For a practical usage of the femtosecond lasers, they must be fairly compact and stable. These conditions are most fully met when laser media are used that allow direct pumping with the radiation from semiconductor injection lasers, which are more compact, reliable, and inexpensive than pumping with solid-state lasers. Since Ytterbium-doped crystals have a broad luminescence band for generating femtosecond pulses less than 500 fs wide, they are attractive as materials for lasers with direct diode pumping. Moreover, the position of the central luminescence wavelength of Yb:KGW and Yb:KYW crystals makes them promising priming sources of femtosecond pulses for amplifiers that operate at wavelengths close to 1 μm (Yb:KGW, Yb-glass, Nd-glass, Yb:YAG, etc.) We developed a femtosecond generator based on the Yb:KYW crystal with direct pumping by the radiation of a laser diode with fiber output of the pump radiation. The use of such pumping, as well as of chirped mirrors to compensate intracavity dispersion, made it possible to generate a continuous sequence of optical pulses 90 fs wide at a frequency of 87.8 MHz with a mean radiation power of more than 1 W. The product of the pulse width by the spectral width is close to the theoretical limit, and this indicates that there is no frequency modulation.

  7. Picosecond pumping of extreme-ultraviolet lasers using preformed laser plasmas

    NASA Astrophysics Data System (ADS)

    Yamakoshi, H.; Herman, P. R.; Le Flohic, M. P.; Xiao, B.; Zhao, L.; Kulcsar, G.; Budnik, F. W.; Marjoribanks, R. S.

    1996-02-01

    Weak laser prepulses were used for the first time with picosecond-duration laser light to enhance laser-target absorption for efficient excitation of extreme-ultraviolet lasers. A traveling-wave excitation geometry and a self-healing mercury-wetted target were used with 300-ps prepulses to pump the photoionization Xe III laser at 109-nm wavelength. Fully saturated laser gain was demonstrated for both 32-ps and 1.4-ps small-signal gain coefficients exceeded 2 cm -1 for on-target laser fluences of only 4 J / cm2.

  8. Investigations of laser pumped gas cell atomic frequency standard

    NASA Technical Reports Server (NTRS)

    Volk, C. H.; Camparo, J. C.; Fueholz, R. P.

    1982-01-01

    The performance characteristics of a rubidium gas cell atomic frequency standard might be improved by replacing the standard rubidium discharge lamp with a single mode laser diode. Aspects of the laser pumped gas cell atomic clock studied include effects due to laser intensity, laser detuning, and the choice of the particular atomic absorption line. Results indicate that the performance of the gas cell clock may be improved by judicious choice of the operating parameters of the laser diode. The laser diode also proved to be a valuable tool in investigating the operation of the conventional gas cell clock. Results concerning linewidths, the light shift effect and the effect of isotopic spin exchange in the conventional gas cell clock are reported.

  9. Single-frequency diode-pumped lasers for free-space optical communication

    NASA Technical Reports Server (NTRS)

    Kane, Thomas J.; Cheng, Emily A. P.; Gerstenberger, David C.; Wallace, Richard W.

    1990-01-01

    Recent advances in laser technology for intersatellite optical communication systems are reviewed and illustrated with graphs and diagrams. Topics addressed include (1) single-frequency diode-pumped Nd:YAG lasers of monolithic ring configuration (yielding 368-384 mW output power with 1-W pumping), (2) injection chaining of up to 10 monolithic resonators to achieve redundancy and/or higher output power, (3) 2-kHz-linewidth 5-mW versions of (1) which are tunable over a 30-MHz range for use as local oscillators in coherent communication, (4) resonant external modulation and doubling or resonant phase modulation of diode-pumped lasers, and (5) wavelength multiplexing.

  10. Random fiber laser of POSS solution-filled hollow optical fiber by end pumping

    NASA Astrophysics Data System (ADS)

    Hu, Zhijia; Zheng, Hongjun; Wang, Lijuan; Tian, Xiujie; Wang, Tongxin; Zhang, Qijin; Zou, Gang; Chen, Yang; Zhang, Qun

    2012-09-01

    Random fiber laser is obtained by end pumping a hollow optical fiber (HOF) filled with a dispersive solution of polyhedral oligomeric silsesquioxanes (POSS) nanoparticles and laser dye pyrromethene 597 (PM597) in carbon disulfide (CS2), in which the concentration is 1.5×10-2 M for PM597 and 18.5 wt% for POSS, respectively. It is found that the pump light at the one end of the liquid core optical fiber (LCOF) can pass the whole length of LCOF because the POSS nanoparticles were dispersed in CS2 at a molecular level (1-3 nm) with high stability and without sedimentation. Above the threshold pump energy (˜0.81 mJ) the random fiber laser appears coherent and resonant feedback multimode lasing in the weakly scattering system. For the LCOF containing PM597 with the same concentration and no POSS nanoparticles, there occurs only ASE that can be observed under the same experimental condition.

  11. Rapid prototyping of a micro pump with laser micromaching

    SciTech Connect

    Wong, C.C.; Chu, D.; Liu, S.L.; Tuck, M.R.; Mahmud, Z.; Amatucci, V.

    1995-08-01

    A micro electrohydrodynamic (EHD) injection pump has been developed using laser micromaching technology. Two designs have been fabricated, tested, and evaluated. The first design has two silicon pieces with KOH-etched wells which are stacked on the top of each other. The wells am etched on one side of the wafer and gold is deposited on the other side to serve as the pump electrodes. A ND:YAG laser is used to drill an array holes in the well region of both silicon die. This creates a grid distribution with a rectangular pattern. Next the well regions of the die are aligned, and the parts are bonded together using a Staystik thermoplastic. The pump unit is then mounted into a ceramic package over the hole drilled to permit fluid flow. Aluminum ribbon wire bonds are used to connect the pump electrodes to the package leads. Isolation of metallization and wires is achieved by filling the package well and coating the wires with polyimide.When a voltage is applied at the electrodes, ions are injected into the working fluid, such as an organic solvent, thus inducing flow. The second design has the die oriented ``back-to-back`` and bonded together with stayform. A ``back-to-back`` design will decrease the grid distance so that a smaller voltage is required for pumping. Preliminary results have demonstrated that this micro pump can achieved a pressure head of about 287 Pa with an applied voltage of 120 volts.

  12. Anomalous dispersion and the pumping of far infrared (FIR) lasers

    NASA Technical Reports Server (NTRS)

    Lawandy, N. M.

    1978-01-01

    It is shown that the anomalous dispersion at the pump transition in molecular far-infrared lasers (FIR) can lead to sizable focusing and defocusing effects. Criteria for beam spreading and trapping are considered with CH2F as an example.

  13. Design of a tunable parametric wavelength conversion system between 2 and 3 μm pumped by a high-average-power Yb:YAG thin-disk laser

    NASA Astrophysics Data System (ADS)

    Novák, Ondřej; Miura, Taisuke; Severová, Patricie; Endo, Akira; Mocek, Tomáš

    2013-05-01

    With increasing energy densities of laser pulses the laser induced damage threshold (LIDT) testing becomes an important characterization of optical components. The emission wavelength of several laser materials is in the 2 - 3 μm wavelength-range. We propose a wavelength conversion system generating tunable sub-ns pulses for LIDT measurements in this IR spectral range. The pump beam of the conversion system will be based on the thin-disk laser technology. The Yb-fiber-laser seeded CPA system with high-energy Yb:YAG thin-disk regenerative amplifier will produce uncompressed pulses of 0.5 ns width, 130 mJ energy, at wavelength of 1030 nm with 1 kHz repetition rate giving 130 W of average power. Output of the thin-disk regenerative amplifier will pump an optical parametric generator (OPG) and subsequent optical parametric amplifiers (OPA). The tunable output wavelength of the OPG will be between 1.5 μm - 2.1 μm for the signal beam and between 2.1 μm - 3 μm for the idler beam. The signal will be amplified in the OPAs because the optics and diagnostics is more easily available below 2 μm wavelength. The tunable multi-millijoule source above 2.1 μm will be the idler beam taken from the last amplification stage. High-average output power of 10 W at 1 kHz repetition rate will be unique among 2 - 3 μm tunable systems. Operation of the amplifiers at high-intensities and high-average powers limits the system performance. The thermal load of crystals caused by the partial beam absorption will be studied. Further, the damage threshold of optical components, transmission range of nonlinear crystals, and amplifiers bandwidths will be addressed.

  14. Resonantly pumped high efficiency Ho:YAG laser.

    PubMed

    Shen, Ying-Jie; Yao, Bao-Quan; Duan, Xiao-Ming; Dai, Tong-Yu; Ju, You-Lun; Wang, Yue-Zhu

    2012-11-20

    High-efficient CW and Q-switched Ho:YAG lasers resonantly dual-end-pumped by two diode-pumped Tm:YLF lasers at 1908 nm were investigated. A maximum slope efficiency of 74.8% in CW operation as well as a maximum output power of 58.7 W at 83.2 W incident pump power was achieved, which corresponded to an optical-to-optical conversion efficiency of 70.6%. The maximum pulse energy of 2.94 mJ was achieved, with a 31 ns FWHM pulse width and a peak power of approximately 94.7 kW. PMID:23207298

  15. Research on fission induced plasmas and nuclear pumped lasers at the Los Alamos Scientific Laboratory

    NASA Technical Reports Server (NTRS)

    Helmick, H. H.

    1979-01-01

    A program of research on gaseous uranium and uranium plasmas is being conducted at The Los Alamos Scientific Laboratory under sponsorship of the National Aeronautics and Space Administration. The objective of this work is twofold: (1) to demonstrate the proof of principle of a gaseous uranium fueled reactor, and (2) pursue fundamental research on nuclear pumped lasers. The relevancy of the two parallel programs is embodied in the possibility of a high-performance uranium plasma reactor being used as the power supply for a nuclear pumped laser system. The accomplishments in the two above fields are summarized

  16. Activation of the Mercury Laser: A Diode-Pumped Solid-State Laser Driver for Inertial Fusion

    SciTech Connect

    Bayramian, A J; Bibeau, C; Beach, R J; Chanteloup, J C; Ebbers, C A; Kanz, K; Nakano, H; Payne, S A; Powell, H T; Schaffers, K I; Seppala, L; Skulina, K; Smith, L K; Sutton, S B; Zapata, L E

    2001-03-07

    Initial measurements are reported for the Mercury laser system, a scalable driver for rep-rated high energy density physics research. The performance goals include 10% electrical efficiency at 10 Hz and 100 J with a 2-10 ns pulse length. This laser is an angularly multiplexed 4-pass gas-cooled amplifier system based on image relaying to minimize wavefront distortion and optical damage risk at the 10 Hz operating point. The efficiency requirements are fulfilled using diode laser pumping of ytterbium doped strontium fluorapatite crystals.

  17. A scalable high-energy diode-pumped solid state laser for laser-plasma interaction science and applications

    NASA Astrophysics Data System (ADS)

    De Vido, M.; Ertel, K.; Mason, P. D.; Banerjee, S.; Phillips, P. J.; Butcher, T. J.; Smith, J. M.; Shaikh, W.; Hernandez-Gomes, C.; Greenhalgh, R. J. S.; Collier, J. L.

    2016-05-01

    Laser systems efficiently generating nanosecond pules at kJ energy levels and at multi-Hz repetition rates are required in order to translate laser-plasma interactions into practical applications. We have developed a scalable, actively-cooled diode-pumped solid state laser amplifier design based on a multi-slab ceramic Yb:YAG architecture called DiPOLE (Diode-Pumped Optical Laser for Experiments) capable of meeting such requirements. We demonstrated 10.8 J, 10 Hz operation at 1030 nm using a scaled-down prototype, reaching an optical-to-optical efficiency of 22.5%. Preliminary results from a larger scale version, delivering 100 J pulse energy at 10 Hz, are also presented.

  18. High power laser apparatus and system

    NASA Technical Reports Server (NTRS)

    Evans, J. C., Jr.; Brandhorst, H. W., Jr. (Inventor)

    1975-01-01

    A high-power, continuous-wave laser was designed for use in power transmission and energy-collecting systems, and for producing incoherent light for pumping a laser material. The laser has a high repetitive pulsing rate per unit time, resulting in a high-power density beam. The laser is composed of xenon flash tubes powered by fast-charging capacitors flashed in succession by a high-speed motor connected to an automobile-type distributor.

  19. Laser diode pumped 1μ Nd;YAG and Nd:BEL lasers

    NASA Astrophysics Data System (ADS)

    Scheps, R.; Poirier, P.; Myers, J. F.; Heller, D. F.

    1989-10-01

    Peformance data for laser diode-pumped cw Nd:YAG and Nd:BEL lasers are presented. Two single stripe laser diodes are used as the pump source, each emitting 1 W in the pump band. The heat sink for the lasers is temperature controlled to allow for wavelength tunability. The resonator is based on a hemispherical design. Output and pump threshold measurements were made and gain and loss for Nd in both hosts were measured. The output power from the Nd:YAG rod was in excess of 870 mW with a slope efficiency of 58% and an overall electrical efficiency of 13%. In Nd:BEL, the output power was in excess of 635 mW with a slope efficiency of 49% and an electrical efficiency of 9.5%.

  20. Metal hydride heat pump system

    SciTech Connect

    Nishizaki, T.; Miyamoto, K.; Miyamoto, M.; Nakata, Y.; Yamaji, K.; Yoshida, K.

    1985-06-18

    A metal hydride heat pump system has a plurality of operating units, the metal hydride heat exchange medium of each operating unit be a combination of a first metal hydride having a lower equilibrium dissociation pressure at the operating temperature and a second metal hydride having a higher equilibrium dissociation pressure at the opening temperature and the metal hydrides being such that hydrogen can flow freely between the two metal hydrides, wherein the equilibrium dissociation pressure characteristics of one or both of the first and second metal hydrides in a given operating unit differ from those of one or both of the first and second metal hydrides in at least one other operating unit.

  1. Laser diode pumped high efficiency Yb:YAG crystalline fiber waveguide lasers

    NASA Astrophysics Data System (ADS)

    Mu, Xiaodong; Meissner, Stephanie; Meissner, Helmuth

    2015-02-01

    Single-clad and double-clad Yb:YAG crystalline fiber waveguides (CFWs) have been prepared with Adhesive-Free Bonding (AFB®) technology. By using a fiber coupled laser diode as pump source, a single-mode laser with near diffraction limited beam quality M2=1.02 has been demonstrated in a double-clad CFW. The laser output power and efficiency are 13.2 W and 34%, respectively. In a single-clad CFW, core pumping was used. The laser output has top-hat beam profile. An output power of 28 W and a slope efficiency of 78% have been achieved respectively.

  2. Traveling-wave laser-produced-plasma energy source for photoionization laser pumping and lasers incorporating said

    DOEpatents

    Sher, Mark H.; Macklin, John J.; Harris, Stephen E.

    1989-09-26

    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.

  3. Ray tracing in nuclear-pumped flowing gas lasers

    SciTech Connect

    Mat'ev, V Yu

    2003-06-30

    The ray tracing in the resonators of a nuclear-pumped flowing gas lasers is considered. The refractive index profile of the medium in a direction perpendicular to the optical axis in such lasers can be considered parabolic, but the steepness of the parabola is quite nonuniform along the ray trace, and the resonator stability condition (the absolute value of the ray matrix trace for a single trip of the ray in the resonator is smaller than two) is not sufficient to confine the ray within the resonator after a large number of trips. (lasers)

  4. A 170 J electron beam pumped XeF(C{r_arrow}A) laser

    SciTech Connect

    Litzenberger, L.N.; Smith, M.J.

    1995-03-01

    A pulse output energy of 170 J has been achieved from an XeF (C{r_arrow}A) laser system, pumped by a pair of counterpropagating, three-meter-long electron beams. This represents a record for all types of pumping, for this excimer system. Energy was extracted from a volume of {approximately}100 L, using a free-running stable oscillator. No evidence of laser oscillations on the competing XeF(B{r_arrow}X) transition was observed. Within the extraction volume the laser gas was pumped at a rate of 140 kW/cm{sup 3} (time average value), for a period of 1.7 {mu}s. The optical cavity was folded, giving a gain length of 6 m. The optical pulse duration was 0.8 {mu}s (full width at half maximum), and the observed flux buildup time of {approximately}1 {mu}s was consistent with modeling and a measurement of the net gain. The specific output energy was 1.7 J/L which is comparable to that achieved in previous, small scale experiments at somewhat higher pump rate. The results confirm the volumetric scalability of the electron beam pumped XeF(C{r_arrow}A) laser system to high output energy per pulse, and the feasibility of operating this system at a low electron beam pump rate which relaxes constraints on the design of the electron gun and pulse power subsystems in a high output energy device. Means for extending the laser pulse duration and increasing the output energy of the specific test device are discussed. An output energy of {approximately}1,000 J is projected for an optimized gas cell width, for full size resonator mirrors, and with injection.

  5. Lamp pumped Nd:YAG laser. Space-qualifiable Nd:YAG laser for optical communications

    NASA Technical Reports Server (NTRS)

    Ward, K. B.

    1973-01-01

    Results are given of a program concerned with the design, fabrication, and evaluation of alkali pump lamps for eventual use in a space qualified Nd:YAG laser system. The study included evaluation of 2mm through 6mm bore devices. Primary emphasis was placed upon the optimization of the 4mm bore lamp and later on the 6mm bore lamp. As part of this effort, reference was made to the Sylvania work concerned with the theoretical modeling of the Nd:YAG laser. With the knowledge gained, a projection of laser performance was made based upon realistic lamp parameters which should easily be achieved during following developmental efforts. Measurements were made on the lamp performance both in and out of the cavity configuration. One significant observation was that for a constant vapor pressure device, the spectral and fluorescent output did not vary for vacuum or argon environment. Therefore, the laser can be operated in an inert environment (eg. argon) with no degradation in output. Laser output of 3.26 watts at 430 watts input was obtained for an optimized 4mm bore lamp.

  6. Reciprocating Pump Systems for Space Propulsion

    SciTech Connect

    Whitehead, J C

    2004-06-10

    Small propellant pumps can reduce rocket hardware mass, while increasing chamber pressure to improve specific impulse. The maneuvering requirements for planetary ascent require an emphasis on mass, while those of orbiting spacecraft indicate that I{sub SP} should be prioritized during pump system development. Experimental efforts include initial testing with prototype lightweight components while raising pump efficiency to improve system I{sub SP}.

  7. Solid-state laser-pumped high-power electric-discharge HF laser

    SciTech Connect

    Velikanov, S D; Garanin, Sergey G; Kodola, B E; Komarov, Yu N; Shchurov, V V; Efanov, V M; Efanov, M V; Yarin, P M; Kazantsev, S Yu; Kononov, I G; Firsov, K N; Domazhirov, A P; Podlesnykh, S V; Sivachev, A A

    2010-08-03

    We report the possibility of creating high-power nonchain electric-discharge HF lasers with an all-solid-state pump source. The maximum energy stored in the pump source capacitors based on solid-state FID-switches is 990 J for the open-circuit voltage of 240 kV. The pulse energy of 30 J is obtained in the hydrogen-containing SF{sub 6} mixture at the electric efficiency of the order of 3%. (lasers)

  8. Bismuth doped fiber laser and study of unsaturable loss and pump induced absorption in laser performance.

    PubMed

    Kalita, Mridu P; Yoo, Seongwoo; Sahu, Jayanta

    2008-12-01

    A short Bi doped fiber laser operating in the wavelength region of 1160-1179 nm has been demonstrated. The influence of unsaturable loss on laser performance is investigated. Excited state absorption in Bi doped germano-alumino silicate fiber is reported in the 900-1300 nm wavelength range under 800 and 1047 nm pumping. Bi luminescence and fluorescence decay properties under different pumping wavelengths are also investigated. PMID:19065243

  9. Electron beam method and apparatus for obtaining uniform discharges in electrically pumped gas lasers

    DOEpatents

    Fenstermacher, Charles A.; Boyer, Keith

    1986-01-01

    A method and apparatus for obtaining uniform, high-energy, large-volume electrical discharges in the lasing medium of a gas laser whereby a high-energy electron beam is used as an external ionization source to ionize substantially the entire volume of the lasing medium which is then readily pumped by means of an applied potential less than the breakdown voltage of the medium. The method and apparatus are particularly useful in CO.sub.2 laser systems.

  10. Injection chaining of diode-pumped single-frequency ring lasers for free-space communication

    NASA Technical Reports Server (NTRS)

    Cheng, E. A. P.; Kane, T. J.; Wallace, R. W.; Cornwell, D. M., Jr.

    1991-01-01

    A high-power three-stage laser suitable for use in a space communication system has been built. This laser uses three diode-pumped Nd:YAG oscillators coherently combined using the technique of injection chaining. All three oscillators are in one compact and permanently aligned package, and are actively frequency locked to provide CW single frequency output. The three stages provide the redundancy desirable for space communications.

  11. Perfluoro-n-hexyl iodide as gain media for high power, continuous solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Tabibi, Bagher M.; Humes, Donald H.; Weaver, Willard R.

    1990-01-01

    A comparative study of CW laser performance with n-C6F13I and n-C3F7I was performed using a 10-W solar-simulator-pumped laser system. The measured output power for n-C6F13I is near 10 W and is comparable to that of n-C3F7I. However, n-C6F13I has the advantages of easy purification and repeated use.

  12. Efficient 750-nm LED-pumped Nd:YAG laser.

    PubMed

    Huang, Kuan-Yan; Su, Cheng-Kuo; Lin, Meng-Wei; Chiu, Yu-Chung; Huang, Yen-Chieh

    2016-05-30

    We report an Nd:YAG laser pumped by light emission diodes (LEDs) at 750 nm. With 1% output coupling from a linear cavity containing a 2-cm long Nd:YAG crystal, the laser generated 37.5 μJ pulse energy at 1064 nm with M2 = 1.1 when pumped by 2.73-mJ LED energy in a 1-ms pulse at a 10 Hz rate. The measured optical and slope efficiencies for this linear-cavity laser are 1.36, and 9%, respectively. With 1 and 5% output couplings from a Z-cavity containing the same laser crystal, the lasers generated 346 and 288 μJ pulse energy with an optical efficiency of 3.4 and 2.8% and slope efficiency of 6.6 and 14%, respectively, for the same 1-ms pump pulse repeating at a 10 Hz rate. At the highest output from the Z-cavity, the measured M2 for the beam is 3.6. PMID:27410125

  13. Highly efficient solar-pumped Nd:YAG laser.

    PubMed

    Liang, Dawei; Almeida, Joana

    2011-12-19

    The recent progress in solar-pumped laser with Fresnel lens and Cr:Nd:YAG ceramic medium has revitalized solar laser researches, revealing a promising future for renewable reduction of magnesium from magnesium oxide. Here we show a big advance in solar laser collection efficiency by utilizing an economical Fresnel lens and a most widely used Nd:YAG single-crystal rod. The incoming solar radiation from the sun is focused by a 0.9 m diameter Fresnel lens. A dielectric totally internally reflecting secondary concentrator is employed to couple the concentrated solar radiation from the focal zone to a 4 mm diameter Nd:YAG rod within a conical pumping cavity. 12.3 W cw laser power is produced, corresponding to 19.3 W/m(2) collection efficiency, which is 2.9 times larger than the previous results with Nd:YAG single-crystal medium. Record-high slope efficiency of 3.9% is also registered. Laser beam quality is considerably improved by pumping a 3 mm diameter Nd:YAG rod. PMID:22274224

  14. ND laser with co-doped ion(s) pumped by visible laser diodes

    NASA Astrophysics Data System (ADS)

    Scheps, Richard

    1993-04-01

    The 1.06 microns Nd transition in a co-doped Cr,Nd:Gd3Sc2Ga3O12 (Cr,Nd:GSGG) gain element is obtained by diode pumping Cr(3+) at 670 run and produces efficient, low threshold laser operation. Although co-doped Cr,Nd:GSGG was developed for more efficient flashlamp pumping, it has the desirable property of having an extraordinarily broad absorption to allow for efficient diode pumping relative to the ND:YAG laser. The consequent broad bandwidth tolerance of the Cr,Nd:GSGG for the diode pumping radiation allows diode pumping of the 1.06 microns transition without regard to the wavelength of the visible diodes which has the potential for reducing the cost of the semiconductor pump and also demonstrates the extended versatility of these diodes which previously had been restricted to pump the Cr(3+) tunable vibronic lasers. CW and long pulse diode pumping provided pump power levels as high as 300 mW CW and 1 W pulsed. The lowest threshold power was measured at 938 micron W and the highest output power was obtained at 43 mW CW and 173 mW pulsed. The best slope efficiency obtained was 42.1%, 78% of the theoretical maximum. Loss measurements indicate a value of 0.4%/cm.

  15. Bistable direction switching in an off-axis pumped continuous wave ruby laser

    NASA Technical Reports Server (NTRS)

    Afzal, R. Sohrab; Lawandy, N. M.

    1988-01-01

    A report is presented of the observation of hysteretic bistable direction switching in a single-mode CW ruby laser system. This effect is only observed when the pump beam which is focused into the ruby rod is misaligned with respect to the rod end faces. At low pump powers, the ruby lases in a mode nearly collinear with the pump axis. At a higher pump power the ruby switches to a mode that is collinear with the rod end faces and preserves the original polarization. The effect is large enough to switch the beam by an angle equal to twice the diffraction angle. The observations show that under steady-state pumping, a CW ruby laser can exhibit bistable operation in its output direction and power. A calculation using the heat equation with two concentric cylinders with one as a heat source (pump laser) and the outer wall of the other held at 77 K, gives an increase in core temperature of about 0.01 K. Therefore, the increase in temperature is not large enough to change the index of refraction to account for such large macroscopic effects.

  16. Research on High-Intensity Picosecond Pump Laser in Short Pulse Optical Parametric Amplification

    NASA Astrophysics Data System (ADS)

    Pan, Xue; Peng, Yu-Jie; Wang, Jiang-Feng; Lu, Xing-Hua; Ouyang, Xiao-Ping; Chen, Jia-Lin; Jiang, You-En; Fan, Wei; Li, Xue-Chun

    2013-01-01

    A 527 nm pump laser generating 1.7 mJ energy with peak power of more than 0.12 GW is demonstrated. The theoretical simulation result shows that it has 106 gain in the picosecond-pump optical parametric chirped pulse amplification when the pump laser peak power is 0.1 GW and the intensity is more than 5 GW/cm2, and that it can limit the parametric fluorescence in the picosecond time scale of pump duration. The pump laser system adopts a master-oscillator power amplifier, which integrates a more than 30 pJ fiber-based oscillator with a 150 μJ regenerative amplifier and a relay-imaged four-pass diode-pump Nd glass amplifier to generate a 1 Hz top hat spatial beam and about 14 ps temporal Guassian pulse with <2% pulse-to-pulse energy stability. The output energy of the power amplifier is limited to 4 mJ for B-integral concern, and the frequency doubling efficiency can reach 65% with input intensity 10 GW/cm2.

  17. Parameters of a dye laser with transverse pumping

    SciTech Connect

    Burakov, V.S.; Samson, A.M.; Zhukovskii, V.V.; Isaevich, A.V.

    1987-12-01

    The authors describe a new method for determining the excitation and output parameters of dye laser media under conditions of transverse optical pumping by laser radiation. The dye is modeled as a medium with two electron-vibrational levels. The method is based on the variation of the value of the distance on the mirror reflection coefficients of the resonator and on estimates of inactive or parasitic losses, the probability of exciting active dye molecules with the radiation incident on the front face of the cell, and the unsaturated gain coefficient of that output frequency. Experimental data are then derived for these conditions for a rhodamine 4C solution in ethanol. Pumping was done using a neodymium laser.

  18. A nuclear pumped laser for the Laboratory Microfusion Facility

    NASA Astrophysics Data System (ADS)

    Miley, G. H.

    1989-08-01

    The Laboratory Microfusion Facility (LMF) has been proposed to study Inertial Confinement Fusion targets with reactor-grade gains. An advanced solid-state laser is the prime candidate as the driver for the LMF. However, here, a conceptual design is presented here for an alternate approach using a Nuclear Pumped Laser (NPL). A pulsed fission reactor is used to excite an oxygen-iodine laser in this design, based on preliminary data on nuclear pumping of O2(1-Delta). Although a working NPL of this specific type has not yet been assembled, it is believed that this concept holds great potential, both as a test facility driver and as a future power reactor.

  19. Coherent communication link using diode-pumped lasers

    NASA Technical Reports Server (NTRS)

    Kane, Thomas J.; Wallace, Richard W.

    1989-01-01

    Work toward developing a diffraction limited, single frequency, modulated transmitter suitable for coherent optical communication or direct detection communication is discussed. Diode pumped, monolithic Nd:YAG nonplanar ring oscillators were used as the carrier beam. An external modulation technique which can handle high optical powers, has moderate modulation voltage, and which can reach modulation rates of 1 GHz was invented. Semiconductor laser pumped solid-state lasers which have high output power (0.5 Watt) and which oscillate at a single frequency, in a diffraction limited beam, at the wavelength of 1.06 microns were built. A technique for phase modulating the laser output by 180 degrees with a 40-volt peak to peak driving voltage is demonstrated. This technique can be adapted for amplitude modulation of 100 percent with the same voltage. This technique makes use of a resonant bulk modulator, so it does not have the power handling limitations of guided wave modulators.

  20. Electrically pumped edge-emitting photonic bandgap semiconductor laser

    DOEpatents

    Lin, Shawn-Yu; Zubrzycki, Walter J.

    2004-01-06

    A highly efficient, electrically pumped edge-emitting semiconductor laser based on a one- or two-dimensional photonic bandgap (PBG) structure is described. The laser optical cavity is formed using a pair of PBG mirrors operating in the photonic band gap regime. Transverse confinement is achieved by surrounding an active semiconductor layer of high refractive index with lower-index cladding layers. The cladding layers can be electrically insulating in the passive PBG mirror and waveguide regions with a small conducting aperture for efficient channeling of the injection pump current into the active region. The active layer can comprise a quantum well structure. The quantum well structure can be relaxed in the passive regions to provide efficient extraction of laser light from the active region.

  1. Heterodyne laser diagnostic system

    DOEpatents

    Globig, Michael A.; Johnson, Michael A.; Wyeth, Richard W.

    1990-01-01

    The heterodyne laser diagnostic system includes, in one embodiment, an average power pulsed laser optical spectrum analyzer for determining the average power of the pulsed laser. In another embodiment, the system includes a pulsed laser instantaneous optical frequency measurement for determining the instantaneous optical frequency of the pulsed laser.

  2. A High Efficiency Grazing Incidence Pumped X-ray Laser

    SciTech Connect

    Dunn, J; Keenan, R; Price, D F; Patel, P K; Smith, R F; Shlyaptsev, V N

    2006-08-31

    The main objective of the project is to demonstrate a proof-of-principle, new type of high efficiency, short wavelength x-ray laser source that will operate at unprecedented high repetition rates (10Hz) that could be scaled to 1kHz or higher. The development of a high average power, tabletop x-ray laser would serve to complement the wavelength range of 3rd and future 4th generation light sources, e.g. the LCLS, being developed by DOE-Basic Energy Sciences. The latter are large, expensive, central, synchrotron-based facilities while the tabletop x-ray laser is compact, high-power laser-driven, and relatively inexpensive. The demonstration of such a unique, ultra-fast source would allow us to attract funding from DOE-BES, NSF and other agencies to pursue probing of diverse materials undergoing ultrafast changes. Secondly, this capability would have a profound impact on the semiconductor industry since a coherent x-ray laser source would be ideal for ''at wavelength'' {approx}13 nm metrology and microscopy of optics and masks used in EUV lithography. The project has major technical challenges. We will perform grazing-incidence pumped laser-plasma experiments in flat or groove targets which are required to improve the pumping efficiency by ten times. Plasma density characterization using our existing unique picosecond x-ray laser interferometry of laser-irradiated targets is necessary. Simulations of optical laser propagation as well as x-ray laser production and propagation through freely expanding and confined plasma geometries are essential. The research would be conducted using the Physics Directorate Callisto and COMET high power lasers. At the end of the project, we expect to have a high-efficiency x-ray laser scheme operating below 20 nm at 10Hz with a pulse duration of {approx}2 ps. This will represent the state-of-the-art in x-ray lasers and would be a major step forward from our present picosecond laser-driven x-ray lasers. There is an added bonus of creating

  3. Application of principles of nonimaging optics to the construction of solid state laser pump cavities

    NASA Astrophysics Data System (ADS)

    Janevski, Zoran; Pantelic, Dejan V.

    1990-07-01

    In laser systems where it is impossible or impractical to use lamps and rod whose effective perimeters are matched, some elements of construction of cavities using nonimaging optical concentrators can be used to achieve improved designs in regard to efficiency and pumping uniformity.

  4. Laser satellite power systems - Concepts and issues

    NASA Astrophysics Data System (ADS)

    Walbridge, E. W.

    A laser satellite power system (SPS) converts solar power captured by Earth-orbiting satellites into electrical power on the Earth's surface, the satellite-to-ground transmission of power being effected by a laser beam. The laser SPS is an alternative to the microwave SPS. Lasers and how they work are described, as are the types of lasers - electric discharge, direct and indirect solar pumped, free electron, and closed-cycle chemical - that are candidates for application in a laser SPS. The advantages of a laser SPS over the microwave alternative are pointed out. One such advantage is that, for the same power delivered to the utility busbar, land requirements for a laser system are much smaller (by a factor of 21) than those for a microwave system. The four laser SPS concepts that have been presented in the literature are described and commented on. Finally key issues for further laser SPS research are discussed.

  5. New diode wavelengths for pumping solid-state lasers

    SciTech Connect

    Skidmore, J.A.; Emanuel, M.A.; Beach, R.J.

    1995-01-01

    High-power laser-diode arrays have been demonstrated to be viable pump sources for solid-state lasers. The diode bars (fill factor of 0.7) were bonded to silicon microchannel heatsinks for high-average-power operation. Over 12 W of CW output power was achieved from a one cm AlGaInP tensile-strained single-quantum-well laser diode bar. At 690 nm, a compressively-strained single-quantum-well laser-diode array produced 360 W/cm{sup 2} per emitting aperture under CW operation, and 2.85 kW of pulsed power from a 3.8 cm{sup 2} emitting-aperture array. InGaAs strained single-quantum-well laser diodes emitting at 900 nm produced 2.8 kW pulsed power from a 4.4 cm{sup 2} emitting-aperture array.

  6. Diode-Pumped Dye Laser Using a Tapered Optical Fiber

    NASA Astrophysics Data System (ADS)

    Patterson, Brian; Stofel, James; Myers, Elliot; Knize, Randy

    2015-05-01

    We describe the construction of a simple dye laser based on a single-mode optical fiber. Light from a 120-mW laser diode (λ = 520 nm) is launched into the fiber. The fiber is tapered to a diameter of approximately 1 μm and placed in Rhodamine 6G laser dye. The pump light interacts with the gain medium through the evanescent field outside the fiber causing stimulated emission, which couples back into the fiber. Mirrors on each end of the fiber provide the necessary feedback for lasing, and a grating is used to narrow the spectral output. We characterize the lasing threshold and output spectrum of the laser. This has been a good project for undergraduate students to learn about lasers and optics.

  7. Computing Temperatures In Optically Pumped Laser Rods

    NASA Technical Reports Server (NTRS)

    Farrukh, Usamah O.

    1991-01-01

    Computer program presents new model solving temperature-distribution problem for laser rods of finite length and calculates both radial and axial components of temperature distributions in these rods. Contains several self-checking schemes to prevent over-writing of memory blocks and to provide simple tracing of information in case of trouble. Written in Microsoft FORTRAN 77.

  8. Expansion cooled CO nuclear pumped laser

    NASA Technical Reports Server (NTRS)

    Davis, J. F.; Bird, P. F.; Mansfield, C. R.; Helmick, H. H.

    1979-01-01

    The paper describes a series of experiments designed to investigate the performance of a fission fragment excited CO laser with gasdynamic cooling. The experiments use a wall source of fission fragments to provide excitation of CO or CO gas mixtures. A separate investigation examines the effects on vibrational excitation distribution of CO or CO gas mixtures with the addition of UF6.

  9. Powerful 2-μm all-fiber laser sources pumped by Raman fiber lasers

    NASA Astrophysics Data System (ADS)

    Wang, Xiong; Zhou, Pu; Zhang, Hanwei; Jin, Xiaoxi; Wang, Xiaolin; Xiao, Hu; Liu, Zejin

    2014-11-01

    We present novel and powerful pump schemes for fiber laser sources operating near 2 μm, which employing high power Raman fiber lasers (RFLs) to provide sufficient pump light. Firstly, we demonstrate a Tm-doped fiber laser (TDFL) pumped by two RFLs at 1173 nm. The output power of the TDFL reached 96 W with slope efficiency of 0.42, and the central wavelength located at 1943.3 nm. This is the first TDFL with 100 W-level output power pumped by RFLs around Tm3+ ions' ~1200 nm absorption band. Secondly, we demonstrate a Ho-doped fiber laser (HDFL) employing a 1150 nm RFL as pump source. The 1150 nm RFL provided 110 W pump power and the output power of the HDFL reached 42 W with slope efficiency of 0.37. The lasing wavelength covered from 2046.8 nm to 2049.5 nm with optical signal-to-noise ratio more than 30 dB. This is the first HDFL pumped by a 1150 nm RFL and the highest output power achieved at this pump band. In the last, we present a high power Ho-doped fiber (HDF) superfluorescent source (SS) pumped by a 1150 nm RFL. The SS's output power reached 1.5 W, and the full width at half maximum was about 30 nm. This is the highest output power achieved in HDF as far as we know. The results above indicate promising and powerful pump schemes to achieve higher power output in fiber lasers near 2 μm, which also can be further improved by optimizing the parameters of the sources.

  10. Geothermal down well pumping system

    NASA Technical Reports Server (NTRS)

    Matthews, H. B.; Mcbee, W. D.

    1974-01-01

    A key technical problem in the exploitation of hot water geothermal energy resources is down-well pumping to inhibit mineral precipitation, improve thermal efficiency, and enhance flow. A novel approach to this problem involves the use of a small fraction of the thermal energy of the well water to boil and super-heat a clean feedwater flow in a down-hole exchanger adjacent to the pump. This steam powers a high-speed turbine-driven pump. The exhaust steam is brought to the surface through an exhaust pipe, condensed, and recirculated. A small fraction of the high-pressure clean feedwater is diverted to lubricate the turbine pump bearings and prevent leakage of brine into the turbine-pump unit. A project demonstrating the feasibility of this approach by means of both laboratory and down-well tests is discussed.

  11. Replacement Saltwell Pumping System Document Bibliography

    SciTech Connect

    BELLOMY, J.R.

    2000-12-07

    This document bibliography is prepared to identify engineering documentation developed during the design of the Replacement Saltwell Pumping System. The bibliography includes all engineering supporting documents and correspondence prepared prior to the deployment of the system in the field. All documents referenced are available electronically through the Records Management Information System (RMIS). Major components of the Replacement Saltwell Pumping System include the Sundyne Canned Motor Pump, the Water Filter Skid, the Injection Water Skid and the Backflow Preventer Assembly. Drawing H-14-104498 provides an index of drawings (fabrication details, P&IDs, etc.) prepared to support development of the Replacement Saltwell Pumping System. Specific information pertaining to new equipment can be found in Certified Vendor Information (CVI) File 50124. This CVI file has been established specifically for new equipment associated with the Replacement Saltwell Pumping System.

  12. Fibre-coupled red diode-pumped Alexandrite TEM00 laser with single and double-pass end-pumping

    NASA Astrophysics Data System (ADS)

    Arbabzadah, E. A.; Damzen, M. J.

    2016-06-01

    We report the investigation of an Alexandrite laser end-pumped by a fibre-coupled red diode laser module. Power, efficiency, spatial, spectral, and wavelength tuning performance are studied as a function of pump and laser cavity parameters. It is the first demonstration, to our knowledge, of greater than 1 W power and also highest laser slope efficiency (44.2%) in a diode-pumped Alexandrite laser with diffraction-limited TEM00 mode operation. Spatial quality was excellent with beam propagation parameter M 2 ~ 1.05. Wavelength tuning from 737–796 nm was demonstrated using an intracavity birefringent tuning filter. Using a novel double pass end-pumping scheme to get efficient absorption of both polarisation states of the scrambled fibre-delivered diode pump, a total output coupled power of 1.66 W is produced in TEM00 mode with 40% slope efficiency.

  13. Short-pulse Laser Capability on the Mercury Laser System

    SciTech Connect

    Ebbers, C; Armstrong, P; Bayramian, A; Barty, C J; Bibeau, C; Britten, J; Caird, J; Campbell, R; Chai, B; Crane, J; Cross, R; Erlandson, A; Fei, Y; Freitas, B; Jovanovic, I; Liao, Z; Molander, B; Schaffers, K; Stuart, B; Sutton, S; Ladran, T; Telford, S; Thelin, P; Utterback, E

    2006-06-22

    Applications using high energy ''petawatt-class'' laser drivers operating at repetition rates beyond 0.01 Hz are only now being envisioned. The Mercury laser system is designed to operate at 100 J/pulse at 10 Hz. We investigate the potential of configuring the Mercury laser to produce a rep-rated, ''petawatt-class'' source. The Mercury laser is a prototype of a high energy, high repetition rate source (100 J, 10 Hz). The design of the Mercury laser is based on the ability to scale in energy through scaling in aperture. Mercury is one of several 100 J, high repetition rate (10 Hz) lasers sources currently under development (HALNA, LUCIA, POLARIS). We examine the possibility of using Mercury as a pump source for a high irradiance ''petawatt-class'' source: either as a pump laser for an average power Ti:Sapphire laser, or as a pump laser for OPCPA based on YCa{sub 4}O(BO{sub 3}){sub 3} (YCOB), ideally producing a source approaching 30 J /30 fs /10 Hz--a high repetition rate petawatt. A comparison of the two systems with nominal configurations and efficiencies is shown in Table 1.

  14. A solar simulator-pumped gas laser for the direct conversion of solar energy

    NASA Technical Reports Server (NTRS)

    Weaver, W. R.; Lee, J. H.

    1981-01-01

    Most proposed space power systems are comprised of three general stages, including the collection of the solar radiation, the conversion to a useful form, and the transmission to a receiver. The solar-pumped laser, however, effectively eliminates the middle stage and offers direct photon-to-photon conversion. The laser is especially suited for space-to-space power transmission and communication because of minimal beam spread, low power loss over large distances, and extreme energy densities. A description is presented of the first gas laser pumped by a solar simulator that is scalable to high power levels. The lasant is an iodide C3F7I that as a laser-fusion driver has produced terawatt peak power levels.

  15. Pump and signal combiner for bi-directional pumping of all-fiber lasers and amplifiers.

    PubMed

    Theeg, Thomas; Sayinc, Hakan; Neumann, Jörg; Overmeyer, Ludger; Kracht, Dietmar

    2012-12-17

    We developed an all-fiber component with a signal feedthrough capable of combining up to 6 fiber-coupled multi-mode pump sources to a maximum pump power of 400 W at efficiencies in the range of 89 to 95%, providing the possibility of transmitting a high power signal in forward and in reverse direction. Hence, the fiber combiner can be implemented in almost any fiber laser or amplifier architecture. The complete optical design of the combiner was developed based on ray tracing simulations and confirmed by experimental results. PMID:23263048

  16. 551 nm Generation by sum-frequency mixing of intracavity pumped Nd:YAG laser

    NASA Astrophysics Data System (ADS)

    Dong, Y.; Li, S. T.; Zhang, X. H.

    2012-02-01

    We present for the first time a Nd:YAG laser emitting at 1319 nm intracavity pumped by a 946 nm diode-pumped Nd:YAG laser. A 809 nm laser diode is used to pump the first Nd:YAG crystal emitting at 946 nm, and the second Nd:YAG laser emitting at 1319 nm intracavity pumped at 946 nm. Intracavity sumfrequency mixing at 946 and 1319 nm was then realized in a LBO crystal to reach the yellow range. We obtained a continuous-wave output power of 158 mW at 551 nm with a pump laser diode emitting 18.7 W at 809 nm.

  17. Supersonic diode pumped alkali lasers: Computational fluid dynamics modeling

    NASA Astrophysics Data System (ADS)

    Rosenwaks, Salman; Yacoby, Eyal; Waichman, Karol; Sadot, Oren; Barmashenko, Boris D.

    2015-10-01

    We report on recent progress on our three-dimensional computational fluid dynamics (3D CFD) modeling of supersonic diode pumped alkali lasers (DPALs), taking into account fluid dynamics and kinetic processes in the lasing medium. For a supersonic Cs DPAL with laser section geometry and resonator parameters similar to those of the 1-kW flowing-gas subsonic Cs DPAL [A.V. Bogachev et al., Quantum Electron. 42, 95 (2012)] the maximum achievable output power, ~ 7 kW, is 25% higher than that achievable in the subsonic case. Comparison between semi-analytical and 3D CFD models for Cs shows that the latter predicts much higher maximum achievable output power than the former. Optimization of the laser parameters using 3D CFD modeling shows that very high power and optical-to-optical efficiency, 35 kW and 82%, respectively, can be achieved in a Cs supersonic device pumped by a collimated cylindrical (0.5 cm diameter) beam. Application of end- or transverse-pumping by collimated rectangular (large cross section ~ 2 - 4 cm2) beam makes it possible to obtain even higher output power, > 250 kW, for ~ 350 kW pumping power. The main processes limiting the power of Cs supersonic DPAL are saturation of the D2 transition and large ~ 40% losses of alkali atoms due to ionization, whereas the influence of gas heating is negligibly small. For supersonic K DPAL both gas heating and ionization effects are shown to be unimportant and the maximum achievable power, ~ 40 kW and 350 kW, for pumping by ~ 100 kW cylindrical and ~ 700 kW rectangular beam, respectively, are higher than those achievable in the Cs supersonic laser. The power achieved in the supersonic K DPAL is two times higher than for the subsonic version with the same resonator and K density at the gas inlet, the maximum optical-to-optical efficiency being 82%.

  18. Thermal lensing in Nd:YVO4 laser with in-band pumping at 914 nm

    NASA Astrophysics Data System (ADS)

    Waritanant, Tanant; Major, Arkady

    2016-05-01

    Thermal lensing in an Nd:YVO4 laser system operating at 1064 nm with in-band pumping at 914 nm was characterized. The focal length of the thermal lens in the crystal was calculated using ABCD matrix formalism from the experimental data of the output beam diameter measurements made at different output power levels. The determined focal lengths of thermal lens were as strong as 4.4 diopters at 3.5 W of output power. The experimental results agree well with the finite element analysis of the developed laser system. A numerical comparison of the thermal lensing effect with 914-, 888-, 880-nm pumping, and with a standard 808-nm pumping was also made, demonstrating effective reduction of thermal lensing up to 2.1 times.

  19. Advances in fiber combined pump modules for fiber lasers

    NASA Astrophysics Data System (ADS)

    Crum, Trevor; Romero, Oscar; Li, Hanxuan; Jin, Xu; Towe, Terry; Chyr, Irving; Truchan, Tom; Liu, Daming; Cutillas, Serge; Johnson, Kelly; Park, Sang-Ki; Wolak, Ed; Miller, Robert; Bullock, Robert; Mott, Jeff; Fidric, Bernard; Harrison, James

    2009-02-01

    Fiber combining multiple pump sources for fiber lasers has enabled the thermal and reliability advantages of distributed architectures. Recently, mini-bar based modules have been demonstrated which combine the advantages of independent emitter failures previously shown in single-stripe pumps with improved brightness retention yielding over 2 MW/cm2Sr in compact economic modules. In this work multiple fiber-coupled mini-bars are fiber combined to yield an output of over 400 W with a brightness exceeding 1 MW/cm2Sr in an economic, low loss architecture.

  20. Environmental testing of a diode-laser-pumped Nd:YAG laser and a set of diode-laser-arrays

    NASA Technical Reports Server (NTRS)

    Hemmati, H.; Lesh, J. R.

    1989-01-01

    Results of the environmental test of a compact, rigid and lightweight diode-laser-pumped Nd:YAG laser module are discussed. All optical elements are bonded onto the module using space applicable epoxy, and two 200 mW diode laser arrays for pump sources are used to achieve 126 mW of CW output with about 7 percent electrical-to-optical conversion efficiency. This laser assembly and a set of 20 semiconductor diode laser arrays were environmentally tested by being subjected to vibrational and thermal conditions similar to those experienced during launch of the Space Shuttle, and both performed well. Nevertheless, some damage to the laser front facet in diode lasers was observed. Significant degradation was observed only on lasers which performed poorly in the life test. Improvements in the reliability of the Nd:YAG laser are suggested.

  1. Theoretical studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, W. L.

    1983-01-01

    Metallic vapor lasers of Na2 and Li2 are examined as solar energy converters. The absorbed photons cause transitions to vibrational-rotational levels in an upper electronic state. With broad band absorption the resultant levels can have quantum numbers considerably higher than the upper lasing level. The excited molecule then relaxes to the upper lasing level which is one of the lower vibrational levels in the upper electronic state. The relaxation occurs from collisions, provided the molecule is not quenched into the ground level electronic state. Lasing occurs with a transition to a vibrational level in the lower electronic state. Rough estimates of solar power efficiencies are 1 percent for Na2 and probably a similar figure for Li2. The nondissociative lasers from a family distinct from materials which dissociate to yield an excited atom.

  2. 946 nm Diode Pumped Laser Produces 100mJ

    NASA Technical Reports Server (NTRS)

    Axenson, Theresa J.; Barnes, Norman P.; Reichle, Donald J., Jr.

    2000-01-01

    An innovative approach to obtaining high energy at 946 nm has yielded 101 mJ of laser energy with an optical-to-optical slope efficiency of 24.5%. A single gain module resonator was evaluated, yielding a maximum output energy of 50 mJ. In order to obtain higher energy a second gain module was incorporated into the resonator. This innovative approach produced un-surprised output energy of 101 mJ. This is of utmost importance since it demonstrates that the laser output energy scales directly with the number of gain modules. Therefore, higher energies can be realized by simply increasing the number of gain modules within the laser oscillator. The laser resonator incorporates two gain modules into a folded "M-shaped" resonator, allowing a quadruple pass gain within each rod. Each of these modules consists of a diode (stack of 30 microlensed 100 Watt diode array bars, each with its own fiber lens) end-pumping a Nd:YAG laser rod. The diode output is collected by a lens duct, which focuses the energy into a 2 mm diameter flat to flat octagonal pump area of the laser crystal. Special coatings have been developed to mitigate energy storage problems, including parasitic lasing and amplified spontaneous emission (ASE), and encourage the resonator to operate at the lower gain transition at 946 nm.

  3. An optically pumped hydrogen iodide cascade laser operating in mid-infrared region

    NASA Astrophysics Data System (ADS)

    Ratanavis, Amarin

    2013-06-01

    In recent years, several activities have been toward optically pumped molecular gas lasers as mid-infrared coherent sources. These have been also motivated by the search of suitable laser media for Hollow-core Optical Fiber Gas Laser (HOFGLAS) and the novel beam combiner. To continue these challenge paths, an optically pumped Hydrogen Iodide (HI) laser is explored by using a comprehensive laser model. HI transitions in the communication band (1.5 μm) are attractive due to a potential mean to be excited by commercial available laser systems. Furthermore, its emission coverage in 5 micron region can be useful for many applications, for example, free-space communication and laser spectroscopy. In the laser model, 30 rotational states in each of the 8 vibrational states of HI are taken into account to allow molecular energy transfer processes such as rotational relaxation and vibrational relaxation. A HI laser under pulsed excitation on a second overtone transition with lasing cascade is possible. The complete lasing cascade originates from the terminal pumped state (vibrational state, V = 3) to the vibrational state, V = 2, from the vibrational state, V = 2 to the vibrational state, V = 1 and finally from the vibrational state, V = 1 to the vibrational ground state. For the full lasing cascade, the laser efficiencies can be approached to 70%. In addition, the lasing behavior of the gas pressure related to the molecular relaxation rates and pressure broadening effects is also investigated. Owing to exceptional frequency tuning properties, the laser output can be manipulated to desired frequencies.

  4. Nd:LNA laser optical pumping of He-4 - Application to space magnetometers

    NASA Technical Reports Server (NTRS)

    Slocum, R. E.; Schearer, L. D.; Tin, P.; Marquedant, R.

    1988-01-01

    Results obtained from laser pumping in a helium magnetometer sensor, using a tunable Nd:LNA laser pumped with a high-power diode laser, are reported. It is shown that it was possible to observe both the Hanle signals and the n = 0, p = 1 parametric resonance by monitoring the pumping radiation passing through the cell. As the diode laser-pumped Nd:LNA laser was tuned through the D0, D1, and D2 transitions, three distinct resonance signals were produced. A comparison of the slope of lamp-pumped signals and laser-pumped D1 signals showed that, under otherwise identical conditions, the slope of the D1 laser signal was 45 times greater than the lamp-pumped signal.

  5. Nd:LNA laser optical pumping of He-4 - Application to space magnetometers

    NASA Astrophysics Data System (ADS)

    Slocum, R. E.; Schearer, L. D.; Tin, P.; Marquedant, R.

    1988-12-01

    Results obtained from laser pumping in a helium magnetometer sensor, using a tunable Nd:LNA laser pumped with a high-power diode laser, are reported. It is shown that it was possible to observe both the Hanle signals and the n = 0, p = 1 parametric resonance by monitoring the pumping radiation passing through the cell. As the diode laser-pumped Nd:LNA laser was tuned through the D0, D1, and D2 transitions, three distinct resonance signals were produced. A comparison of the slope of lamp-pumped signals and laser-pumped D1 signals showed that, under otherwise identical conditions, the slope of the D1 laser signal was 45 times greater than the lamp-pumped signal.

  6. Ar-ion-laser-pumped infrared dye laser at 875-1084 nm

    SciTech Connect

    Kato, K.

    1984-12-01

    High-efficiency high-power cw dye-laser operation has been acheived from 875 to 1084 nm by pumping two styryl derivatives with an Ar-ion laser. Peak output powers as high as 900 and 750 mW were obtained around 925 and 980 nm, respectively.

  7. Highly Efficient Operation of Tm:fiber Laser Pumped Ho:YLF Laser

    NASA Technical Reports Server (NTRS)

    Bai, Yingxin; Petros, M.; Yu, Jirong; Petzar, Paul; Trieu, Bo; Chen, Sam; Lee, Hyung; Singh, U.

    2006-01-01

    A 19 W, TEM(sub 00) mode, Ho:YLF laser pumped by continuous wave Tm:fiber laser has been demonstrated at the room temperature. The slope efficiency and optical-to-optical efficiency are 65% and 55%, respectively.

  8. High power, high efficiency, 2D laser diode arrays for pumping solid state lasers

    SciTech Connect

    Rosenberg, A.; McShea, J.C.; Bogdan, A.R.; Petheram, J.C.; Rosen, A.

    1987-11-01

    This document reports the current performance of 2D laser diode arrays operating at 770 nm and 808 nm for pumping promethium and neodymium solid state lasers, respectively. Typical power densities are in excess of 2kw/cm/sup 2/ with overall efficiencies greater than 30%.

  9. Compact KGd(WO4)2 picosecond pulse-train synchronously pumped broadband Raman laser.

    PubMed

    Gao, Xiao Qiang; Long, Ming Liang; Meng, Chen

    2016-08-20

    We demonstrate an efficient approach to realizing an extra-cavity, synchronously pumped, stimulated Raman cascaded process under low repetition frequency (1 kHz) pump conditions. We also construct a compact KGd(WO4)2 (KGW) crystal picosecond Raman laser that has been configured as the developed method. A pulse-train green laser pumped the corresponding 70 mm long KGW crystal Raman cavity. The pulse train contains six pulses, about 800 ps separated, for every millisecond; thus, it can realize synchronous pumping between pump pulse and the pumped Raman cavity. The investigated system produced a collinear Raman laser output that includes six laser lines covering the 532 to 800 nm spectra. This is the first report on an all-solid-state, high-average-power picosecond collinear multi-wavelength (more than three laser components) laser to our knowledge. This method has never been reported on before in the synchronously pumped stimulated Raman scattering (SRS) realm. PMID:27556971

  10. Convergent strand array liquid pumping system

    NASA Technical Reports Server (NTRS)

    Collins, Earl R., Jr. (Inventor)

    1989-01-01

    A surface-tension liquid pumping system is provided by one or more arrays of converging solid monofilament fibers or metal wires (strands) spaced apart at an input end to gather liquid, and gathered close together at the opposite end where menisci forms between wetted strands to force liquid in the direction of convergence of the strands. The liquid pumping system is independent of gravity. It is illustrated as being used in a heat pump having a heating box to vaporize the liquid and a condensing chamber. Condensed liquid is returned by the pumping system to the heating box where it is again vaporized. A vapor tube carries the vapor to the condensing chamber. In that way, a closed system pumps heat from the heating box to the evaporating chamber and from there radiated to the atmosphere.

  11. Compact, efficient, scalable neodymium laser co-doped with activator ions and pumped by visible laser diodes

    NASA Astrophysics Data System (ADS)

    Scheps, Richard

    1994-02-01

    Efficient, low threshold laser emission from a laser crystal doped with chromium and neodymium ions is obtained when pumped by visible laser diodes in the range of 610 nm to 680 nm. A typical laser Cr,Nd:GSGG crystal having an extraordinarily broad absorption bandwidth allows high pump efficiencies when using visible laser diodes, particularly in comparison to the Nd:YAG laser. The broad absorption bandwidth tolerance of the Cr,Nd:GSGG crystal to the pumping wavelengths allows visible diode pumping of the neodymium transition without regard to the wavelength of the visible diodes. Longitudinal or end-pumping to take advantage of the emission properties of the visible laser diodes, a nearly hemispherical laser resonator configuration and other co-doped Cr,Nd laser host materials are disclosed.

  12. Method and system for small scale pumping

    DOEpatents

    Insepov, Zeke; Hassanein, Ahmed

    2010-01-26

    The present invention relates generally to the field of small scale pumping and, more specifically, to a method and system for very small scale pumping media through microtubes. One preferred embodiment of the invention generally comprises: method for small scale pumping, comprising the following steps: providing one or more media; providing one or more microtubes, the one or more tubes having a first end and a second end, wherein said first end of one or more tubes is in contact with the media; and creating surface waves on the tubes, wherein at least a portion of the media is pumped through the tube.

  13. Electron-beam-pumped XeF(C->A) laser energy scaling

    NASA Astrophysics Data System (ADS)

    Litzenberger, Leonard N.; Smith, M. James; Pardue, Albert L., Jr.; Jones, R. W.; Stone, David

    1995-04-01

    The pulse output energy of the electron-beam pumped XeF(C->A) laser system has been increased by nearly two orders of magnitude relative to previously demonstrated values, to 170 J. This performance was achieved in an existing laser device, referred to as Scale-Up, which is pumped by a pair of three meter long, counterpropagating electron beams. The device was equipped with subaperture mirrors which were coated to be reflective in the blue-green portion of the visible spectrum. The reflectivity of the output coupler of the folded stable cavity was carefully selected to maximize the laser output energy. This choice involved a trade-off between the amount of time required for the intracavity flux to build up from noise to the saturation level, and the energy extraction efficiency under steady state oscillating conditions. The observed optical pulse duration of 0.8 microsecond(s) was in good agreement with the prediction of a flux buildup model which was developed during the design phase of this effort. The demonstrated specific output energy of 1.7 J/L was comparable to that previously achieved in small scale lasing tests which were also performed under free-running conditions. This proved that the XeF(C->A) laser system is volumetrically scalable to high output energy per pulse. No evidence of laser oscillation on the competing XeF(B->X) transition was observed. The pulse-average electron-beam pump rate was 140 kW/cm3, and the electron-beam pulse duration was 1.7 microsecond(s) . The ability to operate this low gain laser system at a moderate pump rate greatly relaxes the constraints on the design of the electron gun and pulse power subsystems, making construction of a high average power laser device possible.

  14. Solid state laser systems for space application

    NASA Technical Reports Server (NTRS)

    Kay, Richard B.

    1994-01-01

    Since the last report several things have happened to effect the research effort. In laser metrology, measurements using Michelson type interferometers with an FM modulated diode laser source have been performed. The discrete Fourier transform technique has been implemented. Problems associated with this technique as well as the overall FM scheme were identified. The accuracy of the technique is not at the level we would expect at this point. We are now investigating the effect of various types of noise on the accuracy as well as making changes to the system. One problem can be addressed by modifying the original optical layout. Our research effort was also expanded to include the assembly and testing of a diode pumped\\Nd:YAG laser pumped\\Ti sapphire laser for possible use in sounding rocket applications. At this stage, the diode pumped Nd:YAG laser has been assembled and made operational.

  15. High-power high-repetition-rate copper-vapor-pumped dye laser

    SciTech Connect

    Singh, S.; Dasgupta, K.; Kumar, S.; Manohar, K.G.; Nair, L.G.; Chatterjee, U.K. . Laser and Plasma Technology Div.)

    1994-06-01

    The design and development of an efficient high average power dye laser oscillator-amplifier system developed at the Laser and Plasma Technology Division, Bhabha Atomic Research Centre, is reported. The dye laser is pumped by a 6.5-kHz repetition rate copper vapor laser. The signal beam to the dye amplifier is obtained from an efficient narrow-band grazing incidence grating (GIG) dye laser oscillator incorporating a multiple prism beam expander. Amplifier extraction efficiency up to 40% was obtained in a single amplifier stage, using rhodamine 6G (Rh6G) in ethanol. The authors have also demonstrated simultaneous amplification of two laser beams at different wavelengths in the same dye amplifier cell.

  16. Nd:GdVO4 ring laser pumped by laser diodes

    NASA Astrophysics Data System (ADS)

    Hao, E. J.; Li, T.; Wang, Z. D.; Zhang, Y.

    2013-02-01

    The design and operation of a laser diode-pumped Nd:GdVO4 ring laser is described. A composite crystal (Nd:GdVO4/YVO4) with undoped ends is single-end pumped by a fiber-coupled laser diode (LD) at 808 nm. A four-mirror ring cavity is designed to keep the laser operating unidirectionally, which eliminates spatial hole burning in the standing-wave cavity. This laser can operate either as continuous wave (CW) or Q-switched. The single-frequency power obtained was 9.1 W at 1063 nm. Q-switched operation produced 0.23 mJ/pulse at 20 kHz in the fundamental laser.

  17. High-Reliability Pump Module for Non-Planar Ring Oscillator Laser

    NASA Technical Reports Server (NTRS)

    Liu, Duncan T.; Qiu, Yueming; Wilson, Daniel W.; Dubovitsky, Serge; Forouhar, Siamak

    2007-01-01

    We propose and have demonstrated a prototype high-reliability pump module for pumping a Non-Planar Ring Oscillator (NPRO) laser suitable for space missions. The pump module consists of multiple fiber-coupled single-mode laser diodes and a fiber array micro-lens array based fiber combiner. The reported Single-Mode laser diode combiner laser pump module (LPM) provides a higher normalized brightness at the combined beam than multimode laser diode based LPMs. A higher brightness from the pump source is essential for efficient NPRO laser pumping and leads to higher reliability because higher efficiency requires a lower operating power for the laser diodes, which in turn increases the reliability and lifetime of the laser diodes. Single-mode laser diodes with Fiber Bragg Grating (FBG) stabilized wavelength permit the pump module to be operated without a thermal electric cooler (TEC) and this further improves the overall reliability of the pump module. The single-mode laser diode LPM is scalable in terms of the number of pump diodes and is capable of combining hundreds of fiber-coupled laser diodes. In the proof-of-concept demonstration, an e-beam written diffractive micro lens array, a custom fiber array, commercial 808nm single mode laser diodes, and a custom NPRO laser head are used. The reliability of the proposed LPM is discussed.

  18. Discretely tunable multiwavelength diode-pumped Nd:YALO laser

    NASA Astrophysics Data System (ADS)

    Poirier, P.; Hanson, F.

    1996-01-01

    Operation of a moderate-to-high repetition-rate Q-switched quadrupled diode-pumped Nd:YALO laser discretely tunable between 266 and 275 nm is reported. Intracavity frequency doubling of the fundamental yielded 5.4 and 4.4 mJ at 532 and 550 nm, respectively, at a 600-Hz repetition rate. The laser radiation was frequency quadrupled to the UV external to the cavity with an output of 0.28 and 0.24 mJ at 266 and 275 nm, respectively. Astigmatic focal lengths that are due to thermal lensing effects of the Nd:YALO rod in the side-pumping geometry are presented.

  19. Laser head for simultaneous optical pumping of several dye lasers. [with single flash lamp

    NASA Technical Reports Server (NTRS)

    Mumola, P. B.; Mcalexander, B. T. (Inventor)

    1975-01-01

    The invention is a laser head for simultaneous pumping several dye lasers with a single flash lamp. The laser head includes primarily a multi-elliptical cylinder cavity with a single flash lamp placed along the common focal axis of the cavity and with capillary tube dye cells placed along each of the other focal axes of the cavity. The inside surface of the cavity is polished. Hence, the single flash lamp supplies the energy to the several dye cells.

  20. Efficient holmium:yttrium lithium fluoride laser longitudinally pumped by a semiconductor laser array

    NASA Technical Reports Server (NTRS)

    Hemmati, H.

    1987-01-01

    Optical pumping of a holmium:yttrium lithium floride (Ho:YLF) crystal with a 790-nm continuous-wave diode-laser array has generated 56 mW of 2.1-micron laser radiation with an optical-to-optical conversion slope efficiency of 33 percent while the crystal temperature is held at 77 K. The lasing threshold occurs at 7 mW of input power, and laser operation continues up to a crystal temperature of 124 K.

  1. Diode-side-pumped, passively Q-switched Yb:LuAG laser

    NASA Astrophysics Data System (ADS)

    Kaskow, Mateusz; Galecki, Lukasz; Jabczynski, Jan K.; Skorczakowski, Marek; Zendzian, Waldemar; Sulc, Jan; Nemec, Michal; Jelinkova, Helena

    2015-10-01

    A high-gain, diode-side-pumped Yb:LuAG slab laser was designed and investigated for use at room temperature. Pumping occurred from a fast-axis collimated 2D laser diode stack emitting at a wavelength of 970 nm, with 0.8 J over a duration of 0.8 ms. The pump scheme, which enabled efficient mode matching and high gain, was analysed and experimentally verified for different dopant levels. An energy of 100 mJ with 23% slope efficiency in a near fundamental mode was achieved in the free-running regime. A peak power of 2.5 MW and a pulse energy of 10.1 mJ were demonstrated in passive Q-switching by means of a Cr:YAG saturable absorber with 39% initial transmission. The study defined the indications for optimizing such a system.

  2. Longitudinal discharge pumped low-pressure XeCl laser

    SciTech Connect

    Fedorov, A I

    2013-10-31

    We have studied output parameters of a XeCl and a N{sub 2} laser pumped by a longitudinal discharge with automatic spark UV preionisation. The output parameters of a low-pressure (30 Torr) XeCl laser operating with Ar, Ne and He as buffer gases or with no buffer gas have been optimised for the first time. The laser generated 5-ns FWHM pulses with an average power of 0.5 mW and output energy of 0.15 mJ. Under longitudinal discharge pumping, an output energy per unit volume of 1.8 J L{sup -1} atm{sup -1} was reached using helium as a buffer gas. With argon-containing and buffer-free mixtures, it was 1.5 J L{sup -1} atm{sup -1}. The N{sub 2} laser generated 2.5-ns FWHM pulses with an average power of 0.35 mW and output energy of 0.05 mJ. (lasers)

  3. Mercury and Beyond: Diode-Pumped Solid-State Lasers for Inertial Fusion Energy

    SciTech Connect

    Bibeau, C.; Beach, R.J.; Bayramian, A.; Chanteloup, J.C.; Ebbers, C.A.; Emanuel, M.A.; Orth, C.D.; Rothenberg, J.E.; Schaffers, K.I.; Skidmore, J.A.; Sutton, S.B.; Zapata, L.E.; Payne, S.A.; Powell, H.T.

    1999-10-19

    We have begun building the ''Mercury'' laser system as the first in a series of new generation diode-pumped solid-state lasers for inertial fusion research. Mercury will integrate three key technologies: diodes, crystals, and gas cooling, within a unique laser architecture that is scalable to kilojoule energy levels for fusion energy applications. The primary performance goals include 10% electrical efficiencies at 10 Hz and 100 J with a 2-10 ns pulse length at 1.047 pm wavelength. When completed, Mercury will allow rep-rated target experiments with multiple target chambers for high energy density physics research.

  4. Femtosecond Laser--Pumped Source of Entangled Photons for Quantum Cryptography Applications

    SciTech Connect

    Pan, D.; Donaldson, W.; Sobolewski, R.

    2007-07-31

    We present an experimental setup for generation of entangled-photon pairs via spontaneous parametric down-conversion, based on the femtosecond-pulsed laser. Our entangled-photon source utilizes a 76-MHz-repetition-rate, 100-fs-pulse-width, mode-locked, ultrafast femtosecond laser, which can produce, on average, more photon pairs than a cw laser of an equal pump power. The resulting entangled pairs are counted by a pair of high-quantum-efficiency, single-photon, silicon avalanche photodiodes. Our apparatus is intended as an efficient source/receiver system for the quantum communications and quantum cryptography applications.

  5. Indication of Local Laser Pump Depletion via Transmitted Self-Guided Laser Light

    SciTech Connect

    Pak, A. E.; Marsh, K. A.; Ralph, J. E.; Lu, W.; Clayton, C. E.; Joshi, C.

    2009-01-22

    In recent experiments it has been shown that an ultra-intense, ultra-short laser pulse can be self-guided over tens of Rayleigh lengths in an underdense plasma where {tau}(FWHM of the laser pulse) is on the order of the plasma wavelength ({lambda}{sub p}). Using an imaging spectrograph, the frequency of the transmitted laser pulse was spatially and spectrally resolved at the exit of 3, 5, and 8 mm long plasmas. The mechanism of laser pump depletion was studied by observing the amount that the transmitted laser pulse's spectrum was red shifted in wavelength through the interaction with the self-guiding plasma wave.

  6. Resonantly pumped, erbium-doped, GSGG, 2.8 micron, solid state laser with energy recycling and high slope efficiency

    NASA Astrophysics Data System (ADS)

    Esterowitz, Leon; Stoneman, Robert

    1992-05-01

    A laser system and a method for producing a laser emission at a wavelength of approximately 2.8 microns are presented. The system and method have a quantum efficiency of at least unity and a slope efficiency of about 36 percent. The laser system is comprised of the following: a laser cavity defined by first and second reflective elements with one of the reflective elements operating as an output coupler; a crystal disposed in the laser cavity and having a GSGG host material doped with a preselected percent concentration of erbium, the GSGG host material and preselected percent concentration of erbium being selected so as to provide a quantum efficiency of at least unity by the (sup 4)I(sub 13/2) + (sup 4)I(sub 13/2) yields (sup 4)I(sub9/2) + (sup 4)I(sub 15/2) upconversion process and a slope efficiency of about 36 percent when the crystal is resonantly pumped; and a resonant pump laser for directly pumping the (sup 4)I(sub 11/2) upper laser state of the erbium with a pump beam to cause the crystal to produce a laser emission corresponding to the (sup 4)I(sub 11/2) yields (sup 4)I(sub 13/2) laser transition having a wavelength of substantially 2.8 microns.

  7. Frequency domain approach for time-resolved pump-probe microscopy using intensity modulated laser diodes

    NASA Astrophysics Data System (ADS)

    Miyazaki, J.; Kawasumi, K.; Kobayashi, T.

    2014-09-01

    We present a scheme for time-resolved pump-probe microscopy using intensity modulated laser diodes. The modulation frequencies of the pump and probe beams are varied up to 500 MHz with fixed frequency detuning typically set at 15 kHz. The frequency response of the pump-probe signal is detected using a lock-in amplifier referenced at the beat frequency. This frequency domain method is capable of characterizing the nanosecond to picosecond relaxation dynamics of sample species without the use of a high speed detector or a high frequency lock-in amplifier. Furthermore, as the pump-probe signal is based on the nonlinear interaction between the two laser beams and the sample, our scheme provides better spatial resolution than the conventional diffraction-limited optical microscopes. Time-resolved pump-probe imaging of fluorescence beads and aggregates of quantum dots demonstrates that this method is useful for the microscopic analysis of optoelectronic devices. The system is implemented using compact and low-cost laser diodes, and thus has a broad range of applications in the fields of photochemistry, optical physics, and biological imaging.

  8. High-brightness, fiber-coupled pump modules in fiber laser applications

    NASA Astrophysics Data System (ADS)

    Hemenway, Marty; Urbanek, Wolfram; Hoener, Kylan; Kennedy, Keith W.; Bao, Ling; Dawson, David; Cragerud, Emily S.; Balsley, David; Burkholder, Gary; Reynolds, Mitch; Price, Kirk; Haden, Jim; Kanskar, Manoj; Kliner, Dahv A.

    2014-03-01

    High-power, high-brightness, fiber-coupled pump modules enable high-performance industrial fiber lasers with simple system architectures, multi-kW output powers, excellent beam quality, unsurpassed reliability, and low initial and operating costs. We report commercially available (element™), single-emitter-based, 9xx nm pump sources with powers up to 130 W in a 105 μm fiber and 250 W in a 200 μm fiber. This combination of high power and high brightness translates into improved fiber laser performance, e.g., simultaneously achieving high nonlinear thresholds and excellent beam quality at kW power levels. Wavelength-stabilized, 976 nm versions of these pumps are available for applications requiring minimization of the gain-fiber length (e.g., generation of high-peak-power pulses). Recent prototypes have achieved output powers up to 300 W in a 200 μm fiber. Extensive environmental and life testing at both the chip and module level under accelerated and real-world operating conditions have demonstrated extremely high reliability, with innovative designs having eliminated package-induced-failure mechanisms. Finally, we report integrated Pump Modules that provide < 1.6 kW of fiber-coupled power conveniently formatted for fiber-laser pumping or direct-diode applications; these 19" rack-mountable, 2U units combine the outputs of up to 14 elements™ using fused-fiber combiners, and they include high-efficiency diode drivers and safety sensors.

  9. Influences of pump beam distribution on thermal lensing spherical aberration in an LD end-pumped Nd:YAG laser

    NASA Astrophysics Data System (ADS)

    Song, Xiao-lu; Li, Bing-bin; Guo, Zhen; Wang, Shi-yu; Cai, De-fang; Wen, Jian-guo

    2009-12-01

    A numerical investigation is made on the thermal lensing and spherical aberration effect in an LD end-pumped Nd:YAG laser. Based on the finite element method (FEM), the laser rod temperature distribution is calculated and the focal length of the thermal lens is deduced, the influences of pump beam on the thermal lensing spherical aberration are mainly studied. The results show the thermal lens which focal length varied with the radial coordinate r is not an ideal lens. Given the heat dissipation boundary conditions, the radial dependent focal length will be shortened when the pump power raised or the waist radius of the pump beam reduced, meanwhile the radial differences of the focal length will decrease when the pump power increased. For a Super-Gaussian profile pump beam, the higher the exponent number, the more similar to flat top the pump beam is, and the less the radial differences of the focal length are.

  10. Advancements in high-power high-brightness laser bars and single emitters for pumping and direct diode application

    NASA Astrophysics Data System (ADS)

    An, Haiyan; Jiang, Ching-Long J.; Xiong, Yihan; Zhang, Qiang; Inyang, Aloysius; Felder, Jason; Lewin, Alexander; Roff, Robert; Heinemann, Stefan; Schmidt, Berthold; Treusch, Georg

    2015-03-01

    We have continuously optimized high fill factor bar and packaging design to increase power and efficiency for thin disc laser system pump application. On the other hand, low fill factor bars packaged on the same direct copper bonded (DCB) cooling platform are used to build multi-kilowatt direct diode laser systems. We have also optimized the single emitter designs for fiber laser pump applications. In this paper, we will give an overview of our recent advances in high power high brightness laser bars and single emitters for pumping and direct diode application. We will present 300W bar development results for our next generation thin disk laser pump source. We will also show recent improvements on slow axis beam quality of low fill factor bar and its application on performance improvement of 4-5 kW TruDiode laser system with BPP of 30 mm*mrad from a 600 μm fiber. Performance and reliability results of single emitter for multiemitter fiber laser pump source will be presented as well.

  11. Highly efficient neodymium:yttrium aluminum garnet laser end pumped by a semiconductor laser array

    NASA Technical Reports Server (NTRS)

    Sipes, D. L.

    1985-01-01

    In recent experiments, 80-mW CW power in a single mode has been achieved from a neodymium:yttrium aluminum garnet (Nd:YAG) laser with only 1 W of electrical power input to a single semiconductor laser array pump. This corresponds to an overall efficiency of 8 percent, the highest reported CW efficiency for a Nd:YAG laser. A tightly focused semiconductor laser end pump configuration is used to achieve high pumping intensities (on the order of 1 kW/sq cm), which in turn causes the photon to photon conversion efficiency to approach the quantum efficiency (76 percent for Nd:YAG at 1.06 microns pumped at 0.810 micron). This is achieved despite the dual-lobed nature of the pump. Through the use of simple beam-combining schemes (e.g., polarization coupling and multireflection point pumping), output powers over 1 W and overall electrical to optical efficiencies as high as 10 percent are expected.

  12. Magnetohydrodynamic pump with a system for promoting flow of fluid in one direction

    DOEpatents

    Lemoff, Asuncion V.; Lee, Abraham P.

    2010-07-13

    A magnetohydrodynamic pump for pumping a fluid. The pump includes a microfluidic channel for channeling the fluid, a MHD electrode/magnet system operatively connected to the microfluidic channel, and a system for promoting flow of the fluid in one direction in the microfluidic channel. The pump has uses in the medical and biotechnology industries for blood-cell-separation equipment, biochemical assays, chemical synthesis, genetic analysis, drug screening, an array of antigen-antibody reactions, combinatorial chemistry, drug testing, medical and biological diagnostics, and combinatorial chemistry. The pump also has uses in electrochromatography, surface micromachining, laser ablation, inkjet printers, and mechanical micromilling.

  13. Hypersonic gasdynamic laser system

    SciTech Connect

    Foreman, K.M.; Maciulaitis, A.

    1990-05-22

    This patent describes a visible, or near to mid infra-red, hypersonic gas dynamic laser system. It comprises: a hypersonic vehicle for carrying the hypersonic gas dynamic laser system, and also providing high energy ram air for thermodynamic excitation and supply of the laser gas; a laser cavity defined within the hypersonic vehicle and having a laser cavity inlet for the laser cavity formed by an opening in the hypersonic vehicle, such that ram air directed through the laser cavity opening supports gas dynamic lasing operations at wavelengths less than 10.6{mu} meters in the laser cavity; and an optical train for collecting the laser radiation from the laser cavity and directing it as a substantially collimated laser beam to an output aperture defined by an opening in the hypersonic vehicle to allow the laser beam to be directed against a target.

  14. Self-pumping solar heating system with geyser pumping action

    SciTech Connect

    Haines, E.L.; Bartera, R.E.

    1984-10-23

    A self-pumping solar heating system having a collector including a multitude of small diameter riser tubes from which heated liquid is pumped into a header by a geyser action. A vapor condenser assures a header pressure conducive to bubble nucleation in the riser tube upper end segments. The level of liquid within the header or its outlet is higher than the liquid level in the riser tubes to produce a gravity imbalance capable of circulating heated liquid past a storage heat exchanger, below the header, and then upwardly through the closed vapor condenser in the header prior to return to a collector inlet manifold. A modified header utilizes an open vapor condenser in vapor communication with the collector header.

  15. Injection locking of a diode-pumped Nd:YAG laser at 946 nm

    SciTech Connect

    Hollemann, G.; Peik, E.; Rusch, A.; Walther, H.

    1995-09-15

    Injection locking in the quasi-three-level laser system Nd:YAG {sup 4}{ital F}{sub 3/2}--{sup 4}{ital I}{sub 9/2} at 946 nm is reported. The master and slave oscillators are pumped by laser diodes. The master oscillator is frequency stabilized to a high-finesse cavity, resulting in a laser linewidth of less than 10 Hz. Using intracavity frequency doubling of the slave oscillator, we achieve a single-mode output power of 60 mW at 473 nm. The laser radiation was frequency quadrupled, resulting in an UV power of 0.55 mW at 236.5 nm. The laser system was used to excite a strongly forbidden In{sup +} transition, proposed as a new optical frequency standard. {copyright} 1995 Optical Society of America

  16. Observation of enhanced thermal lensing due to near-Gaussian pump energy deposition in a laser-diode side-pumped Nd:YAG laser

    NASA Technical Reports Server (NTRS)

    Welford, David; Rines, David M.; Dinerman, Bradley J.; Martinsen, Robert

    1992-01-01

    The authors report operation of a laser-diode side-pumped Nd:YAG laser with a novel pumping geometry that ensures efficient conversion of pump energy into the TEM00 mode. Significant enhancement of thermally induced lensing due to the near-Gaussian energy deposition profile of the pump radiation was observed. An induced lens of approximately 3.2-m focal length was measured at average incident pump powers of only 3.2 W (corresponding to a 0.6 W heat load).

  17. Seventeen psec pulses from a nitrogen laser-pumped short-cavity rhodamine 6G dye laser

    SciTech Connect

    Liesegang, G.W.

    1983-08-15

    We wish to report the generation of 17-psec pulses of 200-kW intensity from a nitrogen-pumped rhodamine 6G short-cavity dye laser. This dye laser has a cavity length of 120 ..mu..m and is axially pumped by the nitrogen laser. (AIP)

  18. Resonantly pumped, erbium-doped, GSGG, 2.8 micron, solid state laser with energy recycling and high slope efficiency

    NASA Astrophysics Data System (ADS)

    Esterowitz, Leon; Stoneman, Robert C.

    1993-04-01

    This invention is a laser system and method for producing a laser emission at a wavelength of substantially 2.8 microns and having a quantum efficiency of at least unity and a slope efficiency of about 36%. In a preferred embodiment of the invention, the laser system comprises a laser cavity defined by first and second reflective elements with one of the reflective elements operating as an output coupler; a crystal disposed in the laser cavity and having a GSGG host material doped with a preselected percent concentration of erbium, the GSGG host material and preselected percent concentration of erbium being selected so as to provide a quantum efficiency of at least unity by the 4I13/2 + 4I13/2 right arrow 4I9/2 + 4I15/2 upconversion process and a slope efficiency of about 36% when the crystal is resonantly pumped; and a resonant pump laser for directly pumping the 4I11/2 upper laser state of the erbium with a pump beam to cause the crystal to produce a laser emission corresponding to the 4I11/2 right arrow 4I13/2 laser transition having a wavelength of substantially 2.8 microns.

  19. Performance results on the laser portion of the Keck laser guide star system

    SciTech Connect

    Cooke, J B; Danforth, P M; Erbert, G V; Feldman, M; Friedman, H W; Gavel, D T; Jenkins, S L; Jones, H E; Kanz, V K; Kuklo, T; Newman, M J; Pierce, E L; Presta, R W; Salmon, J T; Thompson, G R; Wong, N J

    1998-09-29

    The Laser Guide Star (LGS) system for the Keck II, 10 m telescope consists of two separate but interconnected systems, the laser and the adaptive optics bench. The laser portion of the LGSl is a set of five frequency doubled YAG lasers pumping a master oscillator-power amplifier dye chain to produce up to 30 W of 589 p at 26 kHz of tuned light. Presently the laser system has been set up at the Keck facility in Waimea, HI and is undergoing test and evaluation. When it will be set up on the Keck II telescope, the pump lasers, dye master oscillator and associated control equipment will be located on the dome floor and the dye laser amplifiers, beam control system and diagnostics will be mounted directly on the telescope as shown in Fig. 1, Extensive use of fiber optics for both transmission of the oscillator pulse and the pump laser light has been used.

  20. Laser rods with undoped, flanged end-caps for end-pumped laser applications

    DOEpatents

    Meissner, Helmuth E.; Beach, Raymond J.; Bibeau, Camille; Sutton, Steven B.; Mitchell, Scott; Bass, Isaac; Honea, Eric

    1999-01-01

    A method and apparatus for achieving improved performance in a solid state laser is provided. A flanged, at least partially undoped end-cap is attached to at least one end of a laserable medium. Preferably flanged, undoped end-caps are attached to both ends of the laserable medium. Due to the low scatter requirements for the interface between the end-caps and the laser rod, a non-adhesive method of bonding is utilized such as optical contacting combined with a subsequent heat treatment of the optically contacted composite. The non-bonded end surfaces of the flanged end-caps are coated with laser cavity coatings appropriate for the lasing wavelength of the laser rod. A cooling jacket, sealably coupled to the flanged end-caps, surrounds the entire length of the laserable medium. Radiation from a pump source is focussed by a lens duct and passed through at least one flanged end-cap into the laser rod.