Output Power (output + power)

Distribution by Scientific Domains
Distribution within Physics and Astronomy

Kinds of Output Power

  • laser output power
  • maximum output power

  • Selected Abstracts

    Crystal growth, optical properties, and continuous-wave laser operation of Nd3+ -doped CaNb2O6 crystal

    LASER PHYSICS LETTERS, Issue 10 2009
    Y. Cheng
    Abstract Laser crystal Nd:CaNb2O6 with excellent quality has been grown by Czochralski technique. The effective segregation coefficient of Nd3+ was studied by X-ray fluorescence method. The polarized absorption spectra and the fluorescence spectra of Nd:CaNb2O6 were measured at room temperature. The peak absorption cross section was calculated to be 6.20210,20 cm2with a broad FWHM of 7 nm at 808 nm for E , a light polarization. The emission cross section at 1062 nm is 9.87 10,20 cm2. We report what we believe to be the first demonstration of the continuous-wave Nd:CaNb2O6 laser operation under diode pumping. Output power of 1.86 W at 1062 nm was obtained with a slope efficiency of 19% in the CW regime. ( 2009 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Experimental study of a high-power CW diode-sidepumped Nd:YAG rod laser

    F. Hajiesmaeilbaigi
    Abstract In this paper we report on the characterization of a diode-side-pumped Nd:YAG rod laser operating at 300 W CW output power. The simulated and measured pump energy distributions in the crystal are compared. The thermal lens effect of the Nd:YAG have been experimentally investigated, and its influence on the performance of the laser are discussed. Output power and the beam quality of the laser under different resonator mirrors and rod end-face curvatures have been experimentally studied. The optical-to-optical and electrical-to-optical efficiencies are 28.5% and 11%, respectively. The beam parameter product is 40 mm mrad and the instability of laser is about 3%. ( 2005 by Astro, Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Room temperature electroluminescence from multilayer GeSi heterostructures

    A. A. Tonkikh
    Abstract Details of silicon diodes with Ge/Si multilayer quantum dot heterostructures embedded in the Si p,n junction grown by molecular beam epitaxy emitting in the range of 1.4,1.7 m at room temperature and continuous injection pumping are discussed. Output power of the light emitting diode reaches 1 W/cm2 at applied current density of 2 A/cm2. Photoluminescence and transmission electron microscopy show that the origin of intense luminescence is defect free stacked Ge quantum dot array formed inside the structure. It is shown that doping by antimony improves structure quality and increases photoluminescence efficiency at room temperature. ( 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Digital Analysis of Myocardial Contrast Echocardiography: A Clinical Study Using an Air-Filled Agent in Normal Subjects

    ECHOCARDIOGRAPHY, Issue 3 2000
    The purpose of the present study was to determine whether direct digital image analysis would allow improved detection of myocardial contrast. Eighteen normal subjects were recruited and separated into two groups. In group 1, the time-brightness curves of the left ventricular cavity and three myocardial perfusion beds were formed from digitized video tape, with output power and imaging time as secondary variables. In group 2, curves constructed from direct polar digital data were compared, with fundamental and second harmonic image formation as variables. In group 1 subjects, using fundamental imaging, the area under the curve in the left ventricular cavity increased slightly with intermittent imaging. No consistent myocardial opacification was identified. In group 2 subjects, using intermittent imaging, the area under the myocardial curve and peak intensity increased with high output second harmonic imaging in the left anterior descending and right coronary artery regions. Intermittent, second harmonic imaging and digital processing can demonstrate myocardial contrast even with an air-filled agent. [source]

    Proposal and development of radial air-gap coreless generator suitable for small wind turbine used in urban area

    Toshiyuki Takahashi
    Abstract Independent distributed power generation using small wind turbines is becoming more widespread as wind power generation increases. Installation of small wind turbines in densely populated urban areas is not only useful from the viewpoint of extracting wind power sources in weak-wind areas but also for making renewable energy easier to access when power supplies are closer to consumers. It is from this point of view that the authors proposed "urban wind power generation" using a collective system with a number of small vertical wind turbines, and have developed a suitable generator for low-speed vertical wind turbines such as a Savonius windmill. Based on a standard coreless generator, the proposed generator is designed to make the direction of the magnetic flux radial in order to install the magnets and coils on the outer end of the generator. The change of magnet composition and flux direction maximizes the speed of the flux change and output voltage within a limited space. With the above configuration, the power of the proposed generator is independent of the diameter. In this report, the authors describe and evaluate the fundamental performance of a prototype of the proposed generator. Based on the experiments, a maximum output power of 283 W was obtained. The obtained starting torque is small enough to begin rotation under weak wind conditions of no more than 1 m/s. Therefore, it is clear that the proposed "radial" coreless generator is suitable for self-starting and producing high power at low wind speed. 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(1): 26, 34, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20695 [source]

    Effects of output power fluctuation on short-circuit current of induction-type wind power generators

    Teruhisa Kumano
    Abstract Effects of the fluctuation inherent in wind speed are studied by a probabilistic method. The random variation in wind speed is responsible for random behavior in output power and internal voltage of a wind power generator. In case of fault occurrence at the instant of high internal voltage, the resultant short-circuit current will be big, and vice versa. The DC component is also affected. According to the study, 2.4% and 1.3% increase of short-circuit current in AC and DC components are observed respectively in a large variation case. This implies that the wind speed variation should be considered for accurate short-circuit study. 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(3): 27,36, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20721 [source]

    Output power leveling of wind turbine generators using pitch angle control for all operating regions in wind farm

    Tomonobu Senjyu
    Abstract Effective utilization of renewable energies such as wind energy instead of fossil fuels is desirable. Wind energy is not constant and windmill output is proportional to the cube of the wind speed, which causes the generated power of wind turbine generators (WTGs) to fluctuate. In order to reduce the output power fluctuation of wind farms, this paper presents an output power leveling control strategy for a wind farm based on both the average wind farm output power and the standard deviation of the wind farm output power, a cooperative control strategy for WTGs, and pitch angle control using a generalized predictive controller (GPC) in all WTG operating regions. Simulation results using an actual detailed model for wind farm systems show the effectiveness of the proposed method. 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 158(4): 31, 41, 2007; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/eej.20448 [source]

    Indirect laser-induced fluorescence detection for capillary electrophoresis using a frequency-doubled diode laser

    ELECTROPHORESIS, Issue 3 2003
    Natalia Ragozina
    Abstract A blue (452 nm) frequency-doubled diode laser with a quasi-cw optical output power of 10 ,W is used for indirect laser-induced fluorescence detection in combination with the capillary electrophoretic separation of inorganic anions. As fluorescing probe ion the anion of 8-hydroxypyrene-1,3,6-trisulfonic acid (HPTS) was selected having an absorption maximum of 454 nm in alkaline medium. Employing a capillary coated with linear acrylamide, baseline separation of eight inorganic anions was possible within 5 min. With a separation buffer containing 50 ,molL -1 HPTS and 10 mmolL -1 lysine the limits of detection for sulfate, nitrite, nitrate, azide, thiocyanate, and chlorate were between 0.9 and 4.7 ,molL -1. Separation of chloride and sulfate was achieved by adding 0.25 mmolL -1 calcium hydroxide to the separation buffer. Inorganic anions in several mineral and tap water samples have been determined with the technique developed and results are compared to data obtained by ion chromatography in combination with conductivity detection after conductivity suppression. [source]

    980-nm Laser-Driven Photovoltaic Cells Based on Rare-Earth Up-Converting Phosphors for Biomedical Applications

    Zhigang Chen
    Abstract A prerequisite for designing and constructing wireless biological nanorobots is to obtain an electrical source that is continuously available in the operational biological environment. Herein the first preparation of 980-nm laser-driven photovoltaic cells (980LD-PVCs) by introducing of a film of rare-earth up-converting nanophosphors in conventional dye-sensitized solar cells is reported. Under the irradiation of a 980-nm laser with a power of 1,W, the visible up-converting luminescence of rare-earth nanophosphors can be efficiently absorbed by the dyes in 980LD-PVCs so that they exhibit a maximal output power of 0.47 mW. In particular, after being covered with 1 to 6 layers of pig intestines (thickness: ca. 1,mm per layer) as a model of biological tissues, 980LD-PVCs still possess a maximal output power of between 0.28 and 0.02,mW, which is efficient enough to drive many kinds of biodevices. This research opens up the possibility of preparing and/or developing novel electrical sources for wireless biological nanorobots and many other biodevices. [source]

    Fabrication and Application of an Oxide Thermoelectric System

    Ryoji Funahashi
    A plate-shaped thermoelectric module was prepared using 140 pairs of p -type Ca3Co4O9 (Co-349) and n -type LaNiO3 (Ni-113) bulks. The hot-pressed thermoelectric oxide bulks were connected with an Ag paste, incorporating oxide powder, and Ag sheets. The module's open-circuit voltage increases with increasing hot-side temperature (TH) and reaches 4.5 V at a TH of 1072 K in air. No deterioration in output power was seen when power generation was carried out 10 times at a TH of 723 K with intermediate cooling to room temperature. The module was successfully used to charge a lithium-ion battery in a mobile phone. Thermoelectric modules composed of p -type Co-349 and n -type CaMnO3 (Mn-113) bulks, which have a pipe shape, were constructed using Ag electrodes and stainless-steel tubes. The devices were connected with the stainless-steel tube coated with ZrO2 by thermal spray using a dielectric paste composed of silica glass and iron oxide. Power generation was carried out in flame by combustion of natural gas. Water flowed inside the stainless-steel tube for cooling. One module consisting of 54 pairs of legs can generate 1.5 V, 0.28 W, and steam simultaneously by installing in an instantaneous water heater. Power generation was carried out four times with intermediate cooling. Deterioration in the open-circuit voltage of the module was not observed after the fourth combustion. [source]

    Full-duplex analogue/digital data transmission using lasers coupled to GI fibre and its application

    Masayoshi Kamiya
    Abstract This paper describes a low-cost version of a full-duplex optical fibre analogue/digital data transmission link whose practical implementation is simplified by using a pair of laser diodes, each having a built-in photodiode for monitoring the laser output power, and its application to vibration test data transmission. The transmission link sends digital data of up to 9600 bps in one direction, and analogue data of DC to 100 kHz and image data specified by an NTSC colour video signal in the opposite direction, all at the same time through one GI optical fibre. Being simple in configuration and stable against noise, this type of link has a variety of applications within factory, home and offices. Copyright 2001 John Wiley & Sons, Ltd. [source]

    Comparison of evaporative inlet air cooling systems to enhance the gas turbine generated power

    Mohammad Ameri
    Abstract The gas turbine performance is highly sensitive to the compressor inlet temperature. The output of gas turbine falls to a value that is less than the rated output under high temperature conditions. In fact increase in inlet air temperature by 1C will decrease the output power by 0.7% approximately. The solution of this problem is very important because the peak demand season also happens in the summer. One of the convenient methods of inlet air cooling is evaporating cooling which is appropriate for warm and dry weather. As most of the gas turbines in Iran are installed in such ambient conditions regions, therefore this method can be used to enhance the performance of the gas turbines. In this paper, an overview of technical and economic comparison of media system and fog system is given. The performance test results show that the mean output power of Frame-9 gas turbines is increased by 11 MW (14.5%) by the application of media cooling system in Fars power plant and 8.1 MW (8.9%) and 9.5 MW (11%) by the application of fog cooling system in Ghom and Shahid Rajaie power plants, respectively. The total enhanced power generation in the summer of 2004 was 2970, 1701 and 1340 MWh for the Fars, Ghom and Shahid Rajaie power plants, respectively. The economical studies show that the payback periods are estimated to be around 2 and 3 years for fog and media systems, respectively. This study has shown that both methods are suitable for the dry and hot areas for gas turbine power augmentation. Copyright 2007 John Wiley & Sons, Ltd. [source]

    Performance characteristics and modelling of a micro gas turbine for their integration with thermally activated cooling technologies

    Adrin Vidal
    Abstract We have developed a simple model of a micro gas turbine system operating at high ambient temperatures and characterized its performance with a view to integrating this system with thermally activated cooling technologies. To develop and validate this model, we used experimental data from the micro gas turbine test facility of the CREVER research centre. The microturbine components were modelled and the thermodynamic properties of air and combustion gases were estimated using a commercial process simulator. Important information such as net output power, microturbine fuel consumption and exhaust gas mass flow rate can be obtained with the empirical correlations we have developed in this study. This information can be useful for design exhaust gas fired absorption chillers. Copyright 2006 John Wiley & Sons, Ltd. [source]

    Study of a longitudinal flux permanent magnet linear generator for wave energy converters

    O. Danielsson
    Abstract A directly coupled linear permanent magnet generator of longitudinal flux-type is investigated. The generator will be used for power take-off in a wave energy converter. A combined field- and circuit model, solved by a time stepping finite element technique, is used to model and analyse the electromagnetic behaviour of the machine. A large number of simulations form the basis of a design study where the influence of armature current level, number of cables per slot, and pole width is investigated with respect to efficiency, generator size, and the load angle. A case study is performed for a chosen generator design. The electromagnetic behaviour is examined both for nominal load and for overloads. The generator has a nominal output power of 10 kW for a constant piston speed of 0.7 ms,1. The electromagnetic efficiency at nominal load is 86.0%, the load angle 6.6, and the power fluctuation 1.3%. At 300% overload the load angle barely exceeds 12 and the cable temperature is below 25C provided that the stator back is thermally connected to the sea water. The numerical calculations have been verified for small speeds by experiments. Copyright 2006 John Wiley & Sons, Ltd. [source]

    On mass transport in an air-breathing DMFC stack

    G. Q. Lu
    Abstract An 8-cell air-breathing direct methanol fuel cell (DMFC) stack with the active area of 5 cm2 of each cell has been developed. Stainless steel plates of 500 m thickness with flow channels were fabricated using photochemical etching method as the current collectors. Different conditioning methods for membrane electrode assembly (MEA) activation were discussed. With proper control of water crossover to the cathode, cathode flooding was avoided in the DMFC stack. Methanol crossover at open circuit voltage (OCV) in the air-breathing DMFC was measured. Further, it was found that flow maldistribution might occur in the parallel flow field of the stack, making carbon dioxide gas management at the anode necessary. Using humidified hydrogen in the anode with a high flow rate, the oxygen transport limiting current density was characterized and found to be sufficient in the air-breathing cathode. The stack produced a maximum output power of 1.33 W at 2.21 V at room temperature, corresponding to a power density of 33.3 mW cm,2. Copyright 2005 John Wiley & Sons, Ltd. [source]

    Multiharmonic manipulation for highly efficient microwave power amplifiers

    Paolo Colantonio
    Abstract Multiharmonic manipulation is presented as the most effective solution to improve power amplifier (PA) efficiency performances. Remarkable improvements in output power, power gain and power-added efficiency (PAE) are demonstrated, properly manipulating the input and output second and third harmonics, as compared to more classical design approaches. Experimental results at 5GHz confirm the feasibility, the validity and effectiveness of the proposed approach, increasing the maximum measured power-added efficiency from 39% to 61% 2001 John Wiley & Sons, Inc. Int J RF and Microwave CAE 11: 366,384, 2001 [source]

    High-power RF photodiodes and their applications

    LASER & PHOTONICS REVIEWS, Issue 1-2 2009
    T. Nagatsuma
    Abstract There has been an increasing interest in photonic generation of RF signals in the millimeter-wave (30 GHz,300 GHz) and/or terahertz-wave (0.1 THz,10 THz) regions, and photodiodes play a key role in it. This paper reviews recent progress in the high-power RF photodiodes such as Uni-Traveling-Carrier-Photodiodes (UTC-PDs), which operate at these frequencies. Several approaches to increasing both the bandwidth and output power of photodiodes are discussed, and promising applications to broadband wireless communications and spectroscopic sensing are described. [source]

    1064 nm Nd:YAG laser intracavity pumped at 946 nm and sum-frequency mixing for an emission at 501 nm

    Y.F. L
    Abstract We present for the first time a Nd:YAG laser emitting at 1064 nm intracavity pumped by a 946 nm diode-pumped Nd:YAG laser. A 809 nm laser diode is used to pump the first Nd:YAG crystal emitting at 946 nm, and the second Nd:YAG laser emitting at 1064 nm intracavity pumped at 946 nm. Intracavity sum-frequency mixing at 946 and 1064 nm was then realized in a LBO crystal to reach the cyan range. We obtained a continuous-wave output power of 485 mW at 501 nm with a pump laser diode emitting 25.4 W at 809 nm. ( 2010 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Continuous wave and passively Q-switched laser performance of the mixed crystal Nd:Lu0.15Y0.85VO4

    S. Zhang
    Abstract Laser characteristics of a novel mixed laser crystal Nd:Lu0.15Y0.85VO4 was investigated. It is attractive for Q-switching with high repetition rate and short pulse width due to its suitable stimulated emission cross-section and short upper level lifetime. Continuous wave (CW) output power of 8.18 W was obtained at the pump power of 18.9 W, corresponding to the optical conversion efficiency of 43.3% and the slope efficiency of 47%. In the passive Q-switching operation, the minimum pulse width attained was 7.8 ns, with the pulse repetition frequency of 23.2 kHz, with the single pulse energy and peak power estimated to be 94.8 ,J and 12.2 kW, respectively. ( 2010 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Tunable narrow linewidth Tm3+ -doped silica fiber laser with an intracavity taper

    Y. Zhang
    Abstract Using an intracavity long fiber taper, the 793 nm diode laser (LD) clad-pumped tunable narrow linewidth Tm3+ -doped silica fiber laser was realized. The intracavity long taper was fabricated directly on the Tm3+ -doped fiber by heating and stretching method, and located several centimeters from the output fiber end. The fiber laser cavity was combined by the fiber end Fresnel reflection and a dichroic. The fiber laser had a maximal output power of 5.86 W at 1927.2 nm, with a narrow linewidth of 148 pm. By stretching or bending the taper, the output laser center wavelength could be tuned from 1910.6 nm to 1958.1 nm with a variable spectrum width ranging from 92 , 148 pm. ( 2010 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Single linearly polarized, widely tunable Yb3+ -doped fiber laser with alternative polarization and wavelength

    D.-F. Liu
    Abstract A novel single linearly polarized, widely tunable Yb3+ -doped fiber laser with alternative two orthogonal polarization (wavelength) laser beams was proposed and demonstrated experimentally. Using a polarization beam splitting (PBS) as the separating of the two tunable laser beams in a linear Yb3+ -doped fiber cavity, the laser generates two alternatively tunable wavelength laser. Beam 1 is from 1001.9 nm to 1083.4 nm with single linear polarization and 368 mW (at 1030.1 nm) output power. Beam 2 is from 1000.0 nm to 1082.5 nm with 395 mW (at 1018.4 nm) output power and orthogonally polarized with beam 1. In addition, the laser can also work in widely tunable two wavelengths oscillating simultaneously. ( 2010 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Broadband wavelength-tunable single-longitudinalmode erbium-doped fiber ring laser using saturable-absorber filter

    C.H. Yeh
    Abstract In this paper, a broadband wavelength-tunable erbiumdoped fiber (EDF) ring laser with single longitudinal mode (SLM) output achieving 82.6 nm lasing bandwidth from 1481.0 to 1563.6 nm is proposed and experimentally demonstrated. For the proposed laser scheme, the S- and C-band erbium-doped fiber amplifiers (EDFAs) in parallel structure are used to serve as the gain medium for broadband wavelength tuning. Furthermore, we use a saturable-absorber filter (SAF) inside the fiber cavity to serve as a narrow band filter to guarantee a SLM operation. Besides, the performance of output power, wavelength, side-mode suppression ratio (SMSR) and stability are also analyzed and discussed. ( 2010 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    8.5 W room temperature continuous wave operation of a Ho:LuAG laser

    LASER PHYSICS LETTERS, Issue 12 2009
    X.M. Duan
    Abstract We report the continuous wave Ho:LuAG laser operated at room temperature. Using the diode-pumped Tm:YLF laser as a pumping source, maximum output power of 8.5 W at 2100 nm was obtained under the incident pump power of 18.4 W, corresponding to a slope efficiency of 51.3% and a conversion efficiency of 46.2%. ( 2009 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Diode-pumped passively Q-switching mode-locked Nd:Gd0.5Y0.5VO4/V3+:YAG laser at 1.34, m

    LASER PHYSICS LETTERS, Issue 11 2009
    H.-T. Huang
    Abstract A diode-pumped passively Q-switching mode-locked Nd:Gd0.5Y0.5VO4 laser at 1.34 , m using V3+:YAG as the saturable absorber has been demonstrated for the first time to the best of our knowledge. At the pump power of 7 W, the maximum average output power of 0.83 W and Q-switched pulse repetition rate of 140 kHz were obtained with absorber's initial transmission of 96%, with the corresponding Q-switched pulse energy estimated to be 6 , J. The duration of mode-locked pulse within Q-switched envelop was estimated to be 750 ps with 333.3 MHz repetition rate. ( 2009 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Diode-pumped doubly passively Q-switched Nd:LuVO4 laser with Cr4+:YAG saturable absorber and GaAs output coupler

    LASER PHYSICS LETTERS, Issue 10 2009
    K. Cheng
    Abstract A diode-pumped doubly passively Q-switched Nd:LuVO4 laser with Cr4+:YAG saturable absorber and GaAs output coupler is realized. This laser can generate a shorter and more symmetric pulse profile when compared with pure GaAs. By using two Cr4+:YAG saturable absorbers with different small-signal transmissions T0 = 0.71 and T0 = 0.81, the maximum average output power are 1.15 W and 1.31 W at the incident pump power of 11.23 W, corresponding to optical conversion efficiencies of 10.2% and 11.7%. At the same incident pump power, the minimum pulse widths of 4.18 ns and 5.42 ns can be obtained at T0 = 0.71 and T0 = 0.81, respectively. The pulse repetition rate and the single-pulse peak power of the laser are also measured. ( 2009 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Diode-pumped passively mode-locked Yb3+ -doped yttrium lanthanum oxide ceramic laser

    W. Li
    Abstract A diode-pumped picosecond laser was demonstrated with Yb3+ -doped yttrium lanthanum oxide transparent laser ceramic Yb:(Y1,xLax)2O3 (x = 0.1), which was fabricated with nanopowders and sintered in H2 atmosphere. Passive modelocking was realized for the first time to our knowledge with a semiconductor saturable absorber mirror, generating pulses of 174 ps at the central wavelength 1032.5 nm with the average output power 162 mW under a diode-laser pump power of 3.2 W. ( 2009 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    High power L-band erbium-doped fiber laser pumped by a C-band superfluorescent source

    S.-P. Chen
    Abstract The C-band is demonstrated to be suitable for pumping L-band erbium-doped fiber laser (EDFL) with a broad pumping band. A high power C-band superfluorescent fiber source (SFS) peaked at 1545 nm with output power of 1.86 W is constructed and utilized as pump source for L-band EDFL. Based on this, an all single-mode-fiber L-band EDFL emitting at 1591.9 nm with 1.19 W output power is obtained. The laser exhibits a high conversion efficiency of 64.0% with a high ASE extinction ratio of 66 dB and a narrow bandwidth of less than 0.08 nm. ( 2007 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Actively Q-switched, diode pumped thulium laser

    LASER PHYSICS LETTERS, Issue 12 2007
    J.K. Jabczynski
    Abstract 6 W of output power and near 50% slope efficiency with respect to absorbed pump power was demonstrated in freerunning mode for a short, 40-mm long resonator. The uncoated, with 3.5% dopant of thulium YLF rod of.3 8 mm size wrapped with indium foil was mounted in copper heat-sink maintaining 293 K temperature of coolant water and inserted in a short, 40-mm long resonator. For pumping the fiber coupled (0.4 mm core diameter) laser diode bar at 792-nm wavelength was deployed. The fused silica acousto-optic modulator with above 80% diffraction efficiency for 25-W power of RF was taken as the Q-switch for such a laser. In the best case of Qswitching mode up to 2-mJ output energy with 20-ns pulse duration corresponding to 100-kW peak power was demonstrated for rep. rate of a few Hz. Emission wavelength was around 1904 nm for both free-running and Q-switching regimes. ( 2007 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    Edge-pumped asymmetric Yb:YAG/YAG thin disk laser

    LASER PHYSICS LETTERS, Issue 10 2007
    Q. Liu
    Abstract An edge-pumping scheme for a quasi-three-level solid-state laser using asymmetric crystal is reported. The scheme uses a thin disk laser configuration with the pump light incident from disk edges. The pump light propagates through the disk along the zigzag path and repeatedly passes the gain medium, thus improving the pump uniformity and absorption efficiency. A maximum output power of over 123 W was achieved from an edge-pumped composite Yb:YAG/YAG thin disk laser, with slope efficiency of 34.8% and beam quality M2 , 20. ( 2007 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

    A c-cut Nd:GdVO4 solid-state laser passively Q-switched with Co2+:LaMgAl11O19 lasing at 1.34 m

    H.-J. Qi
    Abstract We investigated a high power diode-laser pumped passively Q-switched c-cut Nd:GdVO4 solid-state laser, lasing at 1.34 m, with a Co2+:LaMgAl11O19 saturable absorber. With the optimum output coupler transmission T = 5.5% and pump power of 11.5 W, the static output power of 3.01 W was obtained. The passively Q-switching operation with Co:LMA (initial transmission T0 = 90%) as saturable absorber, shows that the shortest output pulse width, the highest output power, the highest pulse repetition and the highest pulse peak power were 32 ns, 266 mW, 277 kHz, and 187 W, respectively. ( 2007 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]