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Advances in time-dependent methods for multiphoton processes

Description: This paper discusses recent theoretical results on above threshold ionization harmonic generation and high-frequency, high intensity suppression of ionization. These studies of multiphoton processes in atoms and molecules for short, intense pulsed optical lasers have been carried out using techniques which involve the explicit solution of the time-dependent Schroedinger equation. 43 refs., 5 figs.
Date: September 1, 1990
Creator: Kulander, Kenneth C.; Schafer, Kenneth J. & Krause, Jeffrey L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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AGEX II technical quarterly: Volume 1, November 1, 1994

Description: This report publishes short technical contributions on aboveground experiments that use pulsed power and laser drivers. The five papers included here cover the following: experimental colliding plasma; capacitor for Atlas Marx modules; computational modeling of magnetized target fusion experiments; ultraviolet ultrafast pump-probe laser using a Ti:sapphire laser system; and high resolution x-ray spectroscopy of a subpicosecond laser-produced silicon plasma.
Date: November 1, 1994
Creator: Ekdahl, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Analysis of Shot Noise Propagation and Amplificationin Harmonic Cascade FELs

Description: The harmonic generation process in a harmonic cascade (HC) FEL is subject to noise degradation which is proportional to the square of the total harmonic order. In this paper, we study the shot noise evolution in the first-stage modulator and radiator of a HC FEL that produces the dominant noise contributions. We derive the effective input noise for a modulator operating in the low-gain regime, and analyze the radiator noise for a density-modulated beam. The significance of these noise sources i… more
Date: December 11, 2006
Creator: Huang, Z.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of the superconducting wiggler magnets for the ATF Harmonic Generation FEL experiment

Description: In this paper, we consider the superconducting wiggler magnet under construction for the High Gain Harmonic Generation experiment (HGHG) at the Accelerator Test Facility (ATF) at BNL. This wiggler consists of an energy modulation section, a dispersion magnet and a radiator section. We present an analysis of the dispersion magnet and the end effects in the other wiggler sections. The purpose of the dispersion magnet is to convert energy modulation of the electron beam into spatial bunching. For … more
Date: October 1, 1992
Creator: Zhang, X.; Ben-Zvi, Ilan; Ingold, G.; Krinsky, S. & Yu, L. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of the superconducting wiggler magnets for the ATF Harmonic Generation FEL experiment

Description: In this paper, we consider the superconducting wiggler magnet under construction for the High Gain Harmonic Generation experiment (HGHG) at the Accelerator Test Facility (ATF) at BNL. This wiggler consists of an energy modulation section, a dispersion magnet and a radiator section. We present an analysis of the dispersion magnet and the end effects in the other wiggler sections. The purpose of the dispersion magnet is to convert energy modulation of the electron beam into spatial bunching. For … more
Date: January 1, 1992
Creator: Zhang, X.; Ben-Zvi, Ilan; Ingold, G.; Krinsky, S. & Yu, L. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analytic model of bunched beams for harmonic generation in thelow-gain free electron laser regime

Description: One scheme for harmonic generation employs free electron lasers (FELs) with two undulators: the first uses a seed laser to modulate the energy of the electron beam; following a dispersive element which acts to bunch the beam, the second undulator radiates at a higher harmonic. These processes are currently evaluated using extensive calculations or simulation codes which can be slow to evaluate and difficult to set up. We describe a simple algorithm to predict the output of a harmonic generation… more
Date: February 20, 2006
Creator: Penn, G.; Reinsch, M. & Wurtele, J.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Annual Scientific Report for DE-FG03-02NA00063 Coherent imaging of laser-plasma interactions using XUV high harmonic radiation

Description: In this project, we use coherent short-wavelength light generated using high-order harmonic generation as a probe of laser-plasma dynamics and phase transitions on femtosecond time-scales. The interaction of ultrashort laser pulses with materials and plasmas is relevant to stockpile stewardship, to understanding the equation of state of matter at high pressures and temperatures, and to plasma concepts such as the fast-ignitor ICF fusion concept and laser-based particle acceleration. Femtosecond… more
Date: May 3, 2005
Creator: Kapteyn, Prof. Henry C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Anomalous dispersion enhanced Cerenkov phase-matching

Description: The authors report on a scheme for phase-matching second harmonic generation in polymer waveguides based on the use of anomalous dispersion to optimize Cerenkov phase matching. They have used the theoretical results of Hashizume et al. and Onda and Ito to design an optimum structure for phase-matched conversion. They have found that the use of anomalous dispersion in the design results in a 100-fold enhancement in the calculated conversion efficiency. This technique also overcomes the limitatio… more
Date: November 1, 1993
Creator: Kowalczyk, T. C.; Singer, K. D. & Cahill, P. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Application considerations and compensation characteristics of shunt active and series active filters in power systems

Description: This paper characterizes typical nonlinear loads into two types of harmonic sources -harmonic current source and harmonic voltage source, which produce highly distorted currents and voltages, respectively. The conventional approach of active harmonic compensation has been the parallel type or `shunt active filter.` It is shown in this paper that the shunt active filter is effective only to harmonic current sources but not to harmonic voltage sources. On the other hand, the active filter connect… more
Date: October 1, 1996
Creator: Peng, Fang Zheng & Lai, Jih-Sheng
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Application of nonlinear wave modulation spectroscopy to discern material damage

Description: Materials containing structural damage have a far greater nonlinear elastic response than materials with no structural damage. This is the basis for nonlinear wave diagnostics of damage, methods which are remarkably sensitive to the detection and progression of damage in materials. Here the authors describe one nonlinear method, the application of harmonics and sum and difference frequency to discern damage in materials. The method is termed Nonlinear Wave Modulation Spectroscopy (NWMS). It con… more
Date: April 1999
Creator: Johnson, Paul A.; Sutin, Alexander & Van Den Abeele, Koen E.-A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The application of the symmetry properties of optical second harmonic generation to studies of interfaces and gases

Description: Optical second harmonic generation has proven to be a powerful tool for studying interfaces. The symmetry properties of the process allow for surface sensitivity not available with other optical methods. In this thesis, we take advantage of these symmetry properties SHG to study a variety of interesting systems not previously studied with this technique. We show that optical second harmonic generation is an effective surface probe with a submonolayer sensitivity for media without inversion symm… more
Date: November 1, 1991
Creator: Feller, M. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The application of the symmetry properties of optical second harmonic generation to studies of interfaces and gases

Description: Optical second harmonic generation has proven to be a powerful tool for studying interfaces. The symmetry properties of the process allow for surface sensitivity not available with other optical methods. In this thesis, we take advantage of these symmetry properties SHG to study a variety of interesting systems not previously studied with this technique. We show that optical second harmonic generation is an effective surface probe with a submonolayer sensitivity for media without inversion symm… more
Date: November 1, 1991
Creator: Feller, M. B.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Applications of high average power nonlinear optics

Description: Nonlinear optical frequency convertors (harmonic generators and optical parametric oscillators are reviewed with an emphasis on high average power performance and limitations. NLO materials issues and NLO device designs are discussed in reference to several emerging scientific, military and industrial commercial applications requiring {approx} 100 watt average power level in the visible and infrared spectral regions. Research efforts required to enable practical {approx} 100 watt class NLO base… more
Date: February 5, 1996
Creator: Velsko, S. P. & Krupke, W. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Articles including thin film monolayers and multilayers

Description: This invention pertains to thin film assemblies or devices useful as sensors, nonlinear optical materials, and trace material scavengers. It claims a base substrate having an oxide surface layer, and a multidentate ligand, capable of binding a metal ion, attached to the oxide surface layer of the base substrate. A metal species may be provided attached to the ligand, and a multifunctional organic ligand may be provided attached to the metal species. A second metal species may be provided attach… more
Date: December 31, 1992
Creator: Li, DeQuan & Swanson, B. I.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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Artificially structured nonlinear optical and electro-optic materials

Description: This is the final report of a 3-year project. Emerging electro-optic technologies, including optical signal processing, switching, and data manipulation, require high performance, processable nonlinear optical (NLO) and electro-optic (EO) materials. Aim of this project is to combine physical characterization and materials modelling to guide a rational synthesis of artifically structured materials optimized for NLO and EO applications. New materials consisting of chromophores optimized for the r… more
Date: April 1, 1996
Creator: Donohoe, R.; Bishop, A.; Buscher, C.; Gammel, J.; Li, Dequan; McBranch, D. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Atomic physics in strong fields

Description: This report discusses: Microwave Driven Multiphoton Excitation Dynamics in Rydberg Atoms; Nonadiabatic Geometric Phases of Multiphoton Transitions in Dissipative Systems and Spin-j Systems; and Nonperturbative Treatments of Atomic and Molecular Processes in Intense Laser Fields.
Date: April 1, 1992
Creator: Chu, Shih-I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Atomic physics in strong fields. Progress report

Description: This report discusses: Microwave Driven Multiphoton Excitation Dynamics in Rydberg Atoms; Nonadiabatic Geometric Phases of Multiphoton Transitions in Dissipative Systems and Spin-j Systems; and Nonperturbative Treatments of Atomic and Molecular Processes in Intense Laser Fields.
Date: April 1, 1992
Creator: Chu, Shih-I
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Basic Considerations on Surface Optical Nonlinearities

Description: The origins of the surface nonlinearity in surface second harmonic generation are discussed. It is shown that this second-order nonlinear optical process is characterized by a surface nonlinear susceptibility tensor containing both local and nonlocal contributions.
Date: January 1, 1986
Creator: Guyot-Sionnest, P.; Chen, W. & Shen, Y.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Beam Conditioning and Harmonic Generation in Free ElectronLasers

Description: The next generation of large-scale free-electron lasers (FELs) such as Euro-XFEL and LCLS are to be devices which produce coherent X-rays using Self-Amplified Spontaneous Emission (SASE). The performance of these devices is limited by the spread in longitudinal velocities of the beam. In the case where this spread arises primarily from large transverse oscillation amplitudes, beam conditioning can significantly enhance FEL performance. Future X-ray sources may also exploit harmonic generation s… more
Date: July 5, 2004
Creator: Charman, A.E.; Penn, G.; Wolski, A. & Wurtele, J.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Beam Echo Effect for Generation of Short-Wavelength Radiation

Description: The Echo-Enabled Harmonic Generation (EEHG) FEL uses two modulators in combination with two dispersion sections to generate a high-harmonic density modulation starting with a relatively small initial energy modulation of the beam. After presenting the concept of the EEHG, we address several practically important issues, such as the effect of coherent and incoherent synchrotron radiation in the dispersion sections. Using a representative realistic set of beam parameters, we show how the EEHG sch… more
Date: December 9, 2009
Creator: Stupakov, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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BNL Sources Development Laboratory

Description: The NSLS has a long-standing interest in providing the best possible synchrotron radiation sources for its user community, and hence, has recently established the Source Development Laboratory (SDL) to pursue research into fourth generation synchrotron radiation sources. A major element of the program includes development of a high peak power FEL meant to operate in the vacuum ultraviolet. The objective of the program is to develop the source, and experimental technology together to provide the… more
Date: January 1997
Creator: Ben-Zvi, Ilan; Graves, W.; Heese, R.; Johnson, E. D.; Krinsky, S. & Yu, L. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calculations of strong field multiphoton processes in alkali metal atoms

Description: The development of a new class of laser systems: capable of producing intense radiation in the mid-infrared (MIR) regime (photon energies between 0.3 and 0.4 eV), opens the possibility of observing multiphoton processes in a new class of systems with lower ionization potentials than those previously studied. Of particular interest are the alkali metal atoms, which are true one-(valence)-electron systems. We present theoretical calculations of above threshold ionization (ATI) and high harmonic g… more
Date: March 15, 2000
Creator: Schafer, K. J.; Gaarde, M. B.; Kulander, K. C.; Sheehy, B. & DiMauro, L. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CAVE: the design of a precision metrology instrument for studying performance of KDP crystals

Description: A device has been developed to measure the frequency conversion performance of large aperture potassium dihydrogen phosphate (KDP) crystals. Third harmonic generation using ICDP is critical to the function of the National Ignition Facility (NIF) laser. The crystals in the converter can be angularly or thermally tuned but are subject to larger aperture inhomogeneities that are functions of growth manufacturing and - mounting. The CAVE (Crystal Alignment Verification Equipment) instrument scans t… more
Date: March 30, 1998
Creator: Hibbard, R.L., LLNL
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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[Charge generation and separation at liquid interfaces]

Description: The research is divided into 3 parts: (1)Sum Frequency Generation (SFG) and Monolayer Structure. Picosecond lasers are combined by difference frequency mixing in a nonlinear crystal to generate picosecond, tunable IR pulses, which are used to study orientation of C[double bond]N and CD[sub 3] chromosphores (head group and tail) on lipid monolayers CD[sub 3](CH[sub 2])[sub 21]CN at air/water interface. (2)Femtosecond Dynamics. The femtosecond colliding pulse mode locked laser is being modified t… more
Date: January 1, 1992
Creator: Eisenthal, K.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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