Sample records for pumped dye laser

  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. Nonlinear dye response under nitrogen laser pumping

    NASA Astrophysics Data System (ADS)

    Milani, Marziale; Ferraro, Lorenzo

    2002-03-01

    Nitrogen lasers have been used since many years to make dye solutions to lase. A nitrogen laser (337.1 nm) TEA at atmospheric pressure has been built in our laboratory. It has been characterized and used to pump cells of different sizes containing different dyes: Rhodamine 6G, Coumarin 440, DOTCI and pyranine. As a preliminary result it has been shown that pyranine can lase, and this happens at very low threshold. Moreover, we have found that, independently on the dye concentration in the solvent, the dyes under consideration can be grouped into two major classes of behavior: Rhodamine 6G and DOTCI can lase both axially and transversally; Coumarin 440 and pyranine can lase only axially. Other intriguing features will be discussed and attention will be devoted to simultaneous multiple beam generation, superfluorescence and distributed axial pumping of dye solutions.

  3. 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.

  4. Dye laser model with pump and quantum fluctuations; White noise

    Microsoft Academic Search

    P. Jung; Th. Leiber; H. Risken

    1987-01-01

    We discuss a single mode dye laser model with two stochastically fluctuating forces representing pump and quantum fluctuations. We investigate the different influences of white pump and quantum fluctuations on the statistical properties of the laser light intensity. The corresponding Fokker-Planck equations are solved by means of scalar continued fractions. Stationary as well as instationary properties such as distribution functions,

  5. Tunable repetitively pulsed flashlamp-pumped dye lasers

    SciTech Connect

    Dzyubenko, M I; Maslov, V V; Pelipenko, V P; Shevchenko, V V [A.Ya. Usikov Institute of Radiophysics and Electronics, National Academy of Sciences of Ukraine, Khar'kov (Ukraine)

    1998-12-31

    An experimental investigation was made of the spatioangular and spectral-energy characteristics of high-power tunable repetitively pulsed flashlamp-pumped dye lasers. A high directionality of the output radiation was attained in a wide range of the concentrations of the active molecules when aqueous solutions of dyes, in particular an inclusion complex of coumarin-120 and {beta}-cyclodextrin, were used. Such high directionality was obtained for alcohol and water-alcohol solutions only when the concentrations of these molecules were low. Continuous variation of the tuning range of lasers of this class should be possible by the use of suitable mixtures of efficient donor and acceptor dyes. (lasers)

  6. Comparative laser performances of pyrromethene 567 and rhodamine 6G dyes in copper vapour laser pumped dye lasers

    NASA Astrophysics Data System (ADS)

    Ray, A. K.; Kundu, S.; Sasikumar, S.; Rao, C. S.; Mula, S.; Sinha, S.; Dasgupta, K.

    2007-05-01

    Narrowband laser performances and photochemical stability of alcoholic solutions of pyrromethene 567 and rhodamine 6G dyes, under high-repetition rate copper vapour laser (at 510 nm), as well as, high-peak intensity Nd:YAG laser (at 532 nm) excitation have been investigated. We have observed that pyrromethene 567 dye solutions offer higher efficiency, wider tuning range, but lower photochemical stability and higher lasing threshold than that of rhodamine 6G dye solutions. An addition of about 100 mM DABCO, as a singlet oxygen quencher, in pyrromethene 567 dye solutions improved its photochemical stability close to that of rhodamine 6G. The observation of higher slope efficiency, in spite of higher threshold pump energy for pyrromethene 567 dye than that of rhodamine 6G dye solutions, was explained by a predictive model on gain characteristics of both dye solutions as a function of pump energy.

  7. 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.

  8. The construction and operation of a flashlamp pumped tunable narrow linewidth dye laser 

    E-print Network

    Hilty, Bruce Robert

    1979-01-01

    THE CONSTRUCTION AND OPERATION OF A FLASHLAMP PUMPED TUNABLE NARROW LINEWIOTH DYE LASER A Thesis by BRUCE ROBERT HILTY Submitted to the Graduate College of Texas A&M University i n Partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1979 Major Subject: Physics THE CONSTRUCTION AND OPERATION OF A FLASHLAMP PUMPED TUNABLE NARROll LINEWIDTH DYE LASER A Thesis by BRUCE ROBERT HILTY Approved as to style and content by: (Chairman of Committ e) (Member...

  9. 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.

  10. Synchronously pumped visible laser dye with twice the efficiency of Rhodamine 6G.

    PubMed

    O'Neil, M P

    1993-01-01

    An uncommon pyrromethene laser dye is characterized for ultrafast pulse generation under synchronous pumping and is found to be exceptionally efficient, producing nearly 1 W of output power at 565 nm when pumped with 2 W at 532 nm. PMID:19798342

  11. The copper-pumped dye laser system at Lawrence Livermore National Laboratory

    SciTech Connect

    Hackel, R.P.; Warner, B.E.

    1993-01-12

    The Atomic Vapor Isotope Separation (AVLIS) Program has developed a high-average-power, pulsed, tunable, visible laser system. Testing of this hardware is in progress at industrial scales. The copper-dye Laser system is prototypical of a basic module of a uranium-AVLIS plant The laser demonstration facility (LDF) system consists of copper vapor lasers arranged in oscillator-amplifier chains providing optical pump power to dye-laser master-oscillator-power-amplifier chains. This system is capable of thousands of watts (average) tunable between 550 and 650 mm. The copper laser system consists of 12 chains operating continuously. The copper lasers operate at nominally 4.4 kHz, with 50 ns pulse widths and produce 20 W at near the diffraction limit from oscillators and >250 W from each amplifier. Chains consist of an oscillator and three amplifiers and produce >750 W average, with availabilities >95% (i.e., >8300 h/y). The total copper laser system power averages {approximately}9000 W and has operated at over 10,000 W for extended intervals. The 12 copper laser beams are multiplexed and delivered to the dye laser system where they pump multiple dye laser chains. Each dye chain consists of a master oscillator and three or four power amplifiers. The master oscillator operates at nominally 100 mW with a 50 MHz single mode bandwidth. Sustained dye chain powers are up to 1400 W with dye conversion efficiency >50%, ASE content <5%, and wavefront quality correctable to <{lambda}/10 RMS, using deformable mirrors. The dye laser system is capable of repetition rates which are multiples of 4.4 kHz, up to 26 kHz.

  12. The copper-pumped dye laser system at Lawrence Livermore National Laboratory

    SciTech Connect

    Hackel, R.P.; Warner, B.E.

    1993-01-12

    The Atomic Vapor Isotope Separation (AVLIS) Program has developed a high-average-power, pulsed, tunable, visible laser system. Testing of this hardware is in progress at industrial scales. The copper-dye Laser system is prototypical of a basic module of a uranium-AVLIS plant The laser demonstration facility (LDF) system consists of copper vapor lasers arranged in oscillator-amplifier chains providing optical pump power to dye-laser master-oscillator-power-amplifier chains. This system is capable of thousands of watts (average) tunable between 550 and 650 mm. The copper laser system consists of 12 chains operating continuously. The copper lasers operate at nominally 4.4 kHz, with 50 ns pulse widths and produce 20 W at near the diffraction limit from oscillators and >250 W from each amplifier. Chains consist of an oscillator and three amplifiers and produce >750 W average, with availabilities >95% (i.e., >8300 h/y). The total copper laser system power averages [approximately]9000 W and has operated at over 10,000 W for extended intervals. The 12 copper laser beams are multiplexed and delivered to the dye laser system where they pump multiple dye laser chains. Each dye chain consists of a master oscillator and three or four power amplifiers. The master oscillator operates at nominally 100 mW with a 50 MHz single mode bandwidth. Sustained dye chain powers are up to 1400 W with dye conversion efficiency >50%, ASE content <5%, and wavefront quality correctable to <[lambda]/10 RMS, using deformable mirrors. The dye laser system is capable of repetition rates which are multiples of 4.4 kHz, up to 26 kHz.

  13. Synchronous pumping of picosecond dye laser using high efficiency second harmonic generation from optical fibres

    Microsoft Academic Search

    N. M. Lawandy; J. P. Bernardin; R. L. MacDonald; G. Demouchy

    1991-01-01

    The stable operation of a mode-locked dye laser synchronously pumped by the second harmonic of an Nd:YAG laser produced in an Nd codoped germanosilicate optical fiber is reported. The optical fiber preparation technique, which results in a second harmonic conversion efficiency of 2 percent, is described. This optical fiber SHG conversion efficiency is the highest reported to date using a

  14. Ultraviolet high power near fundamental mode output from an argon ion laser with applications as a ring dye laser pump source for blue and near UV dyes

    Microsoft Academic Search

    Timothy J. Johnston

    1989-01-01

    A wavelength and power survey of the 275 nm to 400 nm region has been made with commercial large-frame argon ion lasers operating at elevated discharge currents and various gas pressures. The UV output in the 300 nm to 386 nm region is separated into three groups of lines and used to pump several dyes giving single-frequency tunable outputs from

  15. Four-wave mixing in the PDL2 dye laser pumped by the frequency-doubled DCR-3 YAG:Nd laser

    Microsoft Academic Search

    Chang-yong Li; Yuqiang Jiang; Wang-bao Yin; Lirong Wang; Suotang Jia

    2002-01-01

    When the PDL-2 dye laser was pumped longitudinally by the frequency-doubled DCR-3 YAG:Nd laser, it is found that two coherent radiations are generated by one dye medium (LDS751 or LDS750). Aside from the expected dye laser output, there appears another coherent radiation generated by a four-wave mixing process. This is caused by the YAG:Nd laser's two longitudinal mode. As far

  16. Construction and Characterization of a Nanosecond Nd:YAG Laser Pumped Distributed Feedback Dye Laser Generating Picosecond Pulses

    NASA Astrophysics Data System (ADS)

    Clark, Timothy; Weckerly, Chris; Ujj, Laszlo

    2013-03-01

    We have constructed a Distributed Feedback Dye Laser (DFDL) using interferometric pumping. DFDL works according to the dynamic modulation of the gain medium creating short pulses. Shortening of the pulses, stability, and dynamic range of the DFDL were investigated. Pulses were measured with the help of a photodiode with a 30 picosecond response time. Traces were recorded with a Tektronics DSA73304D (33GHz) digital serial analyser. The gain medium contains an ethanol solution of Rhodamine 590 dye and DODCI saturable absorber. Increasing the concentration of DODCI saturable absorber resulted in significant pulse shortening (150 to 54 picoseconds). Single pulse generation was achieved when the power of the pump laser was adjusted 10 percent above the laser threshold. The central wavelength of the laser pulses was 587 nm. The mathematical modeling, optical layout of the DFDL, and the results of the temporal and spectral characterization of the laser are presented on the poster. The development of the DFDL will lead to an extensive investigation of short pulse dye lasers for educational purposes and for applications in nonlinear spectroscopy. We have constructed a Distributed Feedback Dye Laser (DFDL) using interferometric pumping. DFDL works according to the dynamic modulation of the gain medium creating short pulses. Shortening of the pulses, stability, and dynamic range of the DFDL were investigated. Pulses were measured with the help of a photodiode with a 30 picosecond response time. Traces were recorded with a Tektronics DSA73304D (33GHz) digital serial analyser. The gain medium contains an ethanol solution of Rhodamine 590 dye and DODCI saturable absorber. Increasing the concentration of DODCI saturable absorber resulted in significant pulse shortening (150 to 54 picoseconds). Single pulse generation was achieved when the power of the pump laser was adjusted 10 percent above the laser threshold. The central wavelength of the laser pulses was 587 nm. The mathematical modeling, optical layout of the DFDL, and the results of the temporal and spectral characterization of the laser are presented on the poster. The development of the DFDL will lead to an extensive investigation of short pulse dye lasers for educational purposes and for applications in nonlinear spectroscopy. Financial support from University of West Florida is acknowledged.

  17. Laser and spectral characteristics of a DCM-propylene carbonate dye laser system pumped by a XeCl excimer laser

    SciTech Connect

    Shangguan Cheng; Lin Yingyi; Jiang Jinquan; Dou Airon; Wang Yiman; Liu Dianyou; Guo Chu

    1987-12-01

    The energy output and spectral characteristics of a DCM-propylene carbonate dye laser system pumped by a XeCl excimer laser have been measured. The results obtained indicate that DCM-propylene carbonate dye laser system shows a lower energy output and wider frequency-tuning range compared with the case of using dimethylsulfoxide as solvent, which is expected from comparison of the fluorescence parameters of DCM in both solvents.

  18. Flashlamp-pumped pulsed dye laser therapy for poikiloderma of Civatte.

    PubMed

    Wheeland, R G; Applebaum, J

    1990-01-01

    The use of pulsed yellow light from a flash-lamp-pumped pulsed dye laser has provided a successful form of therapy to remove both the telangiectasias and irregular pigmentation associated with poikiloderma of Civatte. The short pulse duration and specificity of the interaction between yellow light and hemoglobin permit this technique to be performed on the thin skin of the neck without textural changes or scarring. Furthermore, use of the large beam diameter of this laser system allows for rapid treatment of large areas in a short period of time. PMID:2299018

  19. Performance of Pyrromethene 580 and 597 in a commercial Nd:YAG-pumped dye-laser system.

    PubMed

    Partridge, W P; Laurendeau, N M; Johnson, C C; Steppel, R N

    1994-10-15

    We report the performance of two new laser dyes, Pyrromethene 580 and 597, in a 10-Hz, Nd:YAG-pumped dye-laser system. These dyes demonstrate broader and more efficient tuning curves compared with those of Rhodamine 590 and 610. Pyrromethene 580 and 597 provide peak conversion efficiencies of 38% at 552 nm and 32% at 571 nm, respectively. Moreover, these new dyes provide conversion efficiencies of 31% near 572.5 nm, a wavelength used for fluorescence studies of NO. This enhanced efficiency should improve the signal-to-noise ratio in linear fluorescence [NO] measurements. PMID:19855604

  20. Oxazine laser dyes

    DOEpatents

    Hammond, Peter R. (Livermore, CA); Field, George F. (Danville, CA)

    1992-01-01

    New oxazine compounds useful as dye laser media in solution, are superiior to prior art materials. The oxazine dyes useful when pumped by the 578.2 nm copper line to operate in the 700-800 nm range are described by formula I ##STR1##

  1. Update on flashlamp pumped pulsed dye laser treatment for port wine stains (capillary malformation) patients

    PubMed Central

    Hsiao, Yen-Chang; Chang, Cheng-Jen

    2011-01-01

    Background and Aims: Currently, the method of choice for the treatment of port-wine stains is laser photocoagulation. Because of evolving treatment options, it is no longer enough for port-wine stains merely to be lightened through laser treatment. The best course of management consists of the most appropriate laser that will produce the most complete clearing of a lesion in the fewest treatment sessions with the least morbidity. The goal is generally accomplished with the use of yellow-light lasers. Materials (Subjects) and Methods: Absorption of laser energy by melanin causes localized heating in the epidermis, which may, if not controlled, produce permanent complications such as hypertrophic scarring or dyspigmentation. Refinements of the results can be achieved by using the flashlamp-pumped pulsed dye laser (FLPDL) in conjunction with the cryogen spray cooling (CSC) system. In our related studies, the infrared thermal image instrument is used for doctors in determining the optimum laser light dosage and preventing the side effects caused by FLPDL. Topic application of angiogenesis inhibitor (Imiquimod) in conjunction with pulsed dye laser treatment for the PWS patients has been assessed for improvement of FLPDL treatment. Results: We present the clinical effect of FLPDL, and the efficacy and safety of cooled laser treatment of PWS birthmarks. Our clinical outcome in the laser treatment of patients with PWS has been achieved to maximize thermal impact on targeted vessels, while minimizing adverse complications. Conclusions: CSC in conjunction with FLPDL can improve the treatment of PWS. The infrared image instrument is helpful for doctors in determining the optimum laser light dosage. Topic application of angiogenesis inhibitor (Imiquimod) in conjunction with laser treatment for the PWS patients is promising in the near future. PMID:24155536

  2. Studies to enhance the beam quality from flashlamp pumped dye lasers

    SciTech Connect

    Titterton, D.H.; Winstanley, P.A.; Finlayson, A.J.; Case, A.D.; Llewelyn, E.S. [DRA Farnborough (United Kingdom)

    1994-12-31

    A number of techniques have been considered for reducing the divergence of the beam of energy generated by a flashlamp pumped dye laser, particularly for those lasers with a high Fresnel number. The principal motivation is to enhance the brightness of such laser beams. The techniques that have been evaluated, or are under active investigation, include: (1) solvent effects; (2) unstable resonators; (3) telescopic resonators; (4) oscillator amplifier configurations; and (5) phase conjugation techniques. Results are presented that show that judicious choice of solvents can give a modest reduction in divergence and improvements of at least a factor two in beam brightness. More sophisticated techniques such as the use of a telescopic resonator can enhance the brightness by a factor in excess of 200. There is scope for further improvement in beam quality by suitable combinations of techniques or materials.

  3. Monolithic dye laser amplifier

    DOEpatents

    Kuklo, T.C.

    1993-03-30

    A fluid dye laser amplifier for amplifying a dye beam by pump beams has a channel structure defining a channel through which a laseable fluid flows and the dye and pump beams pass transversely to one another through a lasing region. The channel structure is formed with two pairs of mutually spaced-apart and mutually confronting glass windows, which are interlocked and make surface-contacts with one another and surround the lasing region. One of the glass window pairs passes the dye beam and the other passes the pump beams therethrough and through the lasing region. Where these glass window pieces make surface-contacts, glue is used to join the pieces together to form a monolithic structure so as to prevent the dye in the fluid passing through the channel from entering the space between the mutually contacting glass window pieces.

  4. Monolithic dye laser amplifier

    DOEpatents

    Kuklo, Thomas C. (Ripon, CA)

    1993-01-01

    A fluid dye laser amplifier for amplifying a dye beam by pump beams has a channel structure defining a channel through which a laseable fluid flows and the dye and pump beams pass transversely to one another through a lasing region. The channel structure is formed with two pairs of mutually spaced-apart and mutually confronting glass windows, which are interlocked and make surface-contacts with one another and surround the lasing region. One of the glass window pairs passes the dye beam and the other passes the pump beams therethrough and through the lasing region. Where these glass window pieces make surface-contacts, glue is used to join the pieces together to form a monolithic structure so as to prevent the dye in the fluid passing through the channel from entering the space between the mutually contacting glass window pieces.

  5. Spectroscopy and laser characteristics of copper-vapor-laser pumped pyrromethene-556 and pyrromethene-567 dye solutions.

    PubMed

    Assor, Y; Burshtein, Z; Rosenwaks, S

    1998-07-20

    We measured the basic optical properties of Pyrromethene-567 (P567) and Pyrromethene-556 (P556) dye solutions that are relevant to their application as dye lasers. The fluorescence spectra of methanol solutions show mirror images in relation to the absorption spectra, with Stokes shifts of 29.5 and 37.5 nm, respectively, for the two dyes. The central fluorescence peaks were at 546 and 535 nm, with widths of ~40 and ~50 nm (FWHM). The quantum yields were 97% ? 5% and 78% ? 5% for P567 and P556, respectively. Fluorescence lifetimes of 6.0 ? 0.2 ns were obtained for both dyes in methanol. Laser action, obtained by pumping with the green emission line (510.6 nm) from a copper-vapor laser, was measured in a Hänsch-type cavity. Tunability ranged from 531 to 590 nm for P567 and from 522 to 590 nm for P556. Lasing thresholds were ~0.27 and ~0.16 mJ/pulse, with 25% and 27% slope efficiencies for P567 and P556, respectively. Spectroscopy and lasing were studied in other solvents as well. PMID:18285957

  6. Multi-terrawatt, 100 fsec laser system using flashlamp-pumped, dye- converted Ti:Sapphire as an amplifier

    SciTech Connect

    White, W.E.; Reitize, D.H.; Price, D.F.; Shepherd, R.L.; Bonlie, J.D.; Hunter, J.R.; Patterson, F.G. [Lawrence Livermore National Lab., CA (United States); Perressini, D.L. [Union Carbide Corp., Washougal, WA (United States)

    1993-04-14

    We report on amplification of 100 fsec laser pulses to 250 mJ using flashlamp-pumped, dye converted Ti:Sapphire. The resulting 5 Hz beam is focused to irradiances in excess of 5 {times} 10{sup 18} W/cm{sup 2}.

  7. The use of caffeine as a liquid filter in coaxial flashlamp pumped dye lasers

    NASA Astrophysics Data System (ADS)

    Calkins, John; Colley, Ed; Hazle, John

    1982-07-01

    Problems of cooling and preserving laser dyes can be solved by adding caffeine or other suitable filter materials to the cooling water in coaxial systems. Systems using dissolved filter chemicals are cheap, versatile and assist in heat removal from coaxial type dye lasers.

  8. High efficiency picosecond pulse generation in the 675-930 nm region from a dye laser synchronously pumped by an argon-ion laser. Technical report

    SciTech Connect

    Bado, P.; Dupuy, C.; Wilson, K.R.; Boggy, R.; Bowen, J.

    1983-04-01

    Picosecond pulses tunable from 675 to 930 micrometers have been obtained from a dye-laser synchronously pumped at 514.5 micrometers by a mode-locked Argon-ion laser. Peak energy conversion efficiencies between 10% and 29% are observed with pulse durations between 1.7 ps and 16 ps as measured by autocorrelation.

  9. Dye laser pumped by Nd:YAG laser pulses frequency doubled in a glass optical fiber

    Microsoft Academic Search

    U. Österberg; W. Margulis

    1986-01-01

    Efficient frequency doubling of a cw Q-italic-switched and mode-locked Nd:YAG laser has been observed in commercial single-mode optical glass fibers. Pulses of duration --55 psec and intensities as high as --0.55 kW were produced at 0.53 ..mu..m. The maximum peak power-conversion efficiency measured was --3%. The frequency-doubled light generated in the glass fibers was sufficient to pump a commercial Rh6G

  10. Laser dye technology

    SciTech Connect

    Hammond, P R

    1999-09-01

    The author has worked with laser dyes for a number of years. A first interest was in the Navy blue-green program where a flashlamp pumped dye laser was used as an underwater communication and detection device. It made use of the optical window of sea-water--blue for deep ocean, green for coastal water. A major activity however has been with the Atomic Vapor Laser Isotope Separation Program (AVLIS) at the Lawrence Livermore National Laboratory. The aim here has been enriching isotopes for the nuclear fuel cycle. The tunability of the dye laser is utilized to selectively excite one isotope in uranium vapor, and this isotope is collected electrostatically as shown in Figure 1. The interests in the AVLIS program have been in the near ultra-violet, violet, red and deep-red.

  11. 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.

  12. Photodynamic effect of copper-vapor pumped-dye laser, He-Ne laser, and noncoherent red light to the liver in normal mice

    Microsoft Academic Search

    Chuannong Zhou; Xuyan Song; Jinsheng Deng; Junlin Liang; Hua Zhang; Wenjia Huang; Tao Liu; Xian-Wen Ha

    1993-01-01

    A quantitative comparison of the photodynamic effect of pulsed (copper vapor-pumped dye laser), continuous-wave laser (He-Ne laser), and non-coherent red light (filtered from a halogen lamp) to the liver in normal mice has been carried out. The mice (each group containing 18 - 20 mice) received hematoporphyrin derivative in a dose of 10 mg\\/kg iv 24 hours prior to light

  13. Dye system for dye laser applications

    DOEpatents

    Hammond, Peter R. (Livermore, CA)

    1991-01-01

    A dye of the DCM family, [2-methyl-6-[2-(1,2,3,4-tetrahydro-1-methyl-6-quinolinyl)ethenyl]-4H-pyran -4-ylidene]-propanedinitrile, dissolved in 2-phenoxyethanol, is non-mutagenic, stable and efficient, particularly in a pumped continuous wave laser system.

  14. Optofluidic dye lasers

    Microsoft Academic Search

    Zhenyu Li; Demetri Psaltis

    2008-01-01

    Optofluidic dye lasers are microfabricated liquid dye lasers enabled by the microfluidics technology. The integration of dye\\u000a lasers with microfluidics not only facilitates the implementation of complete “lab-on-a-chip” systems, but also allows the\\u000a dynamical control of the laser properties which is not achievable with solid-state optical components. We review the recent\\u000a demonstrations of on-chip liquid dye lasers and some of

  15. Theory of pulsed dye lasers including dye-molecule rotational relaxation

    Microsoft Academic Search

    Roger A. Haas; Mark D. Rotter

    1991-01-01

    In this paper a phenomenological semiclassical theory of pulsed-laser-pumped dye-laser light amplifiers is presented. The theory accounts for the broadband radiation absorption and emission characteristics of dye molecules in liquid solvents. Dye-molecule fluorescence, vibrational, rotational, and electric polarization relaxation processes are represented by phenomenological relaxation rates. In general, it is found that due to dye-molecule rotational relaxation the laser-pumped dye

  16. The generation of quasi-continuous, tunable 200 nm excitation using the MHz amplified synchronously pumped dye laser: Application to UV resonance raman spectroscopy

    Microsoft Academic Search

    Terry L. Gustafson

    1988-01-01

    We demonstrate the generation of quasi-continuous, tunable excitation in the 200 nm region by sum frequency mixing the fundamental and second harmonic from the MHz amplified synchronously pumped dye laser in beta-BaB2O4. We use the output as the excitation source for ultraviolet resonance Raman spectroscopy.

  17. Levitated droplet dye laser

    E-print Network

    Azzouz, H; Balslev, S; Johansson, J; Mortensen, N A; Nilsson, S; Kristensen, A

    2006-01-01

    We present the first observation, to our knowledge, of lasing from a levitated, dye droplet. The levitated droplets are created by computer controlled pico-liter dispensing into one of the nodes of a standing ultrasonic wave (100 kHz), where the droplet is trapped. The free hanging droplet forms a high quality optical resonator. Our 750 nL lasing droplets consist of Rhodamine 6G dissolved in ethylene glycol, at a concentration of 0.02 M. The droplets are optically pumped at 532 nm light from a pulsed, frequency doubled Nd:YAG laser, and the dye laser emission is analyzed by a fixed grating spectrometer. With this setup we have achieved reproducible lasing spectra in the visible wavelength range from 610 nm to 650 nm. The levitated droplet technique has previously successfully been applied for a variety of bio-analytical applications at single cell level. In combination with the lasing droplets, the capability of this high precision setup has potential applications within highly sensitive intra-cavity absorban...

  18. Levitated droplet dye laser

    NASA Astrophysics Data System (ADS)

    Azzouz, H.; Alkhafadiji, L.; Balslev, S.; Johansson, J.; Mortensen, N. A.; Nilsson, S.; Kristensen, A.

    2006-05-01

    We present the first observation, to our knowledge, of lasing from a levitated, dye droplet. The levitated droplets are created by computer controlled pico-liter dispensing into one of the nodes of a standing ultrasonic wave (100 kHz), where the droplet is trapped. The free hanging droplet forms a high quality optical resonator. Our 750 nL lasing droplets consist of Rhodamine 6G dissolved in ethylene glycol, at a concentration of 0.02 M. The droplets are optically pumped at 532 nm light from a pulsed, frequency doubled Nd:YAG laser, and the dye laser emission is analyzed by a fixed grating spectrometer. With this setup we have achieved reproducible lasing spectra in the visible wavelength range from 610 nm to 650 nm. The levitated droplet technique has previously successfully been applied for a variety of bio-analytical applications at single cell level. In combination with the lasing droplets, the capability of this high precision setup has potential applications within highly sensitive intra-cavity absorbance detection.

  19. Characteristics of a broadband dye laser using Pyrromethene and Rhodamine dyes.

    PubMed

    Tedder, Sarah A; Wheeler, Jeffrey L; Danehy, Paul M

    2011-02-20

    A broadband dye laser pumped by a frequency-doubled Nd:YAG laser with a full width at half-maximum from 592 to 610?nm was created for the use in a dual-pump broadband coherent anti-Stokes Raman spectroscopy (CARS) system called width increased dual-pump enhanced CARS (WIDECARS). The desired broadband dye laser was generated with a mixture of Pyrromethene dyes as an oscillator gain medium and a spectral selective optic in the oscillator cavity. A mixture of Rhodamine dyes was used in the amplifier dye cell. To create this laser, a study was performed to characterize the spectral behavior of broadband dye lasers created with Rhodamine dyes 590, 610, and 640 and Pyrromethene dyes 597 and 650, as well as mixtures of these dyes. PMID:21343970

  20. 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.

  1. Optofluidic ring resonator dye lasers

    NASA Astrophysics Data System (ADS)

    Sun, Yuze; Suter, Jonathan D.; Fan, Xudong

    2010-02-01

    We overview the recent progress on optofluidic ring resonator (OFRR) dye lasers developed in our research group. The fluidics and laser cavity design can be divided into three categories: capillary optofluidic ring resonator (COFRR), integrated cylindrical optofluidic ring resonator (ICOFRR), and coupled optofluidic ring resonator (CpOFRR). The COFRR dye laser is based on a micro-sized glass capillary with a wall thickness of a few micrometers. The capillary circular cross-section forms the ring resonator and supports the whispering gallery modes (WGMs) that interact evanescently with the gain medium in the core. The laser cavity structure is versatile to adapt to the gain medium of any refractive index. Owing to the high Q-factor (>109), the lasing threshold of 25 nJ/mm2 is achieved. Besides directly pump the dye molecules, lasing through fluorescence resonance energy transfer (FRET) between the donor and acceptor dye molecules is also studied in COFRR laser. The energy transfer process can be further controlled by designed DNA scaffold labeled with donor/acceptor molecules. The ICOFRR dye laser is based on a cylindrical ring resonator fused onto the inner surface of a thick walled glass capillary. The structure has robust mechanical strength to sustain rapid gain medium circulation. The CpOFRR utilizes a cylindrical ring resonator fused on the inner surface of the COFRR capillary. Since the capillary wall is thin, the individual WGMs of the cylindrical ring resonator and the COFRR couples strongly and forms Vernier effect, which provides a way to generate a single mode dye laser.

  2. Characterisation Of The Light Pulses Of A Cavity Dumped Dye Laser Pumped By A Cw Mode-Locked And Q-Switched Nd:YAG Laser

    NASA Astrophysics Data System (ADS)

    Geist, P.; Heisel, F.; Martz, A.; Miehe, J. A.; Miller, R. J.

    1985-02-01

    The temporal characteristics of the frequency doubled pulses of a continuous-wave ,Iode-locked or mode-locked and Q-switched Nd:YAG laser have been investigated by means of a streak camera operating in synchroscan (Fig. 1) or triggered mode (Fig. 3). The second harmonic of the cw mode-locked Nd:YAG laser using a KTP crystal, has resulted in 532 nm optical pulses of 60 ps duration with a conversion efficiency of 12 % (Fig. 2A). The frequency doubled output of the continuously pumped acoustooptically Q-switched and mode-locked Nd:YAG laser showed pulses of 80 ps width (Fig. 2B). Stable, reproducible and single pulses at 560 nm of 10 laJ energy and 30 ps duration have been obtained in a synchronously pumped and cavity dumped dye laser (Fig. 4). The cavity dumper consisted of a Pockels cell with avalanche transistor driver. Single shot (Figs. 5A,B and 6A,B) and 500-800 Hz repetition rate (Figs. 5C and 6C) measurements have been carried out by means of a triggered streak ca-mera. Moreover, interesting information of the pulse formation in the cavity has been obtained by triggering the dumper at the beginning (Fig. 5) and at the end (Fig. 6) of the pulse train : for the last condition it appeared short and symmetrical pulses (FWHM 25 ps).

  3. Fiber optics interface for a dye laser oscillator and method

    DOEpatents

    Johnson, Steve A. (Tracy, CA); Seppala, Lynn G. (Pleasanton, CA)

    1986-01-01

    A dye laser oscillator in which one light beam is used to pump a continuous tream of dye within a cooperating dye chamber for producing a second, different beam is generally disclosed herein along with a specific arrangement including an optical fiber and a fiber optics interface for directing the pumping beam into the dye chamber. The specific fiber optics interface illustrated includes three cooperating lenses which together image one particular dimension of the pumping beam into the dye chamber from the output end of the optical fiber in order to insure that the dye chamber is properly illuminated by the pumping beam.

  4. Fiber optics interface for a dye laser oscillator and method

    DOEpatents

    Johnson, S.A.; Seppala, L.G.

    1984-06-13

    A dye laser oscillator in which one light beam is used to pump a continuous stream of dye within a cooperating dye chamber for producing a second, different beam is generally disclosed herein along with a specific arrangement including an optical fiber and a fiber optics interface for directing the pumping beam into the dye chamber. The specific fiber optics interface illustrated includes three cooperating lenses which together image one particular dimension of the pumping beam into the dye chamber from the output end of the optical fiber in order to insure that the dye chamber is properly illuminated by the pumping beam.

  5. Medium performance effect on the high output energy from a xenon lamp-pumped pyrromethene-567 solid-state dye laser

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Chen, De-Ying; Fan, Rong-Wei; He, Wei-Ming

    2012-04-01

    In order to obtain a high output energy from a xenon lamp-pumped solid-state dye laser, homogeneities of laser mediums and flatnesses of medium faces with different processing treatments are discussed in the paper. The mediums without aging treatment, which are prepared by using a prepolymer process and have diamond-machined end faces to produce the required optical finish, give a highest laser output of 281.9 mJ with 0.215% slope efficiency at 2.0 × 10-4 mol/L. The best medium lifetime is 21 shots to 50% of original output equating 74.6 kJ/liter.

  6. Characteristics of a Broadband Dye Laser Using Pyrromethene and Rhodamine Dyes

    NASA Technical Reports Server (NTRS)

    Tedder, Sarah A.; Danehy, Paul M.; Wheeler, Jeffrey L.

    2011-01-01

    A broadband dye laser pumped by a frequency-doubled Nd:YAG laser with a full-width half-maximum (FWHM) from 592 to 610 nm was created for the use in a dual-pump broadband CARS system called WIDECARS. The desired broadband dye laser was generated with a mixture of Pyrromethene dyes as an oscillator gain medium and a spectral selective optic in the oscillator cavity. A mixture of Rhodamine dyes were used in the amplifier dye cell. To create this laser a study was performed to characterize the spectral behavior of broadband dye lasers created with Rhodamine dyes 590, 610, and 640, Pyrromethene dyes 597 and 650 as well as mixture of these dyes.

  7. 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.

  8. Solid state dye laser for medical applications

    NASA Astrophysics Data System (ADS)

    Aldag, Henry R.

    1994-06-01

    The development of solid state dye lasers could lead to a major breakthrough in the cost and compactness of a medical device. Advantages include: elimination of the flow system for the gain medium; ease with which to implement wavelength agility or the replacement of a degraded rod or sheet; and toxicity and flammability become a non-issue. Dye lasers have played a role in cardiology, dermatology, and urology. Of these cardiology is of interest to Palomar. The Palomar Model 3010 flashlamp-pumped dye laser medical device was used during phase 1 FDA clinical trials to break-up blood clots that cause heart attacks, a process known as coronary laser thrombolysis. It is the objective of this research and development effort to produce solid matrix lasers that will replace liquid dye lasers in these medical specialties.

  9. Dye laser traveling wave amplifier

    NASA Technical Reports Server (NTRS)

    Davidson, F.; Hohman, J.

    1985-01-01

    Injection locking was applied to a cavity-dumped coaxial flashlamp pumped dye laser in an effort to obtain nanosecond duration pulses which have both high energy and narrow-linewidth. In the absence of an injected laser pulse, the cavity-dumped dye laser was capable of generating high energy (approx. 60mJ) nanosecond duration output pulses. These pulses, however, had a fixed center wavelength and were extremely broadband (approx. 6nm FWHM). Experimental investigations were performed to determine if the spectral properties of these outputs could be improved through the use of injection-locking techniques. A parametric study to determine the specific conditions under which the laser could be injection-locked was also carried out. Significant linewidth reduction to 0.0015nm) of the outputs was obtained through injection-locking but only at wavelengths near the peak lasing wavelength of the dye. It was found, however; that by inserting weakly dispersive tuning elements in the laser cavity, these narrow-linewidth outputs could be obtained over a wide (24nm) tuning range. Since the tuning elements had low insertion losses, the tunability of the output was obtained without sacrificing output pulse energy.

  10. Theory of pulsed dye lasers including dye-molecule rotational relaxation

    SciTech Connect

    Haas, R.A.; Rotter, M.D. (Department of Applied Science, University of California, Davis-Livermore, L-794, P.O. Box 808, Livermore, California 94550 (US) Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550)

    1991-02-01

    In this paper a phenomenological semiclassical theory of pulsed-laser-pumped dye-laser light amplifiers is presented. The theory accounts for the broadband radiation absorption and emission characteristics of dye molecules in liquid solvents. Dye-molecule fluorescence, vibrational, rotational, and electric polarization relaxation processes are represented by phenomenological relaxation rates. In general, it is found that due to dye-molecule rotational relaxation the laser-pumped dye medium is optically anisotropic. The pump- and dye-laser beams propagate through the dye medium as essentially transverse electromagnetic waves whose amplitude and polarization state changes. The theory is applicable to pulse durations {tau}{approx lt}10--100 ns including the ultrashort pulse regime. The regime {tau}{approx gt}1 ps in which the pump- and dye-laser pulse lengths are long compared to the dye-molecule vibrational and electric polarization relaxation times is considered in detail. Amplification of partially polarized quasimonochromatic light is described by a self-consistent set of equations for the components of the pump- and dye-laser light coherency matrices and the orientation populations of the lowest vibronic levels of the dye molecule's {ital S}{sub 0} and {ital S}{sub 1} electronic states.

  11. Dye laser tuner

    SciTech Connect

    Arthurs, E.G.; Purdie, A.F.

    1980-11-11

    A laser of the kind in which the lasing medium is a free flowing dye stream incorporates a means of tuning the output wave length of the laser, this means being in the form of a wedged birefringent plate which is driven in a linear mode by a linear translator so that the thickness of the birefringent plate traversed by the intracavity beam of laser light may be varied.

  12. Continuous-wave organic dye lasers and methods

    DOEpatents

    Shapira, Ofer; Chua, Song-Liang; Zhen, Bo; Lee, Jeongwon; Soljacic, Marin

    2014-09-16

    An organic dye laser produces a continuous-wave (cw) output without any moving parts (e.g., without using flowing dye streams or spinning discs of solid-state dye media to prevent photobleaching) and with a pump beam that is stationary with respect to the organic dye medium. The laser's resonant cavity, organic dye medium, and pump beam are configured to excite a lasing transition over a time scale longer than the associated decay lifetimes in the organic dye medium without photobleaching the organic dye medium. Because the organic dye medium does not photobleach when operating in this manner, it may be pumped continuously so as to emit a cw output beam. In some examples, operation in this manner lowers the lasing threshold (e.g., to only a few Watts per square centimeter), thereby facilitating electrical pumping for cw operation.

  13. Characteristics of xenon-lamp pumped pyrromethene 567-doped dye laser based on polymethylmethacrylater

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Chen, De-Ying; Xia, Yuan-Qin; Fan, Rong-Wei; He, Wei-Ming

    2012-01-01

    The solid-state medium containing pyrromethene 567 (PM567) in a polymethylmethacrylate polymer host is shown to lase under the flash lamp excitation. The experimental setup is an ordinary industrial product without special design. The bulk transmission losses, the output energy, and the other lasing properties are compared. The medium with the lowest transmission loss, measured to be 0.392 %/cm at 633 nm, gives a laser output of 130 mJ with a slope efficiency of 0.082%.

  14. 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.

  15. Treatment of Port-Wine Stains with Flash Lamp Pumped Pulsed Dye Laser on Indian Skin: A Six Year Study

    PubMed Central

    Thajudheen, Chandroth Ponnambath; Jyothy, Kannangath; Priyadarshini, Arul

    2014-01-01

    Context: Port-wine stain (PWS) is one of the commonly encountered congenital cutaneous vascular lesions, with an equal sex distribution. Pulsed dye lasers (PDL) have revolutionized the treatment of both congential and acquired cutaneous vascular lesions. The pulsed dye lasers owing to its superior efficacy and safety profile have become the gold standard for the management of port-wine stains. Aims: To evaluate the efficacy and side effects of pulsed dye laser for the management of Port-wine stain on Indian skin. Materials and Methods: Seventy five patients of Fitzpatrick skin types IV&V with PWS underwent multiple treatments with PDL (V beam-Candela) over a period of six years at monthly intervals. Laser parameters were wavelength 595nm, spot sizes 7-10mm, fluence 6-12 j/cm2, pulse duration 0.45-10ms, along with cryogen cooling. Serial photographs were taken before and after every session. Clinical improvement scores of comparable photographs using a quartile grading (o=<20%, 1=21-40%, 2=41-60%, 3=61-80%, 4=>80%) were judged independently by two dermatologists after the series of treatment. Minimum number of treatments was 6 and maximum 17. They were followed up at six monthly intervals to observe re darkening of PWS. Results: No patient showed total clearance.Grade3 improvement was observed in 70 % of children and 50% of adults after 8-10 sessions. Children showed better and faster response than adults. Thirty percent of patients developed post inflammatory hyper pigmentation which resolved over a period of six to eight weeks. Two patients had superficial scarring due to stacking of pulses. None of the patients showed re darkening of PWS till now. Conclusion: Pulsed dye laser is an effective and safe treatment for port-wine stain in Indian skin. PMID:24761097

  16. Water soluble laser dyes

    DOEpatents

    Hammond, Peter R. (Livermore, CA); Feeman, James F. (Wyomissing, PA); Field, George F. (Santa Ana, CA)

    1998-01-01

    Novel water soluble dyes of the formula I are provided ##STR1## wherein R.sup.1 and R.sup.4 are alkyl of 1 to 4 carbon atoms or hydrogen; or R.sup.1 -R.sup.2 or R.sup.2 -R.sup.4 form part of aliphatic heterocyclic rings; R.sup.2 is hydrogen or joined with R.sup.1 or R.sup.4 as described above; R.sup.3 is --(CH.sub.2).sub.m --SO.sub.3.sup.-, where m is 1 to 6; X is N, CH or ##STR2## where Y is 2 --SO.sub.3.sup.- ; Z is 3, 4, 5 or 6 --SO.sub.3.sup.-. The novel dyes are particularly useful as the active media in water solution dye lasers.

  17. Water soluble laser dyes

    DOEpatents

    Hammond, P.R.; Feeman, J.F.; Field, G.F.

    1998-08-11

    Novel water soluble dyes of the formula 1 are provided by the formula described in the paper wherein R{sup 1} and R{sup 4} are alkyl of 1 to 4 carbon atoms or hydrogen; or R{sup 1}--R{sup 2} or R{sup 2}--R{sup 4} form part of aliphatic heterocyclic rings; R{sup 2} is hydrogen or joined with R{sup 1} or R{sup 4} as described above; R{sup 3} is --(CH{sub 2}){sub m}--SO{sub 3}{sup {minus}}, where m is 1 to 6; X is N, CH or formula 2 given in paper where Y is 2 --SO{sub 3}{sup {minus}} ; Z is 3, 4, 5 or 6 --SO{sub 3}{sup {minus}}. The novel dyes are particularly useful as the active media in water solution dye lasers.

  18. Nanoimprinted polymer photonic crystal dye lasers

    NASA Astrophysics Data System (ADS)

    Christiansen, Mads B.; Smith, Cameron L. C.; Buss, Thomas; Xiao, Sanshui; Mortensen, Niels A.; Kristensen, Anders

    2010-05-01

    Optically pumped polymer photonic crystal band-edge dye lasers are presented. The photonic crystal is a rectangular lattice providing laser feedback as well as an optical resonance for the pump light. The lasers are defined in a thin film of photodefinable Ormocore hybrid polymer, doped with the laser dye Pyrromethene 597. A compact frequency doubled Nd:YAG laser (352 nm, 5 ns pulses) is used to pump the lasers from above the chip. The laser devices are 450 nm thick slab waveguides with a rectangular lattice of 100 nm deep air holes imprinted into the surface. The 2-dimensional rectangular lattice is described by two orthogonal unit vectors of length a and b, defining the ?P and ?X directions. The frequency of the laser can be tuned via the lattice constant a (187 nm - 215 nm) while pump light is resonantly coupled into the laser from an angle (?) depending on the lattice constant b (355 nm). The lasers are fabricated in parallel on a 10 cm diameter wafer by combined nanoimprint and photolithography (CNP). CNP relies on a UV transparent quartz nanoimprint stamp with an integrated metal shadow mask. In the CNP process the photonic crystal is formed by mechanical deformation (imprinting) while the larger features are defined by UV exposure through the combined mask/mold.

  19. Laser properties and photostabilities of laser dyes doped in ORMOSILs

    NASA Astrophysics Data System (ADS)

    Yang, Yu; Wang, Minquan; Qian, Guodong; Wang, Zhiyu; Fan, Xianping

    2004-01-01

    Laser dyes such as rhodamine B, rhodamine 6G, pyrromethene 567, perylene orange and perylene red were doped into GPTMS-, MTES- and VTES-derived organically modified silicates (ORMOSILs) by sol-gel process. A longitudinal pumped solid-state dye laser was established with a Q-switched Nd:YAG laser source. The lifetimes of these dyes in various ORMOSILs were investigated by using such an experimental setup at a pump repetition rate of 2 Hz and pump intensity of 0.1 or 1.4 J/cm 2. The lifetime of 60 000 pulses, 50 GJ/mol in normalized photostability, was obtained for the pyrromethene 567 doped in MTES-derived ORMOSIL with the net sample thickness of 4 mm when its output energy declined to 50% of its initial value. The slope efficiencies of pyrromethene 567 and perylene orange in various host media were also measured.

  20. Solid state dye lasers with scattering feedback

    NASA Astrophysics Data System (ADS)

    Costela, A.; Cerdán, L.; García-Moreno, I.

    2013-11-01

    Over the last decade, significant advances have been made toward the development of practical, tunable solid state dye lasers, which resulted in improved lasing efficiency with reduced dye photodegradation. To achieve this goal, a “chemical” approach was followed, where attention was focused onto the particular dye/host interaction and compatibility, specifically choosing already existing hosts for a given dye, synthesizing new dyes and/or matrices, or chemically modifying existing ones. Nevertheless, this approach was limited by a single fact learnt from the experience: there is no universal matrix which optimizes the efficiency and photostability of all dyes. This limitation could be overcome by following a “physical” approach, where the emission properties of the active medium are tailored by means of physical and structural modifications of the dye host. Following this approach, in this paper recent theoretical and experimental work is reviewed where it is demonstrated that following a simultaneous “physical” and “chemical” approach to tailor the emission properties of the host materials for solid state dye lasers, may lead, under specific circumstances, to the improvement of both the laser efficiency and photostability. In particular, it is demonstrated that optical scattering is not always detrimental either to conventional bulk lasers (laser rods or colloidal suspensions) or to integrated devices, but may give place, on the contrary, to dramatic improvements in the laser operation of organic (hybrid) laser rods, and to alternative ways of obtaining laser light from integrated devices based on the phenomenon of coherent random lasing, where feedback is provided by light scattering in an appropriate medium, without the need to manufacture complex periodic structures in the substrate. The processing and pumping flexibility of these materials, together with their low cost and capability of efficient emission across the whole visible spectrum makes them very attractive for the fabrication and development of coherent light sources suitable for integration in optoelectronic and disposable spectroscopic and sensing devices.

  1. Statistical properties of pulsed dye laser radiation

    NASA Astrophysics Data System (ADS)

    Berik, E.; Davidenko, V.

    1988-06-01

    Single-shot spectral measurements of the radiation of an excimer-laser-pumped dye laser were performed with a high-resolution multichannel recording system in order to determine the influence of mode fluctuations and spectral instabilities of the cavity on an average laser linewidth. It is shown for a 3-15X10 -3nm linewidth, which is typical of commercial lasers in multimode lasing regime, that the standard deviation of the laser linewidth makes up 15 percent of the average amount. The conditions were determined under which the contribution of spectral instabilities of the cavity transmission band becomes essential.

  2. Partially Pumped Random Lasers

    NASA Astrophysics Data System (ADS)

    Andreasen, Jonathan; Bachelard, Nicolas; Bhaktha, Shivakiran B. N.; Cao, Hui; Sebbah, Patrick; Vanneste, Christian

    2014-01-01

    Conventional lasers consist of two components: a gain material that is pumped in order to provide amplification of light and a cavity to provide feedback. Random lasers replace the traditional laser cavity with a random, multiple-scattering medium. This can give rise to complex lasing behavior, such as unpredictable multidirectional and multifrequency output. Controlling these systems has proved difficult and, until now, has consisted of material and structural manipulations. In random lasers, the most common pumping mechanism is an optical field, which can be applied uniformly or partially across the scattering medium. Partial pumping, referring to the restricted spatial extent of the pump applied to the gain material, is therefore quite ubiquitous in such systems. In contrast to conventional lasers, however, the impact of partial pumping can be significant in random lasers as a subset of the scattering medium is probed. In this review, we discuss state-of-the-art investigations of partially pumped random lasers. Numerical and experimental investigations of how even a simple spot profile of the pump can dramatically alter random laser output are presented. First, the simple case of partial pumping in strongly scattering systems where laser modes are spatially confined is described. Then the most common but more difficult case of weakly scattering random lasers is considered. Here, modes are spatially extended, forcing greater mode interaction and making the random laser output more difficult to predict. Finally, we review recent works that show how the pumping degree of freedom allows a general increase in control over random lasers.

  3. Diode pumped alkali lasers

    Microsoft Academic Search

    B. V. Zhdanov; R. J. Knize

    2011-01-01

    Diode pumped alkali lasers attract growing attention during the past several years because they have demonstrated potential to compete and, possibly, replace the best existing high power laser systems. In spite of the fact that an optically pumped alkali (potassium) vapor laser was first proposed by A.L. Schawlow and C.H. Townes in 1958, the intensive research and development of alkali

  4. CW laser pumped emerald laser

    Microsoft Academic Search

    M. L. Shand; S. T. Lai

    1984-01-01

    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

  5. 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.

  6. CW laser pumped emerald laser

    NASA Astrophysics Data System (ADS)

    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.

  7. High efficiency dye laser with low fluorescence yield pyrromethene dyes: experimental and theoretical studies

    NASA Astrophysics Data System (ADS)

    Jagtap, K. K.; Maity, D. K.; Ray, A. K.; Dasgupta, K.; Ghosh, S. K.

    2011-06-01

    A combined experimental and theoretical study of the photo-physical, laser properties and molecular structures of three relatively recent Pyrromethene (PM) class dyes, PM597, PM580 and PM567, have been carried out. Laser characteristics of these three PM dyes were compared with three other widely used Rhodamine (RH) class dyes, RH6G, RHB and KRS, using a narrow-band dye laser setup, transversely pumped by the second harmonic (532 nm) of a Q-switched Nd-YAG laser. In addition to generating comparative data of these dyes for optimal use in dye lasers, we observed that unlike the RH dyes, the PM dyes show high efficiencies and wide tunability, despite the low fluorescence yield and high rate of non-radiative decay. Particularly, PM597 dye, in spite of a very low quantum yield of fluorescence (?=0.42), high non-radiative decay rate, and a large distortion from planarity in its excited state, when used in a laser cavity it exhibited similar laser efficiency and a beneficially wider tuning curve in comparison to other two PM dyes. Theoretical studies were carried out applying density functional theory and time-dependent density functional theory (DFT/TDDFT) to obtain new information on ground and the first excited state geometrical parameters of the PM dyes. Good correlation between calculated molecular properties and experimental results was observed for the evolution of the longest wavelength absorption maximum.

  8. Bichromatic emission in a ring dye laser

    NASA Technical Reports Server (NTRS)

    Lawandy, N. M.; Sohrab Afzal, R.; Rabinovich, W. S.

    1987-01-01

    An experimental study of a high-Q Rhodamine 6G ring dye laser has been performed, and bichromatic emission (BE) with wavelength spacings as large as 110 A when the laser operated bidirectionally has been measured. The BE vanished at all excitations when the laser was forced into unidirectional operation using a Faraday isolator. However, when a weak reflected beam was allowed to make a single pass in the direction opposite to that allowed by the Faraday device, BE is recovered at the higher pump powers.

  9. Optically pumped alkali lasers

    Microsoft Academic Search

    Boris V. Zhdanov; Thomas Ehrenreich; Randall J. Knize

    2007-01-01

    Optically pumped alkali vapor lasers have been developed during last several years. Efficient operation of Cesium, Rubidium and Potassium vapor lasers has been demonstrated. Laser slope efficiencies higher than 80% have been achieved. In this paper we present the latest achievements in this field, discuss the main directions and problems in high power alkali lasers development and possible solutions of

  10. A tunable dual frequency dye laser - dual frequency oscillator design

    NASA Technical Reports Server (NTRS)

    Abury, Y.

    1983-01-01

    The pulsed dye laser offers a tunable oscillator, followed by three amplifiers. It is pumped by a dual frequency Nd:YAG laser. Tuning and spectral width are controlled by a holographic network connected to a high power telescope. The modified two wavelength dye laser allows for absorption lidar techniques for remote sensing of the atmosphere. Line switching is achieved by electrooptical commutation. A feasibility experiment was performed with the original oscillator. A model was then built, and tested with different dyes. After a few modifications were made to improve the conversion efficiency, this oscillator was inserted in the laser to check whether the amplifier stages were correctly adjusted.

  11. Single dye molecule laser via energy transfer mechanism

    NASA Astrophysics Data System (ADS)

    Shan, Guangcun; Huang, Wei

    2008-11-01

    Motivated by the recent progresses in one-atom laser and single-molecule manipulation, this work presents the model and simulations of a single dye molecule laser device, which consists of a single dye molecule as an acceptor in a microcavity pumped by multiple donors via the intermolecular resonance energy transfer mechanism. The photon intensity is calculated at the emission peaks of donor and acceptor dyes for different pump rates and donor numbers. Finally, it is demonstrated that stimulated emission gains a distinct advantage over spontaneous emission under appropriate conditions. This work would have many important applications in a wide range of fields from physics and chemistry to nanotechnology in future.

  12. Solar pumped laser

    NASA Technical Reports Server (NTRS)

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

    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.

  13. Fusion reactor pumped laser

    DOEpatents

    Jassby, Daniel L. (Princeton, NJ)

    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.

  14. Study of excitation transfer in a flowing helium afterglow pumped with a tuneable dye laser. II - Measurement of the rate coefficient for the rotational relaxation of He2/3p 3Pi-g/.

    NASA Technical Reports Server (NTRS)

    Collins, C. B.; Johnson, B. W.

    1972-01-01

    The results of the use of a fast-transient fluorescence technique in the examination of rotational relaxation caused by collisions with neutral helium atoms are discussed. Details regarding the production and detection of reacting species are considered, together with the analytical method used. A dye laser system with 4-methylcoumarin producing a pumping flux in the 4650 A region was employed in the investigations.

  15. High-Intensity Coherent Vacuum Ultraviolet Source Using Unfocussed Commercial Dye Lasers

    E-print Network

    Davis, H. Floyd

    1 High-Intensity Coherent Vacuum Ultraviolet Source Using Unfocussed Commercial Dye Lasers Daniel R Intruments Using two or three commercial pulsed nanosecond dye lasers pumped by a single 30 Hz Nd:YAG laser four-wave mixing of collimated (unfocussed) laser beams in mercury (Hg) vapor. Phase matching

  16. Effect of emission wavelength on photo-stability of laser dye: experimental and theoretical study

    NASA Astrophysics Data System (ADS)

    Jagtap, Krishna; Ray, A. K.; Sinha, S.; Dasgupta, K.; Sarkar, S. K.

    2012-09-01

    Photo-stability of laser dyes has been an important consideration for dye lasers. In this work, photo-stability of dye and its effect has been investigated as a function of dye laser wavelengths rather than commonly studied photo-chemical degradation pathways upon excitation with pump laser. Here, we report a significant improvement in photo-stability of the liquid dye laser at peak emission wavelength compared to edge wavelengths of the dye gain curve, which was related with an increase in rate of stimulated emission of dye at peak wavelength. Thus, high laser efficiency harmonizes to high photo-stability of the dye at peak wavelength which is useful for the applications of dye lasers. As a representative case, the photo-stability rates of pyrromethene 567 (PM567) dye at different laser emission wavelengths were studied using a 10-Hz Nd-YAG (532 nm) laser-pumped dye laser set-up under lasing and non-lasing conditions. Deterioration of dye laser efficiency on account of photo-degradation of dye molecules was theoretically simulated using a time-dependent rate equation model, which has been found to be in good agreement with the experimental observations.

  17. Study of the effect of the keep-alive discharge on the efficiency of flashlamp-pumped repetitively pulsed dye lasers

    SciTech Connect

    Dzyubenko, M.I.; Maslov, V.V.; Pelipenko, V.P.; Shevchenko, V.V. [Institute of Radiophysics and Electronics, Khar`kov (Russian Federation)

    1995-04-01

    The effect of operating conditions of flashlamps on oscillation characteristics of dye lasers is investigated. It is shown that considerable improvement of the oscillation efficiency in a laser using an auxiliary discharge results from increased light output of the flashlamps due to the increased temperature of the main discharge.

  18. Explosively pumped laser light

    DOEpatents

    Piltch, Martin S. (Los Alamos, NM); Michelotti, Roy A. (Los Alamos, NM)

    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.

  19. Analysis of a dye-laser model including quantum noise

    SciTech Connect

    Aguado, M.; San Miguel, M.

    1988-01-15

    An analytical study of a dye-laser model which includes quantum white noise and nonwhite pump fluctuations is presented. The extension of an earlier approximation to include quantum noise gives a unified picture of the statistical properties of the laser light for negative pump parameters. These include intensity fluctuations and discontinuous changes of the most probable intensity. An alternative approximation (obtained within the same scheme) is discussed for situations above threshold.

  20. Pumped up Lasers

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Cutting Edge Optronics released the first of potentially three products to result from an SBIR contract with Goddard Space Flight Center. The first commercial result is the WhisperMiniSlab, a diode pump for high performance laser systems. The slab uses a zig-zag path through the laser crystal which eliminates the need for thermal lensing. The result is smaller lasers with better beam quality for use in medical and industrial applications.

  1. 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.

  2. Industrial hygiene concerns of laser dyes

    Microsoft Academic Search

    1990-01-01

    A variety of materials are used as dyes in laser systems, but often very little is known about each dye's toxicity or mutagenicity\\/carcinogenicity. As a precaution, we have devised guidelines for handling these materials. We studied the literature to determine the hazards associated with various common laser dye solutions, taking into account the possible toxicity and mutagenicity\\/carcinogenicity of the solvent

  3. Nuclear pumped laser II

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J.; Lee, J. H.; Pinkston, W. T.

    1977-01-01

    The first direct nuclear pumped laser using the He-2-(n,p) H-3 reaction is reported. Lasing took place on the 1.79 microns Ar I transition in a mixture of He-3-Ar at approximately 600 Torr total pressure. It was found that the electrically pulsed afterglow He-Ar laser had the same concentration profile as the nuclear pumped laser. As a result, nuclear lasing was also achieved in He-3-Xe (2.027 micron) and He-3-Kr (2.52 micron). Scaling of laser output with both thermal flux and total pressure as well as minority concentration has been completed. A peak output (He-3-Ar) of 3.7 watts has been achieved at a total pressure of 4 atm. Direct nuclear pumping of He-3-Ne has also been achieved. Nuclear pumping of a He-3-NF3 mixture was attempted, lasing in FI at approximately 7000 A, without success, although the potential lasing transitions appeared in spontaneous emission. Both NF3 and 238UF6 appear to quench spontaneous emission when they constitute more than 1% of the gas mixture.

  4. 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.

  5. Optical noise reduction in a femtosecond Ti:sapphire laser pumped by a passively stabilized argon ion laser

    Microsoft Academic Search

    Pascal Dufour; Guy Rousseau; Michel Piché; Nathalie McCarthy

    2005-01-01

    Ionic gas lasers are widely used as optical pumps for a broad variety of solid-state and dye lasers. In such applications, the power fluctuations of the ionic gas lasers are contributing to the noise of the pumped lasers. In this paper, we report on the observation that a significant noise reduction can be achieved in a Ti:sapphire laser when it

  6. High efficiency laser-pumped emerald lasers

    Microsoft Academic Search

    S. T. Lai

    1987-01-01

    Highly efficient laser operation has been achieved in emerald. In a quasi-cw laser-pumped emerald laser, 64% output slope efficiency has been measured at 768 nm, corresponding to a laser quantum yield of 76%. An output power of 1.6 W was reached at 3.6 W of pump power at 647.1 nm from a krypton laser, and was pump power limited. The

  7. High efficiency laser-pumped emerald lasers

    Microsoft Academic Search

    S. T. Lai

    1987-01-01

    Highly efficient laser operation has been achieved in emerald. In a quasi-cw laser-pumped emerald laser, 64% output slope efficiency has been measured at 768 nm, corresponding to a laser quantum yield of 76%. An output power of 1.6 W was reached at 3.6 W of pump power at 647.1 nm from a krypton laser, and was pump power limited. The

  8. Industrial hygiene concerns of laser dyes

    Microsoft Academic Search

    1990-01-01

    A variety of materials are used as dyes in laser systems, but often very little is known about each dye`s toxicity or mutagenicity\\/carcinogenicity. As a precaution, we have devised guidelines for handling these materials. We studied the literature to determine the hazards associated with various common laser dye solutions, taking into account the possible toxicity and mutagenicity\\/carcinogenicity of the solvent

  9. Increased laser action in commercial dyes from fluorination regardless of their skeleton

    NASA Astrophysics Data System (ADS)

    Duran-Sampedro, G.; Agarrabeitia, A. R.; Arbeloa Lopez, T.; Bañuelos, J.; López-Arbeloa, I.; Chiara, J. L.; Garcia-Moreno, I.; Ortiz, M. J.

    2014-11-01

    The direct and simple fluorination of representative organic laser dyes with emission covering the entire visible spectrum, from blue to red, including Coumarin 460, Pyrromethene 546, Rhodamine 6G and Perylene Red, enhances laser efficiencies by a factor up to 1.8 with respect to the corresponding non-fluorinated parent dyes. More importantly, fluorination also significantly enhances the photostability of the dyes, even under drastic laser pumping conditions.

  10. Nano-fluidic dye laser

    E-print Network

    Gersborg-Hansen, M; Gersborg-Hansen, Morten; Kristensen, Anders

    2006-01-01

    This letter describes the design and operation of a single mode polymer-based nano-fluidic dye laser. The device relies on light-confinement in a nano-structured polymer film where an array of nano-fluidic channels is filled by capillary action with a liquid dye solution which has a refractive index lower than that of the polymer. In combination with a third order distributed feed-back (DFB) grating, formed by the array of nano-fluidic channels, this yields a low threshold for lasing. The laser is straight-forward to integrate on Lab-on-a-Chip micro-systems, e.g. for novel sensor concepts, where coherent, tunable light in the visible range is desired.

  11. Optically pumped NSF molecular laser

    SciTech Connect

    Fischer, T.A.; Tiee, J.J.; Wittig, C.

    1980-10-01

    An optically pumped NSF laser, with tunable output in the region 618--658 cm/sup -1/, and pumped with a tunable transversely excited atmosphere (TEA) CO/sub 2/ laser, is described. This laser promises to be an attractive source for laser isotope separation.

  12. dye lasers using 2-(4-Pyridyl)-5-aryloxazoles and quaternary salts of these compounds

    SciTech Connect

    Lee, L. A.

    1985-03-19

    2-(4-pyridyl)-5-aryloxazoles and certain quaternary salts of these compounds are useful as visible-wavelength lasing dyes. These dyes are used in solution with non-interferring polar solvents, such as low molecular weight alcohols, H/sub 2/O, and D/sub 2/O, to form lasing media useful in dye lasers. Such lasers generally include a reservoir for containing the laser dye solution and a pumping energy source operably coupled therewith for producing stimulated emission of the dye solution.

  13. Spin polarization and relaxation in dense cesium vapor optically pumped with second resonance laser light

    Microsoft Academic Search

    J. S. Pietras

    1980-01-01

    The first successful optical pumping of the ground state in an alkali vapor using second resonance light is reported. High density cesium vapors are optically pumped to high degrees of spin polarization using a cw dye laser tuned to the D sub 1 second resonance line of cesium (4593A). The steady-state spin polarization as a function of dye laser power

  14. Polymer-filled nanoporous silica aerogels as hosts for highly stable solid-state dye lasers.

    PubMed

    Costela, A; García Moreno, I; Gómez, C; García, O; Sastre, R; Roig, A; Molins, E

    2005-03-17

    New hybrid solid-state dye laser materials based on highly porous silica aerogels have been synthesized. The open porous network of the aerogel was saturated with laser dyes dissolved in appropriate organic monomers, and polymerization took place inside the silica structure. The resulting polymer-filled nanoporous aerogel (PFNPA) was cast in a cylindrical shape, forming monoliths that were used as gain media in solid-state dye lasers. When the PFNPA incorporated pyrromethene dyes, highly photostable laser emission with good lasing efficiency was obtained. Under the demanding conditions of tightly focused transversal pumping with 532 nm, 5 mJ pulses at 10 Hz repetition rate, the commercial dye Pyrromethene 567 exhibited laser action with only a 10% drop in the laser output after 10(6) pump pulses in the same position of the sample. PMID:16851520

  15. Industrial hygiene concerns of laser dyes

    SciTech Connect

    Miller, G.

    1990-11-01

    A variety of materials are used as dyes in laser systems, but often very little is known about each dye`s toxicity or mutagenicity/carcinogenicity. As a precaution, we have devised guidelines for handling these materials. We studied the literature to determine the hazards associated with various common laser dye solutions, taking into account the possible toxicity and mutagenicity/carcinogenicity of the solvent used. Working from this information, we have proposed three control classes -- limited, moderate, and strict -- for work performed with dyes in each class. This paper describes the considerations that went into preparing our guidelines and summarizes the precautions themselves.

  16. 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.

  17. Solar Pumped Laser Microthruster

    SciTech Connect

    Rubenchik, A. M.; Beach, R.; Dawson, J.; Siders, C. W. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore CA 94550 (United States)

    2010-10-08

    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. Retuneable organic dye solution laser, excited by a nitrogen laser

    Microsoft Academic Search

    Yu. I. Bychkov; V. F. Losev; V. I. Revenko; V. F. Tarasenko; V. B. Timofeev

    1975-01-01

    Organic dye lasers, excited by pulse nitrogen lasers (N 2 lasers) may be used in a whole range of spectroscopic investigations, since the high pulse repetition frequency of generation (~ 102 Hz) allows the well-known stroboscopic recording technique to be used successfully [1]. This paper describes a simple reliable laser of this type. To excite generation in the dyes, we

  19. Highly photostable solid-state dye lasers based on silicon-modified organic matrices

    NASA Astrophysics Data System (ADS)

    Costela, A.; García-Moreno, I.; del Agua, D.; García, O.; Sastre, R.

    2007-04-01

    We report on the synthesis, characterization, and physical properties of modified polymeric matrices incorporating silicon atoms in their structure and doped with laser dyes. When the silicon-modified organic matrices incorporated pyrromethene 567 (PM567) and pyrromethene 597 (PM597) dyes as actual solid solutions, highly photostable laser operation with reasonable, nonoptimized efficiencies was obtained under transversal pumping at 532nm. At a pump repetition rate of 10Hz, the intensity of the laser emission remained at the level or above the initial lasing intensity after 100 000 pump pulses in the same position of the sample, corresponding to an estimated accumulated pump energy absorbed by the system of 518 and 1295GJ/mol for PM567 and PM597, respectively. When the pump repetition rate was increased to 30Hz, the laser emission of dye PM567 decreased steadily and the output energy fell to one-half its initial value after an accumulated pump energy of 989 GJ/mol. Dye PM597 demonstrated a remarkable photostability, and under 30Hz pumping the laser emission from some samples remained stable after 700 000 pump pulses in the same position of the sample, corresponding to an accumulated pump energy of 17300GJ/mol. Narrow linewidth operation with tuning ranges of up to 31nm was obtained with both pyrromethene dyes when some of the samples were incorporated into a grazing-incidence grating oscillator.

  20. Spectral broadening in a microdroplet dye laser

    NASA Astrophysics Data System (ADS)

    Knospe, Anders G.; Kwok, Alfred S.

    2004-05-01

    We have observed broadening of the lasing spectrum of 60-?m diameter micrdroplet dye lasers. The spectral width of microdroplet dye lasers consisting of Rhodamine 6G or Pyrromethene 597 is essentially constant when water is used as a solvent but broaden by >30% at high input-laser intensities when ethanol is used as solvent. Spectral broadening is preceded by stimulated Raman scattering of ethanol in the microdroplets as the input-laser intensity increases.

  1. Experimental Investigation of Laser Emission of Dye-Doped Cholesteric Liquid Crystals with a

    E-print Network

    Wu, Shin-Tson

    like a one-dimensional photo- nic crystal laser when pumped by a second harmonic Nd-YAG pulsed laser; laser enhancement 1. INTRODUCTION Cholesteric liquid crystal (CLC) is a promising chiral photonic mediumExperimental Investigation of Laser Emission of Dye-Doped Cholesteric Liquid Crystals

  2. Tunable ultraviolet solid-state dye laser based on MPMMA doped with pyrromethene 597

    NASA Astrophysics Data System (ADS)

    Jiang, Y. G.; Fan, R. W.; Xia, Y. Q.; Chen, D. Y.

    2011-01-01

    Solid-state dye sample based on modified polymethyl methacrylate (MPMMA) co-doped with pyrromethene 597 (PM597), and coumarin 460 (C460) were prepared. A frequency-doubled pulsed Nd:YAG laser is used to pump solid-state dye sample, and the narrow linewidth dye laser of 94.4 mJ was obtained at 582 nm in an oscillator-amplifier configuration. Using a beta-BaB2O4 (BBO) crystal to frequency double the dye laser into ultraviolet (UV), a tuning range from 279 to 305 nm was demonstrated from a single doped PM597 dye. To the best of our knowledge, the UV tuning range is the best under the same condition so far. The conversion slope efficiency from solid dye laser to UV laser was 8.9% and the highest UV laser output energy reached 6.94 mJ at 291 nm.

  3. Two-Photon-Pumped Frequency-Upconverted Blue Lasing in Coumarin Dye Solution

    Microsoft Academic Search

    Guang S. He; Raffaella Signorini; Paras N. Prasad

    1998-01-01

    Two-photon-pumped (TPP) frequency-upconverted blue lasing of Coumarin 500 dye solution has been experimentally investigated. The shortest lasing wavelength was measured to be 479 nm from a Coumarin 500 solution in chloroform pumped with 800-nm laser pulses of 5-ns duration. The spectral, temporal, and spatial structures as well as the output input characteristics of TPP cavity lasing were measured with a

  4. Two-photon pumped frequency-upconversion lasing of a new blue-green dye material

    Microsoft Academic Search

    Guang S. He; Lixiang Yuan; Paras N. Prasad; Alessandro Abbotto; Antonio Facchetti; Giorgio A. Pagani

    1997-01-01

    The two-photon absorption and two-photon pumped (TPP) frequency-upconverted green lasing properties of a new dye, 1-(N-methyl-4-pyridinio)-2-(N-methylpyrrol-2-yl)ethene triflate (abbreviated as M-PPE) have been experimentally investigated. This new dye exhibits a low lasing threshold and high lasing efficiency when pumped with a 800-nm pulsed laser beam. The spectral, temporal, and spatial structures as well as the output\\/input characteristics of the TPP cavity

  5. Industrial hygiene concerns of laser dyes

    SciTech Connect

    Miller, G.

    1990-11-01

    A variety of materials are used as dyes in laser systems, but often very little is known about each dye's toxicity or mutagenicity/carcinogenicity. As a precaution, we have devised guidelines for handling these materials. We studied the literature to determine the hazards associated with various common laser dye solutions, taking into account the possible toxicity and mutagenicity/carcinogenicity of the solvent used. Working from this information, we have proposed three control classes -- limited, moderate, and strict -- for work performed with dyes in each class. This paper describes the considerations that went into preparing our guidelines and summarizes the precautions themselves.

  6. High efficiency laser-pumped emerald lasers

    NASA Astrophysics Data System (ADS)

    Lai, S. T.

    1987-09-01

    Highly efficient laser operation has been achieved in emerald. In a quasi-cw laser-pumped emerald laser, 64% output slope efficiency has been measured at 768 nm, corresponding to a laser quantum yield of 76%. An output power of 1.6 W was reached at 3.6 W of pump power at 647.1 nm from a krypton laser, and was pump power limited. The emerald laser has a tuning range of 720 to 842 nm. The round trip loss excluding the excited state absorption (ESA) is 0.4%/cm. These results indicate the high laser efficiency and the high optical quality of the emerald attainable in the present laser.

  7. High efficiency laser-pumped emerald lasers

    SciTech Connect

    Lai, S.T.

    1987-09-25

    Highly efficient laser operation has been achieved in emerald. In a quasi-cw laser-pumped emerald laser, 64% output slope efficiency has been measured at 768 nm, corresponding to a laser quantum yield of 76%. An output power of 1.6 W was reached at 3.6 W of pump power at 647.1 nm from a krypton laser, and was pump power limited. The emerald laser has a tuning range of 720 to 842 nm. The round trip loss excluding the excited state absorption (ESA) is 0.4%/cm. These results indicate the high laser efficiency and the high optical quality of the emerald attainable in the present laser.

  8. Study of excitation transfer in flowing helium afterglow pumped with a tuneable dye laser. 2: Measurement of the rate coefficient for the rotational relaxation of He2(3p (3 Pi g))

    NASA Technical Reports Server (NTRS)

    Collins, C. B.; Johnson, B. W.

    1972-01-01

    The rotational relaxation of the He2(3p(3pi g)) state is examined by optically pumping a flowing helium afterglow with a tuneable dye laser. The population of the J = 8 rotational state is enhanced by optically saturating the R sub 7 component of the transition connecting this state with the metastable He2(2s (3 Sigma u +)) molecular state. From the lifetime and yield of the Q sub 7 component, the rate coefficient for the rotational relaxation via the forbidden delta J = 1 channel is determined to be of the order of 2 x 10 to the minus 11th power cm3/sec. It is found that this represents about half of the total rate of rotational relaxation in this state.

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

    E-print Network

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

    2015-01-01

    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.

  10. Silicon-containing organic matrices as hosts for highly photostable solid-state dye lasers

    NASA Astrophysics Data System (ADS)

    Costela, A.; García-Moreno, I.; del Agua, D.; García, O.; Sastre, R.

    2004-09-01

    Modified polymeric matrices incorporating silicon atoms in their structure and doped with lasing dyes have been synthesized and demonstrated to render improved laser performance. When transversely pumped at 532nm, highly stable laser operation with reasonable, not-optimized efficiencies was obtained. Materials were prepared where dyes pyrromethene 567 and pyrromethene 597 emitted laser radiation with no sign of degradation in the laser output, albeit with some oscillations, after 100 000pump pulses in the same position of the sample at 10Hz repetition rate.

  11. Femtosecond ring dye laser: a potential new laser gyro.

    PubMed

    Dennis, M L; Diels, J C; Lai, M

    1991-04-01

    Measurements on a passively mode-locked dye laser demonstrate a sensitive gyro-type response, when Fresnel drag in air is used to simulate rotation. Such a response is unexpected for a homogeneously broadened ring laser. PMID:19773989

  12. Transverse-pumped Cs vapor laser

    Microsoft Academic Search

    B. V. Zhdanov; M. K. Shaffer; J. Sell; R. J. Knize

    2009-01-01

    Scaling of alkali lasers to higher powers requires combining beams of multiple diode laser pump sources. For longitudinal pumping this can be very complicated if more than four beams are to be combined. In this paper we report a first demonstration of a transversely pumped Cs laser with fifteen laser diode arrays. The LDA pump beams were individually collimated with

  13. Rotational relaxation and triplet-state effects in the cw dye laser

    Microsoft Academic Search

    A. E. Siegman; D. W. Phillion; D. J. Kuizenga

    1972-01-01

    In a cw dye laser apparatus we measure first the fluorescence depolarization in the usual manner, and then the ratio of laser threshold pump powers for the laser polarization parallel and perpendicular to the linearly polarized pump source. From these two measurements we can obtain the important triplet-state parameter KT ? kST?T?T? ?e, as well as the rotational relaxation time

  14. Raman-shifted dye laser for water vapor DIAL measurements

    NASA Technical Reports Server (NTRS)

    Grossmann, B. E.; Singh, U. N.; Cotnoir, L. J.; Wilkerson, T. D.; Higdon, N. S.; Browell, E. V.

    1987-01-01

    For improved DIAL measurements of water vapor in the upper troposphere or lower stratosphere, narrowband (about 0.03/cm) laser radiation at 720- and 940-nm wavelengths was generated by stimulated Raman scattering (SRS), using the narrow linewidth (about 0.02/cm) output of a Nd:YAG-pumped dye laser. For a hydrogen pressure of 350 psi, the first Stokes conversion efficiencies to 940 nm were 20 percent and 35 percent, when using a conventional and waveguide Raman cell, respectively. The linewidth of the first Stokes line at high cell pressures, and the inferred collisional broadening coefficients, agree well with those previously measured in spontaneous Raman scattering.

  15. Epoxy matrix for solid-state dye laser applications.

    PubMed

    Cazeca, M J; Jiang, X; Kumar, J; Tripathy, S K

    1997-07-20

    The preparation and performance of an epoxy-based matrix impregnated with Pyrromethene 580 for solid-state dye laser applications are discussed. The matrix proved to be stable and efficient as a laser medium when pumped by a frequency-doubled, Q-switched Nd:YAG laser with a 10-ns pulse width. Stability measurements were performed on a 1-mm-thick epoxy sample, doped with Pyrromethene 580 at a concentration of 4 x 10(-3) M. When the sample was pumped at millijoule energy levels, the stability was measured to be ~55,000 pulses from a single spot on the sample before the power dropped by a factor of half. PMID:18259301

  16. Dye laser amplifier including a dye cell contained within a support vessel

    DOEpatents

    Davin, James (Gilroy, CA)

    1992-01-01

    A large (high flow rate) dye laser amplifier in which a continous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of greater than 30 gallons/minute at a static pressure greater than 150 pounds/square inch and a specifically designed support vessel for containing the dye cell.

  17. Confinement of pyridinium hemicyanine dye within an anionic metal-organic framework for two-photon-pumped lasing

    PubMed Central

    Yu, Jiancan; Cui, Yuanjing; Xu, Hui; Yang, Yu; Wang, Zhiyu; Chen, Banglin; Qian, Guodong

    2013-01-01

    Two-photon-pumped dye lasers are very important because of their applications in wavelength up-conversion, optical data storage, biological imaging and photodynamic therapy. Such lasers are very difficult to realize in the solid state because of the aggregation-caused quenching. Here we demonstrate a new two-photon-pumped micro-laser by encapsulating the cationic pyridinium hemicyanine dye into an anionic metal-organic framework (MOF). The resultant MOF?dye composite exhibits significant two-photon fluorescence because of the large absorption cross-section and the encapsulation-enhanced luminescent efficiency of the dye. Furthermore, the well-faceted MOF crystal serves as a natural Fabry–Perot resonance cavity, leading to lasing around 640?nm when pumped with a 1064-nm pulse laser. This strategy not only combines the crystalline benefit of MOFs and luminescent behaviour of organic dyes but also creates a new synergistic two-photon-pumped lasing functionality, opening a new avenue for the future creation of solid-state photonic materials and devices. PMID:24173352

  18. 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.

  19. Far-red polyurethane-host solid-state dye laser

    SciTech Connect

    Nikolaev, S V; Pozhar, V V; Dzyubenko, M I [A.Ya. Usikov Institute of Radiophysics and Electronics, National Academy of Sciences of Ukraine, Khar'kov (Ukraine); Doroshenko, A O [Research Institute of Chemistry, V. N. Karazin Kharkiv National University, Kharkov (Ukraine)

    2009-09-30

    The output energy and emission spectrum of a solid-state dye laser using Oxazine 1 in polyurethane as the gain medium have been measured. Under microsecond pumping, efficient lasing has been obtained in the range 700-745 nm. The highest conversion efficiency and output energy achieved are 23% and 127 mJ, respectively. (lasers)

  20. Liquid Droplet Dye Laser M.Sc. Thesis

    E-print Network

    Liquid Droplet Dye Laser M.Sc. Thesis Hatim Azzouz Supervisors: Anders Kristensen, Niels Asger on the frontpage is a liquid droplet dye laser levitated by a so-called levitator apparatus. Hatim Azzouz 1 #12

  1. 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.

  2. Linewidth characteristics of Raman-shifted dye laser output at 720 and 940 nm

    NASA Technical Reports Server (NTRS)

    Grossmann, B. E.; Higdon, N. S.; Higdon, N. S.; Higdon, N. S.; Higdon, N. S.; Higdon, N. S.; Higdon, N. S.

    1986-01-01

    Existing DIAL systems for water vapor measurements in the troposphere operate at wavelengths near 720 nm. The use of stronger water vapor absorption lines in the range 930 to 960 nm will significantly improve DIAL measurements in the upper troposphere and lower stratosphere where water vapor concentrations are low. The generation of light at 940 nm using a frequency doubled Nd:YAG pumped dye laser is inefficient due to the small absorption if infrared dyes at the pump wavelength. However, 940 nm generation utilizing stimulated Raman scattering of dye lasers is attractive because of a potentially high conversion efficiency plus the possibility of retaining the narrow linewidth available from some dye lasers. The Raman conversion efficiency and line broadening are presented for first Stokes operation at 720 and 940 nm using hydrogen and deuterium as the Raman media.

  3. 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.

  4. Enhanced laser performances based on energy transfer in multi-dyes co-doped solid media

    NASA Astrophysics Data System (ADS)

    Yang, Yu; Lin, Guannan; Zou, Juan; Wang, Zhiyu; Wang, Minquan; Qian, Guodong

    2007-09-01

    Various coumarin dyes are co-doped with perylene red (P-red) and pyrromethene 567 (PM567) into vinyltriethoxysilane-derived solid media, respectively. Energy transfer among laser dyes has been observed, and the effect of coumarin dye concentration on the laser properties has been investigated. With the presence of coumarin dye and pyrromethene 567, enhanced laser performances based on energy transfer of perylene red have been exhibited. The laser efficiency can be improved by two-fold and broad tunable range as wide as 80 nm can be achieved. At the pump intensity of 1.0 J/cm 2, the laser output of co-doping perylene red decreases less than 30% after 30,000 pulses.

  5. Progress in solar-pumped laser research

    NASA Technical Reports Server (NTRS)

    De Young, R. J.; Conway, E. J.

    1986-01-01

    High-power solar-pumped lasers could eventually provide power in space for electric and propulsive needs. Recent research results are presented showing progress on both direct-pumped and blackbody-pumped solar lasers. Using a solar simulator, lasing of C3F7I at 10 watts has been achieved. Using C4F9I, lasing thresholds as low as 170 solar constants have been demonstrated, which is the lowest threshold value for a solar-pumped gas laser to date. Blackbody-pumped CO2 lasers have achieved outputs of 180 milliwatts for cavity-pumped and 1.4 watts in transfer-pumped systems.

  6. Compact and highly efficient laser pump cavity

    DOEpatents

    Chang, Jim J. (Dublin, CA); Bass, Isaac L. (Castro Valley, CA); Zapata, Luis E. (Livermore, CA)

    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.

  7. Efficient Optically Pumped Cesium Vapor Laser

    Microsoft Academic Search

    B. Zhdanov; T. Ehrenreich; R. J. Knize

    2006-01-01

    We have demonstrated a cesium laser with 81% slope efficiency relative to the input pump power. The maximum output power at 894 nm was 0.36 W with a pump power of 0.57 W (the overall optical efficiency was 63%). Optically pumped alkali lasers have a number of desirable features as compared to solid state or fiber lasers: the quantum efficiency

  8. Intracavity absorption with a continuous wave dye laser - Quantification for a narrowband absorber

    NASA Technical Reports Server (NTRS)

    Brobst, William D.; Allen, John E., Jr.

    1987-01-01

    An experimental investigation of the dependence of intracavity absorption on factors including transition strength, concentration, absorber path length, and pump power is presented for a CW dye laser with a narrow-band absorber (NO2). A Beer-Lambert type relationship is found over a small but useful range of these parameters. Quantitative measurement of intracavity absorption from the dye laser spectral profiles showed enhancements up to 12,000 (for pump powers near lasing threshold) when compared to extracavity measurements. The definition of an intracavity absorption coefficient allowed the determination of accurate transition strength ratios, demonstrating the reliability of the method.

  9. Pulsed dye laser treatment of burn scars

    Microsoft Academic Search

    K. P Allison; M. N Kiernan; R. A Waters; R. M Clement

    2003-01-01

    Introduction: Burn scars are very common in both children and adults, causing great morbidity and often pose a difficult management problem. This study investigated the efficacy of the dye laser in patients with symptomatic burn scars and analysed the impact of the laser treatment on scar redness, surface texture and pruritis.Methods: Patients were placed into four groups—adult new scar (n=8),

  10. Stored energy in pulsed dye laser ampifiers

    SciTech Connect

    Hnilo, A.A.; Martinez, O.E.; Quel, E.J.

    1986-01-01

    A new, more complete geometrical description of amplified spontaneous emission is included in the usual numerical models for dye laser amplifiers. A strong discrepancy with previous models is found for the low input signal regime and when evaluating the stored energy. The model was thoroughly tested experimentally.

  11. Dye laser amplifier including a low turbulence, stagnation-free dye flow configuration

    DOEpatents

    Davin, J.

    1992-12-01

    A large (high flow rate) dye laser amplifier in which a continuous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of for example 30 gallons/minute, a specifically designed support vessel for containing the dye cell and a screen device for insuring that the dye stream passes into the dye cell in a substantially turbulent free, stagnation-free manner. 9 figs.

  12. Dye laser amplifier including a low turbulence, stagnation-free dye flow configuration

    DOEpatents

    Davin, James (Gilroy, CA)

    1992-01-01

    A large (high flow rate) dye laser amplifier in which a continuous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of for example 30 gallons/minute, a specifically designed support vessel for containing the dye cell and a screen device for insuring that the dye stream passes into the dye cell in a substantially turbulent free, stagnation-free manner.

  13. 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.

  14. Fusion pumped laser

    DOEpatents

    Pappas, Daniel S. (Los Alamos, NM)

    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.

  15. Photophysics of Laser Dye-Doped Polymer Membranes for Laser-Induced Fluorescence Photogrammetry

    NASA Technical Reports Server (NTRS)

    Dorrington, Adrian A.; Jones, Thomas W.; Danehy, Paul M.

    2004-01-01

    Laser-induced fluorescence target generation in dye-doped polymer films has recently been introduced as a promising alternative to more traditional photogrammetric targeting techniques for surface profiling of highly transparent or reflective membrane structures. We investigate the photophysics of these dye-doped polymers to help determine their long-term durability and suitability for laser-induced fluorescence photogrammetric targeting. These investigations included experimental analysis of the fluorescence emission pattern, spectral content, temporal lifetime, linearity, and half-life. Results are presented that reveal an emission pattern wider than normal Lambertian diffuse surface scatter, a fluorescence time constant of 6.6 ns, a pump saturation level of approximately 20 micro J/mm(exp 2), and a useful lifetime of more than 300,000 measurements. Furthermore, two demonstrations of photogrammetric measurements by laser-induced fluorescence targeting are presented, showing agreement between photogrammetric and physically measured dimensions within the measurement scatter of 100 micron.

  16. Solid-state dye lasers based on PMMA co-doped with PM597 and PM650

    NASA Astrophysics Data System (ADS)

    Wang, G. M.; Zhang, Z. H.

    2011-06-01

    In order to enhance the laser performances, solid-state samples based on polymethyl methacrylate (PMMA) co-doped with pyrromethene 597 (PM597) and pyrromethene 650 (PM650) were prepared. With SHG of Q-switched Nd:YAG laser (532 nm, ˜15 ns) pumping the samples, laser emission from the mixtures of PM597 and PM650 both in liquid solution and incorporated into solid polymeric matrices were investigated. The highest slope efficiency of co-doped solid-state dye samples 30.8% was achieved. Through the dye PM650 being co-doped into the dye PM597, the dye laser output wavelength was extended for the existence of energy transfer from the dye PM597 to the dye PM650.

  17. Investigations of fluctuations in one- and two-mode dye lasers

    SciTech Connect

    Gage, E.C.

    1989-01-01

    The intensity fluctuations of one- and two-mode dye lasers are investigated experimentally and theoretically, in the latter case by means of numerical integration of the equations of motion for the various laser models. Third-order theories appropriate for lasers not too far above threshold are augmented by an additive noise term to represent spontaneous emission and a multiplicative noise term to model population inversion fluctuations. Two source of the pump fluctuations, variations in the optical pump power and fluctuations in the dye flow are studied, and the former is found to be a stochastic process whereas the latter is chaotic due to the turbulent fluid flow. The introduction of finite-bandwidth, colored pump noise leads to predictions of new features in the laser behavior, and the model is compared to the standard lager model without pump noise, and a model with white pump noise. The new features predicted and observed include large intensity fluctuations below threshold, a first-order phase transition analogy, and an initial flat region in the shape of the time dependent intensity auto-correlation. The features are all well modeled by the equations of motion with colored pump noise, but some discrepancies remain. In the homogeneously broadened two-mode ring laser, the strong mode competition leads to random anti-correlated mode-switching. System behavior with a dye jet and a dye cell is compared. Attention is given to the role of an induced differential loss for the two-counter propagating modes. The insertion of an optical diode, an electromagnetic Faraday rotator and a crystal quartz rotator, allows the intensity statistics to be investigated as a function of asymmetry. The results are found to be in good agreement with the model with colored pump noise, and if a rescaling of the effective asymmetry is allowed the results are also in reasonable agreement with the model without pump noise.

  18. 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.

  19. 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.

  20. Modeling laser performance of scalable side pumped alkali laser

    Microsoft Academic Search

    Aleksey M. Komashko; Jason Zweiback

    2010-01-01

    Diode pumped alkali lasers (DPAL) offer the potential for high power and efficient operation. The extremely low quantum defect of the alkali system minimizes thermal management requirements. At the same time DPALs keep advantages of gas lasers (no thermal stresses, high intrinsic beam quality). Side pumped geometry simplifies system design, separating laser and pump light and providing physical space for

  1. Tunable solid-state lasers based on PMMA doped with pyrromethene dyes

    NASA Astrophysics Data System (ADS)

    Jiang, Y. G.; Fan, R. W.; Peng, H.; Xia, Y. Q.; Chen, D. Y.

    2009-03-01

    Tunable solid-state dye laser samples based on poly methyl methacrylate (PMMA) doped with PM567 and PM580 were prepared and the laser performances for them were studied in this letter. With pump repetition rate of 1 Hz and incident intensity of 0.1 J/cm2, more than 30 nm wide tunable range had all been achieved using the two samples, and the highest slope efficiency of 52.08% was obtained in the sample PM567. To the best of our knowledge, the efficiency is the highest under the same condition so far. The linewidth for the laser was measured with the result of less than 0.2 nm. All results indicate that the high laser performance using tunable solid-state dye lasers based on PMMA doped with PM dyes can be achieved.

  2. Solid-state dye lasers based on polymethyl methacrylate doped with pyrromethene 650

    NASA Astrophysics Data System (ADS)

    Wang, G. M.; Zhang, Z. H.

    2010-10-01

    Solid-state dye samples based on polymethyl methacrylate (PMMA) doped with different concentrations of the dye PM650 were prepared. With SHG of Q-switched Nd:YAG laser (532 nm, ˜15 ns) pumping the samples longitudinally, the fluorescence, lasing spectra and slope efficiencies of the samples were obtained. The highest slope efficiency 27.49% and laser output energy 22.0 mJ was achieved in the sample with a dye concentration of 2.0 × 10-4 mol/L. To our knowledge, the results are the best under the same condition so far. The maxima of output lasing spectrum is about 653.5 nm. Our results have shown that using solid-state samples doped with PM650 can extend the dye laser wavelength to the red.

  3. Diode laser-pumped solid-state lasers

    Microsoft Academic Search

    T. Y. Fan; R. L. Byer

    1988-01-01

    Recently, interest in diode laser-pumped solid-state lasers has increased due to their advantages over flashlamp-pumped solid-state lasers. The authors present a historical overview of semiconductor diode-pumped solid-state lasers beginning with work in the early 1960's and extending to recent work on wavelength extension of these devices by laser operation on new transitions. Modeling of these devices by rate equations to

  4. Optofluidic microcavities: Dye-lasers and biosensors

    PubMed Central

    Chen, Y.; Lei, L.; Zhang, K.; Shi, J.; Wang, L.; Li, H.; Zhang, X. M.; Wang, Y.; Chan, H. L. W.

    2010-01-01

    Optofluidic microcavities are integrated elements of microfluidics that can be explored for a large variety of applications. In this review, we first introduce the physics basis of optical microcavities and microflow control. Then, we describe four types of optofluidic dye lasers developed so far based on both simple and advanced device fabrication technologies. To illustrate the application potential of such devices, we present two types of laser intracavity measurements for chemical solution and single cell analyses. In addition, the possibility of single molecule detection is discussed. All these recent achievements demonstrated the great importance of the topics in biology and several other disciplines. PMID:24753719

  5. Compression mechanism of subpicosecond pulses by malachite green dye in passively mode-locked rhodamine 6G/DODCI CW dye lasers

    SciTech Connect

    Watanabe, A.; Hara, M.; Kobayashi, H.; Takemura, H.; Tanaka, S.

    1983-04-01

    The pulse width compression effect of a malachite green (MG) dye upon subpicosecond pulses has been experimentally investigated in a CW passively mode-locked rhodamine 6G/DODCI dye laser. The pulse width reduces as MG concentration increases, and reaches 0.34 ps at 1.5 X 10/sup -6/ M. By adding the MG dye, good mode locking is achieved in a rather wide pumping-power range. A computer simulation of pulse growth has also been carried out by using simple rate equations, in which the fast-recovery component of loss due to the MG dye is taken into account. The simulated results can explain some experimental results qualitatively such as pulse width compression and pumping-power restriction. The pulse width compression results essentially from the fast recovery of cavity loss caused by the MG dye.

  6. Preliminary investigation of the effects of dye concentration on the output of a multiwavelength dye laser

    NASA Technical Reports Server (NTRS)

    Clark, I. O.; Burney, L. G.

    1974-01-01

    The effects of dye concentration on the output wavelength and energy of a multiwavelength dye laser were investigated. The dyes tested were Coumarin 2 in methyl alcohol and Rhodomine 6G, Acridine Red, and 7-diethylamino-4-methyl Coumarin (7DA 4MC) in ethyl alcohol.

  7. Dye laser amplifier including a specifically designed diffuser assembly

    DOEpatents

    Davin, James (Gilroy, CA); Johnston, James P. (Stanford, CA)

    1992-01-01

    A large (high flow rate) dye laser amplifier in which a continuous replened supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a relatively high flow rate and a specifically designed diffuser assembly for slowing down the flow of dye while, at the same time, assuring that as the dye stream flows through the diffuser assembly it does so in a stable manner.

  8. Rubidium vapor laser pumped by two laser diode arrays.

    PubMed

    Zhdanov, Boris V; Stooke, Adam; Boyadjian, Gregory; Voci, Adam; Knize, R J

    2008-03-01

    Scaling of alkali lasers to higher powers requires using multiple diode lasers for pumping. The first (to our knowledge) results of a cw rubidium laser pumped by two laser diode arrays are presented. A slope efficiency of 53%, total optical efficiency of 46%, and output power of 17 W have been demonstrated. PMID:18311276

  9. 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.

  10. Highly stable solid state dye lasers based on polymer-filled nanoporous silica aerogels

    NASA Astrophysics Data System (ADS)

    Costela, Angel; Garcia-Moreno, Inmaculada; Gomez, Clara; Garcia, Olga; Sastre, Roberto; Molins, Elies; Roig, Anna

    2004-09-01

    New hybrid matrices based on silica aerogels obtained under supercritical conditions, a highly porous material with porosityt up to 90%, have been synthesized. The open porous network of the aerogel was saturated with pyrromethene dyes solved in organic mooners, and polymerization took place inside of the silica structure. The resulting polymer filled nanoporous aerogels, cast in the form of cylindrical monoliths, were used as gain media in solid-state dye lasers. Under the demanding conditions of tightly focused transversal pumping with 532 nm, 5 mJ pulses at 10 Hz repetition rate, highly photostable laser emission was obtained.

  11. Model of a multiple-line distributed-feedback dye laser

    NASA Astrophysics Data System (ADS)

    Khan, Nasrullah

    2004-01-01

    The theoretical basis for simultaneous oscillation of 2N - 3 laser lines is due to interference of N (for all even N >= 2) pump beams in a distributed-feedback dye laser is described. Multiple gratings are produced in a dye solution by interference patterns of N/2 pairs of a frequency-doubled Nd:YAG laser. N/2 pairs of mutually time-delayed pulses induce multiple gratings of different periodicities, of which 2N - 3 gratings support oscillation of 2N - 3 lines and the remaining gratings, because of their larger periods, cannot support Bragg scattering. The maximum number of laser lines depends on the mutual delay between adjacent pairs of beams, coherence, states of polarization, pulse lengths, and of course the number of pulses. For three pairs of excitation beams derived from the same source through wave-front or amplitude phase division techniques, the output lasing lines varied from a minimum of three to a maximum of nine. This research was carried out by pumping of a dye solution with two, four, and six pulses, but the principle may be extended to multiple output lines, depending on the number of pump pulses and on the gain of the dye solution.

  12. 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

  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. Frequency stabilization for a 486nm dye-ring laser

    E-print Network

    Sievers, Charles A. (Charles Anders), 1979-

    2004-01-01

    For my thesis, I worked towards using two reference cavities to provide frequency stabilization to a 486nm dye-ring laser. After a doubling cavity doubles the frequency to 243nm, the laser beam is used to excite ground ...

  15. Mechanism for pumping lasers with squeezed light

    SciTech Connect

    Haake, F.; Walls, D.F.; Collett, M.J.

    1989-03-15

    In this paper we demonstrate how the squeezed-pump-laser model of Marte and Walls (Phys. Rev. A 37, 1235 (1988)) may be realized in practice. We consider a three-level atomic medium interacting with two cavity modes pumped with squeezed light. We show that this pumping mechanism both achieves atomic inversion and squeezes the fluctuations on the lasing transition.

  16. RICE UNIVERSITY Pulsed Dye Laser For Excitation Of Strontium

    E-print Network

    Killian, Thomas C.

    RICE UNIVERSITY Pulsed Dye Laser For Excitation Of Strontium by Priya Gupta A Thesis Submitted April, 2004 #12;2 #12;#12;iii ABSTRACT Pulsed Dye Laser For Excitation Of Strontium by Priya Gupta that is used to make ultracold strontium plasma. In order to make ultracold plasma, we cool and trap strontium

  17. Resonantly pumped optical pumping injection cavity lasers

    E-print Network

    Santilli, Michael Robert; McAlpine, T. C.; Greene, K. R.; Olafsen, L. J.; Bewley, W. W.; Felix, C. L.; Vurgaftman, I.; Meyer, J. R.; Lee, H.; Martinelli, R. U.

    2004-11-01

    in the active region. In the inte- grated absorber (IA) method first introduced for the type-II antimonides by the Massachusetts Institute of Technology Lincoln Laboratory 9–11 and further developed at the Air Force Research Laboratory, 6–8 thick GaInAsSb layers... region is enclosed between two GaSb/AlAsSb-distributed Bragg reflector (DBR) mirrors that induce multiple passes of the pump beam. A schematic is shown in Fig. 1. Tuning the etalon resonance to the pump wavelength (but not to the mid-IR emission...

  18. 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.

  19. Limitations of an optically pumped rubidium laser imposed by atom recycle rate

    Microsoft Academic Search

    W. S. Miller; C. V. Sulham; J. C. Holtgrave; G. P. Perram

    2011-01-01

    A rubidium laser pumped on the 52S1\\/2-52P3\\/2 D2 transition by a pulsed dye laser at pump intensities exceeding 3.5 MW\\/cm2 (>1000 times threshold) has been demonstrated. Output energies as high as 12 muJ\\/pulse are limited by the rate for collision relaxation of the pumped 2P3\\/2 state to the upper laser 2P1\\/2 state. More than 250 photons are available for every

  20. Limitations of an optically pumped rubidium laser imposed by atom recycle rate

    Microsoft Academic Search

    W. S. Miller; C. V. Sulham; J. C. Holtgrave; G. P. Perram

    2011-01-01

    A rubidium laser pumped on the 52S1\\/2–52P3\\/2 D2 transition by a pulsed dye laser at pump intensities exceeding 3.5 MW\\/cm2 (>1000 times threshold) has been demonstrated. Output energies as high as 12 ?J\\/pulse are limited by the rate for collision\\u000a relaxation of the pumped 2P3\\/2 state to the upper laser 2P1\\/2 state. More than 250 photons are available for every rubidium

  1. Chirp control of a single-mode, good beam quality, zigzag dye laser

    SciTech Connect

    Mandl, A.; Zavriyev, A.; Klimek, D.E. [Textron Systems Div., Wilmington, MA (United States)] [Textron Systems Div., Wilmington, MA (United States)

    1997-03-01

    The authors report a substantial reduction of frequency chirp of a single-mode laser-pumped zigzag dye laser. A linear optical cavity using counterpropagating orthogonally polarized waves was injection-seeded at 568 nm and operated with a laser output of about 1 J. The chirp was controlled by an intracavity Pockels cell that was configured to add optical density at a rate which counterbalanced the decrease in optical density due to dye-solvent heating during the {approximately}1-{micro}s laser pulse. Heterodyne measurements were used to determine that the bandwidth was near the transform limit and chirp rate of {approximately}1 MHz/{micro}s. The beam quality of the laser was measured at 10 Hz as 1.7 XDL.

  2. Role of the stimulated-emission rate in the photostability of solid-state dye lasers

    NASA Astrophysics Data System (ADS)

    Ray, Alok Kumar; Kumar, Sasi; Vitthal Mayekar, Narayan; Sinha, Sucharita; Kundu, Soumitra; Chattopadhyay, Subrata; Dasgupta, Kamalesh

    2005-12-01

    The lasing and photostability characteristics of Rhodamine 6G and Pyrromethene 567 dyes dispersed in polymeric host materials have been investigated as a function of the intensities of incident pump and signal beams in a longitudinally pumped dye laser in an oscillator-amplifier configuration. A substantial reduction in the rate of photodegradation was observed under lasing conditions and with increasing signal intensity in a dye amplifier, establishing that the service lives of these materials improve with an increase in the rate of stimulated emission. We observed ˜62% amplifier efficiency at 2 Hz operation and 10% reduction in amplifier efficiency at 10 Hz operation after exposure of 72,000 pulses by use of a Pyrromethene disk.

  3. Role of the stimulated-emission rate in the photostability of solid-state dye lasers.

    PubMed

    Ray, Alok Kumar; Kumar, Sasi; Mayekar, Narayan Vitthal; Sinha, Sucharita; Kundu, Soumitra; Chattopadhyay, Subrata; Dasgupta, Kamalesh

    2005-12-20

    The lasing and photostability characteristics of Rhodamine 6G and Pyrromethene 567 dyes dispersed in polymeric host materials have been investigated as a function of the intensities of incident pump and signal beams in a longitudinally pumped dye laser in an oscillator-amplifier configuration. A substantial reduction in the rate of photodegradation was observed under lasing conditions and with increasing signal intensity in a dye amplifier, establishing that the service lives of these materials improve with an increase in the rate of stimulated emission. We observed approximately 62% amplifier efficiency at 2 Hz operation and 10% reduction in amplifier efficiency at 10 Hz operation after exposure of 72,000 pulses by use of a Pyrromethene disk. PMID:16381533

  4. 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.

  5. 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.

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

    Microsoft Academic Search

    Kurt J. Linden; Patrick N. McDonnell

    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

  7. Theoretical studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

    The power output of a black body solar-pumped laser as a function of time (computer graphic solutions) and under steady state conditions (analytic conditions); computer analyses of polymerization using lasers; and metallic sodium as a laser medium were studied.

  8. Exploding conducting film laser pumping apparatus

    DOEpatents

    Ware, Kenneth D. (San Diego, CA); Jones, Claude R. (Los Alamos, NM)

    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.

  9. Closely spaced mirror pair for reshaping and homogenizing pump beams in laser amplifiers

    SciTech Connect

    Bass, I.L.

    1992-12-01

    Channeling a laser beam by multiple reflections between two closely-spaced, parallel or nearly parallel mirrors, serves to reshape and homogenize the beam at the output gap between the mirrors. Application of this device to improve the spatial overlap of a copper laser pump beam with the signal beam in a dye laser amplifier is described. This technique has been applied to the AVLIS program at the Lawrence Livermore National Laboratory.

  10. 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.

  11. Fluorescence enhancement monitoring of pyrromethene laser dyes by metallic Ag nanoparticles.

    PubMed

    Sakr, Mahmoud E M; Abou Kana, Maram T H; Abdel Fattah, Gamal

    2014-11-01

    Fluorescence enhancement monitoring of pyrromethene laser dyes using their complexation with Ag nanoparticles (Ag NPs) was studied. The size of the prepared Ag NPs was determined by transmission electron spectroscopy and UV/Vis absorption spectroscopy. Mie theory was also used to confirm the size of NPs theoretically. The effect of different nanoparticle concentrations on the optical properties of 1 × 10(-4) M PM dyes shows that 40%of Ag NPs concentration (40%C Ag NPs) in complex is the optimum concentration. Also, the effects of different concentrations of PM dyes in a complex was measured. Emission enhancement factors were calculated for all samples. Fluorescence enhancement efficiencies depended on the input pumping energy of a Nd-YAG laser (wavelength 532 nm and 8 ns pulse duration) were reported and showed the lowest energy (28 and 32 mJ) in the case of PM567 and PM597, respectively. PMID:24652745

  12. Energy scaling of flashlamp-pumped titanium sapphire lasers

    NASA Astrophysics Data System (ADS)

    Blair, Randall J.; Hauck, James P.

    1993-06-01

    We have developed an accurate simulation program to predict the performance of flashlamp- pumped Titanium Sapphire (TiS) lasers. The program has been benchmarked to several experimental lasers with energy outputs from 0.1 to 1.0 Joules per pulse. The results for lasers operating in both long-pulse and Q-switched modes agree with experimental results to within 20%. We have used this program to explore energy scaling of TiS laser oscillators from 1.0 to 10.0 Joules using realistic values for lamp pulse energy loading and TiS material Figure-of- Merit (FOM). We present here results of this energy scaling as explicit functions of laser rod diameter, length, doping level, Figure of Merit, use of dye converters, pump pulse length and number of lamps. The results indicate that with proper lamp coupling, via reflectors, etc., lasers with pulse energies greater than 10 Joules are possible with electrical-to-output efficiency greater than 1%.

  13. Eyesafe diode-pumped erbium lasers

    SciTech Connect

    DeShazer, L.G. [McDonnell Douglas Aerospace, St. Louis, MO (United States)

    1994-12-31

    A pulsed erbium glass laser operated at 1,533 nm using transverse pumping by four 12-bar laser diode subarrays at 932 nm. The laser ran in free-running and Q-switched modes, using both electro-optical and mechanical switches. With a LiNbO{sub 3} Pockels cell Q-switch, the erbium laser achieved 57 mJ energy per pulse, 26 ns pulsewidth and 3 Hz repetition rate.

  14. 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.

  15. New optically pumped alkali metal dimer lasers

    Microsoft Academic Search

    A. Rajaei-Rizi; J. T. Bahns; K. K. Verma; W. C. Stwalley

    1982-01-01

    Stable unidirection ring laser oscillation of optically pumped (Li-6)2 and Li-6-Li-7 molecules was obtained for the first time. A total of 27 transitions for (Li-6)2 and 3 transitions for Li6-Li-7 were observed; also 14 new Na2 transitions were observed. Transitions were observed in the range 5196-5889 A pumping with one of 7 single-mode argo ion laser lines in the 4579-5017

  16. Optically pumped cw semiconductor ring laser

    Microsoft Academic Search

    Erlich

    1983-01-01

    An optically pumped semiconductor ring laser having a plurality of reflective elements optically aligned with one another to form a ring-shaped resonant cavity. A semiconductor lasing medium is mounted within the ring-shaped resonant cavity by a transparent, heat conductive mount located within a vacuum\\/cooling chamber of the type which allows the passage of a laser beam therethrough. A pump beam

  17. Investigation of Fluctuations in - and Two - Dye Lasers

    Microsoft Academic Search

    Edward Charles Gage

    1989-01-01

    The intensity fluctuations of one- and two-mode dye lasers are investigated experimentally and theoretically, in the latter case by means of numerical integration of the equations of motion for the various laser models. Third -order theories appropriate for lasers not too far above threshold are augmented by an additive noise term to represent spontaneous emission and a multiplicative noise term

  18. Optofluidic dye laser in a foil.

    PubMed

    Vannahme, Christoph; Christiansen, Mads Brøkner; Mappes, Timo; Kristensen, Anders

    2010-04-26

    First order distributed feedback optofluidic dye lasers embedded in a 350 microm thick TOPAS((R)) foil are demonstrated. They are designed in order to give high output pulse energies. Microfluidic channels and first order distributed feedback gratings are fabricated in parallel by thermal nanoimprint into a 100 microm foil. The channels are closed by thermal bonding with a 250 microm thick foil and filled with 5.10(-3) mol/l Pyrromethene 597 in benzyl alcohol. The fluid forms a liquid core single mode slab waveguide of 1.6 microm height on a nanostructured grating area of 0.5 x 0.5 mm(2). This results in a large gain volume. Two grating periods of 185 nm and 190 nm yield single mode laser light emission at 566 nm and 581 nm respectively. High emitted pulse energies of more than 1 microJ are reported. Stable operation for more than 25 min at 10 Hz pulse repetition rate is achieved. PMID:20588775

  19. High resolution tuning system for pulsed dye lasers

    Microsoft Academic Search

    Alejandro A. Hnilo; Francisco A. Manzano; Oscar E. Martinez

    1991-01-01

    The mechanical requirements of a 0.15-pm wavelength-scan resolution in high-precision tuning multimode pulsed dye laser oscillators are presently satisfied by placing a prism at the minimum deviation angle in the dye laser cavity; it thereby acts as an optical reductor of the variation in the angle between the tuning mirror and the grating. Since the reduction factor varies with angle

  20. 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.

  1. Comparison of laser performance of dye molecules in sol-gel, polycom, ormosil, and poly(methyl methacrylate) host media.

    PubMed

    Rahn, M D; King, T A

    1995-12-20

    Laser performance is described for Rhodamine 590, Pyrromethene 567, Perylene red, and Perylene orange in inorganic porous sol-gel glass, poly(methyl methacrylate)(PMMA), a composite of porous sol-gel glass with PMMA and organically modified silicate ormosil glass. Lasers were excited with a flash-lamp-pumped dye laser in the long-pulse-length regime (3 µs, 506 nm, 300 mJ) and a second-harmonic Nd:YAG laser in the short-pulse-length regime (6 or 15 ns, 532 nm, 60 mJ). The feasibility of long-pulse-length operation is demonstrated, detailed characteristics of short-pulse operation are described, and laser damage measurements are given. The nonpolar perylene dyes had better performance in partially organic hosts, and the ionic rhodamine and pyrromethene dyes performed best in the inorganic sol-gel glass host. PMID:21068943

  2. Influence of energy transfer on fluorescence and lasing properties of various laser dyes co-doped in ORMOSILs

    NASA Astrophysics Data System (ADS)

    Su, Deliang; Yang, Yu; Qian, Guodong; Wang, Zhiyu; Wang, Minquan

    2004-10-01

    Laser dye perylene red (p-red) was co-doped with coumarin 440 (C440) and/or pyrromethene 567 (p567) into MTES-derived organically modified silicates (ORMOSILs) by sol-gel process. Energy transfer among C440, p567 and p-red has been observed. The fluorescence and lasing properties of such energy transfer dye lasers have been investigated. Improved laser efficiency of p-red and broad tunable range as wide as 60 nm were obtained. The effect of dye concentration on energy transfer, laser efficiency and tunable range were also discussed. With the presence of C440 and/or p567, the laser lifetime of p-red exceeded 45 000 pulses at pump intensity beyond 0.5 J/cm 2.

  3. Laser processing of nanocrystalline TiO2 films for dye-sensitized solar cells

    E-print Network

    Arnold, Craig B.

    Laser processing of nanocrystalline TiO2 films for dye-sensitized solar cells H. Kim,a) G. P­20 m thick) layers incorporated in dye-sensitized solar cells. Laser direct-write is a laser techniques to produce porous nc- TiO2 films required for dye-sensitized solar cells. The dye solar cells

  4. Scaling of diode-pumped Cs laser: transverse pump, unstable cavity, MOPA

    Microsoft Academic Search

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

    2010-01-01

    There has been recent interest in Diode Pumped Alkali Lasers (DPALs) and their scaling to higher powers. Scaling of DPALs to high powers requires using multiple pump sources such as laser diode arrays or stacks of arrays. Coupling of multiple pump beams into the laser gain medium can be realized using a transverse pumping scheme that is most efficient for

  5. Linear and cross-linked polymeric solid-state dye lasers based on 8-substituted alkyl analogues of pyrromethene 567

    NASA Astrophysics Data System (ADS)

    Álvarez, M.; Amat-Guerri, F.; Costela, A.; García-Moreno, I.; Gómez, C.; Liras, M.; Sastre, R.

    2005-06-01

    The lasing properties of analogues of the commercial laser dye pyrromethene 567 (PM567) incorporated (dissolved or copolymerized) into polymeric matrices have been studied using both linear and cross-linked methyl methacrylate-based copolymers with different degrees of functionalization. All synthesized dyes have the chromophore core of PM567 but with an ?-acyloxypolymethylene chain at position 8. In general, the new materials exhibited laser emission with higher efficiencies and much higher photostabilities than those containing the commercial dye PM567 under the same experimental conditions. Lasing efficiencies of up to 40% were obtained under transversal pumping at 534 nm. The highest photostabilities, with the laser output remaining stable or dropping by less than 15% after 100 000 pump pulses at the same position of the sample, were reached in cross-linked materials with dyes covalently linked to the polymeric chains. When the polymeric samples were incorporated into a grazing-incidence grating oscillator, narrow-line-width operation with tuning ranges of up to 40 nm was obtained. These results show that efficient and photostable solid-state dye lasers competitive with their liquid counterparts can be developed by adequate chemical modifications in the dye molecules, as well as by the selection of appropriate polymeric formulations.

  6. Research on solar pumped liquid lasers

    Microsoft Academic Search

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

    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

  7. Research on solar pumped liquid lasers

    Microsoft Academic Search

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

    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

  8. Optically pumped CW semiconductor ring laser

    Microsoft Academic Search

    M. M. Salour; A. Fuchs; D. Debelaar

    1986-01-01

    An optically pumped semiconductor ring laser is described which consists of: a ring-shaped resonant cavity defined by a plurality of optically aligned reflective elements, one of the reflective elements being partially transmissive in order to permit the passage of a laser beam therethrough; a semiconductor lasing medium mounted within the ring-shaped resonant cavity; means for the semiconductor lasing medium within

  9. Diode pumped alkali vapor fiber laser

    Microsoft Academic Search

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

    2007-01-01

    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

  10. Diode pumped alkali vapor fiber laser

    Microsoft Academic Search

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

    2006-01-01

    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

  11. Electron beam pumped tunable excimer lasers

    Microsoft Academic Search

    M. C. Smayling

    1981-01-01

    Laser characteristics of the broadband rare gas halide Xe2Ce, Kr2F, and XeF (C yields A) were investigated. Since all three excimers have unbound ground states, a spectrally wide emission bandwidth is available for wavelength tuning. Other excimers with wide band fluorescence emissions were studied but had gains too small to achieve laser threshold in a 10 cm transversely pumped laser

  12. Robust integrated optofluidic-ring-resonator dye lasers.

    PubMed

    Sun, Yuze; Suter, Jonathan D; Fan, Xudong

    2009-04-01

    We demonstrate a robust optofluidic dye laser that integrates fluidics with a high Q-factor ring resonator. In this optofluidic laser the ring resonator is formed by an optical fiber fused on the inner surface of a glass capillary serving as a fluidic channel. Laser oscillation is achieved with a threshold of 7 microJ/mm2 per pulse. Furthermore, the laser emission can be directionally outcoupled through a fiber prism for easy and efficient light delivery. PMID:19340213

  13. Diode Pumped Alkali Lasers: History, current state and perspectives

    Microsoft Academic Search

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

    2011-01-01

    emission. However, the real interest to alkali vapor lasers appeared after the first demonstration in 2003 [2] of a really efficient lasing in Rb vapor optically pumped by Ti:Sapphire laser. This interest was stimulated by a possibility of using efficient diode lasers for pumping of alkali vapors that promised a very high total wall plug efficiency Diode Pumped Alkali Laser

  14. Millennia V Diode-Pumped, CW Visible Laser

    E-print Network

    Kleinfeld, David

    Millennia V Diode-Pumped, CW Visible Laser User's Manual The Solid-State Laser Company 1335 Terra your Millennia® V diode-pumped, continu- ous-wave, visible laser. The system comprises four elements. #12;Millennia V Diode-Pumped, CW Visible Laser iv Finally, if you encounter any difficulty

  15. Singlet oxygen and dye-triplet-state quenching in solid-state dye lasers consisting of pyrromethene 567-doped poly(methyl methacrylate).

    PubMed

    Ahmad, M; Rahn, M D; King, T A

    1999-10-20

    Solid-state dye lasers based on poly(methyl methacrylate) (PMMA) doped with Pyrromethene 567 dye (P567) have been investigated. The preparation techniques employed provided high photostability and laser damage threshold for P567 in pure PMMA with 270,000 pulses emitted before the conversion efficiency fell to half its initial value for a pump fluence of 0.16 J cm(-2). When PMMA was modified with 1, 4-diazobicyclo [2, 2, 2] octane singlet oxygen quencher, the longevity increased to 550,000 pulses, corresponding to a normalized photostability of 270 GJ mol(-1). Modification of PMMA with a triplet quencher (perylene) yielded no improvement, but in ethanol solutions both additives enhanced photostability. It is possible that in PMMA, stabilization by means of triplet quenching that depends on dye diffusion is prevented but that stabilization by means of singlet oxygen quenching that depends on the faster oxygen diffusion rate will succeed. PMID:18324161

  16. 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.

  17. 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.

  18. Solar pumped, alkali vapor laser

    Microsoft Academic Search

    David Ham; Mark A. Defaccio

    1987-01-01

    High power lasers based in space have been considered as sources for power transmission, laser propulsion, materials processing and space defense. The feasibility of such systems is based on the cost per unit power delivered, with detailed studies indicating that light weight has a greater impact on cost than laser efficiency. Solar radiation is a natural source of power for

  19. Laser photolysis of fluorone dyes in a chitosan matrix

    SciTech Connect

    Slyusareva, E A; Sizykh, A G; Gerasimova, M A; Slabko, V V; Myslivets, S A

    2012-08-31

    Kinetics of laser-induced photobleaching of fluorone dyes (fluorescein, dibromofluorescein, eosin Y, erythrosin B, Rose Bengal) is studied in a chitosan matrix. For all dyes the bleaching kinetics at the intensities of laser radiation 0.7 - 11.9 W cm{sup -2} demonstrates quasi-monomolecular behaviour. The results are analysed using a kinetic model, based on the four-level (S{sub 0}, S{sub 1}, T{sub 1}, T{sub n}) scheme of the dye with chemically active triplet states taken into account. It is shown that the rate constants of the chemical reaction involving higher triplet states in the dyes studied amount to (3.9 - 18.6) Multiplication-Sign 10{sup 6} s{sup -1} and exceed the analogous values for the reaction involving the first lower triplet states by nine orders of magnitude. The rate of reaction involving the first triplet states appeared to be higher by one - two orders of magnitude than that in the case of higher triplet states involved because of low population of the latter. The possible mechanism of dye bleaching with participation of chitosan that consists in reduction of the dye to the leuco form by transfer of hydrogen from the chitosan matrix is discussed. (interaction of laser radiation with matter. laser plasmas)

  20. Pumping of atomic alkali lasers by photoexcitation of a resonance line blue satellite and alkali-rare gas excimer dissociation

    Microsoft Academic Search

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

    2009-01-01

    Photoassociation of alkali-rare gas atomic collision pairs provides an alternative approach to optically pumping atomic alkali lasers. Lasing on the 6 2P1\\/2-->6 2S1\\/2 (D1) transition of Cs has been observed when the blue satellite of the 6 2P3\\/2<--6 2S1\\/2 (D2) transition, peaking at ~837 nm for mixtures of Cs vapor, Ar, and ethane, is pumped by a pulsed dye laser.

  1. Preparation of 6-hydroxyindolines and their use for preparation of novel laser dyes

    DOEpatents

    Field, G.F.; Hammond, P.R.

    1993-10-26

    A novel method is described for the synthesis of 6-hydroxyindolines and new fluorescent dyes produced therefrom, which dyes are ring-constrained indoline-based rhodamine class dyes. These dyes have absorption and emission spectra which make them particularly useful in certain dye laser applications.

  2. 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.

  3. Uniformity of pump intensity distribution in diode-array side-pumped laser rod

    NASA Astrophysics Data System (ADS)

    Liu, Wenwen; Niu, Yanxiong; Liu, Haixia; Wang, Caili; Niu, Haisha; Man, Da

    2014-11-01

    Diode-pumped solid-state lasers are high efficiency, long lifetime, compact and reliable, so they have been covering a wide range of applications. Thermal effect is a major limiting factor in scaling the average power of high-power solid-state lasers, so it is a critical issue in designing diode-pumped solid-state lasers. The uniform pump intensity distribution in laser rod can weaken the influence of thermal effects in laser, and the research of improving the pump distribution uniformity has attracted a great deal of attention. People usually establish a model of single diode-bar pumped laser rod to calculate the distribution. However, for diode-array pumped high-power lasers, the model is limited and has deviation with the actual pump distribution, which cannot reflect the real working conditions in the laser. In this paper, the theoretical model of diode-array pumped laser rod is built. Based on the actual working environment of diode-array side-pumped Tm:YAG laser rod, the expression of pump intensity distribution in the laser medium is deduced. Additionally, the influence of total pump power, pump structure, Tm:YAG rod characteristic parameters and pump beam radius on pump intensity distribution are simulated and analyzed. Moreover, the parameters are optimized in order to obtain the optimistic results which are efficient to improve the uniformity of pump distribution. The results show that when the pumping distance from diode-array to the rod's surface is 3mm, the distance between two rows of diode-bars is 1mm, the absorption coefficient is 330m-1,the pump beam width is 2.5mm,the pump intensity distribution of five-way pumped laser rod is improved, and then the thermal effects could be weakened. The presented results can provide theoretical guidance to design and optimization of high-power lasers.

  4. Polymer photonic crystal dye lasers as label free evanescent cell sensors

    NASA Astrophysics Data System (ADS)

    Christiansen, Mads B.; Lopacinska, Joanna M.; Jakobsen, Mogens H.; Mortensen, Niels A.; Dufva, Martin; Kristensen, Anders

    2009-08-01

    Dye doped polymer photonic crystal band edge lasers are applied for evanescent wave sensing of cells. The lasers are rectangular shaped slab waveguides of dye doped polymer on a glass substrate, where a photonic crystal is formed by 100 nm deep air-holes in the surface of the 375 nm high waveguides. The lasers are fabricated by combined nanoimprint and photolithography (CNP) in Ormocore hybrid polymer doped with the laser dye Pyrromethene 597. The lasers emit in the chip plane at a wavelength around 595 nm when pumped with 5 ns pulses from a compact frequency doubled Nd:YAG laser. We investigate the sensitivity of photonic crystal band-edge lasers to partial coverage with HeLa cells. The lasers are chemically activated with a flexible UV activated anthraquinone based linker molecule, which enables selective binding of cells and molecules. When measuring in Phosphate Buffered Saline (PBS), which has a refractive index close to that of the cells, the emission wavelength depends linearly on the cell density on the sensor surface. Our results demonstrate that nanostructured hybrid polymer lasers, which are cheap to fabricate and very simple to operate, can be selectively chemically activated with UV sensitive photolinkers for further bioanalytical applications. This opens the possibility to functionalize arrays of optofluidic laser sensors with different bio-recognition molecules for multiplexed sensing. The linear relationship between cell coverage and wavelength indicates that the slight refractive index perturbation from the partial coverage of the sensor influences the entire optical mode, rather than breaking down the photonic crystal feedback.

  5. A Modular Control Platform for a Diode Pumped Alkali Laser

    Microsoft Academic Search

    J. Shapiro; S. Teare

    2008-01-01

    Many of the difficulties of creating compact, high power laser systems can be overcome if the heat dissipating properties of chemical lasers can be combined with the efficiency of diode lasers. Recently, the novel idea of using solid state diode lasers to pump gaseous gain media, such as is done in diode pumped alkali lasers (DPALs), has been proposed and

  6. Linewidth characteristics of Raman-shifted dye laser output at 720 and 940 nm

    NASA Technical Reports Server (NTRS)

    Grossmann, B. E.; Singh, U. N.; Cotnoir, L. J.; Wilkerson, T. D.; Higdon, N. S.; Browell, E. V.

    1986-01-01

    Raman conversion efficiency and line broadening are reported for Stokes operation at 720 and 940 nm, with hydrogen and deuterium as the Raman source, and using an Nd:YAG pumped Quanta-Ray PDL-2 dye laser. The dye laser linewidth is 0.2/cm (FWHM) with the grating alone as an intracavity element, and the conversion efficiency at 400 psi was found to be 40 and 20 percent for outputs of 720 and 940 nm, respectively. Pressure broadening coefficients of (9.2 + or - 0.9) x 10 to the -5th per cm/psi for hydrogen, and 7.7 x 10 to the -5th per cm/psi for deuterium, were obtained in good agreement with previous results. The linewidth at the first Stokes wavelength was shown to be determined by pressure broadening in the Raman medium.

  7. Solid-state dye lasers based on polymethyl methacrylate modified with methanol

    NASA Astrophysics Data System (ADS)

    Jiang, Y. G.; Fan, R. W.; Xia, Y. Q.; Chen, D. Y.

    2011-02-01

    Solid-state dye samples based on modified polymethyl methacrylate with methanol (MPMMA) doped with pyrromethene 567 (PM567) were first prepared. The effects of volume percentage of methanol on the laser performances of the samples, including spectra properties, slope efficiency and photostability were studied. The highest slope efficiency 66.39% was obtained in the sample (MMA:methanol = 16:4). Pumping the samples at a repetition rate of 5 Hz with a pulse energy as high as 100 mJ (the fluence was 0.26 J/cm2), the output energy dropped to half of its initial value after approximate 156720 shots and the corresponding normalized photostability reached 101.86 GJ/mol in the sample (MMA:methanol = 17:3). Our results indicate that it can obtain a high slope efficiency and good photostability for a solid-state dye laser using MPMMA as solid hosts.

  8. UV laser interaction with a fluorescent dye solution studied using pulsed digital holography.

    PubMed

    Amer, Eynas; Gren, Per; Sjödahl, Mikael

    2013-10-21

    A frequency tripled Q-switched Nd-YAG laser (wavelength 355 nm, pulse duration 12 ns) has been used to pump Coumarin 153 dye solved in ethanol. Simultaneously, a frequency doubled pulse (532 nm) from the same laser is used to probe the solvent perpendicularly resulting in a gain through stimulated laser induced fluorescence (LIF) emission. The resulting gain of the probe beam is recorded using digital holography by blending it with a reference beam on the detector. Two digital holograms without and with the pump beam were recorded. Intensity maps were calculated from the recorded digital holograms and used to calculate the gain of the probe beam due to the stimulated LIF. In addition numerical data of the local temperature rise was calculated from the corresponding phase maps using Radon inversion. It was concluded that about 15% of the pump beam energy is transferred to the dye solution as heat while the rest is consumed in the radiative process. The results show that pulsed digital holography is a promising technique for quantitative study of fluorescent species. PMID:24150372

  9. Dye-sensitized solar cells using laser processing techniques

    Microsoft Academic Search

    Heungsoo Kim; Alberto Pique; Gary P. Kushto; Raymond C. Y. Auyeung; S. H. Lee; Craig B. Arnold; Zakia H. Kafafi

    2004-01-01

    Laser processing techniques, such as laser direct-write (LDW) and laser sintering, have been used to deposit mesoporous nanocrystalline TiO2 (nc-TiO2) films for use in dye-sensitized solar cells. LDW enables the fabrication of conformal structures containing metals, ceramics, polymers and composites on rigid and flexible substrates without the use of masks or additional patterning techniques. The transferred material maintains a porous,

  10. Adverse effects associated with the 577- and 585-nanometer pulsed dye laser in the treatment of cutaneous vascular lesions: A study of 500 patients

    Microsoft Academic Search

    Vicki J. Levine; Roy G. Geronemus

    1995-01-01

    Background:The flashlamp-pumped pulsed dye laser has been used in the treatment of cutaneous vascular disorders since 1986. Although this laser is now widely used for the treatment of port-wine stains, telangiectases, and hemangiomas, the incidence of adverse reactions has not been clearly defined in a large series of patients.

  11. Optical resolution beyond the natural linewidth: A level-crossing experiment on the 32 P 3\\/2 level of sodium using a tunable dye laser

    Microsoft Academic Search

    H. Figger; H. Walther

    1974-01-01

    A level crossing experiment on the hyperfine structure of the 32 P 3\\/2 level of Na23 was performed using a nitrogen laser pumped dye laser for the excitation of the Na atoms. The fluorescent light was observed in time intervals which were initiated up to seven lifetimes after excitation. Therefore the signal was only determined by atoms having survived in

  12. High-energy transversely pumped alkali vapor laser

    Microsoft Academic Search

    J. Zweiback; A. Komashko

    2011-01-01

    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

  13. Free-running emerald laser pumped by laser diode

    Microsoft Academic Search

    Zhenqiang Chen; Ge Zhang

    2006-01-01

    Free-running emerald laser pumped by 660-nm laser diode (LD) was reported. Free-running output power of 24 mW has been obtained with overall efficiency of 1.4% and slope efficiency of 11.9% when the LD incident power was 2.56 W. The laser threshold value of emerald crystal was estimated to be 0.7 W.

  14. Free-running emerald laser pumped by laser diode

    NASA Astrophysics Data System (ADS)

    Chen, Zhenqiang; Zhang, Ge

    2006-11-01

    Free-running emerald laser pumped by 660-nm laser diode (LD) was reported. Free-running output power of 24 mW has been obtained with overall efficiency of 1.4% and slope efficiency of 11.9% when the LD incident power was 2.56 W. The laser threshold value of emerald crystal was estimated to be 0.7 W.

  15. Optimization algorithm for the pump structure of diode side-pumped lasers

    Microsoft Academic Search

    Changqing Cao; Xiaodong Zeng; Yuying An

    2008-01-01

    The pump structure greatly influences the characteristics of a diode side-pumped laser. To achieve high absorption efficiency and a homogeneous pump-beam distribution simultaneously, a systemic algorithm has been established to optimize the pump structure, where multiple reflections occur on the internal wall of the reflector inside the pump chamber. The absorption efficiency and the deviation of the absorption distribution are

  16. 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.

  17. Advanced diode-pumped alkali lasers

    Microsoft Academic Search

    B. V. Zhdanov; R. J. Knize

    2008-01-01

    In this review we present the analysis of optically pumped alkali lasers research and development from their first proposal in 1958 to the current state. Main achievements and problems existing in this field of research are discussed and possible solutions of the problems are proposed. Detailed description of the most important experiments and their results are presented. We have tried

  18. Optically pumped distributed feedback dye lasing with slide-coated TiO? inverse-opal slab as Bragg reflector.

    PubMed

    Han, Sung Gu; Lim, Jongchul; Shin, Jinsub; Lee, Sung-Min; Park, Taiho; Yoon, Jongseung; Woo, Kyoungja; Lee, Hyunjung; Lee, Wonmok

    2014-08-15

    We demonstrate an optical amplification of organic dye within a TiO2 inverse-opal (IO) distributed feedback (DFB) reflector prepared by a slide-coating method. Highly reflective TiO2 IO film was fabricated by slide coating the binary aqueous dispersions of polystyrene microspheres and charge-stabilized TiO2 nanoparticles on a glass slide and subsequently removing the polymer-opal template. TiO2 IO film was infiltrated, in turn, with the solutions of DCM, a fluorescent dye in various solvents with different indices of refraction. Optical pumping by frequency-doubled Nd:YAG laser resulted in amplified spontaneous emission in each dye solution. In accordance with the semi-empirical simulation by the FDTD method, DCM in ethanol showed the best emission/stopband matching for the TiO2 IO film used in this study. Therefore, photo excitation of a DCM/ethanol cavity showed a single-mode DFB lasing at 640 nm wavelength at moderate pump energy. PMID:25121863

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

    SciTech Connect

    Hwang, I.H. (Hampton Univ., VA (United States). Dept. of Physics); Lee, J.H. (National Aeronautics and Space Administration, Hampton, VA (United States). 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.

  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. Longitudinally pumped pulsed Ti:S laser

    NASA Astrophysics Data System (ADS)

    Liu, Hongfa; Yan, Baisheng; Lei, Hairong; Zhang, Guowei; Chen, Qinghan

    1996-09-01

    Our pulsed Ti:S laser is abaxial longitudinally pumped by a frequency double YAG laser with VRM unstable resonator, the Ti:S crystal is Bi-Brewster-cutting. The single output energy of the Ti:S laser is over 130 mJ at 1 Hz and over 110 mJ at 10 Hz, the efficiency is 39.6% and 36. 7% respectively, the tunable range is 0.723 approximately 0.996 micrometers with only a pair of flat mirrors, the output energy in the two ends is 1/10 of that in the center wavelength. We discuss the effect of choice of the crystal size, the angle (alpha) (between the pump beam and the cavity axis) on efficiency. We suggest that the high absorptivity, high FOM value of the crystal bring high output and high efficiency when longitudinally pumped by a flat-top laser beam. We also show the scheme of our Ti:S laser and our broad band transmitted curve of reflective mirror.

  2. 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.

  3. 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.

  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. Optical Amplification in Organic Dye-doped Polymeric Channel Waveguide under CW Optical Pumping

    Microsoft Academic Search

    Kenichi Yamashita; Kengo Hase; Hisao Yanagi; Kunishige Oe

    2007-01-01

    We have achieved amplified spontaneous emission and optical amplification in an organic dye-doped polymeric waveguide using a cw pumping source. By fabricating a channel waveguide structure, amplified spontaneous emission was found under long-pulse (0.3-4.1 ms) optical pumping with 120 mW amplitude from the waveguide end face. The optical gain for externally input 770 nm light was measured to be 13.8

  6. Comparison of the performance of photonic band-edge liquid crystal lasers using different dyes as the gain medium

    NASA Astrophysics Data System (ADS)

    Mowatt, Carrie; Morris, Stephen M.; Song, Myoung Hoon; Wilkinson, Timothy D.; Friend, Richard H.; Coles, Harry J.

    2010-02-01

    The primary concern of this work is to study the emission characteristics of a series of chiral nematic liquid crystal lasers doped with different laser dyes (DCM, pyrromethene 580, and pyrromethene 597) at varying concentrations by weight (0.5-2 wt %) when optically pumped at 532 nm. Long-wavelength photonic band-edge laser emission is characterized in terms of threshold energy and slope efficiency. At every dye concentration investigated, the pyrromethene 597-doped lasers exhibit the highest slope efficiency (ranging from 15% to 32%) and the DCM-doped lasers the lowest (ranging from 5% to 13%). Similarly, the threshold was found to be, in general, higher for the DCM-doped laser samples in comparison to the pyrromethene-doped laser samples. These results are then compared with the spectral properties, quantum efficiencies and, where possible, fluorescence lifetimes of the dyes dispersed in a common nematic host. In accordance with the low thresholds and high slope efficiencies, the results show that the molar extinction coefficients and quantum efficiencies are considerably larger for the pyrromethene dyes in comparison to DCM, when dispersed in the liquid crystal host.

  7. High pulse energy output from tunable solid-state dye laser based on MPMMA doped with PM567

    NASA Astrophysics Data System (ADS)

    Fan, R. W.; Jiang, Y. G.; Xia, Y. Q.; Chen, D. Y.

    2011-04-01

    Tunable solid-state dye laser sample based on modified polymethyl methacrylate (MPMMA) with methanol co-doped with pyrromethene 567 (PM567) and Coumarin 440 (C440) was prepared. Tunable dye laser output wavelength from 546 to 594 nm was obtained in an oscillator-amplifier configuration. With the input seed laser energy being about 1.5 mJ, the highest dye laser output energy reached 113.9 mJ, and the corresponding conversion slope efficiency was 51.39%. To the best of our knowledge, the tuning range and narrow linewidth dye output energy is the best under the same condition so far. The linewidth for the seed laser and amplified laser were measured with the result of less than 0.2 nm. With the amplified medium being pumped at a repetition rate of 10 Hz with a pulse energy as high as 120 mJ (the fluence was 0.42 J/cm2), the laser output energy dropped to half of its initial value after approximate 43000 pulses.

  8. Revisiting of LED pumped bulk laser: first demonstration of Nd:YVO? LED pumped laser.

    PubMed

    Barbet, Adrien; Balembois, François; Paul, Amandine; Blanchot, Jean-Philippe; Viotti, Anne-Lise; Sabater, Jacques; Druon, Frédéric; Georges, Patrick

    2014-12-01

    We describe here what is, to the best of our knowledge, the first LED pumped Nd:YVO? laser. Near-IR LED arrays with a wavelength centered close to 850 nm were used to pump transversely the crystal. By pulsing LEDs, with a duration of the order of the laser transition lifetime, we obtained sufficient pump intensities to reach the laser threshold. At a frequency of 250 Hz, we obtained an output energy of 40 ?J at 1064 nm for an input pump energy of 7.4 mJ, which corresponds to an optical efficiency of 0.5%. Experimental results of small signal gain are compared with theoretical analysis. PMID:25490664

  9. 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 ?s 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 discussed.

  10. A hybrid laser system consisting of a frequency-doubled, narrow-line-width, distributed-feedback dye laser oscillator and a high saturation-fluence Ce:LiCaAlF6 crystal amplifier

    NASA Astrophysics Data System (ADS)

    Hoa, D. Q.; Hung, N. D.; Moroe, J.; Takeyasu, N.; Imasaka, T.

    2003-05-01

    A tunable narrow-band picosecond dye laser emitting in the ultraviolet region was amplified using a Ce:LiCaAlF6 crystal pumped by the fourth-harmonic emission of a Nd:Y3Al5O12 laser. The single-pass gain obtained exceeded 2 in the spectral range of 288 to 297 nm.

  11. 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.

  12. Pulsed dye laser diagnostics of vacuum arc cathode spots

    Microsoft Academic Search

    AndrC Anders; Simone Anders; Burkhard Juttner; Woldemar Botticher; Harald Luck; Gerald Schroder

    1992-01-01

    The ignition and arc phases of vacuum arcs were investigated using differential dye laser absorption photography with simultaneous high spatial (micrometer) and temporal (nanosecond) resolution. The discharge duration was 800 ns, the current 50-150 A, the electrode material copper, and the cathode-anode distance less than 50 ?m. A 0.4 ns laser pulse (tunable, ?=480-530 nm) was used to obtain momentary

  13. Efficient tunable near-infrared solid-state dye laser with good beam quality

    NASA Astrophysics Data System (ADS)

    Russell, Jeffrey A.; Pacheco, Dennis P.; Aldag, Henry R.

    2005-04-01

    We have demonstrated a laser-pumped, near-infrared solid-state dye laser (SSDL) with a slope efficiency approximately equal to 35%, tunability over approximately equal to 40 nm (from 710 to 750 nm) and M2 < 1.3. This device utilizes a folded three-mirror resonator containing a tight focus for the gain medium and a collimated section for the tuning element. The folded cavity is astigmatically compensated through proper choice of sample thickness and cavity fold angle. We achieved low-threshold operation through the tight intracavity focus and by mounting the sample at Brewster"s angle. Two pump lasers were used in this study: (1.) a flashlamp-pumped dye laser (FPDL) with an output wavelength of 630 nm and a pulse duration of approximately equal to 1 microsecond; and (2.) a pulsed red diode laser with an output wavelength of 671 nm and a pulse duration of approximately equal to 200 ns. The gain medium consists of the near-infrared dye Oxazine 725 in the solid host modified PMMA. With the FPDL as the pump source, slope efficiencies up to approximately equal to 35% were measured at the center of the tuning range. A single-plate birefringent filter (BRF) was used to tune the output from approximately equal to 710 to 750 nm with a single output wavelength. The BRF narrowed the spectral output from approximately equal to 15 to approximately equal to 0.8 nm, and provided smooth, continuous tuning over the 40-nm range. Lasing was observed outside this range, but the output consisted of two wavelengths separated by approximately equal to 50 nm (the free spectral range of the BRF). Time-resolved data showed that, for these cases, the laser switches from the shorter to the longer wavelength during the pulse. Input/output curves were generated as a function of resonator feedback for several output wavelengths. Findlay-Clay analyses were used to determine the round-trip cavity loss at each wavelength. The results correlate well with known losses in the resonator, including dye self-absorption losses. Beam-quality measurements were made near the peak of the tuning curve (lambda approximately equal to 727 nm) with a cavity feedback of 95%. At 1.5x threshold, the laser output had an M2 value of approximately equal to 1.06. At 7x threshold, the beam quality degraded slightly to M2 approximately equal to 1.26. Good temporal tracking was observed between the pump and output pulses, once the SSDL turned on. With design improvements to reduce the threshold, the tunable SSDL was also lased using the diode laser as the pump source. Further characterization of this device under direct diode-pumping is in process.

  14. Laser sintering of photoelectrode layers for Dye Solar Cell technology

    Microsoft Academic Search

    G. Mincuzzi; L. Vesce; R. Riccitelli; A. Reale; A. Di Carlo; T. M. Brown

    2009-01-01

    Scanning laser processing has become a useful and often used tool in thin film solar cell industries, since it enables precise, low cost, non-contact and highly automated fabrication processes such as scribing, patterning, marking, edge deletion, local melting and sintering. Dye solar cells (DSCs) are electrochemical photovoltaic devices representing an attractive technology for large area solar energy conversion since they

  15. Chirp in a mode-locked ring dye laser

    Microsoft Academic Search

    J. J. Fontaine; J.-C. Diels

    1983-01-01

    Dietel et al. (1982) have shown that an intracavity prism is not necessarily detrimental to the generation of ultrashort pulses in a mode-locked dye laser. The present investigation is concerned with measurements of pulse compression which were performed for intracavity and extracavity conditions, taking into account a demonstration of the role of glass dispersion. The suggestion is made that a

  16. Dye-laser fluctuations: Comparison of colored loss-noise and white gain-noise models

    SciTech Connect

    Aguado, M.; Hernandez-Garcia, E.; San Miguel, M.

    1988-12-01

    A single-mode dye-laser model incorporating pump white noise through gain-parameter fluctuations is analyzed. It includes a fluctuating saturation term. Intensity fluctuations, a first-order-like transition, and intensity correlation functions are calculated and discussed. It is found that effects previously claimed to be a consequence of the presence of colored noise in the context of loss-noise models can be also explained by white gain noise, except for the existence of two time regimes in the early decay of intensity correlation functions.

  17. Influence of various coumarin dyes on the laser performance of laser dyes co-doped into ORMOSILs

    NASA Astrophysics Data System (ADS)

    Yang, Y.; Zou, J.; Rong, H.; Qian, G. D.; Wang, Z. Y.; Wang, M. Q.

    2007-01-01

    Several kinds of coumarin dyes (C440, C460, C500, C503 and C540A) were co-doped with perylene red (p-red) or pyrromethene 567 (p567) into VTES- and MTES-derived organically modified silicates (ORMOSILs) respectively, by the sol-gel process. The effects of coumarin dyes and their concentration on the laser properties and photostabilities of p-redand p567 were studied and the mechanisms involved were discussed. At optimized coumarin dye concentration, the slope efficiency of co-doped p-redincreased by a factor of 2 while only minor increases in the laser efficiency of p567 were observed. A broader tunable range with increased conversion efficiency and at least a 3-fold improvement in the photostabilities of p-redand p567 in the presence of coumarin family dyes have also been achieved. The mechanism responsible for the improvement in the laser performances and photostabilities of p-redand p567 resulted from the energy transfer between p-red/567 and coumarin dyes.

  18. Dye-sensitized solar cells using laser processing techniques

    NASA Astrophysics Data System (ADS)

    Kim, Heungsoo; Pique, Alberto; Kushto, Gary P.; Auyeung, Raymond C. Y.; Lee, S. H.; Arnold, Craig B.; Kafafi, Zakia H.

    2004-07-01

    Laser processing techniques, such as laser direct-write (LDW) and laser sintering, have been used to deposit mesoporous nanocrystalline TiO2 (nc-TiO2) films for use in dye-sensitized solar cells. LDW enables the fabrication of conformal structures containing metals, ceramics, polymers and composites on rigid and flexible substrates without the use of masks or additional patterning techniques. The transferred material maintains a porous, high surface area structure that is ideally suited for dye-sensitized solar cells. In this experiment, a pulsed UV laser (355nm) is used to forward transfer a paste of commercial TiO2 nanopowder (P25) onto transparent conducting electrodes on flexible polyethyleneterephthalate (PET) and rigid glass substrates. For the cells based on flexible PET substrates, the transferred TiO2 layers were sintered using an in-situ laser to improve electron paths without damaging PET substrates. In this paper, we demonstrate the use of laser processing techniques to produce nc-TiO2 films (~10 ?m thickness) on glass for use in dye-sensitized solar cells (Voc = 690 mV, Jsc = 8.7 mA/cm2, ff = 0.67, ? = 4.0 % at 100 mW/cm2). This work was supported by the Office of Naval Research.

  19. Enhancement of pump efficiency of a visible wavelength organic distributed feedback laser by resonant optical pumping.

    PubMed

    Ge, Chun; Lu, Meng; Tan, Yafang; Cunningham, Brian T

    2011-03-14

    A 22× reduction in laser pump threshold and a 23× enhancement in energy conversion have been demonstrated on a second order distributed feedback (DFB) laser using a resonant optical pumping (ROP) technique. The ROP scheme couples the excitation light into a distinct resonant mode of the laser cavity through the illuminating at a specific resonant incident angle. Coupling excitation light into the resonant mode results in an enhanced near-field, which significantly increases pump absorption by the active medium. Consequently, high power conversion efficiency between pumping light and lasing emission is achieved and laser pump threshold power is reduced. PMID:21445143

  20. Levitated droplet dye laser: a new approach for single molecule detection

    NASA Astrophysics Data System (ADS)

    Azzouz, H.; Alkhafadiji, L.; Balslev, S.; Johansson, J.; Mortensen, N. A.; Nilsson, S.; Kristensen, A.

    2006-02-01

    We present the first observation, to our knowledge, of lasing from a levitated, dye droplet. The levitated droplets are created by computer controlled pico-liter dispensing into one of the nodes of a standing ultrasonic wave (100 kHz), where the droplet is trapped. The free hanging droplet forms a high quality optical resonator, which shape can be externally controlled by the ultrasonic field, yielding wavelength tunability and directional control of the emission. Our 700 nL lasing droplets consist of Rhodamine 6G dissolved in ethylene glycol, at a concentration of 0.02 M. In our experiments the droplets are optically pumped at 532 nm light from a pulsed, frequency doubled Nd:YAG laser, and the dye laser emission is analyzed by a fixed grating spectrometer. With this setup we have achieved reproducible lasing spectra in the wavelength range 610 nm - 650 nm. The lasing spectra can controllably be modulated by shaping the droplet. Lasing micro-droplets have been demonstrated earlier, where the droplets in free fall passed the pumping laser beam. The levitated droplet technique has successfully been applied for a variety of bio-analytical applications at single cell level. In combination with the lasing droplets, the capability of this high precision setup can further be applied to create a highly sensitive intra cavity absorbance detection system.

  1. Laser Wakefield acceleration with high relativistic pumps

    SciTech Connect

    Katsouleas, T.; Mori, W.B. (University of California at Los Angeles, Los Angeles, CA 90024 (US)); Darrow, C.B. (Lawrence Livermore National Laboratory, Livermore, CA 94550 (US))

    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

  2. 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.

  3. 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.

  4. 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 ?s, 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.

  5. Solid-state lasers based on copolymers of methyl methacrylate and 2-hydroxyethyl acrylate doped with pyrromethene 567 dye

    NASA Astrophysics Data System (ADS)

    Chen, D. Y.; Jiang, Y. G.; Fan, R. W.; Peng, H.; Xia, Y. Q.

    2009-05-01

    Solid-state dye laser samples based on copolymers of methyl methacrylate (MMA) and 2-hydroxyethyl acrylate (HEA) doped with pyrromethene 567(PM567) were prepared. The highest slope efficiency 46.4% was obtained. With pump repetition rate of 10 Hz and intensity of 0.1 J/cm2, the output energy of the sample based on P (MMA: HEA 16:4) remained up to 82.10% of its initial value after approximate 100000 shots. To our knowledge, the achieved photostability is the best under the same condition so far. Compared with the sample based on the monopolymer, the slope efficiency and photostability of copolymer-based solid-state dye samples were both enhanced. The results indicate that the high laser performance using solid-state dye samples based on copolymers of MMA with HEA as solid hosts can be achieved.

  6. Photostability enhancement of Pyrromethene 567 and Perylene Orange in oxygen-free liquid and solid dye lasers.

    PubMed

    Rahn, M D; King, T A; Gorman, A A; Hamblett, I

    1997-08-20

    We investigated the effect of oxygen on the photostability of the laser dyes Pyrromethene 567, Perylene Orange, and Rhodamine 590 by determining their longevity of laser operation when pumped by the second harmonic of aQ -switched Nd:YAG laser. In solution, dissolved oxygen accelerated the photodegradation of Pyrromethene 567 and Perylene Orange but not Rhodamine 590. The photostability of Pyrromethene 567 was also found to be dependent on the solvent and on the lifetime of singlet oxygen. Deoxygenated Pyrromethene 567 doped polycom glass and modified poly(methyl methacrylate) (MPMMA) samples were tested for longevity of laser operation. A factor of 6 improvement in photostability was found for Pyrromethene 567 in MPMMA upon deoxygenation, and the total absorbed energy per mole of dye molecules to one-half output pulse energy was 36 GJ mol-1 . PMID:18259419

  7. Solid state organic laser emission at 970 nm from dye-doped fluorinated-polyimide planar waveguides

    Microsoft Academic Search

    Shun Yuyama; Takahiro Nakajima; Kenichi Yamashita; Kunishige Oe

    2008-01-01

    We have demonstrated near-infrared amplified spontaneous emission and laser emission from fluorinated-polyimide waveguides doped with an organic dye, 5,6-dichloro-2[8-(p-dimethylaminophenyl)-2,4-neopentylene-1,3,5,7-octatetraenyl]-3-ethylbenzothiazolium perchlorate (LDS950). The planar waveguides doped with 1 wt % of the dye, 10 mm in length and 9.3 mum in thickness, have exhibited amplified spontaneous emission and optical gain around 960 nm under optical pulse pumping. A good optical gain

  8. LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Study of relaxation times of polymethine dyes used for passive mode locking of solid-state lasers emitting between 750 and 850 nm

    NASA Astrophysics Data System (ADS)

    Grigonis, R.; Derevyanko, Nadezhda A.; Ishchenko, Aleksandr A.; Sirutkaitis, V. A.

    2001-11-01

    The relaxation times ? of the bleached states of polymethine dyes absorbing light in the 750 — 850-nm are determined by the direct pump — probe method. The effect of the dye structure and the solvent type on the relaxation time is discussed. The role of different intra- and intermolecular interactions in the relaxation of excited electronic states of the dyes is analysed. Polymethine dyes are found (with ?=11 — 75 ps) that are promising for passive mode locking in Cr3+:LiCaAlF6, Cr3+:KZnF3, and Cr3+:LiSrAlF6 crystal lasers.

  9. Self-healing organic-dye-based random lasers.

    PubMed

    Anderson, Benjamin R; Gunawidjaja, Ray; Eilers, Hergen

    2015-02-15

    One of the primary difficulties in the implementation of organic-dye-based random lasers is the tendency of organic dyes to irreversibly photodecay. In this Letter, we report the observation of "reversible" photodegradation in a Rhodamine 6G and ZrO2 nanoparticle-doped polyurethane random laser. We find that during degradation, the emission broadens, redshifts, and decreases in intensity. After degradation, the system is observed to self-heal leading to the emission returning to its pristine intensity, giving a recovery efficiency of 100%. While the peak intensity fully recovers, the process is not strictly "reversible", as the emission after recovery is still found to be broadened and redshifted. The combination of the peak emission fully recovering and the broadening of the emission leads to a remarkable result: the random laser cycled through degradation, and recovery has a greater integrated emission intensity than the pristine system. PMID:25680154

  10. Self-healing organic-dye-based random lasers

    NASA Astrophysics Data System (ADS)

    Anderson, Benjamin R.; Gunawidjaja, Ray; Eilers, Hergen

    2015-02-01

    One of the primary difficulties in the implementation of organic-dye-based random lasers is the tendency of organic dyes to irreversibly photodecay. In this letter we report the observation of "reversible" photodegradation in a Rhodamine 6G and ZrO$_2$ nanoparticle doped polyurethane random laser. We find that during degradation the emission broadens, redshifts, and decreases in intensity. After degradation the system is observed to self-heal leading to the emission returning to its pristine intensity, giving a recovery efficiency of 100%. While the peak intensity fully recovers, the process is not strictly "reversible" as the emission after recovery is still found to be broadened and redshifted. The combination of the peak emission fully recovering and the broadening of the emission leads to a remarkable result: the random laser cycled through degradation and recovery has a greater integrated emission intensity than the pristine system.

  11. Dye-sensitized solar cells using laser processing techniques A. Piqu, a

    E-print Network

    Arnold, Craig B.

    Dye-sensitized solar cells using laser processing techniques H. Kim,a A. Piqué, a G. P. Kushto,a R in dye-sensitized solar cells. LDW enables the fabrication of conformal structures containing metals that is ideally suited for dye-sensitized solar cells. In this experiment, a pulsed UV laser (355nm) is used

  12. Application of the optoacoustic effect in optically pumped submillimeter lasers

    Microsoft Academic Search

    S. T. Shanahan; N. R. Heckenberg

    1984-01-01

    The dependence of the optoacoustic signal generated in an optically pumped submillimetre laser system on gas pressure and modulation frequency has been studied experimentally and the results accounted for theoretically. With care an extracavity optoacoustic cell containing the laser gas diluted with air can be used to stablize the pump laser frequency to maximum absorption but this does not always

  13. Application of the optoacoustic effect in optically pumped submillimeter lasers

    Microsoft Academic Search

    S. T. Shanahan; N. R. Heckenberg

    1984-01-01

    An experimental investigation has been conducted on the dependence of the optoacoustic signal generated in an optically pumped sub-mm laser system on gas pressure and modulation frequency. A theoretical account is given for the results obtained. While an extracavity optoacoustic cell that contains the laser gas (diluted with air) can be used to stabilize the pump laser frequency to maximum

  14. 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.

  15. Thermally induced stresses in end-pumped laser geometries

    Microsoft Academic Search

    J. C. Nieuwoudt; Scott A. Strobel

    1987-01-01

    Thermal stress calculations for an isotropic medium are presented. The calculations simulate a continuous wave laser beam pumping a laser crystal. Two different crystal shapes, a rod and a rectangular slab, are shown to give significantly different stress distributions. The calculation is based on an experiment where an argon laser was used to pump a neodymium: phosphate glass sample and

  16. Diode-pumped 10 W continuous wave cesium laser

    Microsoft Academic Search

    Boris Zhdanov; R. J. Knize

    2007-01-01

    An efficient cesium vapor laser pumped with a continuous wave laser diode array has been demonstrated. The linewidth of the pump source was narrowed using the external cavity to match it to the cesium absorption line. The output power of the continuous wave cesium laser was 10 W, which exceeds previous results by more than a factor of 10, and

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

    Microsoft Academic Search

    Ralph H. Page; Raymond J. Beach; V. Keith Kanz; William F. Krupke

    2006-01-01

    We report what we believe to be the first demonstration of a multimode-diode-pumped gas laser: Rb vapor operating on the 795 nm D1 resonance transition. Peak output of ˜1W 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)

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

    Microsoft Academic Search

    R H Page; R J Beach; V K Kanz

    2005-01-01

    We report the first demonstration of a multimode-diode-pumped gas laser--Rb vapor operating on the 795 nm resonance transition. Peak output of â1 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.

  19. Tunable ultraviolet laser source based on solid-state dye laser technology and CsLiB(6)O(10) harmonic generation.

    PubMed

    Chandra, S; Allik, T H; Hutchinson, J A; Fox, J; Swim, C

    1997-02-15

    Tunable UV radiation centered at 289nm was obtained from a 532-nm Nd:YAG pumped high-brightness solid-state dye laser, frequency doubled in CsLiB(6)O(10). Frequency doubling to 284-294 nm was demonstrated from a singly doped, rotating pyrromethene dye plastic disk with damage threshold >3 J/cm(2) . UV energies up to 44 mJ at 10 Hz were obtained with a 15% absolute conversion efficiency from 532 nm. PMID:18183152

  20. Distributed feedback dye laser holographically induced in improved organic-inorganic photocurable nanocomposites

    NASA Astrophysics Data System (ADS)

    Sakhno, O. V.; Stumpe, J.; Smirnova, T. N.

    2011-06-01

    Distributed feedback (DFB) lasing in permanent volume transmission gratings formed in a laser dye-doped organic-inorganic nanocomposite has been investigated. DFB laser cavities were fabricated using one-step two-beam holographic exposure of Pyrromethene 567 (PM567) doped photopolymerizable acrylate monomers containing inorganic (LaPO4) nanoparticles. Compared to the formulation previously utilized, the material composition presented provides longer lifetime of the laser. Spectral and polarization properties, input-output and stability characteristics of the laser output have been investigated by varying the material composition and the patterning parameters. DFB lasing emission of the second and the third diffraction orders has been demonstrated. The spectral linewidth of ˜0.08 nm has been observed at a pump energy threshold of about 0.2 ?J/pulse for the second-order DFB lasing when pumped with 532 nm 500 ps laser pulses. Spectral tuning of the lasing output over ˜56 and ˜7 nm was obtained by varying the grating period and the content of inorganic nanoparticles in the polymer matrix, respectively.

  1. Diode-pumped 10 W continuous wave cesium laser.

    PubMed

    Zhdanov, Boris; Knize, R J

    2007-08-01

    An efficient cesium vapor laser pumped with a continuous wave laser diode array has been demonstrated. The linewidth of the pump source was narrowed using the external cavity to match it to the cesium absorption line. The output power of the continuous wave cesium laser was 10 W, which exceeds previous results by more than a factor of 10, and the slope efficiency was 68%. The overall optical efficiency was 62%, which is a factor of 6 higher than previous pulsed laser results for alkali lasers with diode laser array pumping. PMID:17671572

  2. Generation of blue light by intracavity frequency mixing of the laser and pump radiation of a miniature neodymium:yttrium aluminum garnet laser

    NASA Astrophysics Data System (ADS)

    Risk, W. P.; Baumert, J.-C.; Bjorklund, G. C.; Schellenberg, F. M.; Lenth, W.

    1988-01-01

    Potassium titanyl phosphate (KTiOPO4,KTP) has been used to generate blue 459-nm radiation by intracavity sum frequency mixing of the circulating 1064-nm laser radiation of a miniature neodymium:yttrium aluminum garnet laser and the 809-nm radiation used as the pump source. A blue output power of approximately 1 mW cw was obtained using 275 mW of pump power from an infrared dye laser. Gain-switched operation leading to high 459-nm peak powers was demonstrated. Direct rapid modulation of the blue radiation was achieved by modulating the pump. In preliminary experiments a high-power laser diode was used as the pump source for the generation of blue radiation.

  3. Femtosecond laser direct writing of single mode polymer micro ring laser with high stability and low pumping threshold.

    PubMed

    Parsanasab, Gholam-Mohammad; Moshkani, Mojtaba; Gharavi, Alireza

    2015-04-01

    We have demonstrated an optically pumped polymer microring laser fabricated by two photon polymerization (TPP) of SU-8. The gain medium is an organic dye (Rhodamine B) doped in SU-8, and the laser cavity is a double coupled microring structure. Single mode lasing was obtained from the two coupled rings each with 30 µm and 29 µm radii using Vernier effect. Low laser threshold of 0.4 µJ/mm2 is achieved using 1 µm wide polymer waveguides and the quality factor is greater than 104 at 612.4 nm wavelength. The lasing remained stable with pump energies from threshold to energies as high as 125 times the threshold. PMID:25968669

  4. Photophysical characterization of pyrromethene 597 laser dye in cross-linked silicon-containing organic copolymers

    NASA Astrophysics Data System (ADS)

    Tyagi, A.; del Agua, D.; Penzkofer, A.; García, O.; Sastre, R.; Costela, A.; García-Moreno, I.

    2007-12-01

    Samples of the dipyrromethene-BF 2 dye PM597 incorporated in copolymers of 3-trimethoxysilylpropyl 2-methylprop-2-enoate (TMSPMA, number of polymerizable CC double bonds: ? = 1) with 2-(2-methylprop-2-enoyloxy)ethyl 2-methylprop-2-enoate (EGDMA, ? = 2), [2-(hydroxymethyl)-3-prop-2-(prop-2-enoyloxymethyl)propyl] prop-2-enoate (PETA, ? = 3), and [3-prop-2-enoyloxy-2,2-bis(prop-2-2-enoyloxymethyl)propyl]prop-2-enoate (PETRA, ? = 4) are characterized. The fluorescence quantum distributions, fluorescence quantum yields, degrees of fluorescence polarization, and fluorescence lifetimes are measured. The radiative lifetimes are calculated from fluorescence lifetime and quantum yield. Absorption coefficient spectra are determined from transmission measurements. Absolute absorption cross-section spectra and dye concentrations are obtained by calibration to the radiative lifetimes and to saturable absorptions. Excited-state absorption cross-sections at 527 nm are determined by saturable absorption measurements. The photo-degradation is studied under cw laser excitation conditions and quantum yields of photo-degradation are extracted. The excited-state absorption cross-sections were found to be rather small, and the photo-stability turned out to be high (up to 3 million excitation cycles before degradation) making this class of dipyrromethene dye-doped polymers attractive active laser media. Structural and thermo-mechanical properties of the materials have been determined by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetry, densitometry, and refractometry. They improve with increasing inter-crossing (copolymerization of TMSPMA with PETA and PETRA). The laser properties of the PM597 doped copolymers were evaluated by transverse pumping with 6 ns laser pulses at 532 nm. The best laser materials resulted to be the 7:3 and 9:1 TMSPMA-monomer copolymers.

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

    Microsoft Academic Search

    Clifford V. Sulham

    2010-01-01

    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

  6. 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.

  7. Energy transfer mechanism between laser dyes doped in ORMOSILs

    NASA Astrophysics Data System (ADS)

    Yang, Yu; Qian, Guodong; Su, Deliang; Wang, Zhiyu; Wang, Minquan

    2005-02-01

    Laser dyes perylene orange (p-orange) or perylene red (p-red) or pyrromethene 567 (p567) were co-doped with coumarin 440 (C440) or coumarin 500 (C500) into MTES- and VTES-derived organically modified silicates (ORMOSILs) by sol-gel process. Energy transfer from both C440 and C500, energy donors, to p-red, p-orange and p567, acceptor, respectively, has been observed and studied by steady-state emission measurement. The effect of donor concentration on energy transfer and its mechanism were studied. The potential application as an energy transfer dye laser (ETDL) was also discussed. At least 1-fold increase in the slope efficiency of p-red and 3-fold increase in the photostability of p567 was observed in such ETDLs.

  8. Dye laser amplifier including an improved window configuration for its dye beam

    DOEpatents

    O'Neil, Richard W. (Pleasanton, CA); Davin, James M. (Livermore, CA)

    1992-01-01

    A dye laser amplifier in which a continuously replenished supply of dye is excited with a first light beam in order to amplify the intensity of a second different light beam passing therethrough is disclosed herein. This amplifier includes a cell though which a continuous stream of the dye is caused to pass, and means for directing the first beam into the cell while the second beam is directed into and through the same cell. There is also disclosed herein a specific improvement to this amplifier which resides in the use of a pair of particularly configured windows through which the second beam passes along fixed paths as the second beam enters and exits the dye cell. Each of these windows has a relatively thick main section which is substantially larger in dimensions transverse to its beam path than the cross section of the second beam itself, whereby to add structural integrity to the overall window. At the same time, the latter includes a second section which is disposed entirely within the confines of the main section and through which the second beam is intended to pass in its entirety. This second section is made substantially thinner than the main section in order to reduce optical distortion as the second beam passes therethrough.

  9. Dye laser amplifier including an improved window configuration for its dye beam

    DOEpatents

    O'Neil, R.W.; Davin, J.M.

    1992-12-01

    A dye laser amplifier in which a continuously replenished supply of dye is excited with a first light beam in order to amplify the intensity of a second different light beam passing therethrough is disclosed herein. This amplifier includes a cell though which a continuous stream of the dye is caused to pass, and means for directing the first beam into the cell while the second beam is directed into and through the same cell. There is also disclosed herein a specific improvement to this amplifier which resides in the use of a pair of particularly configured windows through which the second beam passes along fixed paths as the second beam enters and exits the dye cell. Each of these windows has a relatively thick main section which is substantially larger in dimensions transverse to its beam path than the cross section of the second beam itself, whereby to add structural integrity to the overall window. At the same time, the latter includes a second section which is disposed entirely within the confines of the main section and through which the second beam is intended to pass in its entirety. This second section is made substantially thinner than the main section in order to reduce optical distortion as the second beam passes therethrough. 4 figs.

  10. Cascaded Energy Transfer for Efficient Broad-Band Pumping of High Quality, Micro Lasers

    SciTech Connect

    Rotschild, Carmel; Tomes, M.; Mendoza, H.; Andrew, T. L.; Swager, Timothy M.; Carmon, T.; Baldo, Marc

    2011-01-01

    Micro-ring lasers that exhibit a quality factor (Q) larger than 5.2 × 10{sup 6} with a direct-illumination, non-resonant pump are demonstrated. The micro-rings are coated with three organic dyes forming a cascaded energy-transfer, which reduces material-losses by a factor larger than 10{sup 4}, transforming incoherent light to coherent light with high quantum-efficiency. The operating principle is general and can enable fully integrated on-chip, high-Q micro-lasers.

  11. Efficient laser action from two cw laser-pumped pyrromethene-BF(2) complexes.

    PubMed

    Guggenheimer, S C; Boyer, J H; Thangaraj, K; Shah, M; Soong, M L; Paviopoulos, T G

    1993-07-20

    Two new pyrromethene-BF(2) dyes, P-556 and P-567, are tested for cw laser operation. P-556 demonstrates a significant advance in the 530-620-nm region over commercially currently available dyes, where the best cw dyes in any range have peak efficiencies of the order of 35% and dyes in this range typically have less then 25%. The P-556 has a cw efficiency of 45% at the peak. PMID:20830030

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

    SciTech Connect

    Miller, Wooddy S.; Sulham, Clifford V.; Holtgrave, Jeremy C.; Perram, Glen P. [Department of Engineering Physics, Air Force Institute of Technology, 2950 Hobson Way, Wright-Patterson Air Force Base, Ohio 45433-7765 (United States)

    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.

  13. Nuclear pumped laser research at the Jet Propulsion Laboratory

    NASA Technical Reports Server (NTRS)

    Russell, G. R.

    1979-01-01

    Using a partially nuclear excited xenon flashlamp to pump an iodine laser, laser pulse shapes were analyzed with and without nuclear flashlamp augmentation. The pulse shapes indicate that the deposition of nuclear energy is equally as effective as electrical energy deposition in producing laser pulse energy output. The amplification of the E-beam pumped CF3I was measured at pressures of several atmospheres. Preliminary data shows that, for a part of the iodine laser pulse, amplification of almost a factor of two is measured. This measurement indicates that the gain in an E-beam pumped CF3I is an order of magnitude greater than in the coaxial laser tube.

  14. Absolute tracer dye concentration using airborne laser-induced water Raman backscatter

    NASA Technical Reports Server (NTRS)

    Hoge, F. E.; Swift, R. N.

    1981-01-01

    The use of simultaneous airborne-laser-induced dye fluorescence and water Raman backscatter to measure the absolute concentration of an ocean-dispersed tracer dye is discussed. Theoretical considerations of the calculation of dye concentration by the numerical comparison of airborne laser-induced fluorescence spectra with laboratory spectra for known dye concentrations using the 3400/cm OH-stretch water Raman scatter as a calibration signal are presented which show that minimum errors are obtained and no data concerning water mass transmission properties are required when the laser wavelength is chosen to yield a Raman signal near the dye emission band. Results of field experiments conducted with an airborne conical scan lidar over a site in New York Bight into which rhodamine dye had been injected in a study of oil spill dispersion are then indicated which resulted in a contour map of dye concentrations, with a minimum detectable dye concentration of approximately 2 ppb by weight.

  15. Identification Of Natural Dyes On Archaeological Textile Objects Using Laser Induced Fluorescent Technique

    NASA Astrophysics Data System (ADS)

    Abdel-Kareem, O.; Eltokhy, A.; Harith, M. A.

    2011-09-01

    This study aims to evaluate the use of Laser Fluorescent as a non-destructive technique for identification of natural dyes on archaeological textile objects. In this study wool textile samples were dyed with 10 natural dyes such as cochineal, cutch, henna, indigo, Lac, madder, safflower, saffron, sumac and turmeric. These dyes common present on archaeological textile objects to be used as standard dyed textile samples. These selected natural dyes will be used as known references that can be used a guide to identify unknown archaeological dyes. The dyed textile samples were investigated with laser radiation in different wavelengths to detect the best wavelengths for identification each dye. This study confirms that Laser Florescent is very useful and a rapid technique can be used as a non-destructive technique for identification of natural dyes on archaeological textile objects. The results obtained with this study can be a guide for all conservators in identification of natural organic dyes on archaeological textile objects.

  16. Quantum theory of a squeezed-pump laser

    SciTech Connect

    Marte, M.A.M.; Walls, D.F.

    1988-02-15

    We analyze a model of a laser pumped by an incoherent source in a squeezed vacuum state. The squeezed pump introduces an anisotropy of phase in the laser output. Above threshold two stable solutions are found, with phases corresponding to the directions along which the noise of the bath is quenched. These solutions are illustrated by the potential function of the laser field. An analysis of fluctuations shows that the laser field has reduced phase fluctuations but not below the quantum limit.

  17. Application of the optoacoustic effect in optically pumped submillimeter lasers

    SciTech Connect

    Shanahan, S.T.; Heckenberg, N.R.

    1984-03-01

    An experimental investigation has been conducted on the dependence of the optoacoustic signal generated in an optically pumped sub-mm laser system on gas pressure and modulation frequency. A theoretical account is given for the results obtained. While an extracavity optoacoustic cell that contains the laser gas (diluted with air) can be used to stabilize the pump laser frequency to maximum absorption, it is noted that laser output optimization does not always result. 10 references.

  18. Single mode coupled optofluidic ring resonator dye lasers Xiang Wu,1,2

    E-print Network

    Fan, Xudong "Sherman"

    Single mode coupled optofluidic ring resonator dye lasers Xiang Wu,1,2 Yuze Sun,1 Jonathan D. Suter The authors demonstrate the single mode dye laser from a coupled optofluidic ring resonator that consists gratings,7­10 and ring resonators. While tunable and single mode operation lasers have been realized using

  19. The role of the molecular dynamics in the local intensity instabilities of large aperture dye lasers

    E-print Network

    Rey Juan Carlos, Universidad

    lasers I. Leyvaa) and J. M. Guerra Departamento de O´ ptica, Facultad de Ciencias Fi´sicas Universidad fluctuations of large aperture dye lasers, and find dependencies on solvent viscosity and active molecular size dye lasers are used in a great deal of practical applications, from isotope enrichment to photody

  20. The role of the solvent viscosity on the spatiotemporal instabilities of large aperture dye lasers

    E-print Network

    Rey Juan Carlos, Universidad

    The role of the solvent viscosity on the spatiotemporal instabilities of large aperture dye lasers for publication 27 May 1998 Local intensity fluctuations in a large aperture dye laser have been measured behavior as the molecular polarization orientation driven by the laser field. © 1998 American Institute

  1. Development of excellent long-wavelength BODIPY laser dyes with a strategy that combines extending ?-conjugation and tuning ICT effect.

    PubMed

    Zhang, Dakui; Martín, Virginia; García-Moreno, Inmaculada; Costela, Angel; Pérez-Ojeda, M Eugenia; Xiao, Yi

    2011-07-28

    By comparison and combination of two strategies, extending ?-conjugation and tuning Intramolecular Charge Transfer (ICT) effect, new long-wavelength BODIPY dyes have been efficiently synthesized. The new chromophores exhibit good optical properties: high fluorescence quantum yields, exceptionally large molar extinction coefficients, narrow red-emission bands, and relatively large Stokes shifts etc., in polar or apolar solvents. Besides, the new dyes, under transversal pumping at 532 nm, exhibit highly efficient and stable laser emission tunable from the green to NIR spectral region (570-725 nm). Moreover, one of these new BODIPY derivatives shows cell membrane permeability and bright intracellular red fluorescence. These advantageous characteristics assure the potential of these dyes for biophotonic applications. PMID:21691659

  2. High-power optically pumped semiconductor laser apllications

    NASA Astrophysics Data System (ADS)

    Morioka, S. Brandon

    2011-03-01

    OPS lasers have found applications in various industrial and scientific laser applications due to their power scaling capability, their wide range of emission wavelengths, physical size and their superior reliability. This paper provides an overview of commercially available OPS lasers and the applications in which they are used including biotechnology, medical, holography, Titanium-Sapphire laser pumping, non-lethal defense, forensics, and entertainment.

  3. Diode pumped alkali vapor lasers for high power applications

    Microsoft Academic Search

    J. Zweiback; B. Krupke; A. Komashko

    2008-01-01

    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

  4. 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 ?m range are studied. Lasing is obtained at ? = 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.

  5. High-efficiency diode-pumped rubidium laser: experimental results

    Microsoft Academic Search

    Ty A. Perschbacher; David A. Hostutler; T. M. Shay

    2007-01-01

    A diode-pumped rubidium laser with an optical slope efficiency of 69% has been constructed. This study utilized a narrow-line diode laser pump source for the experiments. The trade space study included optimization of various parameters such as lasing cell composition, temperature, and output coupler reflectivities. The results of the experimental study are given.

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

    DOEpatents

    Rockwood, Stephen D. (Los Alamos, NM)

    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.

  7. Combined cw single-frequency ring dye/Ti:sapphire laser

    SciTech Connect

    Kobtsev, Sergey M; Baraulya, Vladimir I [Novosibirsk State University, Novosibirsk (Russian Federation); Lunin, Vladimir M [Tekhnoscan Joint-Stock Company, Novosibirsk (Russian Federation)

    2006-12-31

    A new combined cw single-frequency dye/Ti:sapphire laser with a ring resonator located in the horizontal plane and improved radiation frequency stability is developed. The short-term radiation linewidth does not exceed 10 kHz for the Ti:sapphire laser and is smaller than 100 kHz for the dye laser. The drift velocity of the emission line does not exceed 25 MHz h{sup -1}. The scheme and design of the developed laser are presented which allow convenient switching of the laser between its solid-state and dye configurations. (lasers)

  8. Congeners of Pyrromethene-567 Dye: Perspectives from Synthesis, Photophysics, Photostability, Laser, and TD-DFT Theory.

    PubMed

    Thorat, Kishor G; Kamble, Priyadarshani; Mallah, Ramnath; Ray, Alok K; Sekar, Nagaiyan

    2015-06-19

    In an attempt to develop photostable and efficient BODIPY (PM) dyes for use in liquid dye lasers, three new congeners of widely used laser dye, PM567, were synthesized and their photophysical properties in various organic solvents, laser performances, and photostabilities in a selected solvent, 1,4-dioxane, have been investigated using a frequency doubled Q-switched (10 Hz) Nd:YAG laser at 532 nm. The results of photostability study in nonpolar 1,4-dioxane revealed the remarkable enhancement in stability of the novel dyes compared to that of PM567 as well as improved laser performances. Cyclic voltammetry study strongly supports the observed enhancement in photostability of the novel dyes compared to that of PM567. The observed properties of the novel dyes in relation to those of PM567 have been rationalized by extensive use of DFT and TD-DFT using the B3LYP/6-31G(d) method of theory. PMID:26001098

  9. Laser velocimetry with fluorescent dye-doped polystyrene microspheres.

    PubMed

    Lowe, K Todd; Maisto, Pietro; Byun, Gwibo; Simpson, Roger L; Verkamp, Max; Danehy, Paul M; Tiemsin, Pacita I; Wohl, Christopher J

    2013-04-15

    Simultaneous Mie scattering and laser-induced fluorescence (LIF) signals are obtained from individual polystyrene latex microspheres dispersed in an air flow. Microspheres less than 1 ?m mean diameter were doped with two organic fluorescent dyes, Rhodamine B (RhB) and dichlorofluorescein (DCF), intended either to provide improved particle-based flow velocimetry in the vicinity of surfaces or to provide scalar flow information (e.g., marking one of two fluid streams). Both dyes exhibit measureable fluorescence signals that are on the order of 10(-3) to 10(-4) times weaker than the simultaneously measured Mie signals. It is determined that at the conditions measured, 95.5% of RhB LIF signals and 32.2% of DCF signals provide valid laser-Doppler velocimetry measurements compared with the Mie scattering validation rate with 6.5 W of 532 nm excitation, while RhB excited with 1.0 W incident laser power still exhibits 95.4% valid velocimetry signals from the LIF channel. The results suggest that the method is applicable to wind tunnel measurements near walls where laser flare can be a limiting factor and monodisperse particles are essential. PMID:23595429

  10. Exciplex pumped alkali laser (XPAL) modeling and theory

    Microsoft Academic Search

    Andrew D. Palla; Joseph T. Verdeyen; David L. Carroll

    2010-01-01

    The exciplex pumped alkali laser (XPAL) system has been demonstrated in mixtures of Cs vapor, Ar, with and without ethane, by pumping Cs-Ar atomic collision pairs and subsequent dissociation of diatomic, electronically-excited CsAr molecules (exciplexes or excimers). The blue satellites of the alkali D2 lines provide an advantageous pathway for optically pumping atomic alkali lasers on the principal series (resonance)

  11. 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)

  12. Eumelanin Dye-sensitized Solar Cell Grown with Matrix-assisted Pulsed Laser

    E-print Network

    Eumelanin Dye-sensitized Solar Cell Grown with Matrix-assisted Pulsed Laser Evaporation~4 DHICA DHICA #12; III Abstract At present the majority dye-sensitized solar cell research all, and besides provides and does not have other uses for the dye-sensitized solar cell use. In order to improve

  13. Identification Of Natural Dyes On Archaeological Textile Objects Using Laser Induced Fluorescent Technique

    Microsoft Academic Search

    O. Abdel-Kareem; A. Eltokhy; M. A. Harith

    2011-01-01

    This study aims to evaluate the use of Laser Fluorescent as a non-destructive technique for identification of natural dyes on archaeological textile objects. In this study wool textile samples were dyed with 10 natural dyes such as cochineal, cutch, henna, indigo, Lac, madder, safflower, saffron, sumac and turmeric. These dyes common present on archaeological textile objects to be used as

  14. Preparation of certain m-aminophenols and the use thereof for preparation of laser dyes

    DOEpatents

    Hammond, P.R.

    1983-12-29

    Methods are provided for making certain m-aminophenols using a sulfonation/alkali fusion procedure. The aminophenols are key intermediates in the synthesis of dyes, particularly efficient, stable dyes for laser application. Preparations of some rhodamine and phenoxazone dyes from the m-aminophenols are described.

  15. Interpretation of the Raman absorptionn lines within the stimulated fluorescence spectrum of some laser dyes

    Microsoft Academic Search

    M. Pfeiffer; A. Lau; H.-J. Weigmann; K. Lenz

    1972-01-01

    The emission spectrum of some laser dyes shows the appearance of Raman abssorption lines within the generation continuum. The absorption line can be interpreted as a gap in the fluorescence profile of the dye molecule. Here we show theoretically with a simple model for the dye molecule, that such gap really exists, lying just at the Raman frequency. The characteristics

  16. Ultraviolet lasers. Citations from the International Aerospace Abstracts data base

    NASA Technical Reports Server (NTRS)

    Mauk, S. C.

    1980-01-01

    Reports cited from the international literature describe various aspects of ultraviolet lasers including laser output, far ultraviolet radiation, electron pumping, optical pumping, and laser materials. Gas lasers, pulsed lasers, dye lasers, CO2 lasers, xenon fluoride lasers, and transversely excited atmospheric (TEA) lasers are considered. This updated bibliography contains 283 citations, 66 of which are new additions to the previous edition.

  17. 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 [M.F. Stel'makh Polyus Research and Development Institute, Moscow (Russian Federation); Pleshanov, S A [Federal State Unitary Enterprise 'Istok Research and Production Association', Fryazino, Moscow region (Russian Federation)

    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)

  18. Pumping of atomic alkali lasers by photoexcitation of a resonance line blue satellite and alkali-rare gas excimer dissociation

    Microsoft Academic Search

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

    2009-01-01

    Photoassociation of alkali-rare gas atomic collision pairs provides an alternative approach to optically pumping atomic alkali lasers. Lasing on the 6 2P1\\/2?6 2S1\\/2(D1) transition of Cs has been observed when the blue satellite of the 6 2P3\\/2?6 2S1\\/2(D2) transition, peaking at ?837 nm for mixtures of Cs vapor, Ar, and ethane, is pumped by a pulsed dye laser. For 50%

  19. Flashlamp-pumped Ti:Sapphire laser: Influence of the rod figure of merit and Ti3+ concentration

    NASA Astrophysics Data System (ADS)

    Boquillon, J. P.; Musset, O.

    1994-09-01

    A flashlamp-pumped Ti:Sapphire laser is tested with rods of various Figures of Merit (FOM from 100 to 800) and Ti3+ concentrations (0.1 and 0.15% by weight) and we measured the laser energy dependence as a function of these parameters. Output energies above 2 J are obtained without dye converter, leading to a 1.8% overall efficiency and a 2.2% slope efficiency. The effects of pump pulse duration by variation of the discharge capacitance are also monitored.

  20. Highly photostable solid-state dye lasers based on mixed pyrromethene 567 and coumarin 500

    NASA Astrophysics Data System (ADS)

    Chen, D. Y.; Jiang, Y. G.; Fan, R. W.; Jia, E. B.; Xia, Y. Q.; Yao, Y.

    2009-09-01

    Solid-state dye samples based on polymethyl methacrylate (PMMA) co-doped with pyrromethene 567 (PM567) and coumarin 500 (C500) were prepared. The effects of C500 concentration on the performances of the solid state dye mediums, including spectra property, slope efficiency and photostability were studied. The highest slope efficiency 64.25% was obtained in the sample (PM567: C500 = 2: 8). Pumping the samples at a rate of 5Hz with a pulse energy as high as 100 mJ (the fluence was 0.26 J/cm2), the output energy dropped to half of its initial value after approximate 116130 pulses and the normalized photostability reached 75.48 GJ/mol in the sample (PM567: C500 = 2: 1). Our results have shown that it is possible to obtain a high-efficiency with a long-lifetime for a solid-state dye laser co-doped with PM567 and C500.

  1. 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.

  2. Stimulated Raman scattering of laser dye mixtures dissolved in multiple scattering media

    NASA Astrophysics Data System (ADS)

    Yashchuk, V. P.; Komyshan, A. O.; Tikhonov, E. A.; Olkhovyk, L. A.

    2014-10-01

    Stimulated Raman scattering (SRS) of a mixture of rhodamine 6G and pyrromethene 605 laser dyes in vesicular films is studied. It is shown that a peculiar interaction of dyes occurs under conditions of multiple scattering of light from vesicles. This interaction manifests itself as SRS excitation of one of the dyes by random lasing of the other dye, provided that the random lasing spectrum overlaps the Stokes lines of the first dye. In addition, there is energy transfer between molecules of these dyes if their luminescence and absorption spectra overlap. The results obtained confirm that the mechanism of SRS from laser dyes in multiple scattering media is similar to that in coherent-active Raman spectroscopy. These results extend the possibility of determining the vibrational spectrum of dye molecules from their secondary radiation in these media.

  3. A pulsed, optically-pumped rubidium laser at high pump intensity

    Microsoft Academic Search

    Clifford V. Sulham; Glen P. Perram; Michael P. Wilkinson; David A. Hostutler

    2010-01-01

    A rubidium laser operating at 795 nm is optically pumped by a pulsed titanium sapphire laser to investigate the dynamics of Diode Pumped Alkali Lasers (DPALs). Linear scaling of output intensity for longitudinal excitation at intensities of 1.3-43 kW\\/cm2 and as much as 32 times threshold is observed. The slope efficiency depends directly on the number of absorbed photons for

  4. A pulsed, optically-pumped rubidium laser at high pump intensity

    Microsoft Academic Search

    Clifford V. Sulham; Glen P. Perram; Michael P. Wilkinson; David A. Hostutler

    2010-01-01

    A rubidium laser operating at 795nm is optically pumped by a pulsed titanium sapphire laser to investigate the dynamics of Diode Pumped Alkali Lasers (DPALs). Linear scaling of output intensity for longitudinal excitation at intensities of 1.3–43kW\\/cm2 and as much as 32 times threshold is observed. The slope efficiency depends directly on the number of absorbed photons for alkali concentrations

  5. Dynamics of coherently pumped lasers with linearly polarized pump and generated fields

    Microsoft Academic Search

    R. Corbalán; R. Vilaseca; M. Arjona; J. Pujol; E. Roldán; G. J. de Valcárcel

    1993-01-01

    The influence of light polarization on the dynamics of an optically pumped single-mode laser with a homogeneously broadened four-level medium is theoretically investigated in detail. Pump and laser fields with either parallel or crossed linear polarizations are considered, as are typical in far-infrared-laser experiments. Numerical simulations reveal dramatically different dynamic behaviors for these two polarization configurations. The analysis of the

  6. 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.

  7. High power CW iodine laser pumped by solar simulator

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Lee, Min H.; Weaver, Willard R.

    1987-01-01

    An iodine photodissociation laser was pumped by a long Ar arc as the solar simulator to produce a 10-W CW output. Continuous lasing for 1 h was achieved with a flow of the laser material n-C3F7I. The 10-W CW output is the highest produced to date and establishes the feasibility of developing a solar-pumped laser for space power transmission.

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

    Microsoft Academic Search

    Amarin Ratanavis

    2010-01-01

    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.

  9. Lorenz-like dynamics in Doppler broadened coherently pumped lasers

    Microsoft Academic Search

    R. Corbalán; F. Laguarta; J. Pujol; R. Vilaseca

    1989-01-01

    We report the theoretical interpretation of Lorenz-like behavior recently observed for the first time in a laser by Weiss and Brock [Phys. Rev. Lett. 57 (1986) 2804]. By means of a three-level laser model it is shown that in an optically-pumped far-infrared laser, coherent pumping effects are partially smeared out by Doppler broadening and as a result Lorenz-like dynamics may

  10. 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.

  11. 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.

  12. Low threshold solar-pumped iodine laser

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J.

    1986-01-01

    Solar-pumped lasing of i-C3F7I and n-C4F9I at lower solar concentrations (170 solar constants) and longer gain lengths than previous solar lasers is demonstrated, with potential application to the lasing needs of space. Two xenon arc solar simulators provide an AM0 spectrum over the 60-cm gain length, and output pulse energies of 70 mJ and an average power of 550 mW are achieved. Low pressure lasing times of 600 ms are reached, and the observed 0.074 percent slope efficiency could approach the 0.2 percent maximum theoretical efficiency. Due to less quenching of I(asterisk), n-C4F9I is found to be a superior lasant to i-C3F7I.

  13. Theoretical studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, W. L.

    1981-01-01

    Estimates of the absorption and emission characteristics of molecules required to develop materials for solar-pumped lasers are addressed. These characteristics are described in terms of the Franck Condon factors, which are calculated from the molecular wave functions. Wave functions for vibrational levels in the lower and upper electronic states of I2 and NSe are calculated numerically and methods of checking errors discussed. Errors arise when the vibrational quantum numbers are high; but, using a calculated rather than measured value of the dissociation energy, wave functions up to the fiftieth vibrational level are obtained. A numerical method of evaluating the wave functions is given, which should be more accurate in the region of electronic transitions during absorption. Franck Condon factors, plotted versus the wavelength of the absorbed photons, are shown, and a check on the Franck Condon factors is made using the vibrational sum rule.

  14. 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.

  15. Tunable narrow linewidth laser output from PM567 doped nematic liquid crystal under holographic pumping

    NASA Astrophysics Data System (ADS)

    Chen, D. Y.; Fan, Y. K.; Fan, R. W.; Xia, Y. Q.

    2011-12-01

    LC cell injected the mixture of dye pyrromethene 567 (PM567) and nematic liquid crystal (NLC) by capillary action was prepared. Holographic pumping with a Nd:YAG laser (532 nm, 1 Hz, 10 ns) to form gain distributed feedback in the cell, tunable laser output from the cell was investigated. Through changing the intersection angles of the two coherent light beams from 46° to 50°, the tuning range we obtained is about 37 nm (550-587 nm). Additionally, the FWHM of the laser under such experimental setup was less than 0.1 nm even without the resonant cavity, and the threshold of the laser was about 26 ?J, which was very low as we known.

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

    Microsoft Academic Search

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

    1992-01-01

    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

  17. Operating temperature of diode-pumped alkali vapor laser

    Microsoft Academic Search

    Qiang Zhu; Jianhua Yu; Wei Zheng; Hongyan Quan

    2008-01-01

    Diode-pumped alkali vapor laser (DPAL) is a new class of laser, and it is expected to realize high efficiency and high-average-power laser with good beam quality (near-diffraction-limited). DPAL offers CW laser radiation at near-infrared wavelengths and can find a lot of applications in power beaming, drilling oil and gas well and laser material processing. Operating temperature affects not only the

  18. Pulsed dye laser for the treatment of nail psoriasis.

    PubMed

    Yin, Natalie; Choudhary, Sonal; Nouri, Keyvan

    2013-09-01

    Psoriasis can involve the skin, joints, and nails, either alone or in combination. Psoriasis of the nails can involve both the nail bed and nail matrix. The treatment of nail psoriasis largely depends on the severity of symptoms. The pulsed dye laser (PDL) recently has demonstrated efficacy in treating resistant plaque-type psoriasis and has been suggested as an alternative to conventional therapies. We review 4 studies of PDL for nail psoriasis and discuss the findings in relation to treatment recommendations. Ultimately, a standardized regimen for the treatment of nail psoriasis remains elusive. PMID:24153141

  19. DPSS Laser Beam Quality Optimization Through Pump Current Tuning

    SciTech Connect

    Omohundro, Rob; /Newport Spectra-Physics, Santa Clara; Callen, Alice; /SLAC; 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.

  20. Complete electromagnetically induced transparency in sodium atoms excited by a multimode dye laser

    E-print Network

    Complete electromagnetically induced transparency in sodium atoms excited by a multimode dye laser experimentally by means of excitation with a broadband multimode dye laser tuned on the D1 line. One hundred orders of magnitude narrower than the natural width of the corresponding optical transitions. CPT

  1. Pancreatic and biliary calculi: percutaneous treatment with tunable dye laser lithotripsy.

    PubMed

    Feldman, R K; Freeny, P C; Kozarek, R A

    1990-03-01

    Percutaneous tunable dye laser lithotripsy was used in two patients to successfully fragment a 2-cm left hepatic duct calculus and a 5-mm main pancreatic duct calculus. Tunable dye laser lithotripsy may prove to be a more effective alternative to mechanical lithotripsy. PMID:1968280

  2. Tunable optical parametric oscillators pumped by Ti:sapphire lasers.

    PubMed

    Zenzie, H H; Moulton, P F

    1994-07-01

    We report on the application of tunable, pulsed Ti:sapphire lasers as efficient pump sources for optical parametric oscillators. Using a 90-deg phase-matched KTP crystal, we have generated output from 1030 to 1280 nm (signal) and 2180 to 3030 nm (idler) by tuning the pump laser from 700 to 900 nm, with 49 mJ of combined signal and idler output energy at a pump level of 110 mJ. In addition, we have demonstrated degenerate optical parametric oscillator operation with a KNbO(3) crystal over the pump range of 720-818 nm and observed a 44% conversion efficiency. PMID:19844502

  3. Taming Random Lasers through Active Spatial Control of the Pump

    NASA Astrophysics Data System (ADS)

    Bachelard, N.; Andreasen, J.; Gigan, S.; Sebbah, P.

    2012-07-01

    Active control of the spatial pump profile is proposed to exercise control over random laser emission. We demonstrate numerically the selection of any desired lasing mode from the emission spectrum. An iterative optimization method is employed, first in the regime of strong scattering where modes are spatially localized and can be easily selected using local pumping. Remarkably, this method works efficiently even in the weakly scattering regime, where strong spatial overlap of the modes precludes spatial selectivity. A complex optimized pump profile is found, which selects the desired lasing mode at the expense of others, thus demonstrating the potential of pump shaping for robust and controllable single mode operation of a random laser.

  4. Pump pulse-width dependence of grazing-incidence pumped transient collisional soft-x-ray lasers M. Berrill,1

    E-print Network

    Rocca, Jorge J.

    Pump pulse-width dependence of grazing-incidence pumped transient collisional soft-x-ray lasers M 2007 The output energy dependence of high repetition rate grazing incidence pumped Ni-like Mo, Ni-like Ag, and Ne-like Ti transient collisional soft x-ray lasers on the duration of the pump pulse

  5. CW-pumped polarization-maintaining Brillouin fiber ring laser

    E-print Network

    Boyer, Edmond

    CW-pumped polarization-maintaining Brillouin fiber ring laser: I. Self-structuration of Brillouin for a large set of (G, R) parameters, in a polarization-maintaining Brillouin fiber ring laser in the best performed in a polarization- maintaining Brillouin fiber ring laser in good conditions of stability

  6. Diatomic Cesium in a Diode-Pumped Alkali Laser System

    Microsoft Academic Search

    Jamey Christy; Eric Martinez; Tanner Oakes; Jake Smith; Kendrick Walter

    2008-01-01

    Abstract Diode Pumped Alkali Laser (DPAL) systems combine the positive characteristics of chemical and diode lasers. These systems create a laser that is compact and ecient, while working well at high temperatures and high powers. In conjunction with the Air Force Research Laboratory (AFRL), an attempt was made to improve DPAL technology by using a diatomic alkali metal as a

  7. Advances in high-power diode-pumped ultraviolet lasers

    Microsoft Academic Search

    Acle V. Hicks; Charles X. Wang; Gary Y. Wang

    2004-01-01

    In the past five years diode-pumped Q-switched vanadate and YAG lasers with 355 nm and 266 nm output have advanced in power level and reliability and are now qualified in many industrial processes. In this paper we will discuss the design and performance of these lasers with consideration of available power and wavelength of laser diodes, selection of materials for

  8. Experiments and simulations of short-pulse laser-pumped extreme ultraviolet lasers

    Microsoft Academic Search

    G. J. Tallents; Y. Abou-Ali; A. Demir; Q. Dong; M. H. Edwards; P. Mistry; G. J. Pert

    2004-01-01

    Recent experimental work on the development of extreme ultraviolet lasers undertaken using as the pumping source the VULCAN laser at the Rutherford Appleton Laboratory is compared to detailed simulations. It is shown that short duration (?picosecond) pumping can produce X-ray laser pulses of a few picosecond duration and that measurement of the emission from the plasma can give an estimate

  9. Highly efficient and photostable solid-state dye lasers doped with PM567 with the addition of Tinuvin770

    NASA Astrophysics Data System (ADS)

    Fan, R. W.; Jiang, Y. G.; Xia, Y. Q.; Chen, D. Y.

    2011-06-01

    Solid-state dye samples based on polymethyl methacrylate (PMMA) doped with pyrromethene 567 (PM567) with the addition of Tinuvin770 were prepared. The effects of a light stabilizer and concentration on the laser performances of the solid state dye PM567, including spectra properties, slope efficiency and photostability were investigated. The highest slope efficiency 66.6% was obtained in the sample (PM567:Tinuvin770 = 2.0:0.5). The addition of Tinuvin770 resulted in a dramatic enhancement of photo-stability. Pumping the samples at a rate of 5 Hz with a pulse energy as high as 100 mJ (the pump energy density was 0.26 J/cm2), the output energy dropped to half of its initial value after approximate 149500 shots and the normalized photostability reached 97.2 GJ/mol in the sample (PM567:Tinuvin770 = 2:5). All results have shown that a high efficient and photostable solid-state dye laser with the addition of Tinuvin770 can be obtained.

  10. Frequency stabilization of diode-laser-pumped solid state lasers. Final technical report

    Microsoft Academic Search

    Byer

    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

  11. Laser dye spectroscopy of some pyrromethene-BF(2) complexes.

    PubMed

    Paviopoulos, T G; Boyer, J H; Thangaraj, K; Sathyamoorthi, G; Shah, M P; Soong, M L

    1992-11-20

    To improve the laser action properties of the pyrromethene-BF(2) (P-BF(2)) complexes, we studied substitution effects at different positions of the dye molecule on the electronic spectra of several derivatives. Specifically, we used laser photoselection spectroscopy to measure the triplet-triplet (T-T) absorption and polarization spectra as well as the fluorescence and visible absorption singlet-singlet (S-S) spectra of the following compounds: 1,2,3,5,6,7,8-heptamethyl; 8-acetoxymethyl-1,3,5,7-tetramethyl-2,6-diethyl; 1,3,5,7-tetramethyl-8-p-methoxyphenyl; 3,5-dimethyl-1,7-diphenyl; and 1,3,5,7,8-pentamethyl- 2,6-diphenyl P-BF(2) complexes. The 1,3,5,7-tetramethyl P-BF(2) complex itself exhibits weak T-T absorption, which stretches from the green to the near-IR spectral region. This band consists of two overlapping (differently polarized) T-T transitions. Short molecular axis (i.e., 8 and 1,7 positions) substitution causes the positively polarized T-T transition to gain considerably in intensity. Significantly, the negatively, long-axis-polarized T-T transition was unaffected by the long-axis 2,6- position disubstitution. Therefore, only the 2,6-position disubstitution is expected to produce superior new P-BF(2) complex laser dyes. Substitution effects from strongly interacting groups with chromophores on S-S as well as T-T absorption spectra, together with cw laser photoselection spectroscopy, are briefly reviewed. PMID:20802570

  12. BRIEF COMMUNICATIONS: Use of a synchronously pumped picosecond laser for excitation of a spectrofluorimetric single-photon counting system

    NASA Astrophysics Data System (ADS)

    Ivanov, S. F.; Ostrovski?, A. V.; Pleshanov, P. G.; Turkin, K. A.; Fokin, V. S.; Sharov, Vyacheslav A.

    1983-08-01

    A nanosecond spectrofluorimeter for the counting of single photons emitted by a sample excited by laser pulses of 1.6-3.7 psec duration was used to determine the instrumental function of a PRA 3000 nanosecond spectrofluorimeter (half-width 0.62 ± 0.04 nsec at ? = 590-615 nm) and to investigate the operation of a picosecond laser with an acoustooptic deflector. It was found that the radiation emitted by a synchronously pumped dye laser with a pulse repetition frequency controlled by an acoustooptic deflector included not only the pulses of the expected frequency but also stray pulses at the pump frequency. Careful synchronization of the acoustooptic deflector pulses with the pump pulses made it possible to reduce the relative amplitude of the stray pulses from 30% to 0.3%.

  13. Laser emission from mixtures of dipyrromethene dyes in liquid solution and in solid polymeric matrices

    NASA Astrophysics Data System (ADS)

    Álvarez, M.; Amat-Guerri, F.; Costela, A.; García-Moreno, I.; Liras, M.; Sastre, R.

    2006-11-01

    Laser emission from binary mixtures of different dyes both in liquid solution and incorporated into solid polymeric matrices, covering the spectral region from green to red, is investigated. Mixtures of two synthesized dyes, analogs of the commercial dye Pyrromethene 567 (PM567), allowed covering the spectral range from green to orange. Tuning ranges in solid state of up to 42 nm with good photostabilities were demonstrated. To extend the tuning range to the red, binary mixtures of the dyes Pyrromethene 597 (PM597)/Pyrromethene 650 (PM650), PM567/DCM, and PM597/DCM were also studied. In liquid solution, a mixture of dyes PM567 and DCM allowed for narrow-linewidth laser emission continuously tunable over a range of 85 nm. In solid-state, mixtures of dyes PM597 and PM650 allowed laser emission tunable over two separate spectral regions up to a wavelength of 619 nm.

  14. Synthesis, structure, and physical properties of hybrid nanocomposites for solid-state dye lasers.

    PubMed

    García-Moreno, I; Costela, A; Cuesta, A; García, O; del Agua, D; Sastre, R

    2005-11-24

    We report on the synthesis, structural characterization, physical properties, and lasing action of two organic dyes, Rhodamine 6G (Rh6G) and Pyrromethene 597 (PM597), incorporated into new hybrid organic-inorganic materials, where the organic component was either poly(2-hydroxyethyl-methacrylate) (PHEMA) or copolymers of HEMA with methyl methacrylate (MMA), and the inorganic counterpart consisted of silica derived from hydrolysis-condensation of methyltriethoxysilane (TRIEOS) in weight proportion of up to 30%. Lasing efficiencies of up 23% and high photostabilities, with no sign of degradation in the initial laser output after 100 000 pump pulses at 10 Hz, were demonstrated when pumping the samples transversely at 534 nm with 5.5 mJ/pulse. A direct relationship could be established between the structure of the hybrid materials, analyzed by solid-state NMR, and their laser behavior. An inorganic network dominated by di-/tri- substituted silicates in a proportion approximately 35:65, corresponding to samples of HEMA with 15 and 20 wt % proportion of TRIEOS, optimizes the lasing photostability. The thermal properties of these materials, together with the high homogeneity revealed by atomic force microscopy (AFM) images, even in compounds with high silica content, indicate their microstructure to be a continuous phase, corresponding to the polymer matrix, which "traps" the silica components at molecular level via covalent bonding, with few or no silica islands. PMID:16853807

  15. Linewidth characteristics of Raman-shifted dye laser output at 720 and 940 nm

    NASA Technical Reports Server (NTRS)

    Grossmann, B. E.; Higdon, N. S.; Higdon, N. S.; Higdon, N. S.; Higdon, N. S.; Higdon, N. S.; Higdon, N. S.

    1986-01-01

    A compact and simple simultaneous multi-wavelength dye laser cavity was developed for a differential absorption technique. Dielectric multilayer interference filters were inserted inside the cavities as tuning elements, and two types of a DIAL system were constucted by using the dye laser tuned with dielectric multilayer filters to measure NO2 concentration. The usefulness of this dye laser was clarified for the differential absoroption technique in outdoor experiments. Some basic designs of the laser cavity with these filters to get simultaneously multi-wavelength output are summarized.

  16. Frequency measurements of optically pumped far-infrared laser lines

    SciTech Connect

    Telles, E.M.; Scalabrin, A.; Pereira, D. [Univ. Estadual de Campinas (Brazil). Inst. de Fisica] [Univ. Estadual de Campinas (Brazil). Inst. de Fisica

    1995-04-01

    In this work, the authors report the frequency measurements of optically pumped Far-Infrared (FIR) laser lines. They use the heterodyne technique of mixing FIR laser radiation and microwave radiation on a Metal-Insulator-Metal (MIM) point contact tunnel diode, to determine the FIR laser frequencies. The two FIR laser systems, consisting of CO{sub 2} waveguide pump lasers and Fabry-Perot FIR laser cavities, and MIM diode were developed by the authors. To check the system, they have measured some FIR laser line frequencies previously reported in the literature. An average fractional frequency reproducibility of {+-}7 {times} 10{sup {minus}7}, between their measurements and the previous ones, permit them to use their system to measure five new FIR laser frequencies.

  17. Sun-pump and lamp-pump Nd:YAG lasers for space communications

    Microsoft Academic Search

    D. Radecki; E. Reed; C. Chadwick

    1978-01-01

    This paper describes two versions of a mode-locked, internally frequency doubled Nd:YAG laser for use in a high data rate spaceborne optical communications system. The two versions are similar except for the method of optically pumping the rod. One is CW-pumped with an alkali-metal vapor arc lamp operating at 250 W input, while the other is pumped using sunlight collected

  18. Energy deposition measurements for e-beam pumped excimer lasers

    SciTech Connect

    Cates, M.C.; Robertson, K.L.; Melcher, P.C. (Maxwell Labs., Inc., San Diego, CA (USA)); Greene, D.P.; Romero, V.O. (Los Alamos National Lab., NM (USA))

    1989-01-01

    The energy deposition of the e-beam pumped MLI Two-Meter Laser was measured and compared using dosimetry films, electron calorimetry, current measurements, and pressure rise measurements. The measurements agreed within their uncertainties. 7 refs., 10 figs.

  19. Multiple pulses EUV laser pumping: ASE, seeded operations, and applications

    NASA Astrophysics Data System (ADS)

    Ros, D.; Kazamias, S.; Cassou, K.; Pittman, M.; Guilbaud, O.; Daboussi, S.; Delmas, O.; Demailly, J.; Neveu, O.; Mestrallain, A.; Sall, D.; Li, L.; Zeitoun, P.

    2013-10-01

    We present in this paper a laser-driven coherent EUV beamline resulting from the combination of a versatile high-order laser harmonic generator with a robust plasma-based EUV laser amplifier. Both devices can be used separetely or in synergy. Seeding of the plasma amplifier by a high-order harmonic beam leads to a strong improvement of the EUV laser beam divergence and uniformity. Moreover the system can be turned easily into a IR pump-XUV probe setup for plasma opacity probing. The possibility to generate two separate harmonic sources from the same gas cell offers the opportunity to explore EUV pump-EUV probe experiments.

  20. Low threshold visible electron-beam-pumped-lasers

    Microsoft Academic Search

    B. Fitzpatrick; J. Khurgin; P. Harnack; D. de Leeuw

    1986-01-01

    Electron-beam-pumped lasers (EBL) are small-target CRT's which are useful for projection displays, optical printing and PROMs, and optical mass-memory devices. Despite the obvious practical utility of a laser source with simple electronic scanning, applications of these devices have been held up by the high currents and, more importantly, high voltages necessary to achieve laser threshold. We have made ZnSe lasers

  1. Photophysical parameters and laser performance of 3-(4?-dimethylaminophenyl)-1-(2-furanyl)prop-2-en-1-one (DMAFP): A new laser dye

    NASA Astrophysics Data System (ADS)

    El-Daly, S. A.; Gaber, M.; El-Sayed, Y. S.

    2009-09-01

    The spectral properties such as singlet absorption, molar absorptivity, emission spectra, fluorescence quantum yield and excited state lifetime of 3-(4'-dimethylaminophenyl)-1-(2-furanyl)prop-2-en-1-one (DMAFP) have been determined in different solvents. DMAFP dye exhibits a large red shift in both electronic absorption and emission spectra as the solvent polarity increases, indicating a large change in the dipole moment of molecules upon excitation. A crystalline solid of DMAFP gives an excimer like emission at 566 nm due to the excitation of molecular aggregates. This is expected from the idealized crystal structure of the dye that belongs to the B-type class of Steven's classification. The ground and excited state protonation constants of DMAFP are calculated and amounted to 1.71 and 8.3, respectively. DMAFP acts as a good laser dye upon pumping with nitrogen laser ( ?ex=337.1 nm) in chloroform, methylene chloride and dioxane and gives laser emission in the range 460-590 nm. The laser parameters such as the tuning range, gain coefficient ( ?), emission cross section ( ? e) and half-life energy ( E1/2) are calculated. The photoreactivity and net photochemical quantum yield of DMAFP in chloromethane solvents are also studied.

  2. Modeling of diode pumped metastable rare gas lasers.

    PubMed

    Yang, Zining; Yu, Guangqi; Wang, Hongyan; Lu, Qisheng; Xu, Xiaojun

    2015-06-01

    As a new kind of optically pumped gaseous lasers, diode pumped metastable rare gas lasers (OPRGLs) show potential in high power operation. In this paper, a multi-level rate equation based model of OPRGL is established. A qualitative agreement between simulation and Rawlins et al.'s experimental result shows the validity of the model. The key parameters' influences and energy distribution characteristics are theoretically studied, which is useful for the optimized design of high efficient OPRGLs. PMID:26072754

  3. 600-W lamp pumped CW Nd:YAG laser

    NASA Astrophysics Data System (ADS)

    Li, Qiang; Wang, Zhimin; Wang, Zhiyong; Yu, Zhensheng; Lei, Hong; Guo, Jiang; Li, Gang; Zuo, Tiechuan

    2003-09-01

    A lamp pumped CW Nd:YAG laser is presented in this paper for the requirement of industrial application. The main factors, which affect output power and beam quality of high power solid-state laser module, are theoretically analyzed. Total electro-optics efficiency of lamp pumped Nd:YAG crystal as high as 4.0% is obtained, and output power is higher than 647 W with beam parameter product 22 mm·mrad.

  4. Photo-physical properties and quantum yield of some laser dyes in new polymer host

    NASA Astrophysics Data System (ADS)

    Al-Shamiri, Hamdan A. S.; Abou Kana, Maram T. H.; Azzouz, I. M.; Badr, Y. A.

    2009-06-01

    The field of laser dyes-active solid polymer materials is a promising field and quite competitive with liquid dye lasers. This paper investigates some photo-physical parameters of pyromethene (PM-567, PM-597) and Rhodamine B dyes incorporated into glycidyl methacrylate (GMA) promising polymeric host matrix. These parameters are: absorption and emission cross-sections, fluorescence lifetime and quantum yield, in addition to FT-Raman spectra as an indication for binding the dye molecules with the backbones of GMA polymeric chain.

  5. Remote chemical sensing by laser optical pumping

    SciTech Connect

    Stevens, C.G.; Magnotta, F.

    1996-08-01

    We are exploring a new approach to remote chemical identification that promises higher precision than can be achieved by conventional DIAL approaches. This technique also addresses and potentially solves the problem of detecting a target gas in the presence of an interfering gas or gases. This new approach utilizes an eye-safe infrared optical pumping pulse to deplete the population of a specific rotational level(s) and then sends probe pulses at the same or different wavelengths to interrogate the bleaching of the absorption. We have experimentally measured optical saturation fluence level at atmospheric pressure for HCl, and find this level to be {approximately}1 mJ/cm{sup 2}, significantly below eye-safe limits in agreement with calculations. Calculations have been performed on other molecules of interest with similar results. In the laboratory, using time-delay-replicated pulses at a single frequency we have made absorption measurements with precision levels routinely approaching 0.1% after averaging 200 laser pulses. These results as well as those of two other pulse experiments will be presented. 5 refs., 9 figs., 1 tab.

  6. Novel laterally pumped by prism laser configuration for compact solid-state lasers

    NASA Astrophysics Data System (ADS)

    Dascalu, T.; Salamu, G.; Sandu, O.; Voicu, F.; Pavel, N.

    2013-05-01

    We propose a new laser configuration in which the pump radiation is coupled into the laser crystal through a prism. The laser medium is square shaped and the prism is attached on one of its lateral sides, near one of the crystal extremities. The diode-laser fiber end is placed close to the prism hypotenuse, the pump radiation is coupled into the laser crystal through the opposite surface of the prism and propagates into the crystal through total internal reflections. This laser geometry is simple to align and permits the realization of compact diode-pumped laser systems, as well as power scaling. A diode-pumped Nd:YAG laser yielding pulses of 2.1 mJ energy under a pump with pulses of 9.9 mJ is demonstrated. The laser slope efficiency is 0.22. Furthermore, this geometry enables one to obtain passively Q-switched lasers with the saturable absorber crystal placed between the resonator high-reflectivity mirror and the laser crystal. A Nd:YAG laser, passively Q-switched by a Cr4+:YAG crystal with initial transmission T0 = 0.90, delivering laser output with a pulsed energy of 93 ?J, a duration of 26 ns and a pump threshold of 1.9 mJ, is realized in order to prove the concept.

  7. 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.

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

    SciTech Connect

    Barmashenko, B. D.; Rosenwaks, S. [Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel)] [Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel)

    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.

  9. 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.

  10. Abstract. A new combined cw single-frequency dye/Ti : sap-phire laser with a ring resonator located in the horizontal

    E-print Network

    Kobtsev, Sergei M.

    Abstract. A new combined cw single-frequency dye/Ti : sap- phire laser with a ring resonator conégurations. Keywords: continuous-wave single-frequency ring laser, dye laser, Ti : sapphire laser, laser now, only one combined cw single-frequency Ti : sapphire/dye ring laser was available (model 899

  11. Absolute tracer dye concentration using airborne laser-induced water Raman backscatter.

    PubMed

    Hoge, F E; Swift, R N

    1981-04-01

    Reported here for the first time is the use of simultaneous airborne laser-induced dye fluorescence and the 3400-cm(-1) OH-stretch water Raman backscatter spectra to yield the absolute concentration of an ocean-dispersed tracer dye. Using a straightforward theoretical model, the concentration is calculated by numerically comparing the airborne laser-induced fluorescence and Raman backscatter spectra to similar laboratory data for a known dye concentration measured under comparable environmental and instrumental conditions. The dye is assumed to be uniformly mixed throughout the water column together with other interfering, fluorescent, organic matter. A minimum detectable integrated water column dye concentration of approximately 2 ppb by weight as limited by background and instrument noise is obtained. A dye concentration contour map produced from the conical scan lidar data is given. PMID:20309284

  12. Ruggedized narrow-linewidth dispersive dye laser oscillator

    NASA Astrophysics Data System (ADS)

    Duarte, F. J.; Davenport, W. E.; Ehrlich, J. J.; Taylor, T. S.

    1991-08-01

    A ruggedized flashlamp-pumped multiple-prism grating oscillator is shown to yield output energies in the 2-3 mJ range at linewidths close to 300 MHz. The measured beam divergence was ?0.5 mrad. Wavelength stability was determined to be in the 4.63×10 -7-1.45×10 -6 range. The dispersive oscillator was constructed of super-invar for thermal and mechanical stability. The mechanical integrity of this cavity was tested in the field using vehicular displacement on a rugged terrain. Laser linewidth and beam quality characteristics of the dispersive oscillator were not affected adversely by the field test.

  13. 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.

  14. Modeling a diode pumped Nd: YAG rod laser

    NASA Astrophysics Data System (ADS)

    Shu, Hong; Chen, Ying; Bass, Michael; Acharekar, Madhu A.

    2006-02-01

    We evaluate the performance potential of a diode pumped Nd: YAG rod laser by finding the absorbed pump distribution using ASAP, pump induced thermal lensing, gain medium surface distortion and stresses using FEMLAB and depolarization losses using MATLAB. Beam propagation in the optically distorted Nd:YAG rod and the free space part of the cavity, and the output laser beam were determined with a computational scheme we developed which employs the beam propagation method combined with sparse matrix technology. We propose a special cavity design that can select the spatial eigen mode shape of the laser and simultaneously compensate for pump induced thermal lensing, gain medium surface distortion and birefringence. The converged solutions calculated this special cavity design give both high extraction efficiency and good output beam quality. Sensitivity of the output beam to mirror tilt, thermal induced mirror distortion, and errors in the cavity length or the optical distortions in the rod were also calculated.

  15. Quantum statistics of a squeezed-pump laser

    SciTech Connect

    Marte, M.A.; Ritsch, H.; Walls, D.F.

    1988-08-29

    A laser with squeezed-pump fluctuations is found to oscillate with one of two macroscopically distinct phases. The phase diffusion rate is reduced below that of the usual laser and the output light may have amplitude fluctuations reduced below the vacuum level.

  16. Research on solar pumped liquid lasers. Final Report

    Microsoft Academic Search

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

    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

  17. Reliability proving of 980 nm pump lasers for metro applications

    Microsoft Academic Search

    S. Arlt; H.-U. Pfeiffer; I. D. Jung; A. Jakubowicz; M. Schwarz; N. Matuschek; T. Pliska; B. Schmidt; S. Mohrdiek; C. S. Harder

    2002-01-01

    Reliability testing of pump lasers is based on accelerated life tests with different stress conditions. These tests are well established and their underlying principle is the scaling of the device lifetime with different stress conditions. The stress conditions have to be chosen in such a way that the aging of the laser chip is accelerated but no additional aging effects

  18. LaRC results on nuclear pumped noble gas lasers

    Microsoft Academic Search

    R. J. Deyoung

    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

  19. Analysis of direct nuclear pumped noble gas lasers

    Microsoft Academic Search

    J. E. Deese

    1978-01-01

    The model presented is applied to the He-3-Xe laser excited by the He-3(n,p) H-3 reaction. Predictions of the model are compared with experimental characteristics of this laser over a range of pressure, neutron flux, and xenon fraction. The dominant pumping mechanism appears to be collisional recombination of the Xe(+) ion.

  20. 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.

  1. Spectroscopy and efficient laser action from diode pumping of a new broadly

    E-print Network

    Boyer, Edmond

    Spectroscopy and efficient laser action from diode pumping of a new broadly tunable crystal: Yb3) and hence is of particular interest for diode-pumped femtosecond and tunable laser sources. Efficient operation from diode pumping (1.4 W of cw laser power obtained with 3.6 W of diode pump power and as much

  2. An optically pumped carbon monoxide laser operating at elevated temperatures

    NASA Astrophysics Data System (ADS)

    Ivanov, E.; Frederickson, K.; Leonov, S.; Lempert, W. R.; Adamovich, I. V.; Rich, J. W.

    2013-09-01

    A flowing gas, optically pumped, CO laser has been designed and built. The laser has been made to operate on the fundamental (?5 ?m) infrared bands of the CO vibrational states. The laser is powered by absorption of continuous wave radiation from an electric-discharge-excited CO laser. With this system, the kinetics of the establishment and maintenance of strong population inversions in CO at temperatures above 300 K is studied, independently of the complications of the electron impact processes and of other chemical channels which are present in electric discharge CO lasers. Lasing is obtained at temperatures up to 450 K, well above the cryogenic operating temperatures of conventional electric discharge CO lasers. The vibrational population distribution in the optically pumped laser is measured and the laser output power is determined as a function of the system operating parameters. Laser power conversion factors up to 14% have been observed. An optically pumped CO laser kinetic model is used to analyze the experimental results, providing insight into the details of secondary lasing kinetics.

  3. Development of diode lasers for pumping high power ultrashort pulse lasers

    Microsoft Academic Search

    Xingsheng Liu; Yishan Wang; Jingwei Wang; Entao Zhang; Lingling Xiong; Wei Zhao

    2009-01-01

    Summary form only given. Ultrashort pulse lasers have found increased applications in material processing with particular emphasis on laser-based micromachining applications, biomedical areas such as hard tissues ablating, and military fields. A new era of ultrashort pulse lasers was started when diode laser pumping gradually became more and more feasible, especially after the \\

  4. Combined guiding effect in the end-pumped laser resonator.

    PubMed

    Yan, Xingpeng; Liu, Qiang; Wang, Dongsheng; Gong, Mali

    2011-03-28

    A theoretical model as well as the experimental verification of the combined guiding mechanism for the transverse mode formation in the end-pumped laser resonator are investigated. The nonlinear Schrödinger-type wave equation in the gain medium is derived, in which the combined guiding mechanism: the thermal induced refractive index guiding effect as well as the gain guiding effect, is taken into account. The gain saturation and spatial hole burning are considered. The split step Fourier method is used to solve the nonlinear wave equation. A high power end-pumped Nd:YVO4 laser resonator is built up. After establishing the pump absorption model of our laser resonator, the temperature distribution in the gain medium is obtained by the numerical solving of the heat diffusion equation. The combined guiding effect is first observed in the end-pumped Nd:YVO4 laser resonator, and the experimental transverse mode profiles well agree with the theoretical prediction from the derived nonlinear Schrödinger-type wave equation. The geometric design criterion of the TEM00 mode laser is compared with our wave theory. The experimental- and theoretical- results show that our wave theory with the combined guiding mechanism dominates the transverse mode formation in high power end-pumped laser resonator. PMID:21451715

  5. First highly efficient and photostable E and C?derivatives of 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) as dye lasers in the liquid phase, thin films, and solid-state rods.

    PubMed

    Duran-Sampedro, Gonzalo; Esnal, Ixone; Agarrabeitia, Antonia R; Bañuelos Prieto, Jorge; Cerdán, Luis; García-Moreno, Inmaculada; Costela, Angel; Lopez-Arbeloa, Iñigo; Ortiz, María J

    2014-02-24

    A new library of E- and C-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) derivatives has been synthesized through a straightforward protocol from commercially available BODIPY complexes, and a systematic study of the photophysical properties and laser behavior related to the electronic properties of the B-substituent group (alkynyl, cyano, vinyl, aryl, and alkyl) has been carried out. The replacement of fluorine atoms by electron-withdrawing groups enhances the fluorescence response of the dye, whereas electron-donor groups diminish the fluorescence efficiency. As a consequence, these compounds exhibit enhanced laser action with respect to their parent dyes, both in liquid solution and in the solid phase, with lasing efficiencies under transversal pumping up to 73?% in liquid solution and 53?% in a solid matrix. The new dyes also showed enhanced photostability. In a solid matrix, the derivative of commercial dye PM597 that incorporated cyano groups at the boron center exhibited a very high lasing stability, with the laser emission remaining at the initial level after 100?000 pump pulses in the same position of the sample at a 10?Hz repetition rate. Distributed feedback laser emission was demonstrated with organic films that incorporated parent dye PM597 and its cyano derivative. The films were deposited onto quartz substrates engraved with appropriate periodical structures. The C derivative exhibited a laser threshold lower than that of the parent dye as well as lasing intensities up to three orders of magnitude higher. PMID:24453119

  6. 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.

  7. Development of a nanosecond-laser-pumped Raman amplifier for short laser pulses in plasma

    E-print Network

    Development of a nanosecond-laser-pumped Raman amplifier for short laser pulses in plasma Y. Ping,1 December 2009 Progress on developing a plasma amplifier/compressor based on stimulated Raman scattering limit of the pump intensity to avoid angular spray of the amplified seed has been determined. The Raman

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

    DOEpatents

    Savage-Leuchs; Matthias P. (Woodinville, WA)

    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.

  9. 250W diode laser for low pressure Rb vapor pumping

    Microsoft Academic Search

    A. Podvyaznyy; G. Venus; V. Smirnov; O. Mokhun; V. Koulechov; D. Hostutler; L. Glebov

    2010-01-01

    The diode pumped alkali vapor lasers operating at subatmospheric pressure require developing of a new generation of high-power laser diode sources with about 10 GHz wide emission spectrum. The latest achievements in the technology of volume Bragg gratings (VBGs) recorded in photo-thermo-refractive glass opened new opportunities for the design and fabrication of compact external cavity laser diodes, diode bars and

  10. Effect of flash lamp pulsed dye laser on discoid lupus erythematosus lesions

    Microsoft Academic Search

    Mona Soliman; Hesham Shokir; Samia Gabal; Abeer Attia

    2006-01-01

    The treatment of discoid lupus erythematosus with pulsed dye has been evaluated in recent years. The improvement of telangiectasia and erythema in cutaneous lesions was based on selective photothermolysis ablation of the dilated capillaries and venules .While the improvement in scar and atrophy was referred to the effect of pulsed dye laser on collagenase activity. We describe the results of

  11. Study of the mechanisms of laser-induced release of liposome-encapsulated dye

    SciTech Connect

    Khoobehi, B.; Char, C.A.; Peyman, G.A.; Schuele, K.M. (Louisiana State Univ. Medical Center, School of Medicine, New Orleans (USA))

    1990-01-01

    To differentiate the contributing factors (blood or encapsulated dye) leading to the release of encapsulated dyes from liposomes after laser exposure, we initiated an in vitro experimental study. The release of encapsulated calcein was quantified under various experimental conditions in whole blood and in buffered solution containing high-density lipoprotein. Generally, the amount of dye release improved with an increase in laser power, with a maximum release of approximately 80% of encapsulated dye. Because the laser exposure was not continuous, only 80% of each sample was actually exposed. Therefore, 80% release may be thought of as total release. In a lipoprotein/buffer mixture, the 488 nm wavelength caused greater dye release than the 577 nm wavelength, because the maximum absorption of calcein is near 488 nm. The laser wavelength at 577 nm, however, caused greater release in the blood mixture, reflecting the peak absorption of hemoglobin at near 577 nm. At a 3 x higher liposome concentration, the differences in the effects of wavelengths on the release of dye from liposomes were insignificant. Although the 577 nm wavelength is an optimum wavelength for dye and drug delivery in the presence of blood, the 488 nm wavelength might also be suitable for the release of dye from the liposomes.

  12. High-stability LD-pumped solid state laser

    NASA Astrophysics Data System (ADS)

    Yan, Ping; He, Bin; Wei, Guang Hui

    1999-05-01

    In high power laser systems, the stability of the seed laser is vitally important. This paper focuses on work undertaken to design and make a high stable LD pumped solid state seed laser which had the advantage of being all solid state, compact, easy to manufacture and low cost. The laser was composed of two parts. One part was a LD pumped 0.5 mm thick Nd:YLF laser system in which the instability was around +/- 6% (3(sigma) ). The other part was a close-looped laser power control system using external cavity power feedback. Using an electro-optic modulator, a 1 X 2 optical fiber splitter and a signal processing circuit, we successfully realized the high stable LD pumped Nd:YLF laser in which the instability of laser output power was lower than +/- 0.2%/hour (3(sigma) ). A digital PID control method was used in which the control frequency was 40 kHz. We obtained 3 mW of high stability laser power through the optical fiber.

  13. Comparison of the flashlamp pulsed dye laser with the argon tunable dye laser with robotized handpiece for facial telangiectasia.

    PubMed

    Ross, M; Watcher, M A; Goodman, M M

    1993-01-01

    This prospective study compares the efficacy, side effects, and patient acceptance of the flashlamp pulsed dye laser (FPDL) with the argon tunable dye laser with robotized handpiece (ATDL/H) for facial telangiectasias. Seventeen adult patients with bilaterally symmetric facial telangiectasias were enrolled. The right cheek on each patient was treated in one session with the FPDL at a fluence of 6.0-6.75 J/cm2 and a spot size of 5 mm. The left cheek was treated at the same session with the ATDL/H at a power of 1 W, a fluence of 26-27 J/cm2, and a hexagonal treatment area of 13 mm (127 individual 1 mm spots grouped mechanically by the handpiece). Patients were evaluated subjectively and by the investigators at 2, 4, and 6 weeks for blistering, swelling, bruising, changes in pigment, scarring, overall efficacy, and patient preference. Average treatment times were 5.4 minutes for FPDL and 9.4 minutes for ATDL/H. Blistering, crusting, and discomfort were completely resolved on both sides by week 2 in all patients. Bruising occurred in all patients with FPDL but had resolved in 62.5% of patients at 2 weeks and 100% at 4 weeks. There was no bruising with ATDL/H. Postinflammatory hyperpigmentation was much more prominent with FPDL but had resolved in 88% of cases by week 6. As rated by the investigators 100% of the FPDL treated areas showed excellent clearing of telangiectasias, compared with 47% of ATDL/H treated areas.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8515677

  14. 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-?m wavelength region, opening up a new way to scale the output power of the 2-?m fiber laser to new levels (e.g. 10 kW). Using a 1942 nm Tm3+ fiber laser as the pump source with the co- (counter-) propagating configuration, the 2020 nm Tm3+ 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-?m Tm3+-doped fiber lasers, and the highest output power for all-fiber tandem-pumped 2-?m fiber oscillators. This system fulfills the complete structure of the proposed cascaded tandem pumping technique in the 2-?m 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

  15. Multi-wavelength laser from dye-doped cholesteric polymer films

    E-print Network

    Wu, Shin-Tson

    GHz pulse train generation from semiconductor amplifier fiber ring laser," IEEE Photon. Technol. Lett. Wysocki, "24-Line multiwavelength operation of Erbium-Doped fiber-Ring laser," IEEE Photon. Technol. LettMulti-wavelength laser from dye-doped cholesteric polymer films Yuhua Huang1,2,* and Shin-Tson Wu2

  16. Volume172,number 3,4 CHEMICALPHYSICSLETTERS 7September 1990 Cavity ring down dye laser spectroscopy

    E-print Network

    Cohen, Ronald C.

    Volume172,number 3,4 CHEMICALPHYSICSLETTERS 7September 1990 Cavity ring down dye laser spectroscopy-phasemetal dimer systemshavebeen spectrallycharacterizedusingres- onant two-photon ionization (R2PI) and laser thus seems uniquely suitable for the study of laser vaporized metal clusters. 2. Experimental

  17. Enhancing the laser power by stacking multiple dye-doped chiral polymer films

    E-print Network

    Wu, Shin-Tson

    . Ozaki, "High Q defect mode and laser action in one-dimensional hybrid photonic crystal containing, and S. Mashiko, "Phototunable photonic bandgap in a chiral liquid crystal laser device," Appl. Phys in the backward direction than the forward one. This is due to the absorption of the laser dyes

  18. Continuous-wave diode-pumped solid-state laser with an intracavity fiber Bragg grating

    E-print Network

    Paris-Sud XI, Université de

    to stabilize the laser emission by spectrally narrowed self-injection. Antireflection-coated diode lasersContinuous-wave diode-pumped solid-state laser with an intracavity fiber Bragg grating Sylvie Yiou concept of laser that benefits from both fiber and laser crystals: a cw diode-pumped solid-state laser

  19. Efficient sintering of nanocrystalline titanium dioxide films for dye solar cells via raster scanning laser

    Microsoft Academic Search

    Girolamo Mincuzzi; Luigi Vesce; Andrea Reale; Aldo di Carlo; Thomas M. Brown

    2009-01-01

    By identifying the right combination of laser parameters, in particular the integrated laser fluence Phi, we fabricated dye solar cells (DSCs) with UV laser-sintered TiO2 films exhibiting a power conversion efficiency ?=5.2%, the highest reported for laser-sintered devices. ? is dramatically affected by phi and a clear trend is reported. Significantly, DSCs fabricated by raster scanning the laser beam to

  20. Treatment of poikiloderma of Civatte with the pulsed dye laser: a series of seven cases.

    PubMed

    Haywood, R M; Monk, B E

    1999-01-01

    Seven patients with poikiloderma of Civatte were treated successfully with the pulsed dye laser. One patient's treatment was complicated by scarring, which appeared 4 months after the treatment. PMID:11360425

  1. 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.

  2. End-pumped continuous-wave alkali vapor lasers: experiment, model, and power scaling

    Microsoft Academic Search

    Raymond J. Beach; William F. Krupke; V. Keith Kanz; Stephen A. Payne; Mark A. Dubinskii; Larry D. Merkle

    2004-01-01

    End-pumped alkali vapor lasers excited on their D2 transition and lased on their D1 transition offer a pathway to high average power that potentially competes with diode-pumped solid-state lasers in many applications that require cw or quasi-cw laser operation. We report on the first experimental demonstration of an end-pumped Cs laser using a Ti:sapphire laser for pump excitation. Detailed experimental

  3. Invasive leg vein treatment with 1064/1319 Nd:YAG laser: combination with dye laser treatment

    NASA Astrophysics Data System (ADS)

    Smucler, Roman; Horak, Ladislav; Mazanek, Jiri

    1999-06-01

    More than 2 500 leg veins patients were treated with dye laser / ScleroPlus, Candela, USA / successfully in our clinic and we use this therapy as the basic cosmetics treatment. But especially diameter of leg vein is limiting factor. Very often we have to treat some cases that are not ideal for classical surgical or for dye laser method. We decided to make invasive perivenous laser coagulation. We adapted original Czech 1064/1319 nm Nd:YAG laser / US patent pending /, which is new combine tool, for invasive application. Principe: After we have penetrated the cutis with laser fiber we coagulate leg veins during slowly perivenous motion. Perfect preoperative examination is a condition of success. After 15 months we have very interesting results. Some patients / 15%/ were perfect treated only with this possibility but excellent results are acquired from combination with dye laser.

  4. LASERS: Physical aspects of constructing a nuclear-pumped solid-state laser

    NASA Astrophysics Data System (ADS)

    Seregin, A. A.; D'yachenko, P. P.; Lapidus, V. I.; Seregina, E. A.

    1999-02-01

    An investigation is reported of the physical aspects of the feasibility of constructing a nuclear-pumped solid-state laser. The active media considered for such a laser include neodymium-activated uranyl-doped crystals of yttrium aluminium garnet and several types of silicate and phosphate glasses. It is shown that the laser action in yttrium aluminium garnet and in two types of phosphate glasses may be observed when pumping is provided by the pulsed BARS-6 reactor.

  5. Effects of detergents, viscosity modifiers, and temperature differential on the output of certain laser dyes

    NASA Astrophysics Data System (ADS)

    Kubin, R. F.; Fletcher, A. N.; Pietrak, M. C.; Bliss, D. E.

    The effects of the addition of viscosity modifiers and detergents and control of the coolant-dye solution temperature differential on the performance of flashlamp pumped dyes are evaluated. The fluorescence quantum yield of rhodamine 6G was measured in various concentrations of the viscosity modifer Klucel H in a water-alcohol solvent. The addition of sodium dodecylsulfate to water solutions of certain pyridinium oxazole salts was shown to increase the lasing output by factors of two to greater than ten.

  6. Diode-pumped UV refractive surgery laser

    NASA Astrophysics Data System (ADS)

    Lin, Jui T.; Hwang, Ming-Yi; Huang, C. H.

    1993-07-01

    Ophthalmic applications of medical lasers have been extensively explored recently because of their market potential. Refractive surgical lasers represent one of the major development efforts due to the large population of eye disorders: about 160 million people in the USA and more than 2 billion worldwide. The first refractive laser developed was the ArF excimer laser at 193 nm in 1987 - 88 for a procedure called photorefractive keratectomy (PRK). More recently, solid state refractive lasers have also been explored for preliminary clinical trials. These lasers include Nd:YLF (picosecond at 1054 nm), doubled-Nd:YAG (nanosecond at 532 nm), Ho:YAG (microsecond at 2100 nm) and ultraviolet (UV) lasers generated from the harmonic of Ti:sapphire-laser (205 - 220 nm) and Nd:YAG (at 213 nm).

  7. Developing a narrow-line laser spectrometer based on a tunable continuous-wave dye laser.

    PubMed

    Wang, Chun; Lv, Shasha; Liu, Fang; Bi, Jin; Li, Liufeng; Chen, Lisheng

    2014-08-01

    We present the development of a dye-laser-based spectrometer operating at 550-600 nm. The spectrometer will be used to detect an ultra-narrow clock transition ((1)S0-(3)P0) in an Ytterbium optical lattice clock and perform high-resolution spectroscopy of iodine molecules trapped in the sub-nanometer channels of zeolite crystal (AlPO4-11). Two-stage Pound-Drever-Hall frequency stabilization is implemented on the tunable continuous-wave dye laser to obtain a reliable operation and provide stable laser radiations with two different spectral linewidths. In the first-stage frequency locking, a compact home-built intracavity electro-optic modulator is adopted for suppressing fast frequency noise. With an acquisition time of 0.1 s the 670-kHz linewidth of the free-running dye laser is reduced to 2 kHz when locked to a pre-stabilization optical cavity with a finesse of 1170. When the pre-stabilized laser is locked to a high-finesse optical cavity, a linewidth of 1.4 Hz (2 s) is observed and the frequency stability is 3.7 × 10(-15) (3 s). We also measure and analyze the individual noise contributions such as those from residual amplitude modulation and electronic noise. The ongoing upgrades include improving long-term frequency stability at time scales from 10 to 100 s and implementing continuous frequency scan across 10 GHz with radio-frequency precision. PMID:25173252

  8. Tandem-pumped 1120-nm actively Q-switched fiber laser

    NASA Astrophysics Data System (ADS)

    Wang, Jian-Hua; Hu, Jin-Meng; Zhang, Shi-Qiang; Chen, Lu-Lu; Fang, Yong; Feng, Yan; Li, Zhi

    2015-02-01

    We report on a tandem-pumped actively Q-switched fiber laser system emitting at 1120 nm. Parasitic oscillation is challenging in Yb-doped Q-switched 1120-nm fiber laser, which is suppressed by pumping with a fiber laser at 1018 nm. At least four times improvement in output peak power is demonstrated in a single laser setup with 1018-nm fiber laser pumping instead of 976-nm laser diode pumping. This is, to the best of our knowledge, the first demonstration of a tandem-pumped Q-switched fiber laser.

  9. Dynamics of a detuned, optically pumped far-infrared laser

    Microsoft Academic Search

    J. Pujol; F. Laguarta; R. Corbalan; R. Vilaseca

    1988-01-01

    The dynamic behaviour of a coherently pumped single-mode far-infrared ring laser with a homogeneously broadened three-level medium is analysed theoretically, considering detuning between amplifying transition and cavity frequencies. Phase diagrams as a function of cavity detuning and amplitude of the resonant pump field have been obtained, which show different domains of stationary, oscillatory and chaotic output. In some conditions the

  10. Stable doped hybrid sol-gel materials for solid-state dye laser.

    PubMed

    Nhung, Tran H; Canva, Michael; Dao, Truong T A; Chaput, Frédéric; Brun, Alain; Hung, Nguyen D; Boilot, Jean-Pierre

    2003-04-20

    Laser effects have been obtained with dye-doped hybrid xerogel samples prepared several years ago and stored in different "classical" conditions. Firstly, using the same configuration of the laser cavity as was used 4-5 years ago, we have obtained almost identical laser performances, and slope conversion efficiencies were measured up to 80% and operational lifetimes, with 1-mJ initial output energy and 10-Hz repetition rate of several hundred thousand pulses obtained. Secondly, we have introduced the new pyrromethene 605 dye into a hybrid xerogel matrix and obtained good laser performances similar to the rest of the pyrromethene family. PMID:12716164

  11. Improved temperature precision in rotational coherent anti-Stokes Raman spectroscopy with a modeless dye laser

    NASA Astrophysics Data System (ADS)

    Vestin, Fredrik; Afzelius, Mikael; Bengtsson, Per-Erik

    2006-02-01

    Single-shot thermometry with dual-broadband rotational coherent anti-Stokes Raman spectroscopy that employs amplified spontaneous emission from a broadband modeless dye laser has been examined. Evaluation of single-shot spectra of air, N2, and O2 showed an improved temperature precision at room temperature compared with the precision obtained with a conventional dye laser. A comparison was also made between the use of single-mode and multimode Nd:YAG lasers as sources for narrowband radiation, and in all cases the single-mode Nd:YAG laser resulted in higher precision. The experimental results are compared with theoretical predictions.

  12. Improved temperature precision in rotational coherent anti-stokes raman spectroscopy with a modeless dye laser.

    PubMed

    Vestin, Fredrik; Afzelius, Mikael; Bengtsson, Per-Erik

    2006-02-01

    Single-shot thermometry with dual-broadband rotational coherent anti-Stokes Raman spectroscopy that employs amplified spontaneous emission from a broadband modeless dye laser has been examined. Evaluation of single-shot spectra of air, N2, and O2 showed an improved temperature precision at room temperature compared with the precision obtained with a conventional dye laser. A comparison was also made between the use of single-mode and multimode Nd:YAG lasers as sources for narrowband radiation, and in all cases the single-mode Nd:YAG laser resulted in higher precision. The experimental results are compared with theoretical predictions. PMID:16485686

  13. Highly photo-stable dye doped solid-state distributed-feedback (DFB) channeled waveguide lasers by a pen-drawing technique.

    PubMed

    Yang, Yu; Goto, Ryo; Omi, Soichiro; Yamashita, Kenchi; Watanabe, Hirofumi; Miyazaki, Masaya; Oki, Yuji

    2010-10-11

    Pyrromethene dyes doped polymeric channeled waveguide lasers with permanent DFB structures were fabricated via a novel pen-drawing technique with the patterned polydimethylsiloxane (PDMS) chips fabricated through a casting process as the substrates. With the high resolution dispensers, dye doped high viscosity pre-polymers were written into the PDMS grooves and the cross-section of the channeled waveguides could be controlled by both the polymer composition and the pen-drawing parameters. Highly stable laser output with 4.8 × 10(6) pulses of laser lifetime at 500 Hz of pump repetition rate has been obtained, which is suggested to be among one of the best results of pyrromethene 567 (PM567) up to date. PMID:20941109

  14. Operating temperature of diode-pumped alkali vapor laser

    NASA Astrophysics Data System (ADS)

    Zhu, Qiang; Yu, Jianhua; Zheng, Wei; Quan, Hongyan

    2008-03-01

    Diode-pumped alkali vapor laser (DPAL) is a new class of laser, and it is expected to realize high efficiency and high-average-power laser with good beam quality (near-diffraction-limited). DPAL offers CW laser radiation at near-infrared wavelengths and can find a lot of applications in power beaming, drilling oil and gas well and laser material processing. Operating temperature affects not only the density of alkali vapor atom in active region, but collision broadening and fine-structure mixing rate. In this paper, we study the operating temperature characteristics of DPAL. Based on the theory of quasi-three level CW laser, the dependence of cesium laser output power on the operating temperature has been simulated. The results showed that there exists an optimal operating temperature around 95 to 110 centigrade for high pumping power. In lower temperature region, the laser power rise linearly with increasing operating temperature, namely increasing active density. However, the laser power falls after the optimal operating temperature, because the spontaneous radiations deplete large numbers of stimulated population contributing to laser emissions. At the optimal temperature, an optical- optical efficiency of about 73% is able to reach theoretically.

  15. 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., E-mail: grant.ritchie@chem.ox.ac.uk [Department of Chemistry, Physical and Theoretical Chemistry Laboratory, The University of Oxford, South Parks Road, Oxford (United Kingdom)] [Department of Chemistry, Physical and Theoretical Chemistry Laboratory, The University of Oxford, South Parks Road, Oxford (United Kingdom); Weidmann, Damien [Space Science and Technology Department, STFC Rutherford Appleton Laboratory, Harwell Oxford Campus, Didcot OX11 0QX (United Kingdom)] [Space Science and Technology Department, STFC Rutherford Appleton Laboratory, Harwell Oxford Campus, Didcot OX11 0QX (United Kingdom)

    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 ?m. 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 ?s 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.

  16. Pump-Controlled Directional Light Emission from Random Lasers

    NASA Astrophysics Data System (ADS)

    Hisch, Thomas; Liertzer, Matthias; Pogany, Dionyz; Mintert, Florian; Rotter, Stefan

    2013-07-01

    The angular emission pattern of a random laser is typically very irregular and difficult to tune. Here we show by detailed numerical calculations that one can overcome the lack of control over this emission pattern by actively shaping the spatial pump distribution. We demonstrate, in particular, how to obtain customized pump profiles to achieve highly directional emission. Going beyond the regime of strongly scattering media where localized modes with a given directionality can simply be selected by the pump, we present an optimization-based approach which shapes extended lasing modes in the weakly scattering regime according to any predetermined emission pattern.

  17. Graphene surface emitting terahertz laser: Diffusion pumping concept

    SciTech Connect

    Davoyan, Arthur R., E-mail: davoyan@seas.upenn.edu [Kotelnikov Institute of Radio Engineering and Electronics (Saratov Branch), Russian Academy of Sciences, Saratov 410019, Russia and Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Morozov, Mikhail Yu.; Popov, Vyacheslav V. [Kotelnikov Institute of Radio Engineering and Electronics (Saratov Branch), Russian Academy of Sciences, Saratov 410019 (Russian Federation)] [Kotelnikov Institute of Radio Engineering and Electronics (Saratov Branch), Russian Academy of Sciences, Saratov 410019 (Russian Federation); Satou, Akira; Otsuji, Taiichi [Research Institute of Electrical Communication (RIEC), Tohoku University, Sendai, Miyagi 980-8577 (Japan)] [Research Institute of Electrical Communication (RIEC), Tohoku University, Sendai, Miyagi 980-8577 (Japan)

    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.

  18. A flashlamp-pumped 946 nm Nd:YAG laser

    NASA Astrophysics Data System (ADS)

    Dimov, S.; Peik, E.; Walther, H.

    1991-07-01

    Generation of 946 nm radiation from a commercially available, flashlamp-pumped Nd:YAG laser was investigated. By suppression of the high-gain 1.064 ?m transition and with a specially designed cooling system, a stable emission at 946 nm was achieved in the temperature range 300 240 K. At a repetition rate of 10 Hz laser output powers of 100mW and 500 mW were obtained at room temperature and 240 K respectively. The temperature dependence of unsaturated gain, slope efficiency and pumping threshold were determined.

  19. A flashlamp-pumped 946 nm Nd:YAG laser

    NASA Astrophysics Data System (ADS)

    Dimov, S.; Peik, E.; Walther, H.

    1991-07-01

    Generation of 946 nm radiation from a commercially available, flashlamp-pumped Nd:YAG laser was investigated. By suppression of the high-gain 1.064-micron transition and with a specially designed cooling system, a stable emission at 946 nm was achieved in the temperature range 300-240 K. At a repetition rate of 10 Hz laser output powers of 100 mW and 500 mW were obtained at room temperature and 240 K, respectively. The temperature dependence of unsaturated gain, slope efficiency and pumping threshold were determined.

  20. Conceptual Design Studies of a Laser Diode Pumped Solid State Laser System for the Laser Fusion Reactor Driver

    Microsoft Academic Search

    Kenta Naito; Masanobu Yamanaka; Masahiro Nakatsuka; Tadashi Kanabe; Kunioki Mima; Chiyoe Yamanaka; Sadao Nakai

    1992-01-01

    We have developed a conceptual designing technique of a laser diode pumped solid state laser system having high peak power, high efficiency, good beam quality, and high repetition rate. Using this technique, we evaluated the feasibility of the systems with several solid state laser materials for the laser fusion reactor driver with 10 MJ blue output, 10% overall efficiency, and

  1. Electron beam pumped KrF lasers for fusion energy

    NASA Astrophysics Data System (ADS)

    Sethian, J. D.; Friedman, M.; Giuliani, J. L.; Lehmberg, R. H.; Obenschain, S. P.; Kepple, P.; Wolford, M.; Hegeler, F.; Swanekamp, S. B.; Weidenheimer, D.; Welch, D.; Rose, D. V.; Searles, S.

    2003-05-01

    In this paper, we describe the development of electron beam pumped KrF lasers for inertial fusion energy. KrF lasers are an attractive driver for fusion, on account of their demonstrated very high beam quality, which is essential for reducing imprint in direct drive targets; their short wavelength (248 nm), which mitigates the growth of plasma instabilities; and their modular architecture, which reduces development costs. In this paper we present a basic overview of KrF laser technology as well as current research and development in three key areas: electron beam stability and transport; KrF kinetics and laser propagation; and pulsed power. The work will be cast in context of the two KrF lasers at the Naval Research Laboratory, The Nike Laser (5 kJ, single shot), and The Electra Laser (400-700 J repetitively pulsed).

  2. 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.

  3. Diode-Pumped Mode-Locked LiSAF Laser

    SciTech Connect

    None

    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.

  4. Performance of a Ho:YAG thin-disc laser pumped by a diode-pumped 1.9 ?m thulium laser

    Microsoft Academic Search

    M. Schellhorn

    2006-01-01

    The lasing performance of a Ho:YAG thin-disc laser pumped by a diode-pumped 1.9 ?m thulium laser was examined. A cw output power of 9.4 W was obtained, corresponding to a slope efficiency with respect to incident pump power of 40% and an optical-to-optical efficiency of 36%.

  5. Comparison of the Effectiveness of Nonablative Fractional Laser versus Pulsed-Dye Laser in Thyroidectomy Scar Prevention

    PubMed Central

    Ha, Ji Min; Kim, Han Su; Cho, Eun Byul; Park, Gyeong Hun; Kim, Kwang Ho; Kim, Lee Su; Kim, Kwang Joong

    2014-01-01

    Background The anterior neck is the site of open thyroidectomy and where postoperative scarring can cause distress to patients. Both fractional and pulsed-dye lasers are effective and safe methods for preventing and improving surgical scars. Objective This study evaluated the improvement in scar appearance with laser intervention during the wound healing process. We evaluated the effect of nonablative fractional and pulsed-dye lasers on fresh thyroidectomy scars. Methods Patients were treated 3 times at 4-week interval with a follow-up visit at the 6th month. Scars were divided into 2 halves for each optional treatment. At every visit, a questionnaire evaluating the scar and patient satisfaction was completed. Results Thirty patients completed the 6-month process. The mean Vancouver Scar Scale scores improved significantly from 8.0 to 4.6 and 8.2 to 4.7 with nonablative fractional and pulsed-dye lasers, respectively (p<0.001). However, there was no significant difference between the 2 methods (p=0.840). Conclusion There remains no consensus on the optimal treatment of scars. The present study indicates nonablative fractional and pulsed-dye lasers significantly improve scars. Nonablative fractional lasers are non-inferior to pulsed-dye lasers. Further studies are required to corroborate this finding. PMID:25324655

  6. Design and performance of a few-kilohertz-linewidth dye laser stabilized by reflection in an optical resonator

    Microsoft Academic Search

    Marie Houssin; Michèle Jardino; Bruno Gely; Michel Desaintfuscien

    1988-01-01

    Ultrahigh-resolution spectroscopy is limited by the spectral quality of lasers. We describe a servo system that stabilizes a dye laser by reflection in an optical resonator, which provides an error signal. We analyze the error signal to determine the spectral performance of the dye laser, which is shown to have a Gaussian-shaped spectrum with a width of less than 4

  7. Mechanism of dye-enhanced enamel ablation by Alexandrite laser radiation

    NASA Astrophysics Data System (ADS)

    Esenaliev, Rinat O.; Oraevsky, Alexander A.; Motamedi, Massoud; Rastegar, Sohi; Tittel, Frank K.

    1995-05-01

    Insufficient light absorption in hard dental tissues makes laser ablation in near UV, visible or near IR spectral ranges very inefficient to be employed for tooth cavity preparations. We used deposition of a liquid absorber, indocyanine green (ICG) dye, to overcome this problem. Experiments employed Alexandrite laser anticipating that future near IR diode laser technology will replace existing medical lasers. Ablation kinetics and mechanisms for both free-running and Q-switched modes of Alexandrite laser were studied with the aim to determine optimal parameters of laser irradiation and optimal volume of the dye. Four experimental parameters were monitored during each ablation event: (1) incident laser fluence, (2) temporal profile of the laser pulse, (3) temporal profile and magnitude of laser-induced stress transients, (4) temporal profile and spectrum of plasma emission. We also examined kinetics of plume by probing ablation products with CW He-Ne laser beam. Results depicted ablation process as a complex multistage phenomenon. Two distinct stages associated with the tooth ablation are revealed in the free-running mode: (1) ablation of a dye droplet from a tooth surface by the first laser micropulse of a 250-microsecond(s) macropulse, (2) plasma mediated ablation of a melted layer of enamel produced by thermal explosion of the dye. Plasma jet formation was delayed 10-100 microsecond(s) against the beginning of free-running pulse. Ablation stages and their efficiency are defined by laser irradiation parameters, dye concentration and its total volume. In contrast, Q-switched (nanosecond) laser ablation occurs as a one stage process, and, therefore, less efficient. In addition, Q-switched mode irradiation induces shock waves amplitudes that are about an order of magnitude higher compared with that induced by the free-running irradiation. Experimental comparison of Q-switched and free-running modes of irradiation is evident in favor of free-running mode that produces a nice smooth crater without noticeable thermomechanical damage to surrounding tissues.

  8. Star couplers with gain using multiple erbium-doped fibers pumped with a single laser

    Microsoft Academic Search

    A. E. Willner; A. A. M. Saleh; H. M. Presby; D. J. DiGiovanni; C. A. Edwards

    1991-01-01

    An economical method for combining erbium-doped fiber (EDF) amplifiers and star couplers, is presented. It involves simultaneously pumping EDFs placed at the input or output ports of the coupler with a single laser pump source distributed through the coupler itself. In this way, many amplifiers can share the cost of a single pump laser, and the need for individual pump\\/signal

  9. ACTIVE MEDIA: Relation between spectral and lasing properties for dyes of different classes

    NASA Astrophysics Data System (ADS)

    Koldunov, M. F.; Kravchenko, Ya V.; Manenkov, Aleksandr A.; Pokotilo, I. L.

    2004-02-01

    The lasing efficiency and the service life of pyrromethene and phenalemine dyes doped to nanoporous glass-polymer composites are studied upon monochromatic laser pump. The absorption and luminescence spectra of these dyes are investigated. The spectral parameters of the dyes determining their lasing efficiency are found from the analysis of their spectra and lasing characteristics, and the dyes are classified according to their lasing efficiency. A correlation between the lasing efficiency and the service life of laser elements is also established.

  10. LD dual-end-pumped CW Tm:YLF laser

    NASA Astrophysics Data System (ADS)

    Chen, Xin-yu; Zhang, Yu; Yu, Yong-ji; Wang, Chao; Jin, Guang-yong

    2013-09-01

    We report on a LD dual-end-pumped 792nm continuous wave operation Tm:YLF laser. Firstly, the rate equation of LD end-pumped CW operation Tm:YLF laser were established, in which the energy transfer upconversion and without energy transfer upconversion under continuous-wave considerate were considered, as well the pump threshold and the slope efficiency of the laser system were analyzed. Simultaneously, the cavity stability condition and the pattern matching of the plano- concave resonator were analyzed according to ABCD Matrix theory. Comparing respectively the laser threshold and the slope efficiency and optical-optical conversion efficiency under circumstances which the output mirror transmittance of 15% and 23%. In addition, the M2 of the output laser were contrasted and analyzed in adjusting the resonator cavity length by using different radius of curvature of the output mirror in 150mm, 200mm and 300mm all in the above case. As the process of thermal lens focal length changing greater than 90mm, it exhibited that the two fundamental modes in the cavity resonator matched well in numerical simulation when the radius of curvature of the output mirror was 300mm, as well the two fundamental modes matched well when it more than 100mm in a certain pump power. We designed a single LD dual-end-pumped continuous wave operation Tm:YLF laser. Using Tm:YLF (3 at.%) crystal for gain medium, which the size was 3×3×14mm3. In experiments, the Tm:YLF laser crystal keeps 291K and the temperature control method is water cooling. The length of the resonator was 135mm when L shape plano-concave resonator was applied, and the radius of curvature output mirror was 300mm, as well as the temperature of the Tm:YLF laser crystal was 291K. The output laser we observed by this system and the central laser wavelength was 1944nm. The threshold power was 8.11W and the highest output power reaches to 4.01W when the totally input pump power was 17W, and the optical conversion efficiency was 23.6%. The far-field divergence angle was 3.8mrad after calculation. Respectively. The experimental results are coinciding with the theory.

  11. Demonstration of triple pump coherent anti-Stokes Raman scattering in a jet diffusion flame

    E-print Network

    Velur Natarajan, Viswanathan

    2002-01-01

    . A. Theory 1. Coherent anti-Stokes Raman scattering basics B. Dual-pump and triple-pump CARS processes 1. Dual-pump CARS 2. Triple pump CARS C. Thermometry and species detection EXPERIMENTAL APPARATUS A. Initial experimental system 1. Laser.... Laser Alignment and Performance I . Nd: YAG laser 2. Narrow band dye laser (ND6000) alignment 3. Broad-band dye laser alignment B. Triple-pump CARS set-up 1. CARS phase-matching alignment 2. Diffusion flame burner C. Results I. Results from first...

  12. Optically pumped CW (Continuous Wave) semiconductor ring laser

    Microsoft Academic Search

    M. M. Salour; A. Fuchs; D. Bebelaar

    1986-01-01

    This patent discloses an optically pumped semiconductor ring laser having a plurality of reflective elements optically aligned with one another to form a ring-shaped resonant cavity. A semiconductor lasing medium is mounted within the ring-shaped resonant cavity by a transparent, heat conductive mount located within a vacuum\\/cooling chamber of the type which allows the passage of a laser beam therethrough.

  13. 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.

  14. Analysis of temperature distributions in diode-pumped alkali vapor lasers

    Microsoft Academic Search

    Qi Zhu; Bailiang Pan; Li Chen; Yajuan Wang; Xunyi Zhang

    2010-01-01

    Assuming the pump light to be a Gaussian beam and considering the medium absorption, we establish the heat conduction model to describe the temperature distribution in diode-pumped alkali vapor lasers (DPALs) with two different pumping ways. Combining with the experimental parameters in cesium laser, the spatial temperature distribution picture, the longitudinal and the radial temperature distributions of two cesium lasers

  15. Influence of light polarization on the dynamics of optically pumped lasers

    Microsoft Academic Search

    M. Arjona; R. Corbalan; F. Laguarta; J. Pujol; R. Vilaseca

    1990-01-01

    The dynamic behavior of a coherently pumped ring laser with a homogeneously broadened four-level medium is analyzed theoretically, considering linearly polarized pump and generated laser beams. The laser is shown to be much more stable when these polarizations are parallel than when they are orthogonal. In the latter case the instability pump threshold can be as low as four times

  16. Tunable IR Lasers for Helium Optical Pumping

    Microsoft Academic Search

    Padetha Tin

    1990-01-01

    It has been clear for a number of years that the efficiency of the optical pumping process in helium gas could be improved substantially if a tunable, intense source of radiation were available at the resonance wavelength of the helium triplet metastable atom, 1083 nm. Until recently such sources were unavailable. It was the purpose of this research to develop

  17. 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.

  18. Diode- and flashlamp-pumped solid state Raman lasers

    NASA Astrophysics Data System (ADS)

    Cerny, Pavel; Jelinkova, Helena; Jabczynski, Jan K.; Zendzian, Waldemar; Sulc, Jan

    2003-11-01

    We report on the development of passively Q-switched Nd:YAG and Nd:YAP lasers with solid-state stimulated Raman scattering (SRS) frequency conversion to 1.2-?m. A new barium tungstate (BaWO4) crystal was investigated as nonlinear converter. Diode pumped Nd:YAG quasi-continuous-wave slab laser, operated at 14-Hz repetition rate, was passively Q-switched by a Cr4+:YAG crystal. A three-mirror linear laser cavity with BaWO4 crystal produced the maximal Raman-shifted output pulse energy of 2.3 mJ. The first Stokes output energy was 1.5 mJ corresponding to 0.4 MW peak power. The SRS conversion efficiency with respect to laser operation at the fundamental wavelength was estimated to 55%. Flashlamp-pumped Nd:YAP laser was passively Q-switched by a BDN II thin film and the repetition rate was 2 Hz. The maximal first Stokes output energy was 12 mJ and the pulse peak power was 1.7 MW. Solid state Raman laser technology can therefore be employed to reach new laser output wavelengths using simple, reliable, and compact arrangements with a use of well-developed Nd-doped host lasers.

  19. Direct laser interference patterning of polystyrene films doped with azo dyes, using 355 nm laser light

    NASA Astrophysics Data System (ADS)

    Broglia, M. F.; Suarez, S.; Soldera, F.; Mücklich, F.; Barbero, C. A.; Bellingeri, R.; Alustiza, F.; Acevedo, D.

    2014-05-01

    The generation of line-like periodic patterns by direct laser interference patterning (DLIP) of polystyrene films (PS) at a wavelength of 355 nm has been investigated. No structuration is achieved in plain PS due to the weak absorption of the polymer at 355 nm. On the other hand, patterning is achieved on films doped (PSd) with an azo dye (2-anisidine ? 2-anisidine) which is incorporated in the polymer solution used for film preparation. Periodic micro-structures are generated. DLIP on PSd results in the swelling of the surface at low fluences, while at high laser intensities it causes the ablation of the regions at the interference maxima positions. The results contrast with the usual process of DLIP on PS (at shorter wavelengths, like 266 nm) where only ablation is detected. The results suggest that decomposition of the azo dye is the driving force of the patterning which therefore differ from the patterning obtained when plain PS is irradiated with laser light able to be absorbed by the aromatic ring in PS (e.g. 266 nm). The biocompatibility of these materials and adhesion of cells was tested, the data from in vitro assays shows that fibroblast cells are attached and proliferate extensively on the PSd films.

  20. 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.

  1. CW-pumped polarization-maintaining Brillouin fiber ring laser

    E-print Network

    Boyer, Edmond

    CW-pumped polarization-maintaining Brillouin fiber ring laser: II. Active mode-locking by phase polarization- maintaining fiber ring cavity excites spontaneous stable mode-locking. But the shortest pulses a phase modulator inside the ring. The experiment is carried out in the infrared at 1.319 µm

  2. An optically-pumped silicon evanescent microring resonator laser

    Microsoft Academic Search

    Di Liang; M. Florentino; Alexander W. Fang; Daoxin Dai; Ying-Hao Kuo; Raymond G. Beausoleil; John E. Bowers

    2009-01-01

    We demonstrate an optically-pumped hybrid silicon evanescent microring laser fabricated by a self-aligned process. Low threshold carrier densities (<2.5times1018 cm-3) are measured for both 15 and 25 mum diameter devices. Lasing up to 50degC is achieved with 0.1 nm\\/degC wavelength red shift rate.

  3. The Dynamics and Coherent Properties of Electron - Pumped Semiconductor Lasers

    Microsoft Academic Search

    Jacob Khurgin

    1987-01-01

    In this work the dynamics and coherence properties of electron beam pumped visible semiconductor lasers have been studied over a wide range of operating conditions. Experiments were conducted on a specially designed and built demountable cathode-ray tube (CRT) system, enabling quick processing of samples, efficient excitation and simultaneous acquisition of optical and electrical data. The problem of achieving adequate e-beam

  4. Phase dynamics in a Doppler broadened optically-pumped laser

    Microsoft Academic Search

    E. Roldán; G. J. de Valcárcel; R. Vilaseca; F. Silva; J. Pujol; R. Corbalán; F. Laguarta

    1989-01-01

    The dynamic behavior of the phase of the generated field in a Doppler-broadened optically-pumped far-infrared laser is theoretically investigated for the first time. The phase undergoes sudden jumps of approximately pi radians, which allow to establish the actual symmetry of the main attractor in the phase space, explaining the heteroclynic character of the chaotic behavior observed in experiments.

  5. Development of distributed feedback dye lasers for generation of high-power 193 nm excimer laser short pulses

    Microsoft Academic Search

    Yifeng Cui

    1993-01-01

    The combination of picosecond dye lasers, nonlinear mixing in crystals, and excimer amplifiers offers an attractive way to generate intense diffraction-limited pulses throughout the ultraviolet region. However, it is difficult to generate 193 nm seed pulses because this wavelength cannot be obtained by second harmonic generation method in any known crystals. The thesis will describe a laser system which efficiently

  6. QUANTITATIVE DETECTION OF ENVIRONMENTALLY IMPORTANT DYES USING DIODE LASER/FIBER-OPTIC RAMAN

    EPA Science Inventory

    A compact diode laser/fiber-optic Raman spectrometer is used for quantitative detection of environmentally important dyes. This system is based on diode laser excitation at 782 mm, fiber optic probe technology, an imaging spectrometer, and state-of-the-art scientific CCD camera. ...

  7. Optofluidic ring resonator based dye laser Siyka I. Shopova, Hongying Zhou, and Xudong Fana

    E-print Network

    Fan, Xudong "Sherman"

    interest in microfluidic dye lasers that incorporate optical feedbacks with microfab- ricated fluidic incompatible with plastic tubings and connectors that are a part of fluidics. Alternatively, a solid optical in the core to support the low-threshold laser oscillation. Additionally, the WGM has the evanescent field

  8. Collagen Remodeling After 585-nm Pulsed Dye Laser Irradiation: An Ultrasonographic Analysis

    E-print Network

    McCarthy, John E.

    Collagen Remodeling After 585-nm Pulsed Dye Laser Irradiation: An Ultrasonographic Analysis BRENT R interest among both laser surgeons and patients. Evidence indicates that dermal collagen formation is the key mechanism of action for the nonablative techniques. We studied, with ultrasound, new collagen

  9. Yellow dye laser thermotherapy of choroidal neovascularisation in age related macular degeneration

    Microsoft Academic Search

    Margo R Beintema; Jendo A Oosterhuis; Fred Hendrikse

    2001-01-01

    AIMA pilot study of the feasibility of using dye laser thermotherapy (LTT) at a subcoagulation temperature to occlude newly formed vessels in patients with age related macular degeneration (AMD).METHODSChoroidal neovascularisation (CNV) in 24 eyes with exudative AMD was treated with a continuous wave yellow laser at 578 nm. Parameters were an exposure time of 2 or 5 seconds, a spot

  10. Femtosecond Cr:Colquiriite Lasers Pumped by a Single Tapered Diode Laser

    E-print Network

    Demirbas, Umit

    Ti:Sapphire lasers could provide tunable femtosecond pulses in the 680-1180 nm region; however, due to the requirement of expensive green pump sources, its current cost sets a barrier to its widespread adoption. As an ...

  11. Highly efficient passive Q switches for a neodymium laser based on thiopyrylotricarbocyanine dyes

    SciTech Connect

    Bezrodnyi, V I [Institute of Physics, National Academy of Sciences of Ukraine, Kiev (Ukraine); Derevyanko, Nadezhda A; Ishchenko, Aleksandr A; Kropachev, A V [Institute of Organic Chemistry, National Academy of Sciences of Ukraine, Kiev (Ukraine)

    2009-01-31

    The spectral, photochemical and nonlinear optical properties of a group of thiopyrylotricarbocyanine dyes in a polyurethane matrix are studied and compared with well-known materials for passive Q-switching such as nickel BDN and BDNII complexes. Passive laser Q switches based on these dyes feature the high modulation efficiency (up to 76%) in neodymium lasers and high photochemical stability. It is shown that the service life of Q switches can be considerably increased by removing oxygen from a polymer matrix. (elements of laser setups)

  12. 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.

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

    NASA Astrophysics Data System (ADS)

    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 B-10 and He-3, 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 percent. 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 percent) 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 C3F7I, 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.

  14. Chemical pumping of pure rotational HF lasers

    Microsoft Academic Search

    John H. Smith; Dean W. Robinson

    1981-01-01

    Pure rotational laser oscillation has been observed in HF following flash photolysis of various mixtures of trifluoromethyl halide, acetylenic compound, and argon in the ration of 1:1:100. Specifically, mixtures of CF3I+C2H2, CF3I+CH3C2H, and CF3Br+C2H2 exhibit different patterns of laser intensity, and, further, are markedly different from patterns generated by the known photoelimination system CH2CF2. The above systems show laser intensity

  15. 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.

  16. Photophysical and photochemical properties of coumarin laser dyes in amphiphilic media. Technical report, 1 Jan-31 Oct 83

    SciTech Connect

    Jones, G. II; Jackson, W.R.; Kanoktanaporn, S.; Bergmark, W.R.

    1983-10-31

    Photophysical properties of coumarin laser dyes solubilized in aqueous detergent or cyclodextrin solutions have been investigated. Dyes appear to be incorporated in hydrated (hydrogen bonded) sites within detergent micelles. Photodegradation is inhibited for detergent solubilized dye. Electron transfer photochemistry is examined by flash photolysis.

  17. Femtosecond Cr{sup 4+}:forsterite laser pumped by ytterbium-doped fibre laser and its noise characteristics

    SciTech Connect

    Gordienko, Vyacheslav M; Konovalov, Aleksei N; Podshivalov, Alexey A; Pryalkin, Vladimir I; Savel'ev, Andrei B [Department of Physics, M.V. Lomonosov Moscow State University, Moscow (Russian Federation); Ivanov, Andrei A [Photochemistry Center, Russian Academy of Sciences, Moscow (Russian Federation)

    2002-06-30

    A femtosecond Cr{sup 4+}:forsterite laser is fabricated which is pumped by a PYL-10-LP fibre laser and generates a continuous train of 45-fs pulses with a repetition rate of 110 MHz and an average output power of 250 mW. The noise spectra of the femtosecond and solid-state pump lasers are studied. (lasers)

  18. 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 [Russian Federal Nuclear Center - The All-Russian Research Institute of Experimental Physics, Sarov, Nizhnii Novgorod region (Russian Federation); Efanov, V M; Efanov, M V; Yarin, P M ['FID Technology' Research and Production Association, St.Petersburg (Russian Federation); Kazantsev, S Yu; Kononov, I G; Firsov, K N [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); 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)

  19. Simple 1 micron ring laser oscillators pumped by fiber-coupled laser diodes

    Microsoft Academic Search

    Anthony J. Alfrey

    1994-01-01

    We have designed simple nonplanar Nd:YAG ring laser oscillators that utilize all flat mirrors and are pumped by the fiber-coupled output from ten 3 watt diode lasers. We have obtained up to 8.5 W at 1.06 microns of diffraction-limited, single frequency output with no measureable astigmatism or ellipticity with a total pump power of 26 W from a pair of

  20. Optimization in scaling fiber-coupled laser-diode end-pumped lasers to higher power: influence of thermal effect

    Microsoft Academic Search

    Y. F. Chen; T. M. Huang; C. F. Kao; C. L. Wang; S. C. Wang

    1997-01-01

    The optimum mode-to-pump ratio in scaling fiber-coupled laser-diode end-pumped lasers to higher power has been investigated by including the thermal effect into the space-dependent rate equation analysis. The optical path difference (OPD) distribution has been derived as a function of the pump-beam quality, focus position of pumping light, and pump radius at the focal plane under the assumption that the

  1. Negative-coupling resonances in pump-coupled lasers

    E-print Network

    T. W. Carr; M. L. Taylor; I. B. Schwartz

    2005-10-28

    We consider coupled lasers, where the intensity deviations from the steady state, modulate the pump of the other lasers. Most of our results are for two lasers where the coupling constants are of opposite sign. This leads to a Hopf bifurcation to periodic output for weak coupling. As the magnitude of the coupling constants is increased (negatively) we observe novel amplitude effects such as a weak coupling resonance peak and, strong coupling subharmonic resonances and chaos. In the weak coupling regime the output is predicted by a set of slow evolution amplitude equations. Pulsating solutions in the strong coupling limit are described by discrete map derived from the original model.

  2. Ho:KLuW microchip laser intracavity pumped by a diode-pumped Tm:KLuW laser

    NASA Astrophysics Data System (ADS)

    Serres, J. M.; Loiko, P. A.; Mateos, X.; Yumashev, K. V.; Kuleshov, N. V.; Petrov, V.; Griebner, U.; Aguiló, M.; Díaz, F.

    2015-07-01

    A compact intracavity-pumped microchip Ho laser is realized using stacked Tm:KLuW/Ho:KLuW crystals pumped by a laser diode at 805 nm; both crystals are cut for light propagation along the N g optical indicatrix axis and emit with polarization along the N m axis. Maximum CW output power of 285 mW is achieved at a wavelength of 2080 nm for 5.6 W absorbed pump power in the Tm:KLuW crystal with a maximum slope efficiency of 8.3 %. Maximum total (Tm3+ and Ho3+ emission) output of 887 mW with a slope efficiency of 23 % is achieved. Laser operation is obtained in the 1867-1900 nm spectral range corresponding to the Tm emission, while Ho emits at 2078-2100 nm, depending on the output coupling. The microchip Ho laser generates a near-circular output beam with M 2 < 1.1. The compact laser setup with plane-plane cavity provides automatic mode-matching condition for the Tm and Ho laser modes.

  3. Chemical pumping of pure rotational HF lasers

    Microsoft Academic Search

    J. H. Smith; D. W. Robinson

    1981-01-01

    In the reported investigation, pure rotational laser oscillation has been observed in HF, following flash photolysis of various mixtures of trifluoromethyl halide, acetylenic compound, and argon in the ratio of 1:1:100. Specifically, mixtures of CF3I + C2H2, CF3I + CH3C2H, and CF3Br + C2H2 exhibit different patterns of laser intensity, and, further, are markedly different from patterns generated by the

  4. High-power diode laser bars as pump sources for fiber lasers and amplifiers (Invited Paper)

    NASA Astrophysics Data System (ADS)

    Bonati, G.; Hennig, P.; Wolff, D.; Voelckel, H.; Gabler, T.; Krause, U.; T'nnermann, A.; Reich, M.; Limpert, J.; Werner, E.; Liem, A.

    2005-04-01

    Fiber lasers are pumped by fibercoupled, multimode single chip devices at 915nm. That"s what everybody assumes when asked for the type of fiber laser pumps and it was like this for many years. Coming up as an amplifier for telecom applications, the amount of pump power needed was in the range of several watts. Highest pump powers for a limited market entered the ten watts range. This is a range of power that can be covered by highly reliable multimode chips, that have to survive up to 25 years, e.g. in submarine applications. With fiber lasers entering the power range and the application fields of rod and thin disc lasers, the amount of pump power needed raised into the area of several hundred watts. In this area of pump power, usually bar based pumps are used. This is due to the much higher cost pressure of the industrial customers compared to telecom customers. We expect more then 70% of all industrial systems to be pumped by diode laser bars. Predictions that bar based pumps survive for just a thousand hours in cw-operation and fractions of this if pulsed are wrong. Bar based pumps have to perform on full power for 10.000h on Micro channel heat sinks and 20.000h on passive heatsinks in industrial applications, and they do. We will show a variety of data, "real" long time tests and statistics from the JENOPTIK Laserdiode as well as data of thousands of bars in the field, showing that bar based pumps are not just well suitable for industrial applications on high power levels, but even showing benefits compared to chip based pumps. And it"s reasonable, that the same objectives of cost effectiveness, power and lifetime apply as well to thin disc, rod and slab lasers as to fiber lasers. Due to the pumping of fiber lasers, examples will be shown, how to utilize bars for high brightness fiber coupling. In this area, the automation is on its way to reduce the costs on the fibercoupling, similar to what had been done in the single chip business. All these efforts are part of the JENOPTIK Laserdiode"s LongLifeTechnologie.

  5. 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.

  6. 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.

  7. Development of a frequency doubled high powered laser diode end-pumped Nd:YVO?/LBO laser 

    E-print Network

    Barr, Aaron Maxwell

    2003-01-01

    to determine the temperature distribution within the laser media. Experiments are performed to characterize the laser diode spectral output and laser crystal response to the pump radiation. Finally, the thesis presents a simple technique to image infrared...

  8. Transient collisionally excited X-ray laser in nickel-like zirconium pumped with the PHELIX laser facility

    NASA Astrophysics Data System (ADS)

    Neumayer, P.; Seelig, W.; Cassou, K.; Klisnick, A.; Ros, D.; Ursescu, D.; Kuehl, T.; Borneis, S.; Gaul, E.; Geithner, W.; Haefner, C.; Wiewior, P.

    A transient collisionally excited X-ray laser has been put into operation using the front end of the PHELIX laser system as a pump laser. Strong lasing at 22 nm has been observed in nickel-like zirconium.

  9. Powerful 2-?m 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 ?m, 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 ?m, which also can be further improved by optimizing the parameters of the sources.

  10. 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 the shortest wavelength laboratory x-ray laser, below 4.5 nm and operating in the water window, by using the high-energy capability of the Titan laser.

  11. Performances of Ho:YAG laser intracavity-pumped by a diode-pumped Tm:YLF laser

    NASA Astrophysics Data System (ADS)

    Kieleck, Christelle; Hirth, Antoine; Schellhorn, Martin

    2004-04-01

    Q-switched and diode-pumped 2 ?m solid state lasers are becoming of increasing interest for efficient pumping of mid-infrared emitting optical parametric oscillators (OPOs). In particular, Thulium and Holmium rare earths seem to be most suited for systems with high efficiency due to their long upper state lifetime. Several works on Ho:YAG laser end-pumped by diode-pumped Tm:YLF laser have demonstrated high power operations. To simplify the set-ups, experiments with Tm-Ho intracavity lasers have been done; they demonstrated a 36.5% slope efficiency. Unfortunately these set-ups did now allow Q-switched operations and the thermal lens in the rods led to relatively poor beam quality (M2 ~ 5-6). We design an original intracavity configuration with a dichroic polarizing beamsplitter to decouple Tm:YLF and Ho:YAG cavities. This solution improves the beam quality and allows Q-switched operations. We obtained 1.9 W of 2.09 ?m at the 17.3 W diodes pump level. The slope efficiency of the diode-pump to the Ho laser output and the optical-to-optical conversion efficiency achieved are respectively ~ 21.4% and ~ 11%. As anticipated, we experimentally scaled a shift of Tm:YLF emission from 1.908 to 1.953 ?m that leads to an efficiency decrease for the Tm laser. In this intracavity geometry, Ho:YAG acted as a saturable absorber. Instead of a cw operation in free running, we observed random Tm:YLF laser pulses of ~ 2.5 ?s that each resulted in a Ho pulse (~ 200-250 ns). When the acousto-optic modulator (AOM) worked, the Ho pulses did not follow the Q-switched frequency. In fact Ho emission depends on the Tm:YLF pump energy accumulated between two gates of the AOM. Possible ways to optimize the efficiency and avoid the passive Q-switching behaviour of Ho:YAG are suggested.

  12. Automatic design scheme for optical-fiber Raman amplifiers backward-pumped with multiple laser diode pumps

    Microsoft Academic Search

    Minhui Yan; Jianping Chen; Wenning Jiang; Jianlang Li; Junfeng Chen; Xin Li

    2001-01-01

    A simulated annealing algorithm is adopted to give an automatic pump configuration in laser-diode backward-pumped-distributed fiber Raman amplifiers. The demonstration of the optimization process of wavelengths and powers in an optical-fiber Raman amplifier using four laser-diode pumps is presented. The resulting gain ripple is less than 2.6 dB in respect to the 30 dB average gain in the amplification bandwidth

  13. New ytterbium-phosphate glass for diode-pumped lasers

    SciTech Connect

    Galagan, B I; Glushchenko, I N; Denker, B I; Sverchkov, S E [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Kisel', V E; Kuril'chik, S V; Kuleshov, N V [International Laser Center, Belarus State Technical University, Minsk (Belarus)

    2009-10-31

    A new ytterbium laser glass based on an alumoborophosphate composition is developed. It is shown that the chemical and thermal stabilities of this glass are record-high for phosphate glasses and that its spectral and luminescent characteristics compare well with popular laser glasses. A mould of laser-quality glass doped with ytterbium with a concentration of 5x10{sup 20} cm{sup -3} is synthesised. Active laser elements 5x5x2 mm in size are prepared from this glass for longitudinal diode pumping. These elements were used to fabricate a laser, whose output power in the cw regime reached 783 mW and maximum slope efficiency was 28.9%. Pulses with a duration of {approx}150 fs and a peak power of about 5 kW are obtained in the passive mode-locking regime. (active media)

  14. Photoinduced processes in solid polymer solutions of dyes in an interference field of laser radiation

    SciTech Connect

    Sizykh, A G; Tarakanova, E A [Quantum Electronics Division, Krasnoyarsk State University, Krasnoyarsk (Russian Federation)

    1998-12-31

    An investigation was made of the relationships governing the photochemical mechanism of formation of light-induced gratings in solid polymer solutions of a dye with a high quantum yield of the triplet states. The combined analysis of the results of real and numerical experiments was made for a solution of eosin K in gelatin. The protonation rate constant of the dye was measured and the dependence of the diffraction efficiency on the duration of irradiation was explained taking diffusion of the dye into account. A method was proposed for determination of the duffusion coefficient in a spatially modified interference field of the laser radiation. The diffusion coefficients were found. (nonlinear optical phenomena)

  15. LED side-pumped Nd3+:YVO4 laser at room temperature

    NASA Astrophysics Data System (ADS)

    Barbet, Adrien; Grardel, Hugo; Paul, Amandine; Blanchot, Jean-Philippe; Balembois, François; Druon, Frédéric; Georges, Patrick

    2015-02-01

    The lighting market has recently improved LED performance by orders of magnitudes. In parallel, massive production decreases dramatically LED price. Those improvements triggered new interests for LED pumping of lasers which was first studied in the early 1980s on neodymium doped and ytterbium doped lasers at low temperature. Since the 2000's, several research teams started to revisit the concept of LED pumped lasers: polymer laser, fiber laser and semiconductors have recently demonstrated laser effect under visible LED pumping. However, no experimental results were reported on LED pumped bulk crystals. In this paper, we demonstrated for the first time a LED pumped Nd:YVO4 laser operating at room temperature. We investigated two pumping wavelengths: in the amber around 600 nm and in the near infrared around 850 nm. The laser operated in quasi-cw-pumping regime to increase the LED intensity. We performed a two-mirror cavity transversely pumped by 36 LEDs. Laser operation was achieved at room temperature for the both pump wavelengths: a maximum output energy of 40?J for an emitted energy of 7.4 mJ with infrared pumping and an energy of 11.7 ?J for an emitted energy or 2.3 mJ with amber pumping. This works demonstrated that LED pumping has an interesting potential to realize ultra low cost solid state lasers operating in pulsed regime at kHz repetition rate and with energies in the mJ range.

  16. Measurement of liquid sheet using laser tagging method by photochromic dye

    NASA Astrophysics Data System (ADS)

    Rosli, Nurrina Binti; Amagai, Kenji

    2014-12-01

    Liquid atomization system has been extensively applied as the most significant process in many industrial fields. In the internal combustion engine, the combustion phenomenon is strongly influenced by the spray characteristics of the fuel given by the atomization process. In order to completely understand the whole atomization process, a detail investigation of relations between the liquid jet characteristics and the breakup phenomenon is required. In this study, a non-intrusive method called as laser tagging method by photochromic dye has been developed with aim to study the breakup process of liquid sheet in detail, covering from the behavior in film until disintegrated into ligament and droplets. The laser tagging method by photochromic dye is based on a shift in the absorption spectrum of photochromic dye molecules tagged by ultraviolet laser. The shift results a color change at the tagged region of liquid containing the dye. In this study, the motions of the dye traces were analyzed as the liquid surface velocity. As a result, liquid sheet was found to keep its velocity constantly in film before suddenly increase around broken point. However, it then decreased after broken into droplets. By forming a set of four points of dye traces on the liquid sheet, the change of relative position of the set enabled the measurement of deformation and rotational motion of the liquid sheet. As a result, the normal strain of the liquid sheet parallel to the flow direction depended on the flow behavior of ligament formation.

  17. New class of cw high-power diode-pumped alkali lasers (DPALs) (Plenary Paper)

    Microsoft Academic Search

    William F. Krupke; Raymond J. Beach; Vernon K. Kanz; Stephen A. Payne; James T. Early

    2004-01-01

    The new class of diode-pumped alkali vapor lasers (DPALs) offers high efficiency cw laser radiation at near-infrared wavelengths: cesium 895 nm, rubidium 795 nm, and potassium 770 nm. The working physical principles of DPALs will be presented. Initial 795 nm Rb and 895 nm Cs laser experiments performed using a titanium sapphire laser as a surrogate pump source demonstrated DPAL

  18. New Class of CW High-Power Diode-Pumped Alkali Lasers (DPALs)

    Microsoft Academic Search

    W F Krupke; R J Beach; V K Kanz; S A Payne; J T Early

    2004-01-01

    The new class of diode-pumped alkali vapor lasers (DPALs) offers high efficiency cw laser radiation at near-infrared wavelengths: cesium 895 nm, rubidium 795 nm, and potassium 770 nm. The working physical principles of DPALs will be presented. Initial 795 nm Rb and 895 nm Cs laser experiments performed using a titanium sapphire laser as a surrogate pump source demonstrated DPAL

  19. Environmental testing of a diode-laser-pumped Nd:YAG laser and a set of diode-laser-arrays

    NASA Astrophysics Data System (ADS)

    Hemmati, H.; Lesh, J. R.

    1989-06-01

    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.

  20. Dual-pump CARS temperature and major species concentration measurements in counter-flow methane flames using narrowband pump and broadband Stokes lasers

    SciTech Connect

    Thariyan, Mathew P.; Ananthanarayanan, Vijaykumar; Bhuiyan, Aizaz H.; Naik, Sameer V.; Gore, Jay P.; Lucht, Robert P. [School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907 (United States)

    2010-07-15

    Dual-pump coherent anti-Stokes Raman scattering (CARS) is used to measure temperature and species profiles in representative non-premixed and partially-premixed CH{sub 4}/O{sub 2}/N{sub 2} flames. A new laser system has been developed to generate a tunable single-frequency beam for the second pump beam in the dual-pump N{sub 2}-CO{sub 2} CARS process. The second harmonic output ({proportional_to}532 nm) from an injection-seeded Nd:YAG laser is used as one of the narrowband pump beams. The second single-longitudinal-mode pump beam centered near 561 nm is generated using an injection-seeded optical parametric oscillator, consisting of two non-linear {beta}-BBO crystals, pumped using the third harmonic output ({proportional_to}355 nm) of the same Nd:YAG laser. A broadband dye laser (BBDL), pumped using the second harmonic output of an unseeded Nd:YAG laser, is employed to produce the Stokes beam centered near 607 nm with full-width-at-half-maximum of {proportional_to}250 cm{sup -1}. The three beams are focused between two opposing nozzles of a counter-flow burner facility to measure temperature and major species concentrations in a variety of CH{sub 4}/O{sub 2}/N{sub 2} non-premixed and partially-premixed flames stabilized at a global strain rate of 20 s{sup -1} at atmospheric-pressure. For the non-premixed flames, excellent agreement is observed between the measured profiles of temperature and CO{sub 2}/N{sub 2} concentration ratios with those calculated using an opposed-flow flame code with detailed chemistry and molecular transport submodels. For partially-premixed flames, with the rich side premixing level beyond the stable premixed flame limit, the calculations overestimate the distance between the premixed and the non-premixed flamefronts. Consequently, the calculated temperatures near the rich, premixed flame are higher than those measured. Accurate prediction of the distance between the premixed and the non-premixed flames provides an interesting challenge for future computations. (author)

  1. Carbon dioxide gas laser with nuclear pumping

    Microsoft Academic Search

    A. A. Pustovalov; B. M. Smirnov

    1975-01-01

    Calculation of the parameters of a laser consisting of a tube filled with a mixture of helium, nitrogen, and CO2, and excited by a radioactive material covering the walls of the tube. Vibrational excitation of the molecules, raising them to the upper lasing level, takes place via secondary electrons created by ionization of the gas molecules by nuclear particles. The

  2. Laser-diode-pumped Nd:YAG active-mirror laser

    SciTech Connect

    Kasamatsu, T.; Sekita, H. [Opto-Electronics Research Laboratories, NEC Corporation, 4-1-1 Miyazaki, Miyamae-ku, Kawasaki, Kanagawa 216 (Japan)

    1997-03-01

    We describe a simple design, loaser-diode-pumped cw Nd:YAG active-mirror laser and present a thermal analysis of the crystal. A cw output power of 2.4 W and an M{sup 2} beam quality value of less than 1.9 at an incident pumping power of 8.9 W were obtained. From the thermal analysis we predict that the output power can be increased by increasing the pump beam diameter and the pump power at a constant excitation density. {copyright} 1997 Optical Society of America

  3. 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.

  4. 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.

  5. 2.7mW output of emerald laser pumped by laser diode

    Microsoft Academic Search

    Z. Q. Chen; G. Zhang

    2005-01-01

    Free-running emerald laser pumped by 660 nm LD was reported. 2.7mW of CW output power has been obtained with overall efficiency of 1% and slope efficiency of 1.33% when the LD incident power was 2.56 W. The laser threshold value of emerald crystal was estimated 0.5W.

  6. 2.7mW output of emerald laser pumped by laser diode

    NASA Astrophysics Data System (ADS)

    Chen, Z. Q.; Zhang, G.

    2005-12-01

    Free-running emerald laser pumped by 660 nm LD was reported. 2.7mW of CW output power has been obtained with overall efficiency of 1% and slope efficiency of 1.33% when the LD incident power was 2.56 W. The laser threshold value of emerald crystal was estimated 0.5W.

  7. Efficient, frequency-stable laser-diode-pumped Nd:YAG laser

    Microsoft Academic Search

    Bingkun Zhou; Thomas J. Kane; George J. Dixon; Robert L. Byer

    1985-01-01

    We have designed and tested a laser-diode-pumped monolithic Nd:YAG oscillator. The electrical-to-optical slope efficiency was 6.5%. The frequency jitter was less than 10 kHz over a 0.3-sec period, the best frequency stability reported for a Nd:YAG laser to date.

  8. Spatially tunable laser emission in dye-doped photonic liquid crystals Yuhua Huang, Ying Zhou, and Shin-Tson Wua

    E-print Network

    Wu, Shin-Tson

    laser emission of the dye-doped cholesteric liquid crystal CLC cell using a one-dimensional temperatureSpatially tunable laser emission in dye-doped photonic liquid crystals Yuhua Huang, Ying Zhou a periodic modulation of the refractive index. Conse- quently, a one-dimensional photonic band gap PBG is es

  9. Low-cost, single-mode diode-pumped Cr:Colquiriite lasers

    E-print Network

    Demirbas, Umit

    We present three Cr[superscript 3+]:Colquiriite lasers as low-cost alternatives to Ti:Sapphire laser technology. Single-mode laser diodes, which cost only $150 each, were used as pump sources. In cw operation, with ~520 ...

  10. 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.

  11. 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.

  12. 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.

  13. Electron Beam Pumped Tunable Excimer Lasers

    Microsoft Academic Search

    Michael C. Smayling

    1981-01-01

    Laser characteristics were studied extensively for the broadband rare gas halide excimers Xe(,2)Cl, Kr(,2)F, and XeF (C(--->)A). The trimer Kr(,2)F was first observed to lase during these investigations, while Xe(,2)Cl and XeF (C(--->)A) had been previously demonstrated. Since all three excimers have unbound ground states, a spectrally wide emission bandwidth is available for wavelength tuning. Other excimers with wide band

  14. 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.

  15. Efficient laser-diode end-pumped Nd:GGG lasers at 1054 and 1067 nm.

    PubMed

    Xu, Bin; Xu, Huiying; Cai, Zhiping; Camy, P; Doualan, J L; Moncorgé, R

    2014-10-10

    Efficient and compact laser-diode end-pumped Nd:GGG simultaneous multiwavelength continuous-wave lasers at ?1059, ?1060 and ?1062??nm were first demonstrated in a free-running 30 mm plano-concave laser cavity. The maximum output power was up to 3.92 W with a slope efficiency of about 53.6% with respect to the absorbed pump power. By inserting a 0.1 mm optical glass plate acting as a Fabry-Pérot etalon, a single-wavelength laser at ?1067??nm with a maximum output power of 1.95 W and a slope efficiency of 28.5% can be obtained. Multiwavelength lasers, including those at ?1054 or ?1067??nm, were also achievable by suitably tilting the glass etalon. These simultaneous multiwavelength lasers provide a potential source for terahertz wave generation. PMID:25322387

  16. Self-curable solid-state elastic dye lasers capable of mechanical stress probing.

    PubMed

    Yang, Yu; Liao, Zhifu; Zhou, Yuan; Cui, Yuanjing; Qian, Guodong

    2013-05-15

    Herein, a highly sensitive stress probe is reported based on pyrromethene 597 (PM597) doped elastic polydimethylsiloxane films. By sandwiching the dye doped elastic film with two plano dichromatic mirrors, a solid-sate microcavity laser with low laser threshold (~0.2 ?J) is presented as a straightforward probing method for mechanical stress, which is monitored by the laser output spectra, demonstrating a resolution limit higher than 0.01 MPa. The photostability of PM597 doped into the microcavity laser is higher than 7222 GJ/mol, which is among the highest record ever reported to our knowledge and a fast self-recovery on the laser output in less than 1 h, attributed to diffusion of dye molecules is observed, indicating a practical durability for such stress probes. PMID:23938891

  17. Dynamics of solid-state lasers pumped by mode-locked lasers.

    PubMed

    Wellmann, Barbara; Spence, David J; Coutts, David W

    2015-02-23

    We analyze the dynamics of mode-locked pumped solid-state lasers focusing on the transition between mode-locked and CW behavior. Where the ratio of the pump and laser cavity lengths is a rational number, 'rational-harmonic mode-locking' is obtained. When the cavity length is detuned away from such resonances, modulated continuous output is generated. The transition from mode-locked to modulated CW operation is explored experimentally for a Ce:LiCAF laser operating at 290 nm and pumped by a 78.75 MHz mode-locked frequency quadrupled Nd:YVO4 laser. Both CW output and mode-locked output with pulse repetition rates up to 1.1 GHz were achieved. A rate equation model is developed to predict optimum cavity lengths for achieving CW output with minimized modulation. PMID:25836481

  18. Scaling CW diode-end-pumped Nd:YAG lasers to high average powers

    Microsoft Academic Search

    Steve C. Tidwell; Jonathan F. Seamans; Mark S. Bowers; Ananda K. Cousins

    1992-01-01

    The authors analyze the scaling limits of diode-end-pumped Nd:YAG lasers imposed by pumping geometry, thermal distortion, birefringence, and fracture. A scalable 15-W output power diode-end-pumped laser which achieves a 60% slope efficiency is demonstrated. Thermal distortion in this laser is reduced from 2.6 waves to less than 0.15 waves with an aspheric laser rod. Depolarization is reduced by 40 times

  19. Laser cooling of doped crystals by methods of coherent pumping

    NASA Astrophysics Data System (ADS)

    Ivanov, Andrei V.; Rozhdestvensky, Yurii V.

    2015-03-01

    Methods of coherent pumping through dipole-allowed 5d levels of RE ion are proposed for laser cooling. The coherent and complete population transfer between the ground and the first excited levels of 4f multiplet is achieved by using the different Raman techniques, namely two-photon scattering, adiabatic passage method, and ?-pulse pumping. It is shown that the multiplication of the number of electrons that participate in cooling cycle leads to increasing of the cooling power and to acceleration of the cooling process. The increasing of cooling efficiency of 0.5% compared to the direct pumping between 4f levels is attained through the use of dipole-allowed optical transitions. Performed estimates show that the sample temperature can achieve 94 K for current purity materials. The calculations are obtained for Yb3+:CaF2 system.

  20. High-power compact laser with segmented longitudinal pumping of coupled laser channels

    NASA Astrophysics Data System (ADS)

    Mamonov, D. N.; Il'ichev, N. N.; Sirotkin, A. A.; Pivovarov, P. A.; Rebrov, S. G.; Derzhavin, S. I.; Klimentov, S. M.

    2015-06-01

    The characteristics of a compact Nd:YAG/Cr:YAG laser with segmented end pumping using a bundle of seven optical fibres are presented. In the regime of optical coupling of thus formed seven laser channels, 3-ns pulses with an energy up to 20 mJ, as well as their trains, are obtained. The used method makes it possible to scale the energy and power of lasers of this type with controlled spatial beam profile.

  1. 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.

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

    SciTech Connect

    Behrens, E.G.; Jani, M.G.; Powell, R.C. (University Center for Laser Research, Oklahoma State Univ., Stillwater, OK (US)); Verdun, H.R. (Fibertek, Inc., Herndon, VA (US)); Pinto, A. (US Center for Night Vision and Electro-Optics, Fort Belvoir, VA (US))

    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. Kinetics of an optically pumped metastable Ar laser

    NASA Astrophysics Data System (ADS)

    Han, Jiande; Heaven, Michael C.; Hager, Gordon D.; Venus, George B.; Glebov, Leonid B.

    2014-03-01

    In recent studies, an optically pumped Ar*/He laser has been demonstrated using the Ar 4p[1/2]1?4s[3/2]2 transition at 912.55 nm. Time-resolved data for this system, recorded using CW laser excitation and pulsed discharge production of Ar* 4p[3/2]2, yielded laser output pulses that were of unexpectedly short duration. It was speculated that radiative relaxation from the upper laser level to the 4s[3/2]1 state (607 cm-1 above 4s[3/2]2) caused termination of the laser pulse. In the present study this hypothesis has been tested by observing the energy transfer kinetics of the 4s[3/2]2 and 4s[3/2]1 states in Ar/He gas mixtures. Following pulsed laser excitation out of 4s[3/2]2, population recovery was observed on a ?s time scale. Energy transfer from 4s[3/2]1 to 4s[3/2]2, induced by collisions with He, was characterized. The rate constant was found to be (1.0±0.5)x10-13 cm3 s-1. These observations confirmed that radiative transfer to 4s[3/2]1 was responsible for the short duration laser pulses. Modeling of a fully CW optically pumped Ar* laser shows that radiative transfer to 4s[3/2]1 reduces the number density of the Ar* atoms involved in lasing, but is otherwise benign.

  4. Demonstration of a compact 100 Hz, 0.1 J, diode-pumped picosecond laser

    E-print Network

    Rocca, Jorge J.

    Demonstration of a compact 100 Hz, 0.1 J, diode-pumped picosecond laser A. H. Curtis,1,2, * B. A demonstrated an all-diode-pumped Yb:YAG chirped pulse amplification laser that produces 100 mJ pulses of 5 ps that of other diode- pumped systems of comparable energy. © 2011 Optical Society of America OCIS codes: 140

  5. A compact electrically-pumped hybrid silicon microring laser

    Microsoft Academic Search

    Di Liang; Tadashi Okumura; Hsu-Hao Chang; Daryl Spencer; Ying-Hao Kuo; Alexander W. Fang; Daoxin Dai; Marco Fiorentino; Raymond G. Beausoleil; John E. Bowers

    2009-01-01

    A compact electrically-pumped hybrid silicon microring laser is realized on a hybrid silicon platform. A simplified, self-aligned, deep-etch process is developed to result in low-loss resonator with a high quality factor Q?15,000. Small footprint (resonator diameter=50 µm), electrical and optical losses all contribute to lasing threshold as low as 5.4 mA and up to 65 °C operation temperature in continuous-wave

  6. Electromagnetic wave pumped ion-channel free electron laser

    Microsoft Academic Search

    Liu Shenggang; R. J. Barker; Gao Hong; Yan Yang

    2001-01-01

    Theoretical study of electromagnetic wave pumped ion-channel free-electron laser (EPIC-FEL) is presented. The physical mechanism responsible for the generation of coherent radiation in the EPIC-FEL is described and the fundamental role of the ponderomotive wave in bunching and trapping the beam is emphasized. The dispersion relation of the EPIC-FEL has been obtained and growth rates are calculated for different parameters.

  7. XeF laser with optical pumping by surface discharges

    Microsoft Academic Search

    V S Zuev; G N Kashnikov; S B Mamaev

    1992-01-01

    We have investigated the spatial, temporal, and spectral characteristics of a XeF laser in the visible region (0.48 ?m) and the UV region (0.35 ?m). We have determined experimentally the dependence of the output energy on the vapor pressure of the original XeF2 gas for various configurations of the optical pumping source and various resonator Q factors. Output energies of

  8. Effects of pump laser chirp in high-order harmonics generated from various solid surfaces using femtosecond lasers

    Microsoft Academic Search

    C A Popovici; R A Ganeev; F Vidal; T Ozaki

    2012-01-01

    We investigate the effects of the pump laser chirp on high-order harmonic generation from solid surfaces of aluminium, indium and C60 film targets. Chirped pulses were produced by varying the distance between the two gratings of the laser compressor. We optimized the nanosecond contrast of our femtosecond laser pump (? = 35 fs, ? = 793 nm, I ? 1018

  9. Diode laser pumping sources for cryogenically cooled solid-state lasers

    NASA Astrophysics Data System (ADS)

    Maiorov, M. A.; Trofimov, I. E.

    2008-04-01

    One of the recent advances in solid-state laser (SSL) defense technology is the 100W level Er-doped "eye-safe" laser with low quantum defect pumping at 1.53?m. Major technical challenges in achieving high-wattage devices include increasing the system power conversion efficiency and arranging the removal of heat from both the crystal and the pumps. It is known that performance of the crystal can be improved dramatically by cryogenic cooling. Hence, it is desirable to have cryo-cooled pumps to realize ergonomic and efficient diode-pumped SSL with unified cryogenic cooling. In this paper we report on the development of LN2-cooled InP-based ?~1.5-1.6 ?m diode pumps. The broad area lasers demonstrated 11W in continuous-wave (CW) regime at an operating current of 20A. Despite the highest CW power measured to date from an InP-based emitter, we did not observe catastrophic optical mirror damage. The spectral width of the radiation from a cooled device decreased 1.5-2 from its room-temperature value, which will significantly improve pumping efficiency. We show that laser diode design has to be optimized for performance at cryogenic temperatures. Reviewing the data on LN2 cooled lasers emitting in the wavelength range of 1.13 - 1.8 ?m, we discuss the route to increase the power conversion of the LN2 cooled InP-based pumps to greater than 60% and further narrow and stabilize the laser emission spectrum.

  10. 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%.

  11. The energy transfer mechanism of a photoexcited and electroluminescent organic hybrid thin film of blue, green, and red laser dyes.

    PubMed

    Li, Weiling; Zhang, Jing; Zheng, Yanqiong; Chen, Guo; Cai, Miao; Wei, Bin

    2015-01-01

    Though optically pumped lasing has been realized for years, electrically pumped lasing has not yet been achieved in organic semiconductor devices. In order to make a better understanding of the laser mechanisms of the organic materials, we prepared organic thin films consisting of three efficient laser dyes of a blue emitter, 4?,4?'-N,N-diphenylamine-4,4'-diphenyl-1,1'-binaphthyl (BN), a green emitter, 1,4-bis[2-[4-[N,N-di(p-tolyl)amino] phenyl]vinyl]benzene (DSB), and a red emitter, 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidy-l-9-enyl)-4H-pyran (DCJTB) with different doping concentrations for the first time to investigate the cascade energy transfer process. The energy transfer schemes in the co-doped thin films in photoluminescence and electroluminescence have been investigated. The results indicated that the DSB molecules acted as a bridge to deliver energy more effectively from the host (BN) to the guest (DCJTB). Meanwhile, the maximum current efficiency (C E) and power efficiency (P E) of the organic light-emitting devices (OLEDs) with the emitting layer of lower doping concentration were 13.5 cd/A and 14.1 lm/W, respectively. PMID:25977665

  12. Femtosecond Yb:KGd(WO4)2 laser oscillator pumped by a high power fiber-coupled diode

    E-print Network

    Major, Arkady

    , and W. Sibbett, "Highly efficient femtosecond Yb:KYW laser pumped by single narrow-stripe laser diodeFemtosecond Yb:KGd(WO4)2 laser oscillator pumped by a high power fiber-coupled diode laser module.major@utoronto.ca Abstract: The development and characterization of a diode-pumped ultrashort pulse Yb:KGd(WO4)2 laser

  13. Master dye laser oscillator including a specific grating assembly for use therein

    DOEpatents

    Davin, James M. (Livermore, CA)

    1992-01-01

    A dye laser oscillator for producing a tuned dye beam is disclosed herein and includes, among other components, a beam output coupling assembly, a dye cell assembly, a beam expander assembly, an etalon assembly, and a grating assembly. Each of three assemblies is vertically supported from a horizontal base so as to be readily removable from the base without interference from or interfering with the other assemblies. The particular grating assembly disclosed is specifically designed for proper optical alignment with the intended path of the dye beam to be produced and for accurate pivotal movement relative to the beam path in order to function as a coarse tuning mechanism in the production of the ultimately tuned beam.

  14. Upper hybrid wave pumped free electron laser

    SciTech Connect

    Sharma, S.C.; Tripathi, V.K. [Indian Inst. of Tech., New Delhi (India). Dept. of Physics] [Indian Inst. of Tech., New Delhi (India). Dept. of Physics

    1995-08-01

    A large upper hybrid wave has potential to be employed as a wiggler for the generation of high frequency coherent radiation via free electron laser (FEL) instability. At a density fluctuation level of a few percent, due to the upper hybrid wave, the growth time of FEL instability, with electron beam current of a few kilo ampere, turns out to be of the order of a nanosecond. The growth rate of FEL instability depends sensitively on {omega}{sub 1} and this dependence comes through v{sub osc}, the beam oscillatory velocity. However, this scheme of FEL operating suffers from a severe limitation due to the parametric instability of the upper hybrid wave. The process of parametric decay into lower hybrid and upper hybrid waves may have growth rate comparable to that of the FEL instability.

  15. Laser rods with undoped, flanged end-caps for end-pumped laser applications

    DOEpatents

    Meissner, Helmuth E. (Pleasanton, CA); Beach, Raymond J. (Livermore, CA); Bibeau, Camille (Danville, CA); Sutton, Steven B. (Manteca, CA); Mitchell, Scott (Tracy, CA); Bass, Isaac (Castro Valley, CA); Honea, Eric (Sunol, CA)

    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.

  16. Gain dynamics of a free-space nitrogen laser pumped by circularly polarized femtosecond laser pulses

    E-print Network

    Yao, Jinping; Zeng, Bin; Chu, Wei; Li, Guihua; Ni, Jielei; Zhang, Haisu; Jing, Chenrui; Zhang, Chaojin; Xu, Huailiang; Cheng, Ya; Xu, Zhizhan

    2015-01-01

    We experimentally demonstrate ultrafast dynamic of generation of a strong 337-nm nitrogen laser by injecting an external seed pulse into a femtosecond laser filament pumped by a circularly polarized laser pulse. In the pump-probe scheme, it is revealed that the population inversion between the excited and ground states of N2 for the free-space 337-nm laser is firstly built up on the timescale of several picoseconds, followed by a relatively slow decay on the timescale of tens of picoseconds, depending on the nitrogen gas pressure. By measuring the intensities of 337-nm signal from nitrogen gas mixed with different concentrations of oxygen gas, it is also found that oxygen molecules have a significant quenching effect on the nitrogen laser signal. Our experimental observations agree with the picture of electron-impact excitation.

  17. Single-frequency 1559-nm erbium-doped fiber laser pumped by a 650-nm semiconductor laser

    SciTech Connect

    Giles, C. Randy [Lucent Technologies, Bell Laboratories, Crawford Hill Laboratory, Holmdel, New Jersey 07733-0400 (United States)] Mizrahi, V. [Cienna Corporation, Hanover, Maryland 21076 (United States)

    1997-08-01

    A single-frequency laser with a 2-cm-length erbium-doped fiber and fiber-grating coupler mirrors was operated successfully with a 650-nm semiconductor pump laser. Laser pump threshold was 0.91-mW and 34-{mu}W output power at 1559 nm was obtained for 6-mW pump power. {copyright} 1997 Optical Society of America

  18. Development of lasers optimized for pumping Ti:Al2O3 lasers

    NASA Technical Reports Server (NTRS)

    Rines, Glen A.; Schwarz, Richard A.

    1994-01-01

    Laboratory demonstrations that were completed included: (1) an all-solid-state, broadly tunable, single-frequency, Ti:Al2O3 master oscillator, and (2) a technique for obtaining 'long' (nominally 100- to 200-ns FWHM) laser pulses from a Q-switched, Nd oscillator at energy levels commensurate with straightforward amplification to the joule level. A diode-laser-pumped, Nd:YLF laser with intracavity SHG was designed, constructed, and evaluated. With this laser greater than 0.9 W of CW, output power at 523.5 nm with 10 W of diode-laser pump power delivered to the Nd:YLF crystal was obtained. With this laser as a pump source, for the first time, to our knowledge, an all solid-state, single frequency, Ti:Al203 laser with sufficient output power to injection seed a high-energy oscillator over a 20-nm bandwidth was demonstrated. The pulsed laser work succeeded in demonstrating pulse-stretching in a Q-switched Nd:YAG oscillator. Pulse energies greater than 50-mJ were obtained in pulses with 100- to 200-ns pulsewidths (FWHM).

  19. Performance of a continuous-wave forsterite laser with krypton ion, Ti:sapphire, and Nd:YAG pump lasers

    SciTech Connect

    Carrig, T.J.; Pollock, C.R. [Cornell Univ., Ithaca, NY (United States). School of Electrical Engineering] [Cornell Univ., Ithaca, NY (United States). School of Electrical Engineering

    1993-11-01

    The authors characterize continuous-wave operation of a chromium-doped forsterite (Cr{sup 4+}:Mg{sub 2}SiO{sub 4}) laser using krypton ion, Ti:sapphire, and Nd:YAG lasers as pump sources. Measurements were made pumping at 647 nm and 676 nm with the krypton ion laser, between 690 and 1,010 nm with the Ti:sapphire laser and at 1.06 {mu}m with the Nd:YAG laser. Threshold pump powers and slope efficiencies are compared for output coupler transmissions varying between 1 and 15.5%. Room temperature operation was only achieved using the Nd:YAG pump laser. Forsterite laser output power as a function of both temperature and pumping wavelength is discussed.

  20. Longitudinal discharge pumped low-pressure XeCl laser

    NASA Astrophysics Data System (ADS)

    Fedorov, A. I.

    2013-10-01

    We have studied output parameters of a XeCl and a N2 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-1 atm-1 was reached using helium as a buffer gas. With argon-containing and buffer-free mixtures, it was 1.5 J L-1 atm-1. The N2 laser generated 2.5-ns FWHM pulses with an average power of 0.35 mW and output energy of 0.05 mJ.