Generation of high flux, highly coherent extreme ultraviolet radiation in a gas cell
Lap Van Dao, Sven Teichmann, Jeff Davis, and Peter Hannaford
We report the generation of extreme ultraviolet radiation with high photon flux (1010 photon/cm s), high spatial coherence (up to 0.95), and good spatial beam profile by high-order harmonic generation in various noble gases (argon, neon, and helium) in a gas cell. The photon flux was determined usi ... [J. Appl. Phys. 104, 023105 (2008)] published Wed Jul 23, 2008.
Well-conditioned multiple laser Mueller matrix ellipsometer
Frantz Stabo-Eeg, Morten Kildemo, Ingar Stian Nerbo, and Mikael Lindgren
We report on the design and performance test of a multiple laser Mueller matrix ellipsometer (MME). The MME is well conditioned due to the integration of the recently reported achromatic 132-deg compensators based on biprisms, in combination with high-quality Glan-Thompson polarizers. The system cur ... [Opt. Eng. 47, 073604 (2008)] published Wed Jul 23, 2008.
Erratum: Coherent Multiheterodyne Spectroscopy Using Stabilized Optical Frequency Combs [Phys. Rev. Lett. [bold 100], 013902 (2008)]
Ian Coddington, William C. Swann, and Nathan R. Newbury
... [Phys. Rev. Lett. 101, 049901 (2008)] published Wed Jul 23, 2008.
cw electro-optical characteristics and preliminary reliability of double-heterostructure GaAs-Al[sub x]Ga[sub 1 - x]As lasers grown by molecular beam epitaxy
W. T. Tsang, R. L. Hartman, H. E. Elder, and W. R. Holbrook
The cw threshold currents and total forward series resistances of the proton-bombarded stripe-geometry lasers fabricated from GaAs-AlGaAs double-heterostructure (DH) wafers grown by molecular beam epitaxy (MBE) are at least as low as those similar-geometry lasers grown by liquid phase epitaxy. Yield ... [Appl. Phys. Lett. 37, 141 (2008)] published Tue Jul 22, 2008.
Phonon contribution to double-heterojunction laser operation
N. Holonyak, Jr., B. A. Vojak, W. D. Laidig, K. Hess, J. J. Coleman et al.
Laser data (77 and 300 K) are presented on two photopumped undoped metallorganic chemical vapor deposition AlGaAs -GaAs heterostructures with active regions consisting of: (i) a thick GaAs layer (L ~1500 A) coupled to an auxiliary quantum-well array of seven small L ~50 A coupled GaAs layers, and (i ... [Appl. Phys. Lett. 37, 136 (2008)] published Tue Jul 22, 2008.
Two-photon pumped cw laser
G. D. Willenberg, C. O. Weiss, and H. Jones
Infrared-microwave pumping of two-photon transitions in NH has led to cw laser emission of a number of NH transitions in the far infrared. ... [Appl. Phys. Lett. 37, 133 (2008)] published Tue Jul 22, 2008.
High-power laser discharge stabilization with magnetic fields
H. J. J. Seguin, C. E. Capjack, D. Antoniuk, and K. A. Nam
A new discharge stabilization technique for high-powered gas lasers is described. Profiled magnetic fields interacting with electron and ion sheaths at or near the electrode surfaces inhibit growth of electrothermal plasma instabilities and increase power loading by an order of magnitude. The techni ... [Appl. Phys. Lett. 37, 130 (2008)] published Tue Jul 22, 2008.
Analysis of diode lasers with lateral spatial variations in thickness
W. Streifer, R. D. Burnham, and D. R. Scifres
Diode lasers with active and/or cladding regions whose thicknesses vary spatially parallel to the p-n junction are analyzed. It is shown that lateral real-refractive-index waveguiding occurs and that a diffusion gradient exists which propels the injected charges into the lasing modal volume. Lateral ... [Appl. Phys. Lett. 37, 121 (2008)] published Tue Jul 22, 2008.
Efficient simple sealed-off CO laser at room temperature
P. J. M. Peters, W. J. Witteman, and R. J. Zuidema
A sealed-off cw CO laser with gold electrodes is described. With this simple device we measured a constant, long-life output power of more than 29 W/m and a maximum efficiency of 15% at room temperature. No auxiliary features, such as a palladium hydrogen extraction tube, are necessary. ... [Appl. Phys. Lett. 37, 119 (2008)] published Tue Jul 22, 2008.
Compact 0.1 TW CO[sub 2] laser system
K. O. Tan, D. J. James, J. A. Nilson, N. H. Burnett, and A. J. Alcock
A 3 atm, 9 x 9 x 100 cm uv preionized self-sustained discharge module has been used as the basis for a compact nanosecond pulse CO laser system. Up to 60 J has been extracted from the device in an ~600 ps pulse. The high degree of gain uniformity and fast gain risetime demonstrated by the present de ... [Rev. Sci. Instrum. 51, 776 (2008)] published Tue Jul 22, 2008.
Stable CO[sub 2] and N[sub 2]O laser design
J. E. Thomas, M. J. Kelly, J.-P. Monchalin, N. A. Kurnit, and A. Javan
A complete working design for highly stable grating controlled NO and CO lasers is presented. The lasers are suitable for general high resolution spectroscopy, frequency mixing and clock applications. ... [Rev. Sci. Instrum. 51, 240 (2008)] published Tue Jul 22, 2008.
Development of a high-repetition-rate mini-TEA CO[sub 2] laser
N. Menyuk and P. F. Moulton
A 1.8 cm active volume gas-recirculating mini-TEA CO laser of relatively simple design is described. The laser is capable of operating at 500 Hz with an average output of 10 W. The device is line tunable over ~50 CO laser frequencies, has operated with up to 34 J/l output density and has a nearly di ... [Rev. Sci. Instrum. 51, 216 (2008)] published Tue Jul 22, 2008.
Laser power-per-line analyzer
Richard L. Fusek, M. Cem Gokay, and Joseph S. Marcheski
The power-per-line analyzer is an instrument designed to provide a continuous real-time display of any laser spectra on an oscilloscope. In this article the HF and DF laser version of this instrument is described. A new continuous drive and electronic calibration method are used, eliminating the nee ... [Rev. Sci. Instrum. 51, 213 (2008)] published Tue Jul 22, 2008.
Laser-beam attenuation for spatial profiling of small focal spots
D. B. Nichols and R. B. Hall
We describe an attenuation scheme for high-power laser beams which uses only two optical surfaces and is continuously variable over several orders of magnitude. We demonstrate its application to the spatial profiling of a pulsed DF laser focal spot with 10 cm diameter and >~10 W/cm peak irradiance. ... [Rev. Sci. Instrum. 51, 1131 (2008)] published Tue Jul 22, 2008.
Properties of pulsed gas lasers pumped by LC inversion circuit made of BaTiO[sub 3] and SrTiO[sub 3] series ceramic capacitors
Koji Matsumoto, Kazuhiko Sueoka, Minoru Obara, Tomoo Fujioka, and Hirotaka Yamamoto
Properties of pulsed gas lasers pumped by LC inversion circuit made of BaTiO and SrTiO series ceramic capacitors were experimentally investigated. The effects of a decrease in capacitance at higher charging voltages on TEA CO and TE N laser performances were clarified in terms of discharge voltage, ... [Rev. Sci. Instrum. 51, 1046 (2008)] published Tue Jul 22, 2008.
Versatile High-throughput filter for altering the spectrum of multiple-frequency lasers
N. R. Greiner
This device filters any desired subset of frequencies from a multiple-frequency laser without reducing substantially either the power in the remaining frequencies or the optical quality of the reconstructed beam. It should be useful in multiple-frequency laser photochemistry and the probing of multi ... [Rev. Sci. Instrum. 51, 392 (2008)] published Tue Jul 22, 2008.
Ultraminiature high-power gas discharge lasers excited through high dielectric constant ceramic materials
V. Hasson, H. M. von Bergmann, and E. G. Jones
The authors show that millimeter-size high-pressure UV nitrogen lasers can be excited through high dielectric constant materials and provide peak beam powers of 1010 W. ... [Rev. Sci. Instrum. 51, 384 (2008)] published Tue Jul 22, 2008.
Production of flat top beam profiles for high energy lasers
R. E. Grojean, D. Feldman, and J. F. Roach
Production of uniform (flat top) high energy laser beam profiles with relatively little beam energy loss is possible through the use of a modified kaleidoscope, multiple reflection beam scrambler. ... [Rev. Sci. Instrum. 51, 375 (2008)] published Tue Jul 22, 2008.
Estimating threshold reduction for spin-injected semiconductor lasers
I. Vurgaftman, M. Holub, B. T. Jonker, and J. R. Meyer
The magnitude of threshold reduction in a semiconductor laser with electron spin injection is shown to depend on such intrinsic properties of the active region as the dominant recombination mechanism, the ratio of hole-to-electron densities of states, the active-region doping, and the available mate ... [Appl. Phys. Lett. 93, 031102 (2008)] published Mon Jul 21, 2008.
Effect of waveguide sidewall roughness on the threshold current density and slope efficiency of quantum cascade lasers
Fatima Toor, Deborah L. Sivco, Hao E. Liu, and Claire F. Gmachl
We report on a study to determine the effect of waveguide sidewall roughness on quantum cascade (QC) laser performance using two two-wavelength heterogeneous QC laser structures, one with emission wavelengths of 7.0 [mu]m/11.2 [mu]m, and the other with 8.7 [mu]m/12.0 [mu]m. For the range of roug ... [Appl. Phys. Lett. 93, 031104 (2008)] published Mon Jul 21, 2008.
Design, implementation and testing of a fuzzy control scheme for laser welding
J. M. Jauregui, B. J. Aalderink, R. G. K. M. Aarts, J. Olde Benneker, and J. Meijer
A fuzzy logic controller (FLC) scheme has been developed for laser welding. Process light emissions are measured and combined to determine the current status of the welding process. If the process is not in a desired welding state, the FLC will adapt the laser power. The FLC has been demonstrated fo ... [J. Laser Appl. 20, 146 (2008)] published Fri Jul 18, 2008.
Dynamic light scattering in turbid nonergodic media
Martin Medebach, Norbert Freiberger, and Otto Glatter
We here present a new device based on dynamic light scattering (DLS) for measuring kinetics in turbid and nonergodic systems. This flat cell light scattering instrument has been developed in our laboratory and is based on an original flat cell instrument employing cells of varying thickness in order ... [Rev. Sci. Instrum. 79, 073907 (2008)] published Fri Jul 18, 2008.
Turn-on dynamics and modulation response in semiconductor quantum dot lasers
Kathy Ludge, Moritz J. P. Bormann, Ermin Malic, Philipp Hovel, Matthias Kuntz et al.
We show that the dynamic response of electrically pumped semiconductor quantum dot lasers can be quantitatively understood by including the strongly nonlinear character of electron-electron scattering processes. The numerical simulations presented here combine a microscopic approach used for calcula ... [Phys. Rev. B 78, 035316 (2008)] published Thu Jul 17, 2008.