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Sample records for ultrafast physics molecular

  1. Precise and ultrafast molecular sieving through graphene oxide membranes

    E-Print Network [OSTI]

    Joshi, R K; Wang, F C; Kravets, V G; Su, Y; Grigorieva, I V; Wu, H A; Geim, A K; Nair, R R

    2014-01-01

    There has been intense interest in filtration and separation properties of graphene-based materials that can have well-defined nanometer pores and exhibit low frictional water flow inside them. Here we investigate molecular permeation through graphene oxide laminates. They are vacuum-tight in the dry state but, if immersed in water, act as molecular sieves blocking all solutes with hydrated radii larger than 4.5A. Smaller ions permeate through the membranes with little impedance, many orders of magnitude faster than the diffusion mechanism can account for. We explain this behavior by a network of nanocapillaries that open up in the hydrated state and accept only species that fit in. The ultrafast separation of small salts is attributed to an 'ion sponge' effect that results in highly concentrated salt solutions inside graphene capillaries.

  2. Precise and ultrafast molecular sieving through graphene oxide membranes

    E-Print Network [OSTI]

    R. K. Joshi; P. Carbone; F. C. Wang; V. G. Kravets; Y. Su; I. V. Grigorieva; H. A. Wu; A. K. Geim; R. R. Nair

    2014-01-14

    There has been intense interest in filtration and separation properties of graphene-based materials that can have well-defined nanometer pores and exhibit low frictional water flow inside them. Here we investigate molecular permeation through graphene oxide laminates. They are vacuum-tight in the dry state but, if immersed in water, act as molecular sieves blocking all solutes with hydrated radii larger than 4.5A. Smaller ions permeate through the membranes with little impedance, many orders of magnitude faster than the diffusion mechanism can account for. We explain this behavior by a network of nanocapillaries that open up in the hydrated state and accept only species that fit in. The ultrafast separation of small salts is attributed to an 'ion sponge' effect that results in highly concentrated salt solutions inside graphene capillaries.

  3. Hydrogen Bond Migration between Molecular Sites Observed with Ultrafast 2D IR Chemical Exchange Spectroscopy

    E-Print Network [OSTI]

    Fayer, Michael D.

    Hydrogen Bond Migration between Molecular Sites Observed with Ultrafast 2D IR Chemical ExchangeVed: January 12, 2010 Hydrogen-bonded complexes between phenol and phenylacetylene are studied using ultrafast hydrogen bonding acceptor sites (phenyl or acetylene) that compete for hydrogen bond donors in solution

  4. Solvent-Dependent Molecular Structure of Ionic Species Directly Measured by Ultrafast X-Ray Solution Scattering

    E-Print Network [OSTI]

    Ihee, Hyotcherl

    Solvent-Dependent Molecular Structure of Ionic Species Directly Measured by Ultrafast X often play important roles in chemical reactions occurring in water and other solvents, but it has been elusive to determine the solvent-dependent molecular structure with atomic resolution. The triiodide ion

  5. Ultrafast Laser Spectroscopyof Chemical Reactions

    E-Print Network [OSTI]

    Zewail, Ahmed

    Ultrafast Laser Spectroscopyof Chemical Reactions - Joseph L. Kneeand AhmedH. Zewail California of chemical physics is to understand how chemi- cal reactions complete their journey from reactants to prod at the molecular level. The making of new bonds (and the breaking of old ones) in elementary chemical reactions

  6. QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS...

    Office of Scientific and Technical Information (OSTI)

    of model atoms in fields Milonni, P.W. 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; OPTICAL MODELS; QUANTUM MECHANICS;...

  7. Semiclassical molecular dynamics simulations of ultrafast photodissociation dynamics associated with the Chappuis band of ozone

    SciTech Connect (OSTI)

    Batista, V.S.; Miller, W.H. [Department of Chemistry, University of California, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Department of Chemistry, University of California, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    1998-01-01

    In this paper we investigate the nonadiabatic ultrafast dynamics of interconversion between the two lower lying excited states of {sup 1}A{sup {double_prime}} symmetry (1 {sup 1}A{sup {double_prime}} and 2 {sup 1}A{sup {double_prime}}) of ozone following photoexcitation of the molecule in the gas phase with visible light. Our algorithm involves a semiclassical initial value representation method which is able to describe electronically nonadiabatic processes within the time dependent picture through the quantization of the classical electron{endash}nuclear model Hamiltonian of Meyer and Miller [J. Chem. Phys. {bold 70}, 7 (1979)]. We explore the capabilities of these techniques as applied to studying the dynamics of a realistic reaction of photodissociation on full {ital ab initio} electronic potential energy surfaces. Our semiclassical results provide an intuitive understanding of the most fundamental dynamical features involved in the process of predissociation, such as decay and recurrence events, as well as an interpretation of experimental studies of the Chappuis band of ozone in the frequency domain. {copyright} {ital 1998 American Institute of Physics.}

  8. Laser Field Alignment of Organic Molecules on Semiconductor Surfaces: Toward Ultrafast Molecular Switches

    E-Print Network [OSTI]

    Seideman, Tamar

    tip allow operation at low intensities. The principles of nonadiabatic alignment lead to switch and molecular electronics to coherently manipulate electric current in the nanoscale is interesting not only by a molecular bond or by the molecule-surface bond. Rather, it is absorbed by the substrate, generating hot

  9. Ultrafast electron transfer at organic semiconductor interfaces: Importance of molecular orientation

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ayzner, Alexander L.; Nordlund, Dennis; Kim, Do -Hwan; Bao, Zhenan; Toney, Michael F.

    2014-12-04

    Much is known about the rate of photoexcited charge generation in at organic donor/acceptor (D/A) heterojunctions overaged over all relative arrangements. However, there has been very little experimental work investigating how the photoexcited electron transfer (ET) rate depends on the precise relative molecular orientation between D and A in thin solid films. This is the question that we address in this work. We find that the ET rate depends strongly on the relative molecular arrangement: The interface where the model donor compound copper phthalocyanine is oriented face-on with respect to the fullerene C60 acceptor yields a rate that is approximatelymore »4 times faster than that of the edge-on oriented interface. Our results suggest that the D/A electronic coupling is significantly enhanced in the face-on case, which agrees well with theoretical predictions, underscoring the importance of controlling the relative interfacial molecular orientation.« less

  10. Ultrafast electron transfer at organic semiconductor interfaces: Importance of molecular orientation

    SciTech Connect (OSTI)

    Ayzner, Alexander L.; Nordlund, Dennis; Kim, Do -Hwan; Bao, Zhenan; Toney, Michael F.

    2014-12-04

    Much is known about the rate of photoexcited charge generation in at organic donor/acceptor (D/A) heterojunctions overaged over all relative arrangements. However, there has been very little experimental work investigating how the photoexcited electron transfer (ET) rate depends on the precise relative molecular orientation between D and A in thin solid films. This is the question that we address in this work. We find that the ET rate depends strongly on the relative molecular arrangement: The interface where the model donor compound copper phthalocyanine is oriented face-on with respect to the fullerene C60 acceptor yields a rate that is approximately 4 times faster than that of the edge-on oriented interface. Our results suggest that the D/A electronic coupling is significantly enhanced in the face-on case, which agrees well with theoretical predictions, underscoring the importance of controlling the relative interfacial molecular orientation.

  11. PARTICLE ACCELERATORS; 74 ATOMIC AND MOLECULAR PHYSICS; ATOMS...

    Office of Scientific and Technical Information (OSTI)

    74 ATOMIC AND MOLECULAR PHYSICS; ATOMS; ELECTRONS; HELIUM; LIGHT SOURCES; RADIATIONS; STORAGE RINGS; SYNCHROTRONS SYNCHROTRON RADIATION SYNCHROTRONLIGHT SOURCES QUANTUM CHAOS...

  12. CYBERNETICAL PHYSICS AND CONTROL OF MOLECULAR SYSTEMS1

    E-Print Network [OSTI]

    1 CYBERNETICAL PHYSICS AND CONTROL OF MOLECULAR SYSTEMS1 Alexander Fradkov, Mikhail Ananyevsky. INTRODUCTION. PHYSICS AND CYBERNETICS Looking into the past. Encyclopedias define physics as the science studying the Nature, specifically its basic and most universal properties. The age of physics is about two

  13. School of Physics & Astronomy Physics Seminar

    E-Print Network [OSTI]

    Richmond, Michael W.

    : The progress in quantum optics utilizes a unique photon state configuration for engineering of the ultimate by progress in ultrafast optical technology provides a unique tool for probing complex molecules and nonlinear optics, atomic, molecular physics, quantum electronics, many-body theory, photovoltaics

  14. MOLECULAR BIOLOGY AND BIOCHEMISTRY Introduction to Physical Biochemistry

    E-Print Network [OSTI]

    MOLECULAR BIOLOGY AND BIOCHEMISTRY MBB 323-3 Introduction to Physical Biochemistry DAY Fall 2007 theories of physics and chemistry, called thermodynamics, kinetics, and statistical mechanics, form for measuring physical properties of biological molecules are discussed, along with the models which

  15. Ultrafast X-Ray Coherent Control

    SciTech Connect (OSTI)

    Reis, David

    2009-05-01

    This main purpose of this grant was to develop the nascent #12;eld of ultrafast x-ray science using accelerator-based sources, and originally developed from an idea that a laser could modulate the di#11;racting properties of a x-ray di#11;racting crystal on a fast enough time scale to switch out in time a shorter slice from the already short x-ray pulses from a synchrotron. The research was carried out primarily at the Advanced Photon Source (APS) sector 7 at Argonne National Laboratory and the Sub-Picosecond Pulse Source (SPPS) at SLAC; in anticipation of the Linac Coherent Light Source (LCLS) x-ray free electron laser that became operational in 2009 at SLAC (all National User Facilities operated by BES). The research centered on the generation, control and measurement of atomic-scale dynamics in atomic, molecular optical and condensed matter systems with temporal and spatial resolution . It helped develop the ultrafast physics, techniques and scienti#12;c case for using the unprecedented characteristics of the LCLS. The project has been very successful with results have been disseminated widely and in top journals, have been well cited in the #12;eld, and have laid the foundation for many experiments being performed on the LCLS, the world's #12;rst hard x-ray free electron laser.

  16. Physics with fast molecular-ion beams

    SciTech Connect (OSTI)

    Kanter, E.P.

    1980-01-01

    Fast (MeV) molecular-ion beams provide a unique source of energetic projectile nuclei which are correlated in space and time. The recognition of this property has prompted several recent investigations of various aspects of the interactions of these ions with matter. High-resolution measurements on the fragments resulting from these interactions have already yielded a wealth of new information on such diverse topics as plasma oscillations in solids and stereochemical structures of molecular ions as well as a variety of atomic collision phenomena. The general features of several such experiments will be discussed and recent results will be presented.

  17. Ultrafast studies of solution dynamics

    SciTech Connect (OSTI)

    Woodruff, W.H.; Dyer, R.B.; Callender, R.H.

    1997-10-01

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Fast chemical dynamics generally must be initiated photochemically. This limits the applicability of modern laser methods for following the structural changes that occur during chemical and biological reactions to those systems that have an electronic chromophore that has a significant yield of photoproduct when excited. This project has developed a new and entirely general approach to ultrafast initiation of reactions in solution: laser-induced temperature jump (T-jump). The results open entire new fields of study of ultrafast molecular dynamics in solution. The authors have demonstrated the T-jump technique on time scales of 50 ps and longer, and have applied it to study of the fast events in protein folding. They find that a general lifetime of alpha-helix formation is ca 100 ns, and that tertiary folds (in apomyoglobin) form in ca 100 {mu}s.

  18. PHYSICS OF CHEMORECEPTION HOWARD C. BERG AND EDWARD M. PURCELL, Department ofMolecular,

    E-Print Network [OSTI]

    Voigt, Chris

    PHYSICS OF CHEMORECEPTION HOWARD C. BERG AND EDWARD M. PURCELL, Department ofMolecular, Cellular, and Developmental Biology, University ofColorado, Boulder, Colorado 80309 and the Department ofPhysics, Harvard. In these circumstances, what are the physical limitations on the cell's ability to sense and respond to changes in its

  19. Ultrafast Transformations in Superionic Nanocrystals

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafastUltrafastUltrafastUltrafast

  20. Hue Sun Chan Departments of Biochemistry, of Molecular Genetics, and of Physics

    E-Print Network [OSTI]

    Chan, Hue Sun

    Hue Sun Chan Departments of Biochemistry, of Molecular Genetics, and of Physics University. --Hue Sun Chan, University of Toronto #12;Experimental criteria from: calorimetry: HvH/Hcal 1 chevron

  1. Molecular physics and chemistry applications of quantum Monte Carlo

    SciTech Connect (OSTI)

    Reynolds, P.J.; Barnett, R.N.; Hammond, B.L.; Lester, W.A. Jr.

    1985-09-01

    We discuss recent work with the diffusion quantum Monte Carlo (QMC) method in its application to molecular systems. The formal correspondence of the imaginary time Schroedinger equation to a diffusion equation allows one to calculate quantum mechanical expectation values as Monte Carlo averages over an ensemble of random walks. We report work on atomic and molecular total energies, as well as properties including electron affinities, binding energies, reaction barriers, and moments of the electronic charge distribution. A brief discussion is given on how standard QMC must be modified for calculating properties. Calculated energies and properties are presented for a number of molecular systems, including He, F, F , H2, N, and N2. Recent progress in extending the basic QMC approach to the calculation of ''analytic'' (as opposed to finite-difference) derivatives of the energy is presented, together with an H2 potential-energy curve obtained using analytic derivatives. 39 refs., 1 fig., 2 tabs.

  2. Diffusion-based Physical Channel Identification in Molecular Nanonetworks

    E-Print Network [OSTI]

    Politècnica de Catalunya, Universitat

    -based coding techniques are compared in terms of available bandwidth, ISI and energy consumption research area with potential applications in the biomedical, environ- mental and industrial field [1 to the communication range. For short distances, (nm-µm), molecular motors [2] and calcium signaling have been proposed

  3. Diffusion-based Physical Channel Identification in Molecular Nanonetworks

    E-Print Network [OSTI]

    Politècnica de Catalunya, Universitat

    are also compared through N3Sim in terms of available bandwidth, ISI and energy consumption applications in the biomedical, environ- mental and industrial field [1]. A nanomachine is the most basic distances, (nm-µm), molecular motors [2] and calcium signaling have been proposed [3, 4]; for the medium

  4. The Physics of Molecular CARLOS BUSTAMANTE,*, DAVID KELLER, AND

    E-Print Network [OSTI]

    Oster, George

    on the Internet at http://pubs.acs.org/accounts. ABSTRACT Molecular motors convert chemical energy into mechanical still thought of as microscopic reac- tion vessels containing complex chemical mixtures held at constant second-order chemical reactions brought about by the diffusion and random collisions of chemical species

  5. Tensor-optimized antisymmetrized molecular dynamics in nuclear physics

    E-Print Network [OSTI]

    Myo, Takayuki; Ikeda, Kiyomi; Horiuchi, Hisashi; Suhara, Tadahiro

    2015-01-01

    We develop a new formalism to treat nuclear many-body systems using bare nucleon-nucleon interaction. It has become evident that the tensor interaction plays important role in nuclear many-body systems due to the role of the pion in strongly interacting system. We take the antisymmetrized molecular dynamics (AMD) as a basic framework and add a tensor correlation operator acting on the AMD wave function using the concept of the tensor-optimized shell model (TOSM). We demonstrate a systematical and straightforward formulation utilizing the Gaussian integration and differentiation method and the antisymmetrization technique to calculate all the matrix elements of the many-body Hamiltonian. We can include the three-body interaction naturally and calculate the matrix elements systematically in the progressive order of the tensor correlation operator. We call the new formalism "tensor-optimized antisymmetrized molecular dynamics".

  6. Ultrafast Probes for Dirac Materials Yarotski, Dmitry Anatolievitch...

    Office of Scientific and Technical Information (OSTI)

    Science(36) Material Science; topological insulators, ultrafast spectroscopy, graphene Material Science; topological insulators, ultrafast spectroscopy, graphene Abstract...

  7. Ultrafast Transformations in Superionic Nanocrystals

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafastUltrafastUltrafast

  8. Ultrafast scanning tunneling microscopy

    SciTech Connect (OSTI)

    Botkin, D.A. [California Univ., Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley Lab., CA (United States)

    1995-09-01

    I have developed an ultrafast scanning tunneling microscope (USTM) based on uniting stroboscopic methods of ultrafast optics and scanned probe microscopy to obtain nanometer spatial resolution and sub-picosecond temporal resolution. USTM increases the achievable time resolution of a STM by more than 6 orders of magnitude; this should enable exploration of mesoscopic and nanometer size systems on time scales corresponding to the period or decay of fundamental excitations. USTM consists of a photoconductive switch with subpicosecond response time in series with the tip of a STM. An optical pulse from a modelocked laser activates the switch to create a gate for the tunneling current, while a second laser pulse on the sample initiates a dynamic process which affects the tunneling current. By sending a large sequence of identical pulse pairs and measuring the average tunnel current as a function of the relative time delay between the pulses in each pair, one can map the time evolution of the surface process. USTM was used to measure the broadband response of the STM`s atomic size tunnel barrier in frequencies from tens to hundreds of GHz. The USTM signal amplitude decays linearly with the tunnel junction conductance, so the spatial resolution of the time-resolved signal is comparable to that of a conventional STM. Geometrical capacitance of the junction does not appear to play an important role in the measurement, but a capacitive effect intimately related to tunneling contributes to the measured signals and may limit the ultimate resolution of the USTM.

  9. MOLECULAR PHYSICS, 2002, VOL. 100, NO. 11, 16591675 Key properties of monohalogen substituted phenols: interpretation

    E-Print Network [OSTI]

    Nguyen, Minh Tho

    MOLECULAR PHYSICS, 2002, VOL. 100, NO. 11, 1659±1675 Key properties of monohalogen substituted August 2001; accepted 31 December 2001) This paper is an attempt to bridge the key properties by Runge from coal tar [1] in 1834 and named pheÂnol by Gerhardt in 1843 [2] (see also Laurent [3

  10. PHYSICAL REVIEW A 91, 053410 (2015) Dipole and nondipole photoionization of molecular hydrogen

    E-Print Network [OSTI]

    Winfree, Erik

    2015-01-01

    PHYSICAL REVIEW A 91, 053410 (2015) Dipole and nondipole photoionization of molecular hydrogen B. The theoretical formalism is presented and applied to photoionization of H2 over the 20- to 180-eV photon energy and large kinetic energies, and nondipole asymmetries were * Present address: Wolfram Research, Champaign

  11. MOLECULAR PHYSICS, 1999, VOL. 97, NO. 7, 897 905 Dynamics and hydrogen bonding in liquid ethanol

    E-Print Network [OSTI]

    Saiz, Leonor

    MOLECULAR PHYSICS, 1999, VOL. 97, NO. 7, 897± 905 Dynamics and hydrogen bonding in liquid ethanol L of liquid ethanol at three temperatures have been carried out. The hydrogen bonding states of ethanol measurements of the frequency-dependent dielectric permittivity of liquid ethanol. 1. Introduction A detailed

  12. Ultrafast Transformations in Superionic Nanocrystals

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal designUltrafast Transformations in SuperionicUltrafast

  13. Ultrafast Surface Plasmonic Switch in Non-Plasmonic Metals

    E-Print Network [OSTI]

    Bévillon, E; Recoules, V; Zhang, H; Li, C; Stoian, R

    2015-01-01

    We demonstrate that ultrafast carrier excitation can drastically affect electronic structures and induce brief surface plasmonic response in non-plasmonic metals, potentially creating a plasmonic switch. Using first-principles molecular dynamics and Kubo-Greenwood formalism for laser-excited tungsten we show that carrier heating mobilizes d electrons into collective inter and intraband transitions leading to a sign flip in the imaginary optical conductivity, activating plasmonic properties for the initial non-plasmonic phase. The drive for the optical evolution can be visualized as an increasingly damped quasi-resonance at visible frequencies for pumping carriers across a chemical potential located in a d-band pseudo-gap with energy-dependent degree of occupation. The subsequent evolution of optical indices for the excited material is confirmed by time-resolved ultrafast ellipsometry. The large optical tunability extends the existence spectral domain of surface plasmons in ranges typically claimed in laser se...

  14. New Algorithm Enables Fast Simulations of Ultrafast Processes

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    real-time simulations of ultrafast processes and electron dynamics, such as excitation in photovoltaic materials and ultrafast demagnetization following an optical excitation. "We...

  15. Ultrafast Laser Diagnostics to Investigate Initiation in Energetic...

    Office of Scientific and Technical Information (OSTI)

    Ultrafast Laser Diagnostics to Investigate Initiation in Energetic Materials. Citation Details In-Document Search Title: Ultrafast Laser Diagnostics to Investigate Initiation in...

  16. Surface modified CFx cathode material for ultrafast discharge...

    Office of Scientific and Technical Information (OSTI)

    Surface modified CFx cathode material for ultrafast discharge and high energy density Citation Details In-Document Search Title: Surface modified CFx cathode material for ultrafast...

  17. Surface modified CFx cathode material for ultrafast discharge...

    Office of Scientific and Technical Information (OSTI)

    Surface modified CFx cathode material for ultrafast discharge and high energy density Prev Next Title: Surface modified CFx cathode material for ultrafast discharge and high...

  18. Physical aspects of the structure and function of helicases as rotary molecular motors

    SciTech Connect (OSTI)

    Pikin, S. A.

    2009-11-15

    Helicases were shown to have common physical properties with rotary molecular motors, such as F{sub 0}F{sub 1}-ATP synthase and type I restriction-modification (RM) enzymes. The necessary conditions for action of molecular motors are chirality, the presence of the C{sub 2} (or lower) symmetry axis within rather large atomic groups, and polarization properties. The estimates were made for the material parameters of helicases, which translocate DNA due to moving chiral kinks without DNA cleavage and are characterized by higher viscosity, low mobility, and smaller chiral kinetic coefficients than type II RM enzymes. This paper discusses the efficiency of helicases with opposite polarities that drive DNA translocation in opposite directions.

  19. Ultrafast Diagnostics for Electron Beams from Laser Plasma Accelerators

    E-Print Network [OSTI]

    Matlis, N. H.

    2011-01-01

    Ultrafast Diagnostics for Electron Beams from Laser Plasmadiagnostic techniques [2]. While the field of electron beam

  20. Generation of mega-electron-volt electron beams by an ultrafast intense laser pulse

    E-Print Network [OSTI]

    Umstadter, Donald

    Generation of mega-electron-volt electron beams by an ultrafast intense laser pulse Xiaofang Wang filamentation and beam breakup. These results suggest an approach for generating a beam of femtosecond, Me-intensity lasers has made it pos- sible to study extreme physics on a tabletop. Among the studies, the generation

  1. Ultrafast Transformations in Superionic Nanocrystals

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0 - 19 Publications 1.Design » DesignUltrafast

  2. Ultrafast Transformations in Superionic Nanocrystals

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal designUltrafast Transformations in Superionic

  3. Ultrafast Spectroscopy of Warm Dense Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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  4. Two physical regimes for the Giant HII Regions and Giant Molecular Clouds in the Antennae Galaxies

    E-Print Network [OSTI]

    Zaragoza-Cardiel, Javier; Beckman, John E; García-Lorenzo, Begoña; Erroz-Ferrer, Santiago; Gutiérrez, Leonel

    2014-01-01

    We have combined observations of the Antennae galaxies from the radio interferometer ALMA (Atacama Large Millimetre/submillimetre Array) and from the optical interferometer GH$\\alpha$FaS (Galaxy Halpha Fabry-Perot System). The two sets of observations have comparable angular and spectral resolutions, enabling us to identify 142 giant molecular clouds and 303 HII regions. We have measured, and compare, their basic physical properties (radius, velocity dispersion, luminosity). For the HII regions we find two physical regimes, one for masses $>10^{5.4} \\mathrm{M_{\\odot}}$ of ionized gas, which the gas density increases with gas mass, the other for masses $<10^{5.4} \\mathrm{M_{\\odot}}$ of ionized gas where the gas density decreases with gas mass. For the GMCs we find, in contrast to previous studies in other galaxies over a generally lower mass range of clouds, that the gas density increases with the total gas mass, hinting at two regimes for these clouds if we consider both sources of data. We also find that ...

  5. THE JOURNAL OF CHEMICAL PHYSICS 140, 144702 (2014) Theory of third-order spectroscopic methods to extract detailed molecular

    E-Print Network [OSTI]

    Fayer, Michael D.

    2014-01-01

    THE JOURNAL OF CHEMICAL PHYSICS 140, 144702 (2014) Theory of third-order spectroscopic methods to extract detailed molecular orientational dynamics for planar surfaces and other uniaxial systems Jun) experiments. In this article we provide a model-independent theory to extract orientational correlation

  6. THE JOURNAL OF CHEMICAL PHYSICS 138, 244310 (2013) Molecular dynamics simulations for CO2 spectra. IV. Collisional line-mixing

    E-Print Network [OSTI]

    Boyer, Edmond

    2013-01-01

    atmosphere of Venus (about 96.5% of CO2) where the pressure is high (up to 90 bar). Similarly, narrow involving CO2 with a few for the pure gas in the infrared at high pressure12­17 and Raman Q branches.4THE JOURNAL OF CHEMICAL PHYSICS 138, 244310 (2013) Molecular dynamics simulations for CO2 spectra

  7. An ultrafast carbon nanotube terahertz polarisation modulator

    SciTech Connect (OSTI)

    Docherty, Callum J.; Stranks, Samuel D.; Habisreutinger, Severin N.; Joyce, Hannah J.; Herz, Laura M.; Nicholas, Robin J.; Johnston, Michael B., E-mail: m.johnston@physics.ox.ac.uk [Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU (United Kingdom)

    2014-05-28

    We demonstrate ultrafast modulation of terahertz radiation by unaligned optically pumped single-walled carbon nanotubes. Photoexcitation by an ultrafast optical pump pulse induces transient terahertz absorption in nanowires aligned parallel to the optical pump. By controlling the polarisation of the optical pump, we show that terahertz polarisation and modulation can be tuned, allowing sub-picosecond modulation of terahertz radiation. Such speeds suggest potential for semiconductor nanowire devices in terahertz communication technologies.

  8. Ultrafast reaction dynamics in cluster ions: Simulation of the transient photoelectron spectrum of I2 Arn photodissociation

    E-Print Network [OSTI]

    Faeder, Jim

    Hamiltonian model of electronic structure with nonadiabatic molecular dynamics simulations, we calculate of the electronic structure of a manifold of states strongly coupled to the many solvent degrees of freedomUltrafast reaction dynamics in cluster ions: Simulation of the transient photoelectron spectrum

  9. Ultrafast dynamic ellipsometry of laser driven shock waves

    E-Print Network [OSTI]

    Bolme, Cynthia Anne

    2008-01-01

    The experimental measurement technique of ultrafast dynamic ellipsometry (UDE) was developed for measuring material motion and changes in optical properties of samples under laser driven shock loading. Ultrafast dynamic ...

  10. Multibounce light transport analysis using ultrafast imaging for material acquisition

    E-Print Network [OSTI]

    Naik, Nikhil, S.M. Massachusetts Institute of Technology

    2012-01-01

    This thesis introduces a novel framework for analysis of multibounce light transport using time-of-flight imaging for the applications of ultrafast reflectance acquisition and imaging through scattering media. Using ultrafast ...

  11. Applied Statistical Physics Molecular Engineering Conference Puerto Vallarta, Mexico, 24-29 August 2003

    E-Print Network [OSTI]

    Barbosa, Marcia C. B.

    , Molecular Design of New Catalysts and Nanoporous Materials by Assembling & Combinatorial Methods-circuits and nano-biotechnology, with self-assembly of supramolecular materials and molecular confinement, Petroleomics: From Petroleum Composition to Commercial Realty, Materials Characterization Techniques

  12. The Physical Conditions in a Pre Super Star Cluster Molecular Cloud in the Antennae Galaxies

    E-Print Network [OSTI]

    Johnson, K E; Indebetouw, R; Brogan, C L; Whitmore, B C; Hibbard, J; Sheth, K; Evans, A

    2015-01-01

    We present an analysis of the physical conditions in an extreme molecular cloud in the Antennae merging galaxies. This cloud has properties consistant with those required to form a globular cluster. We have obtained ALMA CO and 870$\\mu$m observations of the Antennae galaxy system with $\\sim 0".5$ resolution. This cloud stands out in the data with a radius of $\\lesssim 24$~pc and mass of $>5\\times 10^6$~M$_\\odot$. The cloud appears capable of forming a globular cluster, but the lack of associated thermal radio emission indicates that star formation has not yet altered the environment. The lack of thermal radio emission places the cloud in an early stage of evolution, which we expect to be short-lived ($\\lesssim 1$~Myr) and thus rare. Given its mass and kinetic energy, for the cloud to be confined (as its appearance strongly suggests) it must be subject to an external pressure of P/$k_B \\gtrsim 10^8$~K~cm$^{-3}$ -- 10,000 times higher than typical interstellar pressure. This would support theories that high pre...

  13. UPGRADING METHANE USING ULTRA-FAST THERMAL SWING ADSORPTION

    SciTech Connect (OSTI)

    Anna Lee Tonkovich

    2004-01-01

    The purpose of this project is to design and demonstrate an approach to upgrade low-BTU methane streams from coal mines to pipeline-quality natural gas. The objective of Phase I of the project was to assess the feasibility of upgrading low-Btu methane streams using ultra-fast thermal swing adsorption (TSA) using Velocys' modular microchannel process technology. The project is on schedule and under budget. For Task 1.1, the open literature, patent information, and vendor contacts were surveyed to identify adsorbent candidates for experimental validation and subsequent demonstration in an MPT-based ultra-fast TSA separation for methane upgrading. The leading candidates for preferential adsorption of methane over nitrogen are highly microporous carbons. A Molecular Gate{trademark} zeolite from Engelhard Corporation has emerged as a candidate. For Task 1.2, experimental evaluation of adsorbents was initiated, and data were collected on carbon (MGN-101) from PICA, Inc. This carbon demonstrated a preferential capacity for methane over nitrogen, as well as a reasonable thermal swing differential capacity for a 90% methane and 10% nitrogen mixture. A similar methane swing capacity at 2 psig was measured. The mixture composition is relevant because gob gas contains nearly 85% methane and must be purified to 97% methane for pipeline quality.

  14. Simulation-based Evaluation of the Diffusion-based Physical Channel in Molecular Nanonetworks

    E-Print Network [OSTI]

    Politècnica de Catalunya, Universitat

    in terms of available bandwidth and energy consumption for communication. I. INTRODUCTION Nanomachines, to the industrial and the biomedical [1]. Amongst other proposed techniques, molecular communi- cation enables to the communication range. For short distances (nm- µm), molecular motors [2] and calcium signaling have been proposed

  15. Ultrafast Laser Facility | Photosynthetic Antenna Research Center

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafast Core-HoleUltrafast Laser

  16. Ultrafast Spectroscopy of Warm Dense Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafastUltrafast Spectroscopy of

  17. Ultrafast Spectroscopy of Warm Dense Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafastUltrafast Spectroscopy

  18. PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Photonic RF Waveform Synthesis,

    E-Print Network [OSTI]

    Purdue University

    PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Photonic RF Waveform, Shijun Xiao Funding from ARO, DARPA, and NSF #12;PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER performance (spectral engineering, dispersion compensation) #12;PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL

  19. PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Andrew M. Weiner and Ehsan Hamidi

    E-Print Network [OSTI]

    Purdue University

    PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Andrew M. Weiner ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Ultrawideband (UWB) Radio-frequency Photonics UWB;PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORY Femtosecond Pulse Shaping A

  20. Simulation-based Evaluation of the Diffusion-based Physical Channel in Molecular Nanonetworks

    E-Print Network [OSTI]

    Politècnica de Catalunya, Universitat

    are also compared through NanoSim in terms of available bandwidth and energy consumption for communication fields, ranging from the environmental, to the industrial and the biomedical [1]. Amongst other proposed (nm- µm), molecular motors [2] and calcium signaling have been proposed [3], [4]; for the medium range

  1. MOLECULAR PHYSICS, MAY 2003, VOL. 101, NO. 9, 12591265 electronically stable?

    E-Print Network [OSTI]

    Simons, Jack

    boron and boron-based materials are among candidates for rocket fuels [10] and (ii) high energy density is not stable when rotational energies are included whereas BOHÀ is for low rotational quantum numbers. 1 of extracting energy from high energy substances is the conversion of metastable molecular configurations, which

  2. Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Group (PDG) Organizations American Institute of Physics (AIP) American Physical Society (APS) Institute of Physics (IOP) SPIE - International society for optics and photonics Top...

  3. Ultrafast kinetics subsequent to shock in an unreacted, oxygen...

    Office of Scientific and Technical Information (OSTI)

    subsequent to shock in an unreacted, oxygen balanced mixture of nitromethane and hydrogen peroxide Citation Details In-Document Search Title: Ultrafast kinetics subsequent to...

  4. Ultrafast Structural Dynamics in Combustion Relevant Model Systems

    SciTech Connect (OSTI)

    Weber, Peter M.

    2014-03-31

    The research project explored the time resolved structural dynamics of important model reaction system using an array of novel methods that were developed specifically for this purpose. They include time resolved electron diffraction, time resolved relativistic electron diffraction, and time resolved Rydberg fingerprint spectroscopy. Toward the end of the funding period, we also developed time-resolved x-ray diffraction, which uses ultrafast x-ray pulses at LCLS. Those experiments are just now blossoming, as the funding period expired. In the following, the time resolved Rydberg Fingerprint Spectroscopy is discussed in some detail, as it has been a very productive method. The binding energy of an electron in a Rydberg state, that is, the energy difference between the Rydberg level and the ground state of the molecular ion, has been found to be a uniquely powerful tool to characterize the molecular structure. To rationalize the structure sensitivity we invoke a picture from electron diffraction: when it passes the molecular ion core, the Rydberg electron experiences a phase shift compared to an electron in a hydrogen atom. This phase shift requires an adjustment of the binding energy of the electron, which is measurable. As in electron diffraction, the phase shift depends on the molecular, geometrical structure, so that a measurement of the electron binding energy can be interpreted as a measurement of the molecule’s structure. Building on this insight, we have developed a structurally sensitive spectroscopy: the molecule is first elevated to the Rydberg state, and the binding energy is then measured using photoelectron spectroscopy. The molecule’s structure is read out as the binding energy spectrum. Since the photoionization can be done with ultrafast laser pulses, the technique is inherently capable of a time resolution in the femtosecond regime. For the purpose of identifying the structures of molecules during chemical reactions, and for the analysis of molecular species in the hot environments of combustion processes, there are several features that make the Rydberg ionization spectroscopy uniquely useful. First, the Rydberg electron’s orbit is quite large and covers the entire molecule for most molecular structures of combustion interest. Secondly, the ionization does not change vibrational quantum numbers, so that even complicated and large molecules can be observed with fairly well resolved spectra. In fact, the spectroscopy is blind to vibrational excitation of the molecule. This has the interesting consequence for the study of chemical dynamics, where the molecules are invariably very energetic, that the molecular structures are observed unobstructed by the vibrational congestion that dominates other spectroscopies. This implies also that, as a tool to probe the time-dependent structural dynamics of chemically interesting molecules, Rydberg spectroscopy may well be better suited than electron or x-ray diffraction. With recent progress in calculating Rydberg binding energy spectra, we are approaching the point where the method can be evolved into a structure determination method. To implement the Rydberg ionization spectroscopy we use a molecular beam based, time-resolved pump-probe multi-photon ionization/photoelectron scheme in which a first laser pulse excites the molecule to a Rydberg state, and a probe pulse ionizes the molecule. A time-of-flight detector measures the kinetic energy spectrum of the photoelectrons. The photoelectron spectrum directly provides the binding energy of the electron, and thereby reveals the molecule’s time-dependent structural fingerprint. Only the duration of the laser pulses limits the time resolution. With a new laser system, we have now reached time resolutions better than 100 fs, although very deep UV wavelengths (down to 190 nm) have slightly longer instrument functions. The structural dynamics of molecules in Rydberg-excited states is obtained by delaying the probe ionization photon from the pump photon; the structural dynamics of molecules in their ground state or e

  5. Ultrafast Spectroscopy of Warm Dense Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafast

  6. An icing physics study by using lifetime-based molecular tagging thermometry technique

    E-Print Network [OSTI]

    Hu, Hui

    of water droplets Solidification process Micro scale heat transfer Wind turbine icing a b s t r a c to produce 20% of its total power from wind by 2030. According to American Wind Energy Association (AWEA within small icing water droplets in order to elucidate underlying physics to improve our under- standing

  7. Physics of Molecular and Biological Matter Research group Prof. Frank Schreiber

    E-Print Network [OSTI]

    Schreiber, Frank

    as a function of time and experimental control parameters such as salt concentration and temperature scattering (SLS/DLS), IR spectroscopy, Small angle X-ray and Neutron Scattering (SAXS/SANS). Contact: fajun Projects: Protein Physics Real-Time Study of Protein Crystallization Proteins play crucial functional

  8. Communication Interlaced Fourier transformation of ultrafast 2D NMR data

    E-Print Network [OSTI]

    Frydman, Lucio

    Communication Interlaced Fourier transformation of ultrafast 2D NMR data Mor Mishkovsky, Lucio in ultrafast 2D NMR is discussed and exemplified, based on the interlaced Fourier transformation. This approach in the achievable digital resolution. These expectations were tested by carrying out a series of homo

  9. Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Physics Our science answers questions about the nature of the universe and delivers solutions for national security concerns. Contact Us Division Leader Doug Fulton Deputy...

  10. The BLAST Survey of the Vela Molecular Cloud: Physical Properties of the Dense Cores in Vela-D

    E-Print Network [OSTI]

    Olmi, Luca; Angles-Alcazar, Daniel; Bock, James J; Chapin, Edward L; De Luca, Massimo; Devlin, Mark J; Dicker, Simon; Elia, Davide; Fazio, Giovanni G; Giannini, Teresa; Griffin, Matthew; Gundersen, Joshua O; Halpern, Mark; Hargrave, Peter C; Hughes, David H; Klein, Jeff; Lorenzetti, Dario; Marengo, Massimo; Marsden, Gaelen; Martin, Peter G; Massi, Fabrizio; Mauskopf, Philip; Netterfield, Calvin B; Patanchon, Guillaume; Rex, Marie; Salama, Alberto; Scott, Douglas; Semisch, Christopher; Smith, Howard A; Strafella, Francesco; Thomas, Nicholas; Truch, Matthew D P; Tucker, Carole; Tucker, Gregory S; Viero, Marco P; Wiebe, Donald V

    2009-01-01

    The Balloon-borne Large-Aperture Submillimeter Telescope (BLAST) carried out a 250, 350 and 500 micron survey of the galactic plane encompassing the Vela Molecular Ridge, with the primary goal of identifying the coldest, dense cores possibly associated with the earliest stages of star formation. Here we present the results from observations of the Vela-D region, covering about 4 square degrees, in which we find 141 BLAST cores. We exploit existing data taken with the Spitzer MIPS, IRAC and SEST-SIMBA instruments to constrain their (single-temperature) spectral energy distributions, assuming a dust emissivity index beta = 2.0. This combination of data allows us to determine the temperature, luminosity and mass of each BLAST core, and also enables us to separate starless from proto-stellar sources. We also analyze the effects that the uncertainties on the derived physical parameters of the individual sources have on the overall physical properties of starless and proto-stellar cores, and we find that there appe...

  11. Ultrafast transient reflectance of epitaxial semiconducting perovskite thin films

    SciTech Connect (OSTI)

    Smolin, S. Y.; Guglietta, G. W.; Baxter, J. B. E-mail: smay@coe.drexel.edu; Scafetta, M. D.; May, S. J. E-mail: smay@coe.drexel.edu

    2014-07-14

    Ultrafast pump-probe transient reflectance (TR) spectroscopy was used to study carrier dynamics in an epitaxial perovskite oxide thin film of LaFeO{sub 3} (LFO) with a thickness of 40 unit cells (16?nm) grown by molecular beam epitaxy on (LaAlO{sub 3}){sub 0.3}(Sr{sub 2}AlTaO{sub 6}){sub 0.7} (LSAT). TR spectroscopy shows two negative transients in reflectance with local maxima at ?2.5?eV and ?3.5?eV which correspond to two optical transitions in LFO as determined by ellipsometry. The kinetics at these transients were best fit with an exponential decay model with fast (5–40 ps), medium (?200 ps), and slow (??3?ns) components that we attribute mainly to recombination of photoexcited carriers. Moreover, these reflectance transients did not completely decay within the observable time window, indicating that ?10% of photoexcited carriers exist for at least 3?ns. This work illustrates that TR spectroscopy can be performed on thin (<20?nm) epitaxial oxide films to provide a quantitative understanding of recombination lifetimes, which are important parameters for the potential utilization of perovskite films in photovoltaic and photocatalytic applications.

  12. Resource Letter: Bio-molecular Nano-machines: where Physics, Chemistry, Biology and Technology meet

    E-Print Network [OSTI]

    Debashish Chowdhury

    2008-07-17

    Cell is the structural and functional unit of life. This Resource Letter serves as a guide to the literature on nano-machines which drive not only intracellular movements, but also motility of the cell. These machines are usually proteins or macromolecular assemblies which require appropriate fuel for their operations. Although, traditionally, these machines were subjects of investigation in biology and biochemistry, increasing use of the concepts and techniques of physics in recent years have contributed to the quantitative understanding of the fundamental principles underlying their operational mechanisms. The possibility of exploiting these principles for the design and control of artificial nano-machines has opened up a new frontier in the bottom-up approach to nano-technology.

  13. Femtosecond laser studies of ultrafast intramolecular processes

    SciTech Connect (OSTI)

    Hayden, C. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    The goal of this research is to better understand the detailed mechanisms of chemical reactions by observing, directly in time, the dynamics of fundamental chemical processes. In this work femtosecond laser pulses are used to initiate chemical processes and follow the progress of these processes in time. The authors are currently studying ultrafast internal conversion and subsequent intramolecular relaxation in unsaturated hydrocarbons. In addition, the authors are developing nonlinear optical techniques to prepare and monitor the time evolution of specific vibrational motions in ground electronic state molecules.

  14. Laser safety information for the Atomic, Molecular and Optical (AMO) Physics Labs at Lehigh University modified from the laser safety program developed by the office of Environmental

    E-Print Network [OSTI]

    Huennekens, John

    1 Laser safety information for the Atomic, Molecular and Optical (AMO) Physics Labs at Lehigh University modified from the laser safety program developed by the office of Environmental Health and Safety using the following reference materials: I. American National Standards for Safe Use of Lasers - ANSI Z

  15. Apparatus and method for characterizing ultrafast polarization varying optical pulses

    DOE Patents [OSTI]

    Smirl, Arthur (1020 Cherry La. Northwest, Iowa City, IA 52240); Trebino, Rick P. (425 Mulqueeny St., Livermore, CA 94550)

    1999-08-10

    Practical techniques are described for characterizing ultrafast potentially ultraweak, ultrashort optical pulses. The techniques are particularly suited to the measurement of signals from nonlinear optical materials characterization experiments, whose signals are generally too weak for full characterization using conventional techniques.

  16. Ultrafast Core-Hole Induced Dynamics in Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the fluorescence from an electron reoccupying the oxygen 1s core level is measured. For hydrogen-bonded systems such as liquid water, ultrafast dynamics that occur during the...

  17. Ultrafast pump-probe force microscopy with nanoscale resolution

    E-Print Network [OSTI]

    2015-01-01

    Cerullo, “Confocal ultrafast pump-probe spectroscopy: A newand H. J. Maris, “Time-resolved pump-probe experiments withand U. Keller, “Femtosecond pump-porbe near-field optical

  18. A Source for Ultrafast Continuum Infrared and Terahertz Radiation

    E-Print Network [OSTI]

    Petersen, Poul B.

    A compact and stable method for generating high-intensity linearly polarized continuum mid-IR and terahertz light using ultrafast femtosecond (fs) laser pulses is demonstrated. Continuous light generation from <400cm?1 ...

  19. Ultrafast X-ray Sources

    SciTech Connect (OSTI)

    George Neil

    2010-04-19

    Since before the scattering of X-rays off of DNA led to the first understanding of the double helix structure, sources of X-rays have been an essential tool for scientists examining the structure and interactions of matter. The resolution of a microscope is proportional to the wavelength of light so x-rays can see much finer structures than visible light, down to single atoms. In addition, the energy of X-rays is resonant with the core atomic levels of atoms so with appropriate wavelengths the placement of specific atoms in a large molecule can be determined. Over 10,000 scientists use synchrotron sources, storage rings of high energy electrons, each year worldwide. As an example of such use, virtually every picture of a protein or drug molecule that one sees in the scientific press is a reconstruction based on X-ray scattering of synchrotron light from the crystallized form of that molecule. Unfortunately those pictures are static and proteins work through configuration (shape) changes in response to energy transfer. To understand how biological systems work requires following the energy flow to these molecules and tracking how shape changes drive their interaction with other molecules. We'd like to be able to freeze the action of these molecules at various steps along the way with an X-ray strobe light. How fast does it have to be? To actually get a picture of a molecule in a fixed configuration requires X-ray pulses as short as 30 femtoseconds (1/30 of a millionth of a millionth of a second). To capture the energy flow through changes in electronic levels requires a faster strobe, less than 1 femtosecond! And to acquire such information in smaller samples with higher accuracy demands brighter and brighter X-rays. Unfortunately modern synchrotrons (dubbed 3rd Generation Light Sources) cannot deliver such short bright pulses of X-rays. An entirely new approach is required, linear-accelerator (linac-)-based light sources termed 4th or Next Generation Light Sources (NGLSs). Although NGLSs will not displace synchrotrons from their role they do offer exciting new capabilities which can be understood from the physics of the light production in each device.

  20. All-Optical Molecular Orientation

    SciTech Connect (OSTI)

    Oda, Keita; Hita, Masafumi; Minemoto, Shinichirou; Sakai, Hirofumi [Department of Physics, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2010-05-28

    We report clear evidence of all-optical orientation of carbonyl sulfide molecules with an intense nonresonant two-color laser field in the adiabatic regime. The technique relies on the combined effects of anisotropic hyperpolarizability interaction and anisotropic polarizability interaction and does not rely on the permanent dipole interaction with an electrostatic field. It is demonstrated that the molecular orientation can be controlled simply by changing the relative phase between the two wavelength fields. The present technique brings researchers a new steering tool of gaseous molecules and will be quite useful in various fields such as electronic stereodynamics in molecules and ultrafast molecular imaging.

  1. Ultrafast Optics and Optical Fiber Communications Laboratory http://purcell.ecn.purdue.edu/~fsoptics/

    E-Print Network [OSTI]

    Purdue University

    Ultrafast Optics and Optical Fiber Communications Laboratory http, A. M. Weiner Purdue University C. Lin Avanex Corporation Conference on Lasers and Electro Optics;Ultrafast Optics and Optical Fiber Communications Laboratory http://purcell.ecn.purdue.edu/~fsoptics/ 2

  2. Ultrafast optical pulse manipulation in three dimensional-resolved microscope imaging and microfabrication

    E-Print Network [OSTI]

    Kim, Daekeun, Ph. D. Massachusetts Institute of Technology

    2009-01-01

    The availability of lasers with femtosecond, ultrafast light pulses provides new opportunities and challenges in instrument design. This thesis addresses three aspects of utilizing ultrafast light pulses in two-photon ...

  3. Semiclassical molecular dynamics simulations of excited state double-proton transfer in 7-azaindole dimers

    SciTech Connect (OSTI)

    Guallar, V.; Batista, V.S.; Miller, W.H. [Department of Chemistry, University of California, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Department of Chemistry, University of California, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    1999-05-01

    An {ital ab initio} excited state potential energy surface is constructed for describing excited state double proton transfer in the tautomerization reaction of photo-excited 7-azaindole dimers, and the ultrafast dynamics is simulated using the semiclassical (SC) initial value representation (IVR). The potential energy surface, determined in a reduced dimensionality, is obtained at the CIS level of quantum chemistry, and an approximate version of the SC-IVR approach is introduced which scales {ital linearly} with the number of degrees of freedom of the molecular system. The accuracy of this approximate SC-IVR approach is verified by comparing our semiclassical results with full quantum mechanical calculations. We find that proton transfer usually occurs during the first intermonomer symmetric-stretch vibration, about 100 fs after photoexcitation of the system, and produces an initial 15 percent population decay of the reactant base-pair, which is significantly reduced by isotopic substitution. {copyright} {ital 1999 American Institute of Physics.} thinsp

  4. Fourier information optics for the ultrafast time domain Andrew M. Weiner

    E-Print Network [OSTI]

    Purdue University

    Fourier information optics for the ultrafast time domain Andrew M. Weiner School of Electrical); published 26 November 2007 Ultrafast photonic signal processing based on Fourier optics principles offers of ultrafast optical signals via conversion between time, space, and optical frequency (Fourier) domains

  5. Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid youOxygen Generation | Center for GasPhysics Physics Print Because a

  6. Ultrafast energy transfer from rigid, branched side-chains into a conjugated, alternating copolymer

    SciTech Connect (OSTI)

    Griffin, Graham B.; Rolczynski, Brian S.; Linkin, Alexander; McGillicuddy, Ryan D.; Engel, Gregory S., E-mail: gsengel@uchicago.edu [Department of Chemistry, The James Franck Institute, Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637 (United States); Lundin, Pamela M. [Department of Chemical Engineering, Stanford University, Stauffer III, 381 North-South Mall, Stanford, California 94305 (United States) [Department of Chemical Engineering, Stanford University, Stauffer III, 381 North-South Mall, Stanford, California 94305 (United States); A. R. Smith Department of Chemistry, Appalachian State University, 417 CAP Building, 525 Rivers Street, Boone, North Carolina 28608 (United States); Bao, Zhenan [Department of Chemical Engineering, Stanford University, Stauffer III, 381 North-South Mall, Stanford, California 94305 (United States)] [Department of Chemical Engineering, Stanford University, Stauffer III, 381 North-South Mall, Stanford, California 94305 (United States)

    2014-01-21

    We present the synthesis and characterization of a benzodithiophene/thiophene alternating copolymer decorated with rigid, singly branched pendant side chains. We characterize exciton migration and recombination dynamics in these molecules in tetrahydrofuran solution, using a combination of static and time-resolved spectroscopies. As control experiments, we also measure electronic relaxation dynamics in isolated molecular analogues of both the side chain and polymer moieties. We employ semi-empirical and time-dependent density functional theory calculations to show that photoexcitation of the decorated copolymer using 395 nm laser pulses results in excited states primarily localized on the pendant side chains. We use ultrafast transient absorption spectroscopy to show that excitations are transferred to the polymer backbone faster than the instrumental response function, ?250 fs.

  7. Impact system for ultrafast synchrotron experiments

    SciTech Connect (OSTI)

    Jensen, B. J.; Owens, C. T.; Ramos, K. J.; Yeager, J. D.; Saavedra, R. A.; Luo, S. N.; Hooks, D. E.; Iverson, A. J.; Fezzaa, K.

    2013-01-15

    The impact system for ultrafast synchrotron experiments, or IMPULSE, is a 12.6-mm bore light-gas gun (<1 km/s projectile velocity) designed specifically for performing dynamic compression experiments using the advanced imaging and X-ray diffraction methods available at synchrotron sources. The gun system, capable of reaching projectile velocities up to 1 km/s, was designed to be portable for quick insertion/removal in the experimental hutch at Sector 32 ID-B of the Advanced Photon Source (Argonne, IL) while allowing the target chamber to rotate for sample alignment with the beam. A key challenge in using the gun system to acquire dynamic data on the nanosecond time scale was synchronization (or bracketing) of the impact event with the incident X-ray pulses (80 ps width). A description of the basic gun system used in previous work is provided along with details of an improved launch initiation system designed to significantly reduce the total system time from launch initiation to impact. Experiments were performed to directly measure the gun system time and to determine the gun performance curve for projectile velocities ranging from 0.3 to 0.9 km/s. All results show an average system time of 21.6 {+-} 4.5 ms, making it possible to better synchronize the gun system and detectors to the X-ray beam.

  8. Ultrafast Core-Hole Induced Dynamics in Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafast Core-Hole InducedUltrafast

  9. When Physics met Politics:When Physics met Politics: Physics of Politics? Politics of Physics?Physics of Politics? Politics of Physics?

    E-Print Network [OSTI]

    Chen, Yang-Yuan

    When Physics met Politics:When Physics met Politics: Physics of Politics? Politics of Physics?Physics of Politics? Politics of Physics? :: ?? ?? SaiSai--Ping LiPing Li Institute of Physics, Academia Sinica · Atomic and Molecular Physics · Particle Physics · Astrophysics · Nuclear Physics · Biophysics

  10. Towards simultaneous measurements of electronic and structural properties in ultra-fast x-ray free electron laser absorption spectroscopy experiments

    SciTech Connect (OSTI)

    Gaudin, J.; Fourment, C.; Cho, B. I.; Engelhorn, K.; Galtier, E.; Harmand, M.; Leguay, P. M.; Lee, H. J.; Nagler, B.; Nakatsutsumi, M.; Ozkan, C.; Störmer, M.; Toleikis, S.; Tschentscher, Th.; Heimann, P. A.; Dorchies, F.

    2014-04-17

    The rapidly growing ultrafast science with X-ray lasers unveils atomic scale processes with unprecedented time resolution bringing the so called “molecular movie” within reach. X-ray absorption spectroscopy is one of the most powerful x-ray techniques providing both local atomic order and electronic structure when coupled with ad-hoc theory. Collecting absorption spectra within few x-ray pulses is possible only in a dispersive setup. We demonstrate ultrafast time-resolved measurements of the LIII-edge x-ray absorption near-edge spectra of irreversibly laser excited Molybdenum using an average of only few x-ray pulses with a signal to noise ratio limited only by the saturation level of the detector. The simplicity of the experimental set-up makes this technique versatile and applicable for a wide range of pump-probe experiments, particularly in the case of non-reversible processes.

  11. Characterization and quantification of the role of coherence in ultrafast quantum biological experiments using quantum master equations, atomistic simulations, and quantum process tomography

    E-Print Network [OSTI]

    Rebentrost, Patrick; Yuen-Zhou, Joel; Aspuru-Guzik, Alán

    2010-01-01

    Long-lived electronic coherences in various photosynthetic complexes at cryogenic and room temperature have generated vigorous efforts both in theory and experiment to understand their origins and explore their potential role to biological function. The ultrafast signals resulting from the experiments that show evidence for these coherences result from many contributions to the molecular polarization. Quantum process tomography (QPT) was conceived in the context of quantum information processing to characterize and understand general quantum evolution of controllable quantum systems, for example while carrying out quantum computational tasks. We introduce our QPT method for ultrafast experiments, and as an illustrative example, apply it to a simulation of a two-chromophore subsystem of the Fenna-Matthews-Olson photosynthetic complex, which was recently shown to have long-lived quantum coherences. Our Fenna-Matthews-Olson model is constructed using an atomistic approach to extract relevant parameters for the s...

  12. Towards simultaneous measurements of electronic and structural properties in ultra-fast x-ray free electron laser absorption spectroscopy experiments

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gaudin, J.; Fourment, C.; Cho, B. I.; Engelhorn, K.; Galtier, E.; Harmand, M.; Leguay, P. M.; Lee, H. J.; Nagler, B.; Nakatsutsumi, M.; et al

    2014-04-17

    The rapidly growing ultrafast science with X-ray lasers unveils atomic scale processes with unprecedented time resolution bringing the so called “molecular movie” within reach. X-ray absorption spectroscopy is one of the most powerful x-ray techniques providing both local atomic order and electronic structure when coupled with ad-hoc theory. Collecting absorption spectra within few x-ray pulses is possible only in a dispersive setup. We demonstrate ultrafast time-resolved measurements of the LIII-edge x-ray absorption near-edge spectra of irreversibly laser excited Molybdenum using an average of only few x-ray pulses with a signal to noise ratio limited only by the saturation level ofmore »the detector. The simplicity of the experimental set-up makes this technique versatile and applicable for a wide range of pump-probe experiments, particularly in the case of non-reversible processes.« less

  13. PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORYA.M. Weiner Andrew M. Weiner, Jason McKinney*, and Shijun Xiao

    E-Print Network [OSTI]

    Purdue University

    PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORYA.M. Weiner Andrew M affiliation: Naval Research Labs #12;PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS bandwidth #12;PURDUE UNIVERSITY ULTRAFAST OPTICS & OPTICAL FIBER COMMUNICATIONS LABORATORYA.M. Weiner

  14. THE JOURNAL OF CHEMICAL PHYSICS 138, 034503 (2013) Generalized extended Navier-Stokes theory: Correlations in molecular

    E-Print Network [OSTI]

    2013-01-01

    of Engineering and Industrial Sciences, and Center for Molecular Simulation, Swinburne University of Technology be extended to study other frequency and wavevector dependent transport phenom- ena such as heat conductivity across a channel,14,16 and that it can be utilized to perform plane wave pumping.17 The coupling

  15. Apparatus and method for characterizing ultrafast polarization varying optical pulses

    DOE Patents [OSTI]

    Smirl, A.; Trebino, R.P.

    1999-08-10

    Practical techniques are described for characterizing ultrafast potentially ultraweak, ultrashort optical pulses. The techniques are particularly suited to the measurement of signals from nonlinear optical materials characterization experiments, whose signals are generally too weak for full characterization using conventional techniques. 2 figs.

  16. Development of ultrafast computed tomography of highly transient fuel sprays

    E-Print Network [OSTI]

    Gruner, Sol M.

    Development of ultrafast computed tomography of highly transient fuel sprays Xin Liu, Jinyuan Liu University, Ithaca, NY, USA 14853 ABSTRACT The detailed analysis of the fuel sprays has been well recognized emissions. However, the structure and dynamics of highly transient fuel sprays have never been visualized

  17. Ultrafast Diagnostics for Electron Beams from Laser Plasma Accelerators

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    Ultrafast Diagnostics for Electron Beams from Laser Plasma Accelerators N. H. Matlis, M. Bakeman, C key parameters of electron bunches from Laser Plasma Accelerators (LPAs). The diagnostics presented the ability to fine-tune and stabilize the electron beam parameters, however, is the ability to measure them

  18. 5D Data Storage by Ultrafast Laser Nanostructuring in Glass

    E-Print Network [OSTI]

    Anderson, Jim

    5D Data Storage by Ultrafast Laser Nanostructuring in Glass Jingyu Zhang* , Mindaugas Gecevicius-assembled form birefringence and retrieved in glass opening the era of unlimited lifetime data storage. © 2013 laser writing in glass were proposed for the polarization multiplexed optical memory, where

  19. ULTRAFAST RADIATION HEAT TRANSFER IN LASER TISSUE WELDING AND SOLDERING

    E-Print Network [OSTI]

    Guo, Zhixiong "James"

    , respectively. 1. INTRODUCTION The study of short-pulsed laser radiation transport and ultrafast matter­ radiation interactions is of great scientific and technological significance and is attracting increasing­9], to name a few. Due to the very short time duration of the radia- tion­matter interaction and transport

  20. Direct observation of ultrafast many-body electron dynamics in a strongly-correlated ultracold Rydberg gas

    E-Print Network [OSTI]

    Nobuyuki Takei; Christian Sommer; Claudiu Genes; Guido Pupillo; Haruka Goto; Kuniaki Koyasu; Hisashi Chiba; Matthias Weidemüller; Kenji Ohmori

    2015-04-14

    Many-body interactions govern a variety of important quantum phenomena ranging from superconductivity and magnetism in condensed matter to solvent effects in chemistry. Understanding those interactions beyond mean field is a holy grail of modern sciences. AMO physics with advanced laser technologies has recently emerged as a new platform to study quantum many-body systems. One of its latest developments is the study of long-range interactions among ultracold particles to reveal the effects of many-body correlations. Rydberg atoms distinguish themselves by their large dipole moments and tunability of dipolar interactions. Most of ultracold Rydberg experiments have been performed with narrow-band lasers in the Rydberg blockade regime. Here we demonstrate an ultracold Rydberg gas in a complementary regime, where electronic coherence is created using a broadband picosecond laser pulse, thus circumventing the Rydberg blockade to induce strong many-body correlations. The effects of long-range Rydberg interactions have been investigated by time-domain Ramsey interferometry with attosecond precision. This approach allows for the real-time observation of coherent and ultrafast many-body dynamics in which the electronic coherence is modulated by the interaction-induced correlations. The modulation evolves more rapidly than expected for two-body correlations by several orders of magnitude. We have actively controlled such ultrafast many-body dynamics by tuning the principal quantum number and the population of the Rydberg state. The observed Ramsey interferograms are well reproduced by a theoretical model beyond mean-field approximation, which can be relevant to other similar many-body phenomena in condensed matter physics and chemistry. Our new approach opens a new avenue to observe and manipulate nonequilibrium dynamics of strongly-correlated quantum many-body systems on the ultrafast timescale.

  1. Physical properties and band structure of reactive molecular beam epitaxy grown oxygen engineered HfO{sub 2{+-}x}

    SciTech Connect (OSTI)

    Hildebrandt, Erwin; Kurian, Jose; Alff, Lambert [Institute of Materials Science, Technische Universitaet Darmstadt, 64287 Darmstadt (Germany)

    2012-12-01

    We have conducted a detailed thin film growth structure of oxygen engineered monoclinic HfO{sub 2{+-}x} grown by reactive molecular beam epitaxy. The oxidation conditions induce a switching between (111) and (002) texture of hafnium oxide. The band gap of oxygen deficient hafnia decreases with increasing amount of oxygen vacancies by more than 1 eV. For high oxygen vacancy concentrations, defect bands form inside the band gap that induce optical transitions and p-type conductivity. The resistivity changes by several orders of magnitude as a function of oxidation conditions. Oxygen vacancies do not give rise to ferromagnetic behavior.

  2. PHYSICAL REVIEW B 83, 144113 (2011) Structural and thermodynamic properties of compressed palladium: Ab initio and molecular

    E-Print Network [OSTI]

    Alfè, Dario

    2011-01-01

    PHYSICAL REVIEW B 83, 144113 (2011) Structural and thermodynamic properties of compressed palladiumRevB.83.144113 PACS number(s): 05.70.-a, 65.40.-b, 62.20.-x, 74.10.+v I. INTRODUCTION Palladium has a wide systems and nanoscale devices fully highlighted the key role that palladium plays.3 For bulk systems

  3. PHYSICAL REVIEW B 85, 205440 (2012) Inelastic neutron scattering investigations of the quantum molecular dynamics of a H2 molecule

    E-Print Network [OSTI]

    Turro, Nicholas J.

    2012-01-01

    PHYSICAL REVIEW B 85, 205440 (2012) Inelastic neutron scattering investigations of the quantum transfer arising from the neutron scattering event has also been investigated. The -dependence spectra investigations using infrared (IR),3,13­15 inelastic neutron scattering (INS),3,16,17 and nuclear magnetic

  4. Ultra-fast Laser Synthesis of Nanopore Arrays in Silicon for Bio-molecule Separation and Detection

    SciTech Connect (OSTI)

    Tringe, J W; Ileri, N; Letant, S E; Stroeve, P; Shirk, M; Zaidi, S; Balhorn, R L; Siders, C W

    2008-02-07

    We demonstrate that interference of ultra-fast pulses of laser light can create regular patterns in thin silicon membranes that are compatible with the formation of a uniform array of nanopores. The spacing and size of these pores can be tuned by changing the laser energy, wavelength and number of ultra-short pulses. Short pulses and wavelengths ({approx}550 nm and smaller) are needed to define controllable nanoscale features in silicon. Energy must be localized in time and space to produce the etching, ablation or amorphization effects over the {approx}100 nm length scales appropriate for definition of single pores. Although in this brief study pattern uniformity was limited by laser beam quality, a complementary demonstration reported here used continuous-wave interferometric laser exposure of photoresist to show the promise of the ultra-fast approach for producing uniform pore arrays. The diameters of these interferometrically-defined features are significantly more uniform than the diameters of pores in state-of-the-art polycarbonate track etch membranes widely used for molecular separations.

  5. Ultrafast laser-induced changes in optical properties of semiconductors

    SciTech Connect (OSTI)

    Chirila, C. C.; Lim, Freda C. H.; Gavaza, M. G. [Institute of High Performance Computing, 1 Fusionopolis Way, 16-16 Connexis, 138632 (Singapore)

    2012-04-01

    We study the effect of laser radiation on optical properties of semiconductors of industrial interest. The material is pumped with a laser of chosen central frequency, for which the absorption is maximal, thus inducing electron dynamics, which modifies the optical properties. By using an improved theoretical model, we study ultrafast dynamic changes in the refraction index and reflectivity corresponding to a wide frequency-interval of probing radiation and identify that interval where these optical changes are most significant.

  6. ULTRACAM - an ultra-fast, triple-beam CCD camera

    E-Print Network [OSTI]

    Vik Dhillon; Tom Marsh; the ULTRACAM team

    2001-10-01

    ULTRACAM is an ultra-fast, triple-beam CCD camera which has been designed to study one of the few remaining unexplored regions of observational parameter space - high temporal resolution. The camera will see first light in Spring 2002, at a total cost of GBP 300 k, and will be used on 2-m, 4-m and 8-m class telescopes to study astrophysics on the fastest timescales.

  7. Ultrafast all-optical manipulation of interfacial magnetoelectric coupling

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal designUltrafast Transformations in

  8. Ultrafast laser ablation ICP-MS: role of spot size, laser fluence, and repetition rate in signal intensity

    E-Print Network [OSTI]

    Harilal, S. S.

    Ultrafast laser ablation ICP-MS: role of spot size, laser fluence, and repetition rate in signal,a Richard E. Russob and Ahmed Hassaneina Ultrafast laser ablation inductively coupled plasma mass system. Though ultrafast laser ablation sample introduction provides better accuracy and precision

  9. Non-Fourier heat transport in metal-dielectric core-shell nanoparticles under ultrafast laser pulse excitation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Non-Fourier heat transport in metal-dielectric core-shell nanoparticles under ultrafast laser and Baluchistan, Zahedan, Iran 10 PACS : Keywords : ballistic heat transfer, core-shell, nanoparticle, ultrafast laser Abstract15 Relaxation dynamics of embedded metal nanoparticles after ultrafast laser pulse

  10. RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS

    E-Print Network [OSTI]

    Guo, Zhixiong "James"

    RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS Kyunghan Kim to incorporate transient radiation heat transfer in tissue welding and soldering with use of ultrafast lasers are performed between laser welding and laser soldering. The use of solder is found to substantially enhance

  11. A pulsed electron gun for ultrafast electron diffraction at surfaces A. Janzen,a

    E-Print Network [OSTI]

    von der Linde, D.

    A pulsed electron gun for ultrafast electron diffraction at surfaces A. Janzen,a B. Krenzer, O The construction of a pulsed electron gun for ultrafast reflection high-energy electron diffraction experiments describe the construction of an elec- tron gun used in RHEED experiments at crystal surfaces

  12. Physics high-ranking Journals (category 2) Advances in Physics

    E-Print Network [OSTI]

    Bataillon, Thomas

    Physics high-ranking Journals (category 2) Advances in Physics Annual Review of Astronomy and Astrophysics Annual Review of Nuclear and Particle Science Applied Physics Letters Astronomy & Astrophysics Astronomy and Astrophysics Review Astrophysical Journal European Physical Journal D. Atomic, Molecular

  13. Ultrafast carrier capture in InGaAs quantum posts

    SciTech Connect (OSTI)

    Talbayev, Diyar; Taylor, Antoinette J; Stehr, D; Morris, C M; Wagner, M; Kim, H C; Schneider, H; Petroff, P M; Sherwin, M S

    2009-01-01

    To explore the capture dynamics of photoexcited carriers in semiconductor quantum posts, optical pump - THz probe and time-resolved photoluminescence spectroscopy were performed. The results of the THz experiment show that after ultrafast excitation, electrons relax within a few picoseconds into the quantum posts, which are acting as efficient traps. The saturation of the quantum post states, probed by photoluminescence, was reached approximately at ten times the quantum post density in the samples. The results imply that quantum posts are posts highly attractive nanostructures for future device applications.

  14. Ultrafast laser control of backward superfluorescence towards standoff sensing

    SciTech Connect (OSTI)

    Ariunbold, Gombojav O. [Texas A and M University, College Station, Texas 77843 (United States); National University of Mongolia, Ulaanbaatar 210646 (Mongolia); Baylor University, Waco, Texas 76798 (United States); Sautenkov, Vladimir A. [Texas A and M University, College Station, Texas 77843 (United States); Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412 (Russian Federation); P. N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow 119991 (Russian Federation); Rostovtsev, Yuri V. [University of North Texas, Denton, Texas 76203 (United States); Scully, Marlan O. [Texas A and M University, College Station, Texas 77843 (United States); Baylor University, Waco, Texas 76798 (United States); Princeton University, Princeton, New Jersey 08544 (United States)

    2014-01-13

    We study infrared backward cooperative emission in a rubidium vapor induced by ultrafast two-photon optical excitations. The laser coherent control of the backward emission is demonstrated by using a pair of 100 fs pulses with a variable time delay. The temporal variation (quantum beat) of the backward beam intensity due to interference of atomic transitions in the rubidium atomic level system 5S-5P-5D is produced and controlled. Based on the obtained experimental results, we discuss possible applications of the developed approach for creation of an effective “guide star” in the sodium atomic layer in the upper atmosphere (mesosphere)

  15. Rise Time Measurement for Ultrafast X-Ray Pulses

    DOE Patents [OSTI]

    Celliers, Peter M.; Weber, Franz A.; Moon, Stephen J.

    2005-04-05

    A pump-probe scheme measures the rise time of ultrafast x-ray pulses. Conventional high speed x-ray diagnostics (x-ray streak cameras, PIN diodes, diamond PCD devices) do not provide sufficient time resolution to resolve rise times of x-ray pulses on the order of 50 fs or less as they are being produced by modern fast x-ray sources. Here, we are describing a pump-probe technique that can be employed to measure events where detector resolution is insufficient to resolve the event. The scheme utilizes a diamond plate as an x-ray transducer and a p-polarized probe beam.

  16. Ultrafast Shock Initiation of Exothermic Chemistry in Hydrogen Peroxide

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and(Conference) |Article) |Fe(phen) 2 (NCS) 2Ultrafast Probes

  17. Ultrafast Shock Initiation of Exothermic Chemistry in Hydrogen Peroxide

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and(Conference) |Article) |Fe(phen) 2 (NCS) 2Ultrafast

  18. Ultrafast Core-Hole Induced Dynamics in Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuels forUltra-DeepwaterEnergyUltrafast

  19. Ultrafast Core-Hole Induced Dynamics in Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafast Core-Hole Induced Dynamics

  20. Ultrafast Core-Hole Induced Dynamics in Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafast Core-Hole Induced

  1. Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms:

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafast Core-Hole

  2. Ultrafast kinetics subsequent to shock in an unreacted, oxygen balanced

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal designUltrafast Transformations inmixture of

  3. Quantum Hooke's Law to classify pulse laser induced ultrafast melting

    SciTech Connect (OSTI)

    Hu, Hao; Ding, Hepeng; Liu, Feng

    2015-02-03

    Ultrafast crystal-to-liquid phase transition induced by femtosecond pulse laser excitation is an interesting material's behavior manifesting the complexity of light-matter interaction. There exist two types of such phase transitions: one occurs at a time scale shorter than a picosecond via a nonthermal process mediated by electron-hole plasma formation; the other at a longer time scale via a thermal melting process mediated by electron-phonon interaction. However, it remains unclear what material would undergo which process and why? Here, by exploiting the property of quantum electronic stress (QES) governed by quantum Hooke's law, we classify the transitions by two distinct classes of materials: the faster nonthermal process can only occur in materials like ice having an anomalous phase diagram characterized with dTm/dP < 0, where Tm is the melting temperature and P is pressure, above a high threshold laser fluence; while the slower thermal process may occur in all materials. Especially, the nonthermal transition is shown to be induced by the QES, acting like a negative internal pressure, which drives the crystal into a “super pressing” state to spontaneously transform into a higher-density liquid phase. Our findings significantly advance fundamental understanding of ultrafast crystal-to-liquid phase transitions, enabling quantitative a priori predictions.

  4. Quantum Hooke's Law to classify pulse laser induced ultrafast melting

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hu, Hao; Ding, Hepeng; Liu, Feng

    2015-02-03

    Ultrafast crystal-to-liquid phase transition induced by femtosecond pulse laser excitation is an interesting material's behavior manifesting the complexity of light-matter interaction. There exist two types of such phase transitions: one occurs at a time scale shorter than a picosecond via a nonthermal process mediated by electron-hole plasma formation; the other at a longer time scale via a thermal melting process mediated by electron-phonon interaction. However, it remains unclear what material would undergo which process and why? Here, by exploiting the property of quantum electronic stress (QES) governed by quantum Hooke's law, we classify the transitions by two distinct classes ofmore »materials: the faster nonthermal process can only occur in materials like ice having an anomalous phase diagram characterized with dTm/dP m is the melting temperature and P is pressure, above a high threshold laser fluence; while the slower thermal process may occur in all materials. Especially, the nonthermal transition is shown to be induced by the QES, acting like a negative internal pressure, which drives the crystal into a “super pressing” state to spontaneously transform into a higher-density liquid phase. Our findings significantly advance fundamental understanding of ultrafast crystal-to-liquid phase transitions, enabling quantitative a priori predictions.« less

  5. Atomic Resolution Coherent Diffractive Imaging and Ultrafast Science

    SciTech Connect (OSTI)

    Zuo, Jian-min (University of Illinois) [University of Illinois

    2011-01-12

    A major scientific challenge is determining the 3-D atomic structure of small nanostructures, including single molecules. Coherent diffractive imaging (CDI) is a promising approach. Recent progress has demonstrated coherent diffraction patterns can be recorded from individual nanostructures and phased to reconstruct their structure. However, overcoming the dose limit imposed by radiation damage is a major obstacle toward the full potential of CDI. One approach is to use ultrafast x-ray or electron pulses. In electron diffraction, amplitudes recorded in a diffraction pattern are unperturbed by lens aberrations, defocus, and other microscope resolution-limiting factors. Sub-A signals are available beyond the information limit of direct imaging. Significant contrast improvement is obtained compared to high-resolution electron micrographs. progress has also been made in developing time-resolved electron diffraction and imaging for the study of ultrafast dynamic processes in materials. This talk will cover these crosscutting issues and the convergence of electron and x-ray diffraction techniques toward structure determination of single molecules.

  6. Dynamic Processes in Biology, Chemistry, and Materials Science: Opportunities for UltraFast Transmission Electron Microscopy - Workshop Summary Report

    SciTech Connect (OSTI)

    Kabius, Bernd C.; Browning, Nigel D.; Thevuthasan, Suntharampillai; Diehl, Barbara L.; Stach, Eric A.

    2012-07-25

    This report summarizes a 2011 workshop that addressed the potential role of rapid, time-resolved electron microscopy measurements in accelerating the solution of important scientific and technical problems. A series of U.S. Department of Energy (DOE) and National Academy of Science workshops have highlighted the critical role advanced research tools play in addressing scientific challenges relevant to biology, sustainable energy, and technologies that will fuel economic development without degrading our environment. Among the specific capability needs for advancing science and technology are tools that extract more detailed information in realistic environments (in situ or operando) at extreme conditions (pressure and temperature) and as a function of time (dynamic and time-dependent). One of the DOE workshops, Future Science Needs and Opportunities for Electron Scattering: Next Generation Instrumentation and Beyond, specifically addressed the importance of electron-based characterization methods for a wide range of energy-relevant Grand Scientific Challenges. Boosted by the electron optical advancement in the last decade, a diversity of in situ capabilities already is available in many laboratories. The obvious remaining major capability gap in electron microscopy is in the ability to make these direct in situ observations over a broad spectrum of fast (µs) to ultrafast (picosecond [ps] and faster) temporal regimes. In an effort to address current capability gaps, EMSL, the Environmental Molecular Sciences Laboratory, organized an Ultrafast Electron Microscopy Workshop, held June 14-15, 2011, with the primary goal to identify the scientific needs that could be met by creating a facility capable of a strongly improved time resolution with integrated in situ capabilities. The workshop brought together more than 40 leading scientists involved in applying and/or advancing electron microscopy to address important scientific problems of relevance to DOE’s research mission. This workshop built on previous workshops and included three breakout sessions identifying scientific challenges in biology, biogeochemistry, catalysis, and materials science frontier areas of fundamental science that underpin energy and environmental science that would significantly benefit from ultrafast transmission electron microscopy (UTEM). In addition, the current status of time-resolved electron microscopy was examined, and the technologies that will enable future advances in spatio-temporal resolution were identified in a fourth breakout session.

  7. Studies of third-order nonlinearities in materials and devices for ultrafast lasers

    E-Print Network [OSTI]

    Gopinath, Juliet Tara, 1976-

    2005-01-01

    Recent developments in telecommunications, frequency metrology, and medical imaging have motivated research in ultrafast optics. Demand exists for broadband components and sources as well as highly nonlinear fibers and ...

  8. Ultrafast Laser Induced Thermo-Elasto-Visco-Plastodynamics in Single Crystalline Silicon 

    E-Print Network [OSTI]

    Qi, Xuele

    2011-02-22

    A comprehensive model for describing the fundamental mechanism dictating the interaction of ultrafast laser pulse with single crystalline silicon wafer is formulated. The need for establishing the feasibility of employing lasers of subpicosecond...

  9. Electromagnetically-driven ultra-fast tool servos for diamond turning

    E-Print Network [OSTI]

    Lu, Xiaodong, Ph. D. Massachusetts Institute of Technology

    2005-01-01

    This thesis presents the design, implementation, and control of a new class of fast tool servos (FTS). The primary thesis contributions include the design and experimental demonstration of: novel ultra-fast electromagnetic ...

  10. Direct Observation of Optically Induced Transient Structures in Graphite Using Ultrafast Electron Crystallography

    E-Print Network [OSTI]

    initio density functional calculations, we trace the governing mechanism back to electronic structure changes in the electronic properties, direct de- termination of lattice structural dynamics from opticalDirect Observation of Optically Induced Transient Structures in Graphite Using Ultrafast Electron

  11. Hydrogen Bond Dynamics Probed with Ultrafast Infrared Heterodyne-Detected Multidimensional Vibrational Stimulated Echoes

    E-Print Network [OSTI]

    Fayer, Michael D.

    Hydrogen Bond Dynamics Probed with Ultrafast Infrared Heterodyne-Detected Multidimensional, USA (Received 24 February 2003; published 3 December 2003) Hydrogen bond dynamics are explicated hydrogen bonded network are measured with ultrashort (

  12. Electron Pulse Compression with a Practical Reflectron Design for Ultrafast Electron Diffraction

    E-Print Network [OSTI]

    Wang, Yihua

    Ultrafast electron diffraction (UED) is a powerful method for studying time-resolved structural changes. Currently, space-charge-induced temporal broadening prevents obtaining high-brightness electron pulses with sub-100 ...

  13. Two photon luminescence from quantum dots using broad and narrowband ultrafast laser pulses 

    E-Print Network [OSTI]

    Balasubramanian, Haribhaskar

    2008-10-10

    Nonlinear optical microscopy (NLOM) offers many advantages when imaging intact biological samples. By using ultrafast lasers in the near infrared and two photon excitation (TPE), signal production is limited to the focal volume and provides...

  14. Ultrafast Dynamics of 1,3-Cyclohexadiene in Highly Excited States

    E-Print Network [OSTI]

    Minitti, Michael P.

    2011-01-01

    The ultrafast dynamics of 1,3-cyclohexadiene has been investigated via structurally sensitive Rydberg electron binding energies and shown to differ upon excitation to the 1B state and the 3p Rydberg state. Excitation of ...

  15. Ultrafast optical switching of three-dimensional Si inverse opal photonic band gap crystals

    E-Print Network [OSTI]

    Vos, Willem L.

    Ultrafast optical switching of three-dimensional Si inverse opal photonic band gap crystals Tijmen on three-dimensional photonic band gap crystals. Switching the Si inverse opal is achieved by optically

  16. Ultrafast Photo-Induced Charge Transfer Unveiled by Two-Dimensional Electronic Spectroscopy

    E-Print Network [OSTI]

    Bixner, Oliver; Mancal, Tomas; Hauer, Juergen; Milota, Franz; Fischer, Michael; Pugliesi, Igor; Bradler, Maximilian; Schmid, Walther; Riedle, Eberhard; Kauffmann, Harald F; Christensson, Niklas

    2012-01-01

    The interaction of exciton and charge transfer (CT) states plays a central role in photo-induced CT processes in chemistry, biology and physics. In this work, we use a combination of two-dimensional electronic spectroscopy (2D-ES), pump-probe measurements and quantum chemistry to investigate the ultrafast CT dynamics in a lutetium bisphthalocyanine dimer in different oxidation states. It is found that in the anionic form, the combination of strong CT-exciton interaction and electronic asymmetry induced by a counter-ion enables CT between the two macrocycles of the complex on a 30 fs timescale. Following optical excitation, a chain of electron and hole transfer steps gives rise to characteristic cross-peak dynamics in the electronic 2D spectra, and we monitor how the excited state charge density ultimately localizes on the macrocycle closest to the counter-ion within 100 fs. A comparison with the dynamics in the radical species further elucidates how CT states modulate the electronic structure and tune fs-reac...

  17. Phase-contrast imaging using ultrafast x-rays in laser-shocked materials

    SciTech Connect (OSTI)

    Workman, Jonathan B; Cobble, James A; Flippo, Kirk; Gautier, Donald C; Montgomery, David S; Offermann, Dustin T

    2010-01-01

    High-energy x-rays, > 10-keV, can be efficiently produced from ultrafast laser target interactions with many applications to dense target materials in Inertial Confinement Fusion (ICF) and High-Energy Density Physics (HEDP). These same x-rays can also be applied to measurements of low-density materials inside high-density hohlraum environments. In the experiments presented, high-energy x-ray images of laser-shocked polystyrene are produced through phase contrast imaging. The plastic targets are nominally transparent to traditional x-ray absorption but show detailed features in regions of high density gradients due to refractive effects often called phase contrast imaging. The 200-TW Trident laser is used both to produce the x-ray source and to shock the polystyrene target. X-rays at 17-keV produced from 2-ps, 100-J laser interactions with a 12-micron molybdenum wire are used to produce a small source size, required for optimizing refractive effects. Shocks are driven in the 1-mm thick polystyrene target using 2-ns, 250-J, 532-nm laser drive with phase plates. X-ray images of shocks compare well to 1-D hydro calculations, HELIOS-CR.

  18. Ultrafast dynamic ellipsometry and spectroscopy of laser shocked materials

    SciTech Connect (OSTI)

    Mcgrane, Shawn David [Los Alamos National Laboratory; Bolme, Cindy B [Los Alamos National Laboratory; Whitley, Von H [Los Alamos National Laboratory; Moore, David S [Los Alamos National Laboratory

    2010-01-01

    Shock waves create extreme states of matter with very high pressures, temperatures, and volumetric compressions, at an exceedingly rapid rate of change. We review how to use a beamsplitter and a note card to turn a typical chirp pulse amplified femtosecond laser system into an ultrafast shock dynamics machine. Open scientific questions that can be addressed with such an apparatus are described. We report on the development of several single shot time resolved diagnostics needed to answer these questions. These single shot diagnostics are expected to be broadly applicable to other types of laser ablation experiments. Experimental results measured from shocked material dynamics of several systems are detailed. Finally, we report on progress towards using transient absorption as a measure of electronic excitation and coherent Raman as a picosecond probe of temperature in shock compressed condensed matter.

  19. Ultrafast Optimal Sideband Cooling under Non-Markovian Evolution

    E-Print Network [OSTI]

    Johan F. Triana; Andrés F. Estrada; Leonardo A. Pachon

    2015-08-20

    A sideband cooling strategy that incorporates (i) the dynamics induced by structured (non-Markovian) environments in the target and auxiliary systems and (ii) the optimally-time-modulated interaction between them is developed. For the context of cavity optomechanics, when non-Markovian dynamics are considered in the target system, ground state cooling is reached at much faster rates and at much lower phonon occupation number than previously reported. In constrast to similar current strategies, ground state cooling is reached here for coupling-strength rates that are experimentally accesible for the state-of-the-art implementations. After the ultrafast optimal-ground-state-cooling protocol is accomplished, an additional optimal control strategy is considered to maintain the phonon number as closer as possible to the one obtained in the cooling procedure. Contrary to the conventional expectation, when non-Markovian dynamics are considered in the auxiliary system, the efficiency of the cooling protocol is undermined.

  20. Ultrafast stimulated Raman parallel adiabatic passage by shaped pulses

    SciTech Connect (OSTI)

    Dridi, G.; Guerin, S.; Hakobyan, V.; Jauslin, H. R.; Eleuch, H.

    2009-10-15

    We present a general and versatile technique of population transfer based on parallel adiabatic passage by femtosecond shaped pulses. Their amplitude and phase are specifically designed to optimize the adiabatic passage corresponding to parallel eigenvalues at all times. We show that this technique allows the robust adiabatic population transfer in a Raman system with the total pulse area as low as 3{pi}, corresponding to a fluence of one order of magnitude below the conventional stimulated Raman adiabatic passage process. This process of short duration, typically picosecond and subpicosecond, is easily implementable with the modern pulse shaper technology and opens the possibility of ultrafast robust population transfer with interesting applications in quantum information processing.

  1. IOP PUBLISHING JOURNAL OF PHYSICS B: ATOMIC, MOLECULAR AND OPTICAL PHYSICS J. Phys. B: At. Mol. Opt. Phys. 40 (2007) S299S313 doi:10.1088/0953-4075/40/11/S05

    E-Print Network [OSTI]

    Vardi, Amichay

    2007-01-01

    of a molecular Bose­Einstein condensate I Tikhonenkov and A Vardi Department of Chemistry, Ben-Gurion University the collective two-channel dissociation dynamics of a molecular Bose­Einstein condensate into bosonic fragments under tight harmonic confinement. Bose-stimulated dissociation in either channel can only take place

  2. Ultrafast Shock Initiation of Exothermic Chemistry in Hydrogen...

    Office of Scientific and Technical Information (OSTI)

    Language: English Subject: 71 CLASSICAL AND QUANTUMM MECHANICS, GENERAL PHYSICS; 36 MATERIALS SCIENCE; 42 ENGINEERING; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY...

  3. Offered Fall Semester: Biological Physics

    E-Print Network [OSTI]

    Collins, Gary S.

    Offered Fall Semester: Biological Physics Physics 466 / Physics 566 (conjoint) provides a fundamental physical understanding of the operation of cells, biomolecules and molecular machines. MWF 4:10-5:00pm, Webster 11 (3 cr) Instructor: Fred Gittes, Clinical Professor of Physics and Astronomy: gittes

  4. Semiclassical molecular dynamics simulations of ultrafast photodissociation dynamics associated with the Chappuis band of ozone

    E-Print Network [OSTI]

    Miller, William H.

    with the Chappuis band of ozone Victor S. Batista and William H. Millera) Department of Chemistry, University A ) of ozone following photoexcitation of the molecule in the gas phase with visible light. Our algorithm and recurrence events, as well as an interpretation of experimental studies of the Chappuis band of ozone

  5. Quantitative comparison of fuel spray images obtained using ultrafast coherent and incoherent double-pulsed illumination

    E-Print Network [OSTI]

    Purwar, Harsh; Idlahcen, Saïd; Rozé, Claude; Blaisot, Jean-Bernard; Ménard, Thibault

    2015-01-01

    We present a quantitative comparison between the high-pressure fuel spray images obtained experimentally using classical imaging with coherent and incoherent ultrafast illuminations recorded using a compatible CMOS camera. The ultrafast, incoherent illumination source was extracted from the supercontinuum generated by tightly focusing the femtosecond laser pulses in water. The average velocity maps computed using time-correlated image-pairs and spray edge complexity computed using the average curvature scale space maps are compared for the spray images obtained with the two illumination techniques and also for the numerically simulated spray using the coupled volume of fluid and level set method for interface tracking (direct numerical simulation or DNS). The spray images obtained with supercontinuum-derived, incoherent, ultrafast illumination are clearer, since the artifacts arising due to laser speckles and multiple diffraction effects are largely reduced and show a better correlation with the DNS results.

  6. Extension - Upgrading Methane Using Ultra-Fast Thermal Swing Adsorption

    SciTech Connect (OSTI)

    Anna Lee Tonkovich

    2008-08-11

    The need for cost effective technologies for upgrading coal mine methane to pipeline quality natural gas is becoming ever greater. The current work presents and investigates a new approach to reduce the impact of the most costly step in the conventional technology, nitrogen rejection. The proposed approach is based on the Velocys microchannel platform, which is being developed to commercialize compact and cost efficient chemical processing technology. For this separation, ultra fast thermal swing sorption is enabled by the very high rates of heat and mass transfer inherent in microchannel processing. In a first phase of the project solid adsorbents were explored. Feasibility of ultrafast thermal swing was demonstrated but the available adsorbents had insufficient differential methane capacity to achieve the required commercial economics. In a second phase, ionic liquids were adopted as absorbents of choice, and experimental work and economic analyses, performed to gauge their potential, showed promise for this novel alternative. Final conclusions suggest that a combination of a required cost target for ionic liquids or a methane capacity increase or a combination of both is required for commercialization.

  7. ULTRAFAST OUTFLOWS: GALAXY-SCALE ACTIVE GALACTIC NUCLEUS FEEDBACK

    SciTech Connect (OSTI)

    Wagner, A. Y.; Umemura, M.; Bicknell, G. V.

    2013-01-20

    We show, using global three-dimensional grid-based hydrodynamical simulations, that ultrafast outflows (UFOs) from active galactic nuclei (AGNs) result in considerable feedback of energy and momentum into the interstellar medium (ISM) of the host galaxy. The AGN wind interacts strongly with the inhomogeneous, two-phase ISM consisting of dense clouds embedded in a tenuous, hot, hydrostatic medium. The outflow floods through the intercloud channels, sweeps up the hot ISM, and ablates and disperses the dense clouds. The momentum of the UFO is primarily transferred to the dense clouds via the ram pressure in the channel flow, and the wind-blown bubble evolves in the energy-driven regime. Any dependence on UFO opening angle disappears after the first interaction with obstructing clouds. On kpc scales, therefore, feedback by UFOs operates similarly to feedback by relativistic AGN jets. Negative feedback is significantly stronger if clouds are distributed spherically rather than in a disk. In the latter case, the turbulent backflow of the wind drives mass inflow toward the central black hole. Considering the common occurrence of UFOs in AGNs, they are likely to be important in the cosmological feedback cycles of galaxy formation.

  8. Isotopically Enriched Films and Nanostructures by Ultrafast Pulsed Laser Deposition

    SciTech Connect (OSTI)

    Peter Pronko

    2004-12-13

    This project involved a systematic study to apply newly discovered isotopic enrichment effects in laser ablation plumes to the fabrication of isotopically engineered thin films, superlattices, and nanostructures. The approach to this program involved using ultrafast lasers as a method for generating ablated plasmas that have preferentially structured isotopic content in the body of the ablation plasma plumes. In examining these results we have attempted to interpret the observations in terms of a plasma centrifuge process that is driven by the internal electro-magnetic fields of the plasma itself. The research plan involved studying the following phenomena in regard to the ablation plume and the isotopic mass distribution within it: (1) Test basic equations of steady state centrifugal motion in the ablation plasma. (2) Investigate angular distribution of ions in the ablation plasmas. (3) Examine interactions of plasma ions with self-generated magnetic fields. (3) Investigate ion to neutral ratios in the ablation plasmas. (5) Test concepts of plasma pumping. (6) Fabricate isotopically enriched nanostructures.

  9. Ultrafast Dynamic Response of Single Crystal PETN and Beta-HMX (Conference)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafast Core-Hole InducedUltrafast|

  10. Ultrafast Probes for Dirac Materials (Technical Report) | SciTech Connect

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafast Core-HoleUltrafast

  11. Ultrafast Terahertz-Induced Response of GeSbTe Phase-Change Materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinal design andBiofuelsUltrafastUltrafast

  12. Current Theoretical Challenges in Proton-Coupled Electron Transfer: Electron Proton Nonadiabaticity, Proton Relays, and Ultrafast Dynamics

    SciTech Connect (OSTI)

    Hammes-Schiffer, Sharon

    2011-06-16

    Proton-coupled electron transfer (PCET) reactions play an important role in a wide range of biological and chemical processes. The motions of the electrons, transferring protons, solute nuclei, and solvent nuclei occur on a wide range of time scales and are often strongly coupled. As a result, the theoretical description of these processes requires a combination of quantum and classical methods. This Perspective discusses three of the current theoretical challenges in the field of PCET. The first challenge is the calculation of electron proton nonadiabatic effects, which are significant for these reactions because the hydrogen tunneling is often faster than the electronic transition. The second challenge is the modeling of electron transfer coupled to proton transport along hydrogen-bonded networks. The third challenge is the simulation of the ultrafast dynamics of nonequilibrium photoinduced PCET reactions in solution. Insights provided by theoretical studies may assist in the design of more effective catalysts for energy conversion processes. The proton relay portion of this review is based upon work supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences.

  13. Volume 75, number 1 CHEMICAL PHYSICS LETTERS 1 October 1980 ISOMERIZATION DYNAMICS lN LiQUlDS BY MOLECULAR DYNAMlCS*

    E-Print Network [OSTI]

    Berne, Bruce J.

    are made of lsomerlzatlon dynamrcs of lz-butane dissolved m hquld CC14 and m a r&ud matrl\\ Rate constants,-CH, 2 _cH kz_ (gauche) " (trans) .CH, m wfuch n-butane undergoes a gauche-trans Isomen- zahon. The stage for this work is set by our previous molecular dynamics and Monte Carlo studies of n- butane in hquid Ccl, [l

  14. Ultrafast Spectroscopy of CdSe Nanocrystals: Morphological and Environmental Effects on Nonradiative and Nonadiabatic Relaxation

    E-Print Network [OSTI]

    Xu, Xianfan

    Ultrafast Spectroscopy of CdSe Nanocrystals: Morphological and Environmental Effects of various morpholo- gies has been demonstrated in CdSe, such as quantum dots (QDs),3 quantum rods (QRs),4 devices and technologies have come to fruition, for example, nanocrystal solar cells (NCSC),7 lasers,8

  15. HARMONIC CASCADE FEL DESIGNS FOR LUX, A FACILTY FOR ULTRAFAST X-RAY SCIENCE

    E-Print Network [OSTI]

    Wurtele, Jonathan

    HARMONIC CASCADE FEL DESIGNS FOR LUX, A FACILTY FOR ULTRAFAST X-RAY SCIENCE J. Corlett, W. Fawley. We also discuss lattice considerations pertinent to harmonic cascade FELs, somesensitivity studies. While much of this effort has been concentrated upon SASE-based FEL's, there is an alternative "harmonic

  16. Optical Deflection and Temporal Characterization of an Ultrafast Laser-Produced Electron Beam

    E-Print Network [OSTI]

    Umstadter, Donald

    Optical Deflection and Temporal Characterization of an Ultrafast Laser-Produced Electron Beam) The interaction of a laser-produced electron beam with an ultraintense laser pulse in free space is studied. We show that the optical pulse with a0 0:5 imparts momentum to the electron beam, causing it to deflect

  17. Ultrafast dynamics of nonequilibrium electrons in metals under femtosecond laser irradiation B. Rethfeld*

    E-Print Network [OSTI]

    von der Linde, D.

    Ultrafast dynamics of nonequilibrium electrons in metals under femtosecond laser irradiation B with an ultrashort laser pulse leads to a disturbance of the free-electron gas out of thermal equilibrium. We investigate theoretically the transient evolution of the distribution function of the electron gas in a metal

  18. 1 Copyright 2007 by ASME THE ROLE OF THERMAL EXCITATION OF D BAND ELECTRONS IN ULTRAFAST

    E-Print Network [OSTI]

    Zhigilei, Leonid V.

    1 Copyright © 2007 by ASME THE ROLE OF THERMAL EXCITATION OF D BAND ELECTRONS IN ULTRAFAST LASER://www.faculty.virginia.edu/CompMat/ ABSTRACT The temperature dependences of the electron heat capacity and electron-phonon coupling factor for noble (Cu) and transition (Pt) metals are investigated based on the electron density of states (DOS

  19. Control of ultrafast electron dynamics with shaped femtosecond laser pulses: from atoms to solids

    E-Print Network [OSTI]

    Peinke, Joachim

    focus on advanced control of ultrafast electron dynamics with shaped femtosecond laser pulses of a femtosecond laser pulse, in addition to its temporal envelope and phase. Before we present some recent the photoionization of potassium atoms with a phase-coherent double pulse sequence. Building on this simple example we

  20. Water at the Surfaces of Aligned Phospholipid Multibilayer Model Membranes Probed with Ultrafast Vibrational

    E-Print Network [OSTI]

    Fayer, Michael D.

    Water at the Surfaces of Aligned Phospholipid Multibilayer Model Membranes Probed with Ultrafast@stanford.edu Abstract: The dynamics of water at the surface of artificial membranes composed of aligned multibilayers pump-probe spectroscopy. The experiments are performed at various hydration levels, x ) 2 - 16 water

  1. Dynamics of Hemoglobin in Human Erythrocytes and in Solution: Influence of Viscosity Studied by Ultrafast

    E-Print Network [OSTI]

    Fayer, Michael D.

    Dynamics of Hemoglobin in Human Erythrocytes and in Solution: Influence of Viscosity Studied by Ultrafast Vibrational Echo Experiments Brian L. McClain, Ilya J. Finkelstein, and M. D. Fayer* Contribution experiments are used to measure the vibrational dephasing of the CO stretching mode of hemoglobin-CO (Hb

  2. Large and ultrafast third-order optical nonlinearity of heteroleptic triple-decker

    E-Print Network [OSTI]

    Huang, Yanyi

    Large and ultrafast third-order optical nonlinearity of heteroleptic triple-decker Abstract The third-order optical nonlinearity of two triple-decker mixed phthalocyaninato and porphyrinato investigated for several homoleptic double- decked diphthalocyanines [8,9]. One interesting property

  3. Ultrafast conversions between hydrogen bonded structures in liquid water observed by femtosecond x-ray spectroscopy

    E-Print Network [OSTI]

    Ultrafast conversions between hydrogen bonded structures in liquid water observed by femtosecond x the first femtosecond soft x-ray spectroscopy in liquids, enabling the observation of changes in hydrogen, characteristic x-ray absorption changes monitor the conversion of strongly hydrogen-bonded water structures

  4. Water Dynamics in Salt Solutions Studied with Ultrafast Two-Dimensional Infrared (2D IR)

    E-Print Network [OSTI]

    Fayer, Michael D.

    Water Dynamics in Salt Solutions Studied with Ultrafast Two-Dimensional Infrared (2D IR. Many of these species are charged. In the ocean, water interacts with dissolved salts. In biological systems, water interacts with dissolved salts as well as charged amino acids, the zwitterionic head groups

  5. Metastable phase formation in the Au-Si system via ultrafast nanocalorimetry

    E-Print Network [OSTI]

    Allen, Leslie H.

    Metastable phase formation in the Au-Si system via ultrafast nanocalorimetry M. Zhang, J. G. Wen, M://jap.aip.org/features/most_downloaded Information for Authors: http://jap.aip.org/authors #12;Metastable phase formation in the Au-Si system via of Materials Science and Engineering and Coordinated Science Laboratory, University of Illinois at Urbana

  6. DEVELOPMENT OF NEW MID-INFRARED ULTRAFAST LASER SOURCES FOR COMPACT COHERENT X-RAY SOURCES

    SciTech Connect (OSTI)

    Sterling Backus

    2012-05-14

    In this project, we proposed to develop laser based mid-infrared lasers as a potentially robust and reliable source of ultrafast pulses in the mid-infrared region of the spectrum, and to apply this light source to generating bright, coherent, femtosecond-to-attosecond x-ray beams.

  7. Analysis of the Ultra-fast Switching Dynamics in a Hybrid MOSFET/Driver

    SciTech Connect (OSTI)

    Tang, T.; Burkhart, C.; /SLAC

    2011-08-17

    The turn-on dynamics of a power MOSFET during ultra-fast, {approx} ns, switching are discussed in this paper. The testing was performed using a custom hybrid MOSFET/Driver module, which was fabricated by directly assembling die-form components, power MOSFET and drivers, on a printed circuit board. By using die-form components, the hybrid approach substantially reduces parasitic inductance, which facilitates ultra-fast switching. The measured turn on time of the hybrid module with a resistive load is 1.2 ns with an applied voltage of 1000 V and drain current of 33 A. Detailed analysis of the switching waveforms reveals that switching behavior must be interpreted differently in the ultra-fast regime. For example, the gate threshold voltage to turn on the device is observed to increase as the switching time decreases. Further analysis and simulation of MOSFET switching behavior shows that the minimum turn on time scales with the product of the drain-source on resistance and drain-source capacitance, R{sub DS(on)}C{sub OSS}. This information will be useful in power MOSFET selection and gate driver design for ultra-fast switching applications.

  8. Ultrafast Photovoltaic Response in Ferroelectric Nanolayers Dan Daranciang,1,2,3

    E-Print Network [OSTI]

    Ultrafast Photovoltaic Response in Ferroelectric Nanolayers Dan Daranciang,1,2,3 Matthew J direct coupling to its intrinsic photovoltaic response. Using time-resolved x- ray scattering nanometer-scale domains of alternating polarization that minimize the free energy of the system [3

  9. Ultra-Fast Absorption of Amorphous Pure Drug Aerosols Via Deep Lung Inhalation

    E-Print Network [OSTI]

    Rabinowitz, Joshua D.

    Ultra-Fast Absorption of Amorphous Pure Drug Aerosols Via Deep Lung Inhalation JOSHUA D. RABINOWITZ. A promising means of accelerating drug action is through rapid systemic drug administration via deep lung inhalation. The speed of pulmonary drug absorption depends on the site of aerosol deposition within the lung

  10. Neuroglobin dynamics observed with ultrafast 2D-IR vibrational echo spectroscopy

    E-Print Network [OSTI]

    Fayer, Michael D.

    Neuroglobin dynamics observed with ultrafast 2D-IR vibrational echo spectroscopy Haruto Ishikawa Contributed by Michael D. Fayer, August 15, 2007 (sent for review July 25, 2007) Neuroglobin (Ngb), a protein energy minimum. myoglobin mutants protein dynamics energy landscape Neuroglobin (Ngb) is a recently

  11. Ultrafast-based projection-reconstruction three-dimensional nuclear magnetic resonance spectroscopy

    E-Print Network [OSTI]

    Frydman, Lucio

    Ultrafast-based projection-reconstruction three-dimensional nuclear magnetic resonance spectroscopy Eriks Kupce Varian Ltd., 28 Manor Road, Walton-on-Thames, Surrey KT12 2QF, United Kingdom Lucio Frydmana the accelerated acquisition of multidimensional nuclear magnetic resonance nD NMR spectra. Among the methods

  12. Physics Division annual report - 1998

    SciTech Connect (OSTI)

    NONE

    1999-09-07

    Summaries are given of progress accomplished for the year in the following areas: (1) Heavy-Ion Nuclear Physics Research; (2) Operation and Development of Atlas; (3) Medium-Energy Nuclear Physics Research; (4) Theoretical Physics Research; and (5) Atomic and Molecular Physics Research.

  13. About the Applied Physics Career Applied physics is a general term for physics which is

    E-Print Network [OSTI]

    Walker, Lawrence R.

    ://www.unlv.edu/sciences/advising Applied Physics Career Options · Nuclear Physics* · Geophysics* · Atomic, molecular, optics physics, geoscience, mathematical sciences, physics and astronomy, and water management. The college has created a well-rounded curriculum by combining practical and empirical knowledge with scientific fundamentals

  14. REVEALING THE PHYSICAL PROPERTIES OF MOLECULAR GAS IN ORION WITH A LARGE-SCALE SURVEY IN J = 2-1 LINES OF {sup 12}CO, {sup 13}CO, AND C{sup 18}O

    SciTech Connect (OSTI)

    Nishimura, Atsushi; Tokuda, Kazuki; Kimura, Kimihiro; Muraoka, Kazuyuki; Maezawa, Hiroyuki; Ogawa, Hideo; Onishi, Toshikazu [Department of Physical Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531 (Japan); Dobashi, Kazuhito; Shimoikura, Tomomi [Department of Astronomy and Earth Sciences, Tokyo Gakugei University, 4-1-1 Nukuikita-machi, Koganei, Tokyo 184-8501 (Japan); Mizuno, Akira [Solar-terrestrial Environment Laboratory, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Fukui, Yasuo, E-mail: atsushi.nishimura@nao.ac.jp [Department of Physics and Astrophysics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602 (Japan)

    2015-01-01

    We present fully sampled ?3' resolution images of {sup 12}CO(J = 2-1), {sup 13}CO(J = 2-1), and C{sup 18}O(J = 2-1) emission taken with the newly developed 1.85 m millimeter-submillimeter telescope over the entire area of the Orion A and B giant molecular clouds. The data were compared with J = 1-0 of the {sup 12}CO, {sup 13}CO, and C{sup 18}O data taken with the Nagoya 4 m telescope and the NANTEN telescope at the same angular resolution to derive the spatial distributions of the physical properties of the molecular gas. We explore the large velocity gradient formalism to determine the gas density and temperature using line combinations of {sup 12}CO(J = 2-1), {sup 13}CO(J = 2-1), and {sup 13}CO(J = 1-0) assuming a uniform velocity gradient and abundance ratio of CO. The derived gas density is in the range of 500 to 5000 cm{sup –3}, and the derived gas temperature is mostly in the range of 20 to 50 K along the cloud ridge with a temperature gradient depending on the distance from the star forming region. We found that the high-temperature region at the cloud edge faces the H II region, indicating that the molecular gas is interacting with the stellar wind and radiation from the massive stars. In addition, we compared the derived gas properties with the young stellar objects distribution obtained with the Spitzer telescope to investigate the relationship between the gas properties and the star formation activity therein. We found that the gas density and star formation efficiency are positively well correlated, indicating that stars form effectively in the dense gas region.

  15. Navigating Space-Time with Ultrafast Exciton Photolithography...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    all underpinned by the strong correlation between physical structure and the optical properties of materials. Our investigations often require tailoring the spatial and...

  16. Ultrafast Core-Hole Induced Dynamics in Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    is essential for many diverse fields, from condensed matter physics to medicine to environmental science. An incoming photon with enough energy to produce a core hole in a...

  17. PHYSICAL REVIEW B 84, 094502 (2011) Nondeterministic ultrafast ground-state cooling of a mechanical resonator

    E-Print Network [OSTI]

    2011-01-01

    a Cooper pair box15 or single-shot state-swapping cooling via a superconductor.18 Recently, some of us13

  18. Modified ultrafast thermometer UFT-M and temperature measurements during Physics of Stratocumulus Top (POST)

    E-Print Network [OSTI]

    Kumala, W.; Haman, K. E; Kopec, M. K; Khelif, D.; Malinowski, S. P

    2013-01-01

    metadata after error correction, calibration, visual signal inspection and comparison of the two UFT- M temperature sensors

  19. Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms: Tools for Physics-Based Model Development

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnicalInformation4563 LLNL Small-scale Friction Sensitivity (BAM) Test

  20. Molecular Foundry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Flatter and Faster: Transition Metal Dichalcogendies at the Molecular Foundry (Part II) Brain Imaging and Optical Manipulation Active Nanointerfaces for Electrochemistry SAXS-WAXS...

  1. MAJOR TO CAREER GUIDE B.S. Physics

    E-Print Network [OSTI]

    Walker, Lawrence R.

    . Physics Career Options · Nuclear Physics* · Geophysics* · Atomic, molecular, optics physics* · Astronomy sciences, physics and astronomy, and water management. The college has created a well-rounded curriculum by combining practical and empirical knowledge with scientific fundamentals and principles, which provides

  2. Ultrafast Power Processor for Smart Grid Power Module Development

    SciTech Connect (OSTI)

    MAITRA, ARINDAM; LITWIN, RAY; lai, Jason; Syracuse, David

    2012-12-30

    This project’s goal was to increase the switching speed and decrease the losses of the power semiconductor devices and power switch modules necessary to enable Smart Grid energy flow and control equipment such as the Ultra-Fast Power Processor. The primary focus of this project involves exploiting the new silicon-based Super-GTO (SGTO) technology and build on prototype modules already being developed. The prototype super gate-turn-off thyristor (SGTO) has been tested fully under continuously conducting and double-pulse hard-switching conditions for conduction and switching characteristics evaluation. The conduction voltage drop measurement results indicate that SGTO has excellent conduction characteristics despite inconsistency among some prototype devices. Tests were conducted with two conditions: (1) fixed gate voltage and varying anode current condition, and (2) fixed anode current and varying gate voltage condition. The conduction voltage drop is relatively a constant under different gate voltage condition. In terms of voltage drop as a function of the load current, there is a fixed voltage drop about 0.5V under zero current condition, and then the voltage drop is linearly increased with the current. For a 5-kV voltage blocking device that may operate under 2.5-kV condition, the projected voltage drop is less than 2.5 V under 50-A condition, or 0.1%. If the device is adopted in a converter operating under soft-switching condition, then the converter can achieve an ultrahigh efficiency, typically above 99%. The two-pulse switching test results indicate that SGTO switching speed is very fast. The switching loss is relatively low as compared to that of the insulated-gate-bipolar-transistors (IGBTs). A special phenomenon needs to be noted is such a fast switching speed for the high-voltage switching tends to create an unexpected C?dv/dt current, which reduces the turn-on loss because the dv/dt is negative and increases the turn-off loss because the dv/dt is positive. As a result, the turn-on loss at low current is quite low, and the turn-off loss at low current is relatively high. The phenomenon was verified with junction capacitance measurement along with the dv/dt calculation. Under 2-kV test condition, the turn-on and turn-off losses at 25-A is about 3 and 9 mJ, respectively. As compared to a 4.5-kV, 60-A rated IGBT, which has turn-on and turn-off losses about 25 and 20 mJ under similar test condition, the SGTO shows significant switching loss reduction. The switching loss depends on the switching frequency, but under hard-switching condition, the SGTO is favored to the IGBT device. The only concern is during low current turn-on condition, there is a voltage bump that can translate to significant power loss and associated heat. The reason for such a current bump is not known from this study. It is necessary that the device manufacturer perform though test and provide the answer so the user can properly apply SGTO in pulse-width-modulated (PWM) converter and inverter applications.

  3. Molecular Biology The molecular biology major at Stetson University is designed for

    E-Print Network [OSTI]

    Miles, Will

    Molecular Biology The molecular biology major at Stetson University is designed for students interested in the interface between the life sciences and physical sciences. Molecular biology is an interdisciplinary science that uses the techniques of biology and chemistry to examine genetic inheritance

  4. Time-domain sampling of x-ray pulses using an ultrafast sample response

    SciTech Connect (OSTI)

    Gaal, P.; Shayduk, R.; Schick, D.; Herzog, M.; Bojahr, A.; Goldshteyn, J.; Navirian, H. A.; Leitenberger, W.; Vrejoiu, I.; Khakhulin, D.; Wulff, M.; Bargheer, M.

    2012-12-10

    We employ the ultrafast response of a 15.4 nm thin SrRuO{sub 3} layer grown epitaxially on a SrTiO{sub 3} substrate to perform time-domain sampling of an x-ray pulse emitted from a synchrotron storage ring. Excitation of the sample with an ultrashort laser pulse triggers coherent expansion and compression waves in the thin layer, which turn the diffraction efficiency on and off at a fixed Bragg angle during 5 ps. This is significantly shorter than the duration of the synchrotron x-ray pulse of 100 ps. Cross-correlation measurements of the ultrafast sample response and the synchrotron x-ray pulse allow to reconstruct the x-ray pulse shape.

  5. Ultrafast Charge Separation and Nongeminate Electron-Hole Recombination in Organic Photovoltaics

    E-Print Network [OSTI]

    Samuel L Smith; Alex W Chin

    2014-06-04

    The mechanism of electron-hole separation in organic solar cells is currently hotly debated. Recent experimental work suggests that these charges can separate on extremely short timescales (<100 fs). This can be understood in terms of delocalised transport within fullerene aggregates, which is thought to emerge on short timescales before vibronic relaxation induces polaron formation. However, in the optimal heterojunction morphology, electrons and holes will often re-encounter each other before reaching the electrodes. If such charges trap and cannot separate, then device efficiency will suffer. Here we extend the theory of ultrafast charge separation to incorporate polaron formation, and find that the same delocalised transport used to explain ultrafast charge separation can account for the suppression of nongeminate recombination in the best devices.

  6. Morphological changes in ultrafast laser ablation plumes with varying spot size

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Harilal, S. S.; Diwakar, P. K.; Polek, M. P.; Phillips, M. C.

    2015-06-04

    We investigated the role of spot size on plume morphology during ultrafast laser ablation of metal targets. Our results show that the spatial features of fs LA plumes are strongly dependent on the focal spot size. Two-dimensional self-emission images showed that the shape of the ultrafast laser ablation plumes changes from spherical to cylindrical with an increasing spot size from 100 to 600 ?m. The changes in plume morphology and internal structures are related to ion emission dynamics from the plasma, where broader angular ion distribution and faster ions are noticed for the smallest spot size used. The present resultsmore »clearly show that the morphological changes in the plume with spot size are independent of laser pulse width.« less

  7. Probing Ultrafast Dynamics with Time-resolved Multi-dimensional Coincidence Imaging: Butadiene

    E-Print Network [OSTI]

    Hockett, Paul; Rytwinski, Andrew; Stolow, Albert

    2013-01-01

    Time-resolved coincidence imaging of photoelectrons and photoions represents the most complete experimental measurement of ultrafast excited state dynamics, a multi-dimensional measurement for a multi-dimensional problem. Here we present the experimental data from recent coincidence imaging experiments, undertaken with the aim of gaining insight into the complex ultrafast excited-state dynamics of 1,3-butadiene initiated by absorption of 200 nm light. We discuss photoion and photoelectron mappings of increasing dimensionality, and focus particularly on the time-resolved photoelectron angular distributions (TRPADs), expected to be a sensitive probe of the electronic evolution of the excited state and to provide significant information beyond the time-resolved photoelectron spectrum (TRPES). Complex temporal behaviour is observed in the TRPADs, revealing their sensitivity to the dynamics while also emphasising the difficulty of interpretation of these complex observables. From the experimental data some details...

  8. Time of flight emission spectroscopy of laser produced nickel plasma: Short-pulse and ultrafast excitations

    SciTech Connect (OSTI)

    Smijesh, N.; Chandrasekharan, K. [Laser and Nonlinear Optics Laboratory, Department of Physics, National Institute of Technology Calicut, Calicut 673601 (India); Joshi, Jagdish C.; Philip, Reji, E-mail: reji@rri.res.in [Ultrafast and Nonlinear Optics Lab, Light and Matter Physics Group, Raman Research Institute, Bangalore 560080 (India)

    2014-07-07

    We report the experimental investigation and comparison of the temporal features of short-pulse (7 ns) and ultrafast (100 fs) laser produced plasmas generated from a solid nickel target, expanding into a nitrogen background. When the ambient pressure is varied in a large range of 10??Torr to 10²Torr, the plume intensity is found to increase rapidly as the pressure crosses 1 Torr. Time of flight (TOF) spectroscopy of emission from neutral nickel (Ni I) at 361.9 nm (3d?(²D) 4p ? 3d?(²D) 4s transition) reveals two peaks (fast and slow species) in short-pulse excitation and a single peak in ultrafast excitation. The fast and slow peaks represent recombined neutrals and un-ionized neutrals, respectively. TOF emission from singly ionized nickel (Ni II) studied using the 428.5 nm (3p?3d?(³P) 4s? 3p?3d? 4s) transition shows only a single peak for either excitation. Velocities of the neutral and ionic species are determined from TOF measurements carried out at different positions (i.e., at distances of 2 mm and 4 mm, respectively, from the target surface) on the plume axis. Measured velocities indicate acceleration of neutrals and ions, which is caused by the Coulomb pull of the electrons enveloping the plume front in the case of ultrafast excitation. Both Coulomb pull and laser-plasma interaction contribute to the acceleration in the case of short-pulse excitation. These investigations provide new information on the pressure dependent temporal behavior of nickel plasmas produced by short-pulse and ultrafast laser pulses, which have potential uses in applications such as pulsed laser deposition and laser-induced nanoparticle generation.

  9. Ablation experiment and threshold calculation of titanium alloy irradiated by ultra-fast pulse laser

    SciTech Connect (OSTI)

    Zheng, Buxiang; Jiang, Gedong; Wang, Wenjun Wang, Kedian; Mei, Xuesong; State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710054

    2014-03-15

    The interaction between an ultra-fast pulse laser and a material's surface has become a research hotspot in recent years. Micromachining of titanium alloy with an ultra-fast pulse laser is a very important research direction, and it has very important theoretical significance and application value in investigating the ablation threshold of titanium alloy irradiated by ultra-fast pulse lasers. Irradiated by a picosecond pulse laser with wavelengths of 1064 nm and 532 nm, the surface morphology and feature sizes, including ablation crater width (i.e. diameter), ablation depth, ablation area, ablation volume, single pulse ablation rate, and so forth, of the titanium alloy were studied, and their ablation distributions were obtained. The experimental results show that titanium alloy irradiated by a picosecond pulse infrared laser with a 1064 nm wavelength has better ablation morphology than that of the green picosecond pulse laser with a 532 nm wavelength. The feature sizes are approximately linearly dependent on the laser pulse energy density at low energy density and the monotonic increase in laser pulse energy density. With the increase in energy density, the ablation feature sizes are increased. The rate of increase in the feature sizes slows down gradually once the energy density reaches a certain value, and gradually saturated trends occur at a relatively high energy density. Based on the linear relation between the laser pulse energy density and the crater area of the titanium alloy surface, and the Gaussian distribution of the laser intensity on the cross section, the ablation threshold of titanium alloy irradiated by an ultra-fast pulse laser was calculated to be about 0.109 J/cm{sup 2}.

  10. Multidiagnostic analysis of ultrafast laser ablation of metals with pulse pair irradiation

    SciTech Connect (OSTI)

    Amoruso, S.; Bruzzese, R. [Dipartimento di Scienze Fisiche, Universita degli Studi di Napoli Federico II, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli (Italy); CNR-SPIN, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli (Italy); Wang, X. [CNR-SPIN, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli (Italy); O'Connell, G.; Lunney, J. G. [School of Physics, Trinity College-Dublin, Dublin 2 (Ireland)

    2010-12-01

    Copper targets are irradiated in the ablation regime by pairs of equal, time-delayed collinear laser pulses separated on a timescale going from {approx_equal}2 ps to {approx_equal}2 ns. The ablation plume is characterized by ion probe diagnostic, fast imaging, and temporally and spatially resolved optical emission spectroscopy. The variation in the ablation efficiency with the delay between the pulses is analyzed by measuring the ablation crater profile with a contact profilometer. The second laser pulse modifies the characteristics of the plasma plume produced by the first pulse and the ablation efficiency. The different mechanisms involved in double pulse ultrafast laser ablation are identified and discussed. The experimental findings are interpreted in the frame of a simple model of the interaction of the second pulse with the nascent ablation plume produced by the first pulse. This model yields consistent and quantitative agreement with the experimental findings predicting the observed experimental trends of the ablation depth reduction and ion yield increase with the delay between the pulses, as well as the characteristic timescale of the observed changes. The possibility of controlling the characteristics of the plumes produced during ultrafast laser ablation via an efficient coupling of the energy of the second pulse to the various ablation components produced by the first pulse is of particular interest in ultrafast pulsed laser deposition and microprobe analyses of materials.

  11. Processing and thermal properties of molecularly oriented polymers

    E-Print Network [OSTI]

    Skow, Erik (Erik Dean)

    2007-01-01

    High molecular weight polymers that are linear in molecular construction can be oriented such that some of their physical properties in the oriented direction are enhanced. For over 50 years polymer orientation and processing ...

  12. Interface-assisted molecular spintronics

    SciTech Connect (OSTI)

    Raman, Karthik V.

    2014-09-15

    Molecular spintronics, a field that utilizes the spin state of organic molecules to develop magneto-electronic devices, has shown an enormous scientific activity for more than a decade. But, in the last couple of years, new insights in understanding the fundamental phenomena of molecular interaction on magnetic surfaces, forming a hybrid interface, are presenting a new pathway for developing the subfield of interface-assisted molecular spintronics. The recent exploration of such hybrid interfaces involving carbon based aromatic molecules shows a significant excitement and promise over the previously studied single molecular magnets. In the above new scenario, hybridization of the molecular orbitals with the spin-polarized bands of the surface creates new interface states with unique electronic and magnetic character. This study opens up a molecular-genome initiative in designing new handles to functionalize the spin dependent electronic properties of the hybrid interface to construct spin-functional tailor-made devices. Through this article, we review this subject by presenting a fundamental understanding of the interface spin-chemistry and spin-physics by taking support of advanced computational and spectroscopy tools to investigate molecular spin responses with demonstration of new interface phenomena. Spin-polarized scanning tunneling spectroscopy is favorably considered to be an important tool to investigate these hybrid interfaces with intra-molecular spatial resolution. Finally, by addressing some of the recent findings, we propose novel device schemes towards building interface tailored molecular spintronic devices for applications in sensor, memory, and quantum computing.

  13. Introduction to Accelerated Molecular Dynamics

    SciTech Connect (OSTI)

    Perez, Danny [Los Alamos National Laboratory

    2012-07-10

    Molecular Dynamics is the numerical solution of the equations of motion of a set of atoms, given an interatomic potential V and some boundary and initial conditions. Molecular Dynamics is the largest scale model that gives unbiased dynamics [x(t),p(t)] in full atomistic detail. Molecular Dynamics: is simple; is 'exact' for classical dynamics (with respect to a given V); can be used to compute any (atomistic) thermodynamical or dynamical properties; naturally handles complexity -- the system does the right thing at the right time. The physics derives only from the interatomic potential.

  14. Physics Division annual review, April 1, 1988--March 31, 1989

    SciTech Connect (OSTI)

    Thayer, K.J.

    1989-08-01

    This document discusses the following main topics: Research at Atlas; Operation and Development of Atlas; Medium-Energy Nuclear Physics and Weak Interactions; Theoretical Nuclear Physics; Interactions of Fast Atomic and Molecular Ions with Solid and Gaseous Targets; Atomic Physics at Synchrotron Light Sources; Atomic Physics at Atlas and the ECR Source; Theoretical Atomic Physics; High-Resolution Laser-rf Spectroscopy of Atomic and Molecular Beams; and Fast Ion-Beam/Laser Studies of Atomic and Molecular Structure.

  15. Molecular fountain.

    SciTech Connect (OSTI)

    Strecker, Kevin E.; Chandler, David W.

    2009-09-01

    A molecular fountain directs slowly moving molecules against gravity to further slow them to translational energies that they can be trapped and studied. If the molecules are initially slow enough they will return some time later to the position from which they were launched. Because this round trip time can be on the order of a second a single molecule can be observed for times sufficient to perform Hz level spectroscopy. The goal of this LDRD proposal was to construct a novel Molecular Fountain apparatus capable of producing dilute samples of molecules at near zero temperatures in well-defined user-selectable, quantum states. The slowly moving molecules used in this research are produced by the previously developed Kinematic Cooling technique, which uses a crossed atomic and molecular beam apparatus to generate single rotational level molecular samples moving slowly in the laboratory reference frame. The Kinematic Cooling technique produces cold molecules from a supersonic molecular beam via single collisions with a supersonic atomic beam. A single collision of an atom with a molecule occurring at the correct energy and relative velocity can cause a small fraction of the molecules to move very slowly vertically against gravity in the laboratory. These slowly moving molecules are captured by an electrostatic hexapole guiding field that both orients and focuses the molecules. The molecules are focused into the ionization region of a time-of-flight mass spectrometer and are ionized by laser radiation. The new molecular fountain apparatus was built utilizing a new design for molecular beam apparatus that has allowed us to miniaturize the apparatus. This new design minimizes the volumes and surface area of the machine allowing smaller pumps to maintain the necessary background pressures needed for these experiments.

  16. The Behavior of Hydrogen Under Extreme Conditions on Ultrafast Timescales (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

    ScienceCinema (OSTI)

    Mao, Ho-kwang (Director, Center for Energy Frontier Research in Extreme Environments); EFree Staff

    2011-11-02

    'The Behavior of Hydrogen Under Extreme Conditions on Ultrafast Timescales ' was submitted by the Center for Energy Frontier Research in Extreme Environments (EFree) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. EFree is directed by Ho-kwang Mao at the Carnegie Institute of Washington and is a partnership of scientists from thirteen institutions.The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of Energy Frontier Research in Extreme Environments is 'to accelerate the discovery and creation of energy-relevant materials using extreme pressures and temperatures.' Research topics are: catalysis (CO{sub 2}, water), photocatalysis, solid state lighting, optics, thermelectric, phonons, thermal conductivity, solar electrodes, fuel cells, superconductivity, extreme environment, radiation effects, defects, spin dynamics, CO{sub 2} (capture, convert, store), greenhouse gas, hydrogen (fuel, storage), ultrafast physics, novel materials synthesis, and defect tolerant materials.

  17. Ultra-fast outflows (aka UFOs) from AGNs and QSOs

    E-Print Network [OSTI]

    Cappi, M; Giustini, M

    2013-01-01

    During the last decade, strong observational evidence has been accumulated for the existence of massive, high velocity winds/outflows (aka Ultra Fast Outflows, UFOs) in nearby AGNs and in more distant quasars. Here we briefly review some of the most recent developments in this field and discuss the relevance of UFOs for both understanding the physics of accretion disk winds in AGNs, and for quantifying the global amount of AGN feedback on the surrounding medium.

  18. Molecular Foundry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Lab; Professor of Physics UC Berkeley 66 Auditorium 9:30 am Keynote Address The BRAIN Initiative and Nanoscience abstract Ralph Greenspan Director, Center for Brain...

  19. Production of high molecular weight polylactic acid

    DOE Patents [OSTI]

    Bonsignore, Patrick V. (Joilet, IL)

    1995-01-01

    A degradable high molecular weight poly(lactic acid). A poly(lactic acid) has a terminal end group of one of carboxyl or hydroxyl groups with low molecular weight poly(lactic acid) units coupled with linking agents of di-isocyanates, bis-epoxides, bis-oxazolines and bis-ortho esters. The resulting high molecular weight poly(lactic acid) can be used for applications taking advantage of the improved physical properties.

  20. Production of high molecular weight polylactic acid

    DOE Patents [OSTI]

    Bonsignore, P.V.

    1995-11-28

    A degradable high molecular weight poly(lactic acid) is described. The poly(lactic acid) has a terminal end group of one of carboxyl or hydroxyl groups with low molecular weight poly(lactic acid) units coupled with linking agents of di-isocyanates, bis-epoxides, bis-oxazolines and bis-ortho esters. The resulting high molecular weight poly(lactic acid) can be used for applications taking advantage of the improved physical properties.

  1. Physics 630 Statistical Physics

    E-Print Network [OSTI]

    Kioussis, Nicholas

    strongly the issue of problem solving and understanding of the main concepts in Statistical PhysicsPhysics 630 Statistical Physics Spring 2005 Logistics Lecture Room: 1100 (Science I, 1st floor (Supplement) Introduction to Modern Statistical Mechanics, by David Chandler, Oxford Objectives This course

  2. Physics Division annual review, April 1, 1991--March 31, 1992

    SciTech Connect (OSTI)

    Henning, W.F.

    1992-08-01

    This report contains brief discusses on topics in the following areas: Research at atlas; operation and development of atlas; medium-energy nuclear physics and weak interactions; theoretical nuclear physics; and atomic and molecular physics research.

  3. List of Examiners for MVMod MASTER of Science in Physics

    E-Print Network [OSTI]

    Heermann, Dieter W.

    List of Examiners for MVMod MASTER of Science in Physics Astronomy and Astrophysics: Bartelmann, Quirrenbach, Rix, Schaefer, Springel, Spurzem, Wagner, Wambsganß Atomic, Molecular and Optical Physics: Blaum, Schlichting, Schwarz, Spatz, Tanaka Condensed Matter Physics: Enss, Klingeler, Kowalsky, Pucci, Winnacker

  4. From gyroscopic to thermal motion: a crossover in the dynamics of molecular superrotors

    E-Print Network [OSTI]

    Milner, A A; Rezaiezadeh, K; Milner, V

    2015-01-01

    Localized heating of a gas by intense laser pulses leads to interesting acoustic, hydrodynamic and optical effects with numerous applications in science and technology, including controlled wave guiding and remote atmosphere sensing. Rotational excitation of molecules can serve as the energy source for raising the gas temperature. Here, we study the dynamics of energy transfer from the molecular rotation to heat. By optically imaging a cloud of molecular superrotors, created with an optical centrifuge, we experimentally identify two separate and qualitatively different stages of its evolution. The first non-equilibrium "gyroscopic" stage is characterized by the modified optical properties of the centrifuged gas - its refractive index and optical birefringence, owing to the ultrafast directional molecular rotation, which survives tens of collisions. The loss of rotational directionality is found to overlap with the release of rotational energy to heat, which triggers the second stage of thermal expansion. The ...

  5. Single Photon Subradiance:Quantum control of spontaneous emission and ultrafast readout

    E-Print Network [OSTI]

    Marlan O. Scully

    2015-05-12

    Recent work has shown that collective single photon emission from an ensemble of resonate two-level atoms is a rich field of study. For example single photon superradiance from an extended ensemble yields enhanced directional spontaneous emission; and when the effects of the collective Lamb shift are included it becomes even more interesting. The present paper addresses the flip side of superradiance, i.e., subradiance. Single photon subradiant states are potentially stable against collective spontaneous emission and can have ultrafast readout. In particular, it is shown how many atom collective effects can be used to control emission by preparing and switching between subradiant and superradiant states.

  6. Ultrafast dynamics of liquid water: Frequency fluctuations of the OH stretch and the HOH bend

    SciTech Connect (OSTI)

    Imoto, Sho; Xantheas, Sotiris S.; Saito, Shinji

    2013-07-28

    Frequency fluctuations of the OH stretch and the HOH bend in liquid water are reported from the third-order response function evaluated using the TTM3-F potential for water. The simulated two-dimensional infrared (IR) spectra of the OH stretch are similar to previously reported theoretical results. The present study suggests that the frequency fluctuation of the HOH bend is faster than that of the OH stretch. The ultrafast loss of the frequency correlation of the HOH bend is due to the strong couplings with the OH stretch as well as the intermolecular hydrogen bond bend.

  7. Ultrafast spectroscopy of super high frequency mechanical modes of doubly clamped beams

    SciTech Connect (OSTI)

    Ristow, Oliver; Merklein, Moritz; Grossmann, Martin; Hettich, Mike; Schubert, Martin; Bruchhausen, Axel; Scheer, Elke; Dekorsy, Thomas; Barretto, Elaine C. S.; Grebing, Jochen; Erbe, Artur; Mounier, Denis; Gusev, Vitalyi

    2013-12-02

    We use ultrafast pump-probe spectroscopy to study the mechanical vibrations in the time domain of doubly clamped silicon nitride beams. Beams with two different clamping conditions are investigated. Finite element method calculations are performed to analyse the mode spectra of both structures. By calculating the strain integral on the surface of the resonators, we are able to reproduce the effect of the detection mechanism and identify all the measured modes. We show that our spectroscopy technique combined with our modelling tools allow the investigation of several different modes in the super high frequency range (3-30?GHz) and above, bringing more information about the vibration modes of nanomechanical resonators.

  8. Measurements of Ionic Structure in Shock Compressed Lithium Hydride from Ultrafast X-Ray Thomson Scattering

    SciTech Connect (OSTI)

    Kritcher, A. L. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Department of Nuclear Engineering, University of California Berkeley, Berkeley, California 94709 (United States); Neumayer, P.; Doeppner, T.; Landen, O. L.; Glenzer, S. H. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Brown, C. R. D. [Department of Physics, Imperial College, London SW7 2AZ (United Kingdom); AWE plc., Aldermaston, Reading, RG7 4PR (United Kingdom); Davis, P. [L-399, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Department of Physics, University of California Berkeley, Berkeley, California 94709 (United States); Falcone, R. W.; Lee, H. J. [Department of Physics, University of California Berkeley, Berkeley, California 94709 (United States); Gericke, D. O.; Vorberger, J.; Wuensch, K. [CFSA, Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Gregori, G. [Department of Physics, Oxford University, Oxford OX1 3PU (United Kingdom); Holst, B.; Redmer, R. [Universitaet Rostock, Institut fuer Physik, D-18051 Rostock (Germany); Morse, E. C. [Department of Nuclear Engineering, University of California Berkeley, Berkeley, California 94709 (United States); Pelka, A.; Roth, M. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Darmstadt (Germany)

    2009-12-11

    We present the first ultrafast temporally, spectrally, and angularly resolved x-ray scattering measurements from shock-compressed matter. The experimental spectra yield the absolute elastic and inelastic scattering intensities from the measured density of free electrons. Laser-compressed lithium-hydride samples are well characterized by inelastic Compton and plasmon scattering of a K-alpha x-ray probe providing independent measurements of temperature and density. The data show excellent agreement with the total intensity and structure when using the two-species form factor and accounting for the screening of ion-ion interactions.

  9. Differential ultrafast all-optical switching of the resonances of a micropillar cavity

    SciTech Connect (OSTI)

    Thyrrestrup, Henri Yüce, Emre; Ctistis, Georgios; Vos, Willem L.; Claudon, Julien; Gérard, Jean-Michel

    2014-09-15

    We perform frequency- and time-resolved all-optical switching of a GaAs-AlAs micropillar cavity using an ultrafast pump-probe setup. The switching is achieved by two-photon excitation of free carriers. We track the cavity resonances in time with a high frequency resolution. The pillar modes exhibit simultaneous frequency shifts, albeit with markedly different maximum switching amplitudes and relaxation dynamics. These differences stem from the non-uniformity of the free carrier density in the micropillar, and are well understood by taking into account the spatial distribution of injected free carriers, their spatial diffusion and surface recombination at micropillar sidewalls.

  10. An ultrafast phase-change logic device driven by melting processes

    E-Print Network [OSTI]

    Loke, D.; Skelton, J. M.; Wang, W. J.; Lee, T. H.; Zhao, R.; Chong, T. C.; Elliott, S. R.

    2014-09-02

    augmented-wave (PAW) method (36), with the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional (37), was used. The GST models were simulated in cubic supercells with periodic boundary conditions. The plane-wave energy cutoff was 174.98 eV. All... /device structures are developed with a higher number of resistance levels and resistance-level combinations (11,14). 6 The GST cells have been shown to exhibit ultra-fast Boolean algebraic operations via boosting the energy delivered by electrical...

  11. Ultrafast Probes for Dirac Materials (Technical Report) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaon and(Conference) |Article) |Fe(phen) 2 (NCS) 2Ultrafast Probes for

  12. Quantum logic with molecular ions

    E-Print Network [OSTI]

    Wolf, Fabian; Heip, Jan C; Gebert, Florian; Shi, Chunyan; Schmidt, Piet O

    2015-01-01

    Laser spectroscopy of cold and trapped molecular ions is a powerful tool for fundamental physics, including the determination of fundamental constants, the laboratory test for their possible variation, and the search for a possible electric dipole moment of the electron. Optical clocks based on molecular ions sensitive to some of these effects are expected to achieve uncertainties approaching the $10^{-18}$ level. While the complexity of molecular structure facilitates these applications, the absence of cycling transitions poses a challenge for direct laser cooling, quantum state control, and detection. Previously employed state detection techniques based on photo-dissociation or chemical reactions are destructive and therefore inefficient. Here we experimentally demonstrate non-destructive state detection of a single trapped molecular ion through its strong Coulomb coupling to a well-controlled co-trapped atomic ion. An algorithm based on a state-dependent optical dipole force(ODF) changes the internal state...

  13. Explosive photodissociation of methane induced by ultrafast intense laser

    SciTech Connect (OSTI)

    Kong Fanao; Luo Qi; Xu Huailiang; Sharifi, Mehdi; Song Di; Chin, See Leang

    2006-10-07

    A new type of molecular fragmentation induced by femtosecond intense laser at the intensity of 2x10{sup 14} W/cm{sup 2} is reported. For the parent molecule of methane, ethylene, n-butane, and 1-butene, fluorescence from H (n=3{yields}2), CH (A {sup 2}{delta}, B {sup 2}{sigma}{sup -}, and C {sup 2}{sigma}{sup +}{yields}X {sup 2}{pi}), or C{sub 2} (d {sup 3}{pi}{sub g}{yields}a {sup 3}{pi}{sub u}) is observed in the spectrum. It shows that the fragmentation is a universal property of neutral molecule in the intense laser field. Unlike breaking only one or two chemical bonds in conventional UV photodissociation, the fragmentation caused by the intense laser undergoes vigorous changes, breaking most of the bonds in the molecule, like an explosion. The fragments are neutral species and cannot be produced through Coulomb explosion of multiply charged ion. The laser power dependence of CH (A{yields}X) emission of methane on a log-log scale has a slope of 10{+-}1. The fragmentation is thus explained as multiple channel dissociation of the superexcited state of parent molecule, which is created by multiphoton excitation.

  14. Molecular Physics 2012, 110, iFirst

    E-Print Network [OSTI]

    Moiseyev, Nimrod

    H. MILLER Resonance energies, lifetimes and complex energy potential curves from standard wave at the Technion-Israel Institute of Technology, Haifa, 32000, Israel (Received 1 December 2011; final version obtain the resonance energies and lifetimes as well as their corresponding eigenfunctions it is possible

  15. Ultrafast dynamics of strong-field dissociative ionization ofCH2Br2 probed by femtosecond soft x-ray transient absorptionspectroscopy

    SciTech Connect (OSTI)

    Loh, Zhi-Heng; Leone, Stephen R.

    2008-01-15

    Femtosecond time-resolved soft x-ray transient absorption spectroscopy based on a high-order harmonic generation source is used to investigate the dissociative ionization of CH{sub 2}Br{sub 2} induced by 800 nm strong-field irradiation. At moderate peak intensities (2.0 x 10{sup 14} W/cm{sup 2}), strong-field ionization is accompanied by ultrafast C-Br bond dissociation, producing both neutral Br ({sup 2}P{sub 3/2}) and Br* ({sup 2}P{sub 1/2}) atoms together with the CH{sub 2}Br{sup +} fragment ion. The measured rise times for Br and Br* are 130 {+-} 22 fs and 74 {+-} 10 fs, respectively. The atomic bromine quantum state distribution shows that the Br/Br* population ratio is 8.1 {+-} 3.8 and that the Br {sup 2}P{sub 3/2} state is not aligned. The observed product distribution and the timescales of the photofragment appearances suggest that multiple field-dressed potential energy surfaces are involved in the dissociative ionization process. In addition, the transient absorption spectrum of CH{sub 2}Br{sub 2}{sup +} suggests that the alignment of the molecule relative to the polarization axis of the strong-field ionizing pulse determines the electronic symmetry of the resulting ion; alignment of the Br-Br, H-H, and C{sub 2} axis of the molecule along the polarization axis results in the production of the ion {tilde X}({sup 2}B{sub 2}), {tilde B}({sup 2}B{sub 1}) and {tilde C}({sup 2}A{sub 1}) states, respectively. At higher peak intensities (6.2 x 10{sup 14} W/cm{sup 2}), CH{sub 2}Br{sub 2}{sup +} undergoes sequential ionization to form the metastable CH{sub 2}Br{sub 2}{sup 2+} dication. These results demonstrate the potential of core-level probing with high-order harmonic transient absorption spectroscopy for studying ultrafast molecular dynamics.

  16. Controlling Graphene Ultrafast Hot Carrier Response from Metal-like to Semiconductor-like by Electrostatic Gating

    E-Print Network [OSTI]

    Zettl, Alex

    with dry nitrogen during the measurement. Sample preparation We grow single layer graphene on copper foil1 Controlling Graphene Ultrafast Hot Carrier Response from Metal-like to Semiconductor electro-optic sampling.2 The focused THz beam at our graphene sample has a diameter of 1 mm. For optical

  17. Ultrafast Microfluidic Mixer and Freeze-Quenching Yu Lin, Gary J. Gerfen, Denis L. Rousseau, and Syun-Ru Yeh*

    E-Print Network [OSTI]

    Yeh, Syun-Ru

    Ultrafast Microfluidic Mixer and Freeze-Quenching Device Yu Lin, Gary J. Gerfen, Denis L. Rousseau fluids. To overcome these problems, we have designed and tested a novel microfluidic silicon mixer. The mixed-solution jet, with a cross section of 10 µm × 100 µm, exits from the microfluidic silicon mixer

  18. H.sub.2O doped WO.sub.3, ultra-fast, high-sensitivity hydrogen sensors

    DOE Patents [OSTI]

    Liu, Ping (Denver, CO); Tracy, C. Edwin (Golden, CO); Pitts, J. Roland (Lakewood, CO); Lee, Se-Hee (Lakewood, CO)

    2011-03-22

    An ultra-fast response, high sensitivity structure for optical detection of low concentrations of hydrogen gas, comprising: a substrate; a water-doped WO.sub.3 layer coated on the substrate; and a palladium layer coated on the water-doped WO.sub.3 layer.

  19. Hydrogen Bond Switching among Flavin and Amino Acid Side Chains in the BLUF Photoreceptor Observed by Ultrafast Infrared Spectroscopy

    E-Print Network [OSTI]

    van Stokkum, Ivo

    Hydrogen Bond Switching among Flavin and Amino Acid Side Chains in the BLUF Photoreceptor Observed hydrogen-bond network with nearby amino acid side chains, including a highly conserved tyrosine and glutamine. The participation of particular amino acid side chains in the ultrafast hydrogen-bond switching

  20. Ultrafast Laser Pulse Control of Exciton Dynamics: A Computational Study on the FMO Ben Bru1ggemann and Volkhard May*

    E-Print Network [OSTI]

    Röder, Beate

    Ultrafast Laser Pulse Control of Exciton Dynamics: A Computational Study on the FMO Complex Ben Bru, D-12489 Berlin, Germany ReceiVed: February 4, 2004; In Final Form: May 23, 2004 Femtosecond laser-pulse on the Frenkel exciton model for the bacteriochlorophyll (BChl) Qy-excitations, the laser- pulse-driven exciton

  1. Modeling and Technologies of Ultrafast Fiber Lasers Brandon G. Bale, Oleg G. Okhitnikov, and Sergei K. Turitsyn

    E-Print Network [OSTI]

    Turitsyn, Sergei K.

    for simplicity, maintenance, and reliability, however, have not been met by conventional ultrafast technology with reliable and cost- effective components, which makes suitably designed fiber lasers real contenders many alignment issues, it also distributes heat generated by optical pumping over the length

  2. Controlling Graphene Ultrafast Hot Carrier Response from Metal-like to Semiconductor-like by Electrostatic Gating

    E-Print Network [OSTI]

    Zettl, Alex

    1 Controlling Graphene Ultrafast Hot Carrier Response from Metal-like to Semiconductor electro-optic sampling.2 The focused THz beam at our graphene sample has a diameter of 1 mm. For optical between optical pump and THz probe. We use ion-gel gating to control the carrier concentration in graphene

  3. Controlling Graphene Ultrafast Hot Carrier Response from Metal-like to Semiconductor-like by Electrostatic Gating

    E-Print Network [OSTI]

    Wang, Feng

    Controlling Graphene Ultrafast Hot Carrier Response from Metal-like to Semiconductor neutral graphene but decreases in highly doped graphene. We show that this transition from semiconductor graphene upon optical excitation. We observe that the photoinduced terahertz absorption increases in charge

  4. PUBLISHED ONLINE: 10 JANUARY 2010 | DOI: 10.1038/NPHYS1498 Ultrafast energy transfer between water molecules

    E-Print Network [OSTI]

    Loss, Daniel

    -called water dimer). This intermolecular coulombic decay leads to an ejection of a low-energy electron from and leads to dissociation of the water dimer into two H2O+ ions. As electrons of low energy (0.7-20 eV) haveLETTERS PUBLISHED ONLINE: 10 JANUARY 2010 | DOI: 10.1038/NPHYS1498 Ultrafast energy transfer

  5. Ultrafast UV Pump/IR Probe Studies of C-H Activation in Linear, Cyclic, and Aryl Hydrocarbons

    E-Print Network [OSTI]

    Harris, Charles B.

    Ultrafast UV Pump/IR Probe Studies of C-H Activation in Linear, Cyclic, and Aryl Hydrocarbons, cyclic, and aromatic hydrocarbon solvents on a femtosecond to microsecond time scale. These results have revealed that the structure of the hydrocarbon substrate affects the final C-H bond activation step, which

  6. The UFFO (Ultra-Fast Flash Observatory) Pathfinder

    E-Print Network [OSTI]

    Park, I H; Lim, H; Nam, J W; Chen, Pisin; Khrenov, B A; Kim, Y -K; Lee, C -H; Lee, J; Linder, E V; Panasyuk, M; Park, J H; Smoot, G F; Uhm, Z L

    2009-01-01

    Hundreds of gamma-ray burst (GRB) UV-optical light curves have been measured since the discovery of optical afterglows, however, even after nearly 5 years of operation of the SWIFT observatory, only a handful of measurements have been made soon (within a minute) after the gamma ray signal. This lack of early observations fails to address burst physics at the short time scales associated with burst events and progenitors. Because of this lack of sub-minute data, the characteristics of the UV-optical light curve of short-hard type GRB and rapid-rising GRB, which may account for ~30% of all GRB, remain practically unknown. We have developed methods for reaching the sub-minute and the sub-second timescales in a small spacecraft observatory appropriate for launch on a microsatellite. Rather than slewing the entire spacecraft to aim the UV-optical instrument at the GRB position, we use rapidly moving mirrors to redirect our optical beam. Our collaboration has produced a unique MEMS (microelectromechanical systems) ...

  7. DEPARTMENT OF PHYSICS Physics 32100

    E-Print Network [OSTI]

    Brinkmann, Peter

    DEPARTMENT OF PHYSICS Syllabus Physics 32100 Modern Physics for Engineers Designation to one- electron atoms, atomic shell structure and periodic table; nuclear physics, relativity. Prerequisites: Prereq.: Physics 20800 or equivalent, Math 20300 or 20900 (elective for Engineering students

  8. DEPARTMENT OF PHYSICS Physics 21900

    E-Print Network [OSTI]

    Brinkmann, Peter

    DEPARTMENT OF PHYSICS Syllabus Physics 21900 Physics for Architecture Students Designation suggested material: Giancoli, Physics, Principles with Applications (6th ed.) (required), Prentice Hall Giancoli, Physics, Principles with Applications, Student Guide (6th ed.) (optional), Prentice Hall Course

  9. DEPARTMENT OF PHYSICS Physics 20300

    E-Print Network [OSTI]

    Brinkmann, Peter

    DEPARTMENT OF PHYSICS Syllabus Physics 20300 General Physics Designation: Required Undergraduate Catalog description: For majors in the life sciences (biology, medicine, dentistry, psychology, physical therapy) and for liberal arts students. Fundamental ideas and laws of physics from mechanics to modern

  10. Molecular Dynameomics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJessework uses concrete7Modifications for Public CommentDynameomics Molecular

  11. PHYSICAL CHANGES IN THE PORE STRUCTURE OF COAL WITH CHEMICAL PROCESSING

    E-Print Network [OSTI]

    Harris Jr, E.C.

    2011-01-01

    Physical Properties of Extracted Coals A. B. Introduction.IV. PHYSICAL PROPERTIES OF EXTRACTED COALS A. Introductionthe molecular sieve properties of coal to determine a rough

  12. A 64-channel personal computer based image reconstruction system and applications in single echo acquisition magnetic resonance elastography and ultra-fast magnetic resonance imaging. 

    E-Print Network [OSTI]

    Yallapragada, Naresh

    2009-05-15

    Emerging technologies in parallel magnetic resonance imaging (MRI) with massive receiver arrays have paved the way for ultra-fast imaging at increasingly high frame rates. With the increase in the number of receiver channels ...

  13. Effective Analysis of NGS Metagenomic Data with Ultra-Fast Clustering Algorithms (MICW - Metagenomics Informatics Challenges Workshop: 10K Genomes at a Time)

    ScienceCinema (OSTI)

    Li, Weizhong [San Diego Supercomputer Center

    2013-01-22

    San Diego Supercomputer Center's Weizhong Li on "Effective Analysis of NGS Metagenomic Data with Ultra-fast Clustering Algorithms" at the Metagenomics Informatics Challenges Workshop held at the DOE JGI on October 12-13, 2011.

  14. Frontiers for Discovery in High Energy Density Physics

    SciTech Connect (OSTI)

    Davidson, R. C.; Katsouleas, T.; Arons, J.; Baring, M.; Deeney, C.; Di Mauro, L.; Ditmire, T.; Falcone, R.; Hammer, D.; Hill, W.; Jacak, B.; Joshi, C.; Lamb, F.; Lee, R.; Logan, B. G.; Melissinos, A.; Meyerhofer, D.; Mori, W.; Murnane, M.; Remington, B.; Rosner, R.; Schneider, D.; Silvera, I.; Stone, J.; Wilde, B.; Zajc. W.

    2004-07-20

    The report is intended to identify the compelling research opportunities of high intellectual value in high energy density physics. The opportunities for discovery include the broad scope of this highly interdisciplinary field that spans a wide range of physics areas including plasma physics, laser and particle beam physics, nuclear physics, astrophysics, atomic and molecular physics, materials science and condensed matter physics, intense radiation-matter interaction physics, fluid dynamics, and magnetohydrodynamics

  15. Ultrafast Control of Magnetism in Ferromagnetic Semiconductors via Photoexcited Transient Carriers

    SciTech Connect (OSTI)

    Cotoros, Ingrid A.

    2008-12-12

    The field of spintronics offers perspectives for seamless integration of coupled and inter-tunable electrical and magnetic properties in a single device. For integration of the spin degree of freedom with current electronic technology, new semiconductors are needed that show electrically-tunable magnetic properties at room temperature and above. Dilute magnetic semiconductors derived from III-V compounds, like GaMnAs and InMnAs, show coupled and tunable magnetic, transport, and optical properties, due to the fact that their ferromagnetism is hole-mediated. These unconventional materials are ideal systems for manipulating the magnetic order by changing the carrier polarization, population density, and energy band distribution of the complementary subsystem of holes. This is the main theme we cover in this thesis. In particular, we develop a unique setup by use of ultraviolet pump, near-infrared probe femtosecond laser pulses, that allows for magneto-optical Kerr effect (MOKE) spectroscopy experiments. We photo-excite transient carriers in our samples, and measure the induced transient magnetization dynamics. One set of experiments performed allowed us to observe for the first time enhancement of the ferromagnetic order in GaMnAs, on an ultrafast time scale of hundreds of picoseconds. The corresponding transient increase of Curie temperature (Tc, the temperature above which a ferromagnetic material loses its permanent magnetism) of about 1 K for our experimental conditions is a very promising result for potential spintronics applications, especially since it is seconded by observation of an ultrafast ferromagnetic to paramagnetic phase transition above Tc. In a different set of experiments, we"write" the magnetization in a particular orientation in the sample plane. Using an ultrafast scheme, we alter the distribution of holes in the system and detect signatures of the particular memory state in the subsequent magnetization dynamics, with unprecedented hundreds of femtosecond detection speed. The femtosecond cooperative magnetic phenomena presented here further our understanding of Mn-hole correlations in III-V dilute magnetic semiconductors, and may well represent universal principles of a large class of carrier-mediated ferromagnetic materials. Thus they offer perspectives for future terahertz (1012 Hz) speed"spintronic" functional devices.

  16. Chirped-pulse manipulated carrier dynamics in low-temperature molecular-beam-epitaxy grown GaAs

    SciTech Connect (OSTI)

    Lee, Chao-Kuei, E-mail: chuckcklee@yahoo.com [Department of Photonics, National Sun-Yat-Sen University, Kaohsiung 80400, Taiwan (China); Lin, Yuan-Yao [Department of Electrical Engineering, Institute of Photonics Technologies, National Tsing Hua University, Hsinchu 30010, Taiwan (China); Lin, Sung-Hui [Department of Photonics, National Chiao Tung University, Hsinchu 30010, Taiwan (China); Lin, Gong-Ru [Department of Electrical Engineering, Graduate Institute of Photonics and Optoelectronics, National Taiwan University, No. 1, Roosevelt Road, Sec. 4, Taipei 10617, Taiwan (China); Pan, Ci-Ling [Department of Photonics, National Chiao Tung University, Hsinchu 30010, Taiwan (China); Department of Physics, National Tsing Hwa University, Hsinchu 30010, Taiwan (China)

    2014-04-28

    Chirped pulse controlled carrier dynamics in low-temperature molecular-beam-epitaxy grown GaAs are investigated by degenerate pump-probe technique. Varying the chirped condition of excited pulse from negative to positive increases the carrier relaxation time so as to modify the dispersion and reshape current pulse in time domain. The spectral dependence of carrier dynamics is analytically derived and explained by Shockley-Read Hall model. This observation enables the new feasibility of controlling carrier dynamics in ultrafast optical devices via the chirped pulse excitations.

  17. Molecular separation method and apparatus

    DOE Patents [OSTI]

    Villa-Aleman, Eliel (3108 Roses Run, Aiken, SC 29803)

    1996-01-01

    A method and apparatus for separating a gaseous mixture of chemically identical but physically different molecules based on their polarities. The gaseous mixture of molecules is introduced in discrete quantities into the proximal end of a porous glass molecular. The molecular sieve is exposed to microwaves to excite the molecules to a higher energy state from a lower energy state, those having a higher dipole moment being excited more than those with a lower energy state. The temperature of the sieve kept cold by a flow of liquid nitrogen through a cooling jacket so that the heat generated by the molecules colliding with the material is transferred away from the material. The molecules thus alternate between a higher energy state and a lower one, with the portion of molecules having the higher dipole moment favored over the others. The former portion can then be extracted separately from the distal end of the molecular sieve.

  18. Ultra-fast heralded single photon source based on telecom technology

    E-Print Network [OSTI]

    Lutfi Arif Ngah; Olivier Alibart; Laurent Labonté; Virginia D'Auria; Sébastien Tanzilli

    2014-12-17

    The realization of an ultra-fast source of heralded single photons emitted at the wavelength of 1540 nm is reported. The presented strategy is based on state-of-the-art telecom technology, combined with off-the-shelf fiber components and waveguide non-linear stages pumped by a 10 GHz repetition rate laser. The single photons are heralded at a rate as high as 2.1 MHz with a heralding efficiency of 42%. Single photon character of the source is inferred by measuring the second-order autocorrelation function. For the highest heralding rate, a value as low as 0.023 is found. This not only proves negligible multi-photon contributions but also represents the best measured value reported to date for heralding rates in the MHz regime. These prime performances, associated with a device-like configuration, are key ingredients for both fast and secure quantum communication protocols.

  19. Ultrafast gated intensifier design for laser fusion x-ray framing applications

    SciTech Connect (OSTI)

    Price, R.H.; Wiedwald, J.D.; Kalibjian, R.; Thomas, S.W.; Cook, W.M.

    1983-11-01

    A major challenge for laser fusion is the study of the symmetry and the hydrodynamic stability of imploding fuel capsules. Streaked x-radiography, in one space and one time dimension, does not provide sufficient information. Two (spatial) dimensional frames of 10 to 100 ps duration are required with good image quality, minimum geometrical distortion (approximately 1%), dynamic range greater than 1000 and greater than 200 x 200 pixels. A gated transmission line imager (TLI) can meet these requirements with frame times between 30 and 100 ps. An instrument of this type is now being developed. Progress on this instrument including theory of operation, ultrafast pulse generation and propagation, component integration, and high resolution phosphor screen development are presented.

  20. Phonon-Assisted Ultrafast Charge Separation in a Realistic PCBM Aggregate

    E-Print Network [OSTI]

    Samuel L. Smith; Alex W. Chin

    2014-06-25

    Organic solar cells must separate strongly bound electron-hole pairs into free charges. This is achieved at interfaces between electron donor and acceptor organic semiconductors. The most popular electron acceptor is the fullerene derivative PCBM. Electron-hole separation has been observed on femtosecond timescales, which is incompatible with conventional Marcus theories of organic transport. In this work we show that ultrafast charge transport in PCBM arises from its broad range of electronic eigenstates, provided by the presence of three closely spaced delocalised bands near the LUMO level. Vibrational fluctuations enable rapid transitions between these bands, which drives an electron transport of $\\sim$3 nm within 100 fs. All this is demonstrated within a realistic tight binding Hamiltonian containing transfer integrals no larger than 8 meV.

  1. Ultrafast myoglobin structural dynamics observed with an X-ray free-electron laser

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Levantino, Matteo; Schirò, Giorgio; Lemke, Henrik Till; Cottone, Grazia; Glownia, James Michael; Zhu, Diling; Chollet, Mathieu; Ihee, Hyotcherl; KAIST, Daejeon; Cupane, Antonio; et al

    2015-04-02

    Light absorption can trigger biologically relevant protein conformational changes. The light induced structural rearrangement at the level of a photoexcited chromophore is known to occur in the femtosecond timescale and is expected to propagate through the protein as a quake-like intramolecular motion. Here we report direct experimental evidence of such ‘proteinquake’ observed in myoglobin through femtosecond X-ray solution scattering measurements performed at the Linac Coherent Light Source X-ray free-electron laser. An ultrafast increase of myoglobin radius of gyration occurs within 1 picosecond and is followed by a delayed protein expansion. As the system approaches equilibrium it undergoes damped oscillations withmore »a ~3.6-picosecond time period. Our results unambiguously show how initially localized chemical changes can propagate at the level of the global protein conformation in the picosecond timescale.« less

  2. Ultrafast terahertz-induced response of GeSbTe phase-change materials

    SciTech Connect (OSTI)

    Shu, Michael J.; Zalden, Peter; Chen, Frank; Weems, Ben; Chatzakis, Ioannis; Xiong, Feng; Jeyasingh, Rakesh; Pop, Eric; Philip Wong, H.-S.; Hoffmann, Matthias C.; Wuttig, Matthias; Lindenberg, Aaron M.

    2014-06-23

    The time-resolved ultrafast electric field-driven response of crystalline and amorphous GeSbTe films has been measured all-optically, pumping with single-cycle terahertz pulses as a means of biasing phase-change materials on a sub-picosecond time-scale. Utilizing the near-band-gap transmission as a probe of the electronic and structural response below the switching threshold, we observe a field-induced heating of the carrier system and resolve the picosecond-time-scale energy relaxation processes and their dependence on the sample annealing condition in the crystalline phase. In the amorphous phase, an instantaneous electroabsorption response is observed, quadratic in the terahertz field, followed by field-driven lattice heating, with Ohmic behavior up to 200?kV/cm.

  3. Efficient terahertz-wave generation and its ultrafast optical modulation in charge ordered organic ferroelectrics

    SciTech Connect (OSTI)

    Itoh, Hirotake Iwai, Shinichiro; Itoh, Keisuke; Goto, Kazuki; Yamamoto, Kaoru; Yakushi, Kyuya

    2014-04-28

    Efficient terahertz (THz) wave generation in strongly correlated organic compounds ?-(ET){sub 2}I{sub 3} and ??-(ET){sub 2}IBr{sub 2} (ET:bis(ethylenedithio)-tetrathiafulvalene) was demonstrated. The spontaneous polarization induced by charge ordering or electronic ferroelectricity was revealed to trigger the THz-wave generation via optical rectification; the estimated 2nd-order nonlinear optical susceptibility for ?-(ET){sub 2}I{sub 3} is over 70 times larger than that for prototypical THz-source ZnTe. Ultrafast (<1 ps) and sensitive (?40%) photoresponse of the THz wave was observed for ?-(ET){sub 2}I{sub 3}, which is attributable to photoinduced quenching of the polarization accompanied by insulator(ferroelectric)-to-metal transition. Modulation of the THz wave was observed for ??-(ET){sub 2}IBr{sub 2} upon the poling procedure, indicating the alignment of polar domains.

  4. Light-control of the ultrafast demagnetization pathway in an antiferromagnetic insulator

    E-Print Network [OSTI]

    Sala, Vera G; Miller, Timothy A; Viola, Daniele; Luppi, Elenora; Véniard, Valérie; Cerullo, Giulio; Wall, Simon

    2015-01-01

    Ultrafast demagnetization is a complex process involving strong coupling between electronic, spin, and structural degrees of freedom which is dependent on the type of magnetic order and band structure. Controlling these interactions is key for developing magnetic devices that can fully exploit femto-magnetism. Here we show that energy and polarization tunable femtosecond light pulses can be used to control the demagnetization pathway in the antiferromagnetic insulator Cr2O3. We visualize how the demagnetization dynamics depends on the pump photon energy using transient second harmonic spectroscopy. This enables us to monitor changes to the magnetic and crystalline symmetry, revealing the key role played by phonons in the demagnetization process. The phonon symmetry can be selected through the colour and polarization of the pump pulse, providing control over the demagnetization process, which could lead to faster and more efficient control of magnetic order.

  5. Ultrafast carrier dynamics in the large-magnetoresistance material WTe2

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dai, Y. M.; Bowlan, J.; Li, H.; Miao, H.; Wu, S. F.; Kong, W. D.; Shi, Y. G.; Trugman, S. A.; Zhu, J. -X.; Ding, H.; et al

    2015-10-07

    In this study, ultrafast optical pump-probe spectroscopy is used to track carrier dynamics in the large-magnetoresistance material WTe2. Our experiments reveal a fast relaxation process occurring on a subpicosecond time scale that is caused by electron-phonon thermalization, allowing us to extract the electron-phonon coupling constant. An additional slower relaxation process, occurring on a time scale of ~5–15 ps, is attributed to phonon-assisted electron-hole recombination. As the temperature decreases from 300 K, the time scale governing this process increases due to the reduction of the phonon population. However, below ~50 K, an unusual decrease of the recombination time sets in, mostmore »likely due to a change in the electronic structure that has been linked to the large magnetoresistance observed in this material.« less

  6. Broadly, independent-tunable, dual-wavelength mid-infrared ultrafast optical parametric oscillator

    E-Print Network [OSTI]

    Jin, Yuwei; Harren, Frans J M; Mandon, Julien

    2015-01-01

    We demonstrate a two-crystal mid-infrared dual-wavelength optical parametric oscillator, synchronously pumped by a high power femtosecond Yb:fiber laser. The singly-resonant ring cavity, containing two periodically poled lithium niobate crystals, is capable of generating two synchronized idler wavelengths, independently tunable over 30 THz in the 2.9 - 4.2 {\\mu}m wavelength region, due to the cascaded quadratic nonlinear effect. The independent tunability of the two idlers makes the optical parametric oscillator a promising source for ultrafast pulse generation towards the THz wavelength region, based on different frequency generation. In addition, the observed frequency doubled idler within the crystal indicates the possibility to realize a broadband optical self-phase locking between pump, signal, idler and higher order generated parametric lights.

  7. 2012 ATOMIC AND MOLECULAR INTERACTIONS GORDON RESEARCH CONFERENCE AND GORDON RESEARCH SEMINAR, JULY 15-20, 2012

    SciTech Connect (OSTI)

    Zwier, Timothy

    2012-07-20

    At the 2012 Atomic and Molecular Interactions Gordon Conference, there will be talks in several broadly defined and partially overlapping areas: ? Intramolecular and single-collision reaction dynamics; ? Photophysics and photochemistry of excited states; ? Clusters, aerosols and solvation; ? Interactions at interfaces; ? Conformations and folding of large molecules; ? Interactions under extreme conditions of temperature and pressure. The theme of the Gordon Research Seminar on Atomic & Molecular Interactions, in keeping with the tradition of the Atomic and Molecular Interactions Gordon Research Conference, is far-reaching and involves fundamental research in the gas and condensed phases along with application of these ideas to practical chemical fields. The oral presentations, which will contain a combination of both experiment and theory, will focus on four broad categories: ? Ultrafast Phenomena; ? Excited States, Photoelectrons, and Photoions; ? Chemical Reaction Dynamics; ? Biomolecules and Clusters.

  8. @Why Physics Comprehensive Physics Major.

    E-Print Network [OSTI]

    Yoo, S. J. Ben

    @Why Physics Comprehensive Physics Major. From the basic laws of physics to the resulting emergent behavior, physics studies what the universe is made of and how it works. As a Physics major that surrounds us, to the structure and evolution of the entire universe. We offer three degrees in Physics

  9. Frequency modulated few-cycle optical pulse trains induced controllable ultrafast coherent population oscillations in three-level atomic systems

    E-Print Network [OSTI]

    Parvendra Kumar; Amarendra K. Sarma

    2012-11-16

    We report a study on the ultrafast coherent population oscillations (UCPO) in two level atoms induced by the frequency modulated few-cycle optical pulse train. The phenomenon of UCPO is investigated by numerically solving the optical Bloch equations beyond the rotating wave approximation. We demonstrate that the quantum state of the atoms and the frequency of UCPO may be controlled by controlling the number of pulses in the pulse trains and the pulse repetition time respectively. Moreover, the robustness of the population inversion against the variation of the laser pulse parameters is also investigated. The proposed scheme may be useful for the creation of atoms in selected quantum state for desired time duration and may have potential applications in ultrafast optical switching.

  10. Frequency modulated few-cycle optical pulse trains induced controllable ultrafast coherent population oscillations in three-level atomic systems

    E-Print Network [OSTI]

    Kumar, Parvendra

    2012-01-01

    We report a study on the ultrafast coherent population oscillations (UCPO) in sodium atoms induced by the frequency modulated few-cycle optical pulse trains. The phenomenon of UCPO is investigated by numerically solving the appropriate density matrix equations beyond the rotating wave approximation. We demonstrate that the quantum state of the atoms and the frequency of UCPO may be controlled by controlling the number of pulses in the pulse trains and the pulse repetition time respectively. Moreover, the robustness of population transfer against the variation of laser pulse parameters is also investigated. The proposed scheme may be useful for the creation of atomic beam in selected quantum state for desired time duration and may have potential applications in ultrafast optical switching.

  11. Undergraduate Programs BIOCHEMISTRY & MOLECULAR

    E-Print Network [OSTI]

    Dellaire, Graham

    Undergraduate Programs in BIOCHEMISTRY & MOLECULAR BIOLOGY Dalhousie University 5850 College Street.............................................................................................................................. 3 1. Biochemistry Degree Programs .............................................................................................................. 4 Minor in Biochemistry & Molecular Biology

  12. Undergraduate Programs BIOCHEMISTRY & MOLECULAR

    E-Print Network [OSTI]

    Dellaire, Graham

    Undergraduate Programs in BIOCHEMISTRY & MOLECULAR BIOLOGY Dalhousie University 9B1 - 5850 College........................................................................................................................................................ 3 1. Biochemistry Degree Programs ............................................................................................................................. 5 Minor in Biochemistry & Molecular Biology

  13. Undergraduate Programs BIOCHEMISTRY & MOLECULAR

    E-Print Network [OSTI]

    Dellaire, Graham

    Undergraduate Programs in BIOCHEMISTRY & MOLECULAR BIOLOGY Dalhousie University 5850 College Street ............................................................................................................................. 3 1. Biochemistry Degree Programs .............................................................................................................. 4 Minor in Biochemistry & Molecular Biology

  14. Syllabus: CHM 5901 The Molecular, Physical, and Artistic Bases of Color This is a half course, which will be offered in the second half of the semester: Feb. 25 to April

    E-Print Network [OSTI]

    of the molecular basis of color. Fundamentals of light; the interaction of radiation with matter; structures, from an artist's perspective, he understood subtleties of the interaction of visible light with matter and refraction; light interaction with bulk matter; measuring light intensity March 4 de Cruz: Historical survey

  15. DEPARTMENT OF PHYSICS Physics 42200

    E-Print Network [OSTI]

    Brinkmann, Peter

    DEPARTMENT OF PHYSICS Syllabus Physics 42200 Biophysics Designation: Undergraduate Catalog and membranes. In depth study of the physical basis of selected systems including vision, nerve transmission. Prerequisites: Prereq.: 1 yr. of Math, 1 yr. of Physics (elective for Physics Majors and Biomedical Engineering

  16. DEPARTMENT OF PHYSICS Physics 32300

    E-Print Network [OSTI]

    Brinkmann, Peter

    DEPARTMENT OF PHYSICS Syllabus Physics 32300 Quantum Mechanics for Engineers Designation: required for Physics majors in the Applied Physics Option Undergraduate Catalog description: Basic experiments, wave: Physics 20700 and 20800, Math 39100 and Math 39200 Textbook and other suggested material: Scherrer

  17. Subatomic Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    P-25 Subatomic Physics We play a major role in large-scale scientific collaborations around the world, performing nuclear physics experiments that advance the understanding of the...

  18. GRADUATE BOOKLET Physics / Applied Physics

    E-Print Network [OSTI]

    Rock, Chris

    GRADUATE BOOKLET Physics / Applied Physics This booklet contains rules, guidelines and general information about graduate studies in the Physics Department at Texas Tech University. It does not replace documents. Contents I. General Comments: Admission, general policies, deadlines, etc II. Minimum

  19. PHYSICAL REVIEW A 82, 013820 (2010) Ultrafast double-quantum-coherence spectroscopy of excitons with entangled photons

    E-Print Network [OSTI]

    Mukamel, Shaul

    2010-01-01

    with entangled photons Marten Richter* and Shaul Mukamel Department of Chemistry, University of California Irvine-wave-mixing signal of excitons generated at k4 = k1 + k2 - k3 by two pulsed entangled photon pairs (k1, k2) and (k3, k4), where all four modes are chronologically ordered. Entangled photons offer an unusual

  20. Quantum physics meets biology

    E-Print Network [OSTI]

    Markus Arndt; Thomas Juffmann; Vlatko Vedral

    2009-11-01

    Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the last decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world view of quantum coherences, entanglement and other non-classical effects, has been heading towards systems of increasing complexity. The present perspective article shall serve as a pedestrian guide to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future quantum biology, its current status, recent experimental progress and also the restrictions that nature imposes on bold extrapolations of quantum theory to macroscopic phenomena.

  1. Physics PhD Mentors at CCNY, 2014 (Please also see faculty and staff profiles on the Physics website)

    E-Print Network [OSTI]

    Sun, Yi

    Physics PhD Mentors at CCNY, 2014 (Please also see faculty and staff profiles on the Physics molecular biological physics; electron and proton transfer reactions; solar energy Koder, Ronald koder@sci.ccny.c uny.edu http://web.sci.ccny.cuny.edu/~koder/koder.ht ml experimental biological physics; de novo #12

  2. THEORETICAL PHYSICS Faculty of Physics

    E-Print Network [OSTI]

    Pachucki, Krzysztof

    of Field Theory and Statistical Physics RG Division of General Relativity and Gravitation MP DivisionINSTITUTE OF THEORETICAL PHYSICS Faculty of Physics Warsaw University 1998-1999 Warsaw 2000 #12;INSTITUTE OF THEORETICAL PHYSICS Address: Hoza 69, PL-00 681 Warsaw, Poland Phone: (+48 22) 628 33 96 Fax

  3. Velocity measurements in the near field of a diesel fuel injector by ultrafast imagery

    E-Print Network [OSTI]

    Sedarsky, David; Blaisot, Jean-Bernard; Rozé, Claude

    2013-01-01

    This paper examines the velocity profile of fuel issuing from a high-pressure single-orifice diesel injector. Velocities of liquid structures were determined from time-resolved ultrafast shadow images, formed by an amplified two-pulse laser source coupled to a double-frame camera. A statistical analysis of the data over many injection events was undertaken to map velocities related to spray formation near the nozzle outlet as a function of time after start of injection. These results reveal a strong asymmetry in the liquid profile of the test injector, with distinct fast and slow regions on opposite sides of the orifice. Differences of ~100 m/s can be observed between the 'fast' and 'slow' sides of the jet, resulting in different atomization conditions across the spray. On average, droplets are dispersed at a greater distance from the nozzle on the 'fast' side of the flow, and distinct macrostructure can be observed under the asymmetric velocity conditions. The changes in structural velocity and atomization b...

  4. On the presence of ultra-fast outflows in the WAX sample of Seyfert galaxies

    E-Print Network [OSTI]

    Tombesi, Francesco

    2014-01-01

    The study of winds in active galactic nuclei (AGN) is of utmost importance as they may provide the long sought-after link between the central black hole and the host galaxy, establishing the AGN feedback. Recently, Laha et al. (2014) reported the X-ray analysis of a sample of 26 Seyferts observed with XMM-Newton, which are part of the so-called warm absorbers in X-rays (WAX) sample. They claim the non-detection of Fe K absorbers indicative of ultra-fast outflows (UFOs) in four observations previously analyzed by Tombesi et al. (2010). They mainly impute the Tombesi et al. detections to an improper modeling of the underlying continuum in the E=4-10 keV band. We therefore re-address here the robustness of these detections and we find that the main reason for the claimed non-detections is likely due to their use of single events only spectra, which reduces the total counts by 40%. Performing a re-analysis of the data in the whole E=0.3-10 keV energy band using their models and spectra including also double event...

  5. Surface modified CFx cathode material for ultrafast discharge and high energy density

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dai, Yang [Shanghai Inst. of Space Power Sources, Shanghai (China); Zhu, Yimei [Brookhaven National Lab. (BNL), Upton, NY (United States); Cai, Sendan [Shanghai Inst. of Space Power Sources, Shanghai (China); Wu, Lijun [Brookhaven National Lab. (BNL), Upton, NY (United States); Yang, Weijing [Shanghai Inst. of Space Power Sources, Shanghai (China); Xie, Jingying [Shanghai Inst. of Space Power Sources, Shanghai (China); Shanghai Engineering Center for Power and Energy Storage Systems, Shanghai (China); Wen, Wen [BL14B1 Shanghai Synchrotron Radiation Facility, Shanghai (China); Zheng, Jin-Cheng [Xiamen Univ., Xiamen (China); Zheng, Yi [Shanghai Inst. of Space Power Sources, Shanghai (China)

    2014-01-01

    Li/CFx primary possesses the highest energy density of 2180 W h kg?¹ among all primary lithium batteries. However, a key limitation for the utility of this type of battery is in its poor rate capability because the cathode material, CFx, is an intrinsically poor electronic conductor. Here, we report on our development of a controlled process of surface de-fluorination under mild hydrothermal conditions to modify the highly fluorinated CFx. The modified CFx, consisting of an in situ generated shell component of F-graphene layers, possesses good electronic conductivity and removes the transporting barrier for lithium ions, yielding a high-capacity performance and an excellent rate-capability. Indeed, a capacity of 500 mA h g?¹ and a maximum power density of 44 800 W kg?¹ can be realized at the ultrafast rate of 30 C (24 A g?¹), which is over one order of magnitude higher than that of the state-of-the-art primary lithium-ion batteries.

  6. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Miaja-Avila, L.; O'Neil, G. C.; Uhlig, J.; Cromer, C. L.; Dowell, M. L.; Jimenez, R.; Hoover, A. S.; Silverman, K. L.; Ullom, J. N.

    2015-03-02

    We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 ?m FWHM x-ray spot size, containing ~106 photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >107 laser pulses, we also presentmore »data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.« less

  7. Surface modified CFx cathode material for ultrafast discharge and high energy density

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Dai, Yang; Zhu, Yimei; Cai, Sendan; Wu, Lijun; Yang, Weijing; Xie, Jingying; Wen, Wen; Zheng, Jin-Cheng; Zheng, Yi

    2014-11-10

    Li/CFx primary possesses the highest energy density of 2180 W h kg?¹ among all primary lithium batteries. However, a key limitation for the utility of this type of battery is in its poor rate capability because the cathode material, CFx, is an intrinsically poor electronic conductor. Here, we report on our development of a controlled process of surface de-fluorination under mild hydrothermal conditions to modify the highly fluorinated CFx. The modified CFx, consisting of an in situ generated shell component of F-graphene layers, possesses good electronic conductivity and removes the transporting barrier for lithium ions, yielding a high-capacity performance andmore »an excellent rate-capability. Indeed, a capacity of 500 mA h g?¹ and a maximum power density of 44 800 W kg?¹ can be realized at the ultrafast rate of 30 C (24 A g?¹), which is over one order of magnitude higher than that of the state-of-the-art primary lithium-ion batteries.« less

  8. Ultrafast nanolaser device for detecting cancer in a single live cell.

    SciTech Connect (OSTI)

    Gourley, Paul Lee; McDonald, Anthony Eugene

    2007-11-01

    Emerging BioMicroNanotechnologies have the potential to provide accurate, realtime, high throughput screening of live tumor cells without invasive chemical reagents when coupled with ultrafast laser methods. These optically based methods are critical to advancing early detection, diagnosis, and treatment of disease. The first year goals of this project are to develop a laser-based imaging system integrated with an in- vitro, live-cell, micro-culture to study mammalian cells under controlled conditions. In the second year, the system will be used to elucidate the morphology and distribution of mitochondria in the normal cell respiration state and in the disease state for normal and disease states of the cell. In this work we designed and built an in-vitro, live-cell culture microsystem to study mammalian cells under controlled conditions of pH, temp, CO2, Ox, humidity, on engineered material surfaces. We demonstrated viability of cell culture in the microsystem by showing that cells retain healthy growth rates, exhibit normal morphology, and grow to confluence without blebbing or other adverse influences of the material surfaces. We also demonstrated the feasibility of integrating the culture microsystem with laser-imaging and performed nanolaser flow spectrocytometry to carry out analysis of the cells isolated mitochondria.

  9. Ripening of one-dimensional molecular nanostructures on

    E-Print Network [OSTI]

    Steinhoff, Heinz-Jürgen

    self-assembly became of great importance to enable the tailoring of such molecular structures (forRipening of one-dimensional molecular nanostructures on insulating surfaces Master Thesis Tobias, because of the well-known physical limits in silicon technology. To overcome obsta- cles of silicon-based

  10. Molecular CP-violating magnetic moment Andrei Derevianko1

    E-Print Network [OSTI]

    Titov, Anatoly

    Molecular CP-violating magnetic moment Andrei Derevianko1 and M. G. Kozlov2 1 Department of Physics Received 26 April 2005; published 6 October 2005 A concept of CP-violating T,P-odd permanent molecular magnetic moments CP is introduced. We relate the moments to the electric dipole moment of electron e

  11. Control of molecular dynamics with zero-area fields: Application to molecular orientation and photofragmentation

    E-Print Network [OSTI]

    D. Sugny; Stéphane Vranckx; Mamadou Ndong; Nathalie Vaeck; Osman Atabek; Michèle Desouter-Lecomte

    2014-12-15

    The constraint of time-integrated zero-area on the laser field is a fundamental, both theoretical and experimental requirement in the control of molecular dynamics. By using techniques of local and optimal control theory, we show how to enforce this constraint on two benchmark control problems, namely molecular orientation and photofragmentation. The origin and the physical implications on the dynamics of this zero-area control field are discussed.

  12. Role of nuclear dynamics in the Asymmetric molecular-frame photoelectron angular distributions for C 1s photoejection from CO{sub 2}

    SciTech Connect (OSTI)

    Miyabe, Shungo; Haxton, Dan; Rescigno, Tom; McCurdy, Bill

    2010-11-30

    We report the results of semiclassical calculations of the asymmetric molecular-frame photoelectron angular distributions for C 1s ionization of CO{sub 2} measured with respect to the CO{sup +} and O{sup +} ions produced by subsequent Auger decay, and show how the decay event can be used to probe ultrafast molecular dynamics of the transient cation. The fixed-nuclei photoionization amplitudes were constructed using variationally obtained electron-molecular ion scattering wave functions. The amplitudes are then used in a semiclassical manner to investigate their dependence on the nuclear dynamics of the cation. The method introduced here can be used to study other core-level ionization events.

  13. Uranium molecular laser isotope separation

    SciTech Connect (OSTI)

    Jensen, R.J.; Sullivan, A.

    1982-01-01

    The Molecular Laser Isotope Separation program is moving into the engineering phase, and it is possible to determine in some detail the plant cost terms involved in the process economics. A brief description of the MLIS process physics is given as a motivation to the engineering and economics discussion. Much of the plant cost arises from lasers and the overall optical system. In the paper, the authors discuss lasers as operating units and systems, along with temporal multiplexing and Raman shifting. Estimates of plant laser costs are given.

  14. Interfacial Engineering of Molecular Photovoltaics

    E-Print Network [OSTI]

    Shelton, Steven Wade

    2014-01-01

    Engineering of Molecular Photovoltaics by Steven WadeEngineering of Molecular Photovoltaics Copyright © 2014 byEngineering of Molecular Photovoltaics by Steven Wade

  15. Quantum logic with molecular ions

    E-Print Network [OSTI]

    Fabian Wolf; Yong Wan; Jan C. Heip; Florian Gebert; Chunyan Shi; Piet O. Schmidt

    2015-07-27

    Laser spectroscopy of cold and trapped molecular ions is a powerful tool for fundamental physics, including the determination of fundamental constants, the laboratory test for their possible variation, and the search for a possible electric dipole moment of the electron. Optical clocks based on molecular ions sensitive to some of these effects are expected to achieve uncertainties approaching the $10^{-18}$ level. While the complexity of molecular structure facilitates these applications, the absence of cycling transitions poses a challenge for direct laser cooling, quantum state control, and detection. Previously employed state detection techniques based on photo-dissociation or chemical reactions are destructive and therefore inefficient. Here we experimentally demonstrate non-destructive state detection of a single trapped molecular ion through its strong Coulomb coupling to a well-controlled co-trapped atomic ion. An algorithm based on a state-dependent optical dipole force(ODF) changes the internal state of the atom conditioned on the internal state of the molecule. We show that individual states in the molecule can be distinguished by their coupling strength to the ODF and observe black-body radiation-induced quantum jumps between rotational states. Using the detuning dependence of the state detection signal, we implement a variant of quantum logic spectroscopy and improve upon a previous measurement of the $\\mathrm{X}^1\\Sigma^+(J=1)\\rightarrow\\mathrm{A}^1\\Sigma^+(J=0)$ transition in MgH, finding a frequency of 1067.74752(53)THz. We estimate that non-destructive state detection with near 100% efficiency could take less than 10 ms. The technique we demonstrate is applicable to a wide range of molecular ions, enabling further applications in state-controlled quantum chemistry and spectroscopic investigations of molecules serving as probes for interstellar clouds.

  16. Teaching symmetry in the introductory physics curriculum

    SciTech Connect (OSTI)

    Hill, C. T.; Lederman, L. M.

    2000-01-01

    Modern physics is largely defined by fundamental symmetry principles and Noether's Theorem. Yet these are not taught, or rarely mentioned, to beginning students, thus missing an opportunity to reveal that the subject of physics is as lively and contemporary as molecular biology, and as beautiful as the arts. We prescribe a symmetry module to insert into the curriculum, of a week's length.

  17. Ultrafast dark-field surface inspection with hybrid-dispersion laser scanning

    SciTech Connect (OSTI)

    Yazaki, Akio; Kim, Chanju; Chan, Jacky; Mahjoubfar, Ata; Goda, Keisuke; Watanabe, Masahiro; Jalali, Bahram

    2014-06-23

    High-speed surface inspection plays an important role in industrial manufacturing, safety monitoring, and quality control. It is desirable to go beyond the speed limitation of current technologies for reducing manufacturing costs and opening a new window onto a class of applications that require high-throughput sensing. Here, we report a high-speed dark-field surface inspector for detection of micrometer-sized surface defects that can travel at a record high speed as high as a few kilometers per second. This method is based on a modified time-stretch microscope that illuminates temporally and spatially dispersed laser pulses on the surface of a fast-moving object and detects scattered light from defects on the surface with a sensitive photodetector in a dark-field configuration. The inspector's ability to perform ultrafast dark-field surface inspection enables real-time identification of difficult-to-detect features on weakly reflecting surfaces and hence renders the method much more practical than in the previously demonstrated bright-field configuration. Consequently, our inspector provides nearly 1000 times higher scanning speed than conventional inspectors. To show our method's broad utility, we demonstrate real-time inspection of the surface of various objects (a non-reflective black film, transparent flexible film, and reflective hard disk) for detection of 10??m or smaller defects on a moving target at 20?m/s within a scan width of 25?mm at a scan rate of 90.9?MHz. Our method holds promise for improving the cost and performance of organic light-emitting diode displays for next-generation smart phones, lithium-ion batteries for green electronics, and high-efficiency solar cells.

  18. Ultrafast pump-probe force microscopy with nanoscale resolution Junghoon Jahng, Jordan Brocious, Dmitry A. Fishman, Steven Yampolsky, Derek Nowak, Fei Huang, Vartkess

    E-Print Network [OSTI]

    Potma, Eric Olaf

    Ultrafast pump-probe force microscopy with nanoscale resolution Junghoon Jahng, Jordan Brocious and reconfigurable setup for all-terahertz time-resolved pump-probe spectroscopy Rev. Sci. Instrum. 83, 053107 (2012); 10.1063/1.4717732 Femtosecond time-resolved optical pump-probe spectroscopy at kilohertz

  19. Use of Ultrafast Dispersed Pump-Dump-Probe and Pump-Repump-Probe Spectroscopies to Explore the Light-Induced Dynamics of Peridinin in Solution

    E-Print Network [OSTI]

    van Stokkum, Ivo

    Use of Ultrafast Dispersed Pump-Dump-Probe and Pump-Repump-Probe Spectroscopies to Explore Form: NoVember 14, 2005 Optical pump-induced dynamics of the highly asymmetric carotenoid peridinin in methanol was studied by dispersed pump-probe, pump-dump-probe, and pump-repump-probe transient absorption

  20. Ultrafast Electron Diffraction with Spatiotemporal Resolution of Atomic Motion This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Cao, Jianming

    of contents for this issue, or go to the journal homepage for more Home Search Collections Journals About lattice motions in an aluminium thin-film, trigged by ultrafast laser heating, have been observed- ing sub-picosecond pulses containing a few thousands of particles per pulse. Under this low source

  1. Transition from ultrafast laser photo-electron emission to space charge limited current in a 1D gap

    E-Print Network [OSTI]

    Yangjie Liu; L. K. Ang

    2014-08-21

    A one-dimensional (1D) model has been constructed to study the transition of the time-dependent ultrafast laser photo-electron emission from a flat metallic surface to the space charge limited (SCL) current, including the effect of non-equilibrium laser heating on metals at the ultrafast time scale. At a high laser field, it is found that the space charge effect cannot be ignored and the SCL current emission is reached at a lower value predicted by a short pulse SCL current model that assumed a time-independent emission process. The threshold of the laser field to reach the SCL regime is determined over a wide range of operating parameters. The calculated results agree well with particle-in-cell (PIC) simulation. It is found that the space charge effect is more important for materials with lower work function like tungsten (4.4 eV) as compared to gold (5.4 eV). However for a flat surface, both materials will reach the space charge limited regime at the sufficiently high laser field such as $>$ 5 GV/m with a laser pulse length of tens to one hundred femtoseconds.

  2. Physics of Grain Alignment

    E-Print Network [OSTI]

    Lazarian A

    2000-03-22

    Aligned grains provide one of the easiest ways to study magnetic fields in diffuse gas and molecular clouds. How reliable our conclusions about the inferred magnetic field depends critically on our understanding of the physics of grain alignment. Although grain alignment is a problem of half a century standing recent progress achieved in the field makes us believe that we are approaching the solution of this mystery. I review basic physical processes involved in grain alignment and show why mechanisms that were favored for decades do not look so promising right now. I also discuss why the radiative torque mechanism ignored for more than 20 years looks right now the most powerful means of grain alignment.

  3. Physics Division annual report, April 1, 1993--March 31, 1994

    SciTech Connect (OSTI)

    Thayer, K.J. [ed.; Henning, W.F.

    1994-08-01

    This is the Argonne National Laboratory Physics Division Annual Report for the period April 1, 1993 to March 31, 1994. It summarizes work done in a number of different fields, both on site, and at other facilities. Chapters describe heavy ion nuclear physics research, operation and development of the ATLAS accelerator, medium-energy nuclear physics research, theoretical physics, and atomic and molecular physics research.

  4. Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    state. Formed at high temperatures, plasmas consist of freely moving ions and free electrons. They are often called the "fourth state of matter" because their unique physical...

  5. Theoretical Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    HEP Theoretical Physics Understanding discoveries at the Energy, Intensity, and Cosmic Frontiers Get Expertise Rajan Gupta (505) 667-7664 Email Bruce Carlsten (505) 667-5657 Email...

  6. Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    4 Plasma Physics By leveraging plasma under extreme conditions, we concentrate on solving critical scientific challenges such as detecting smuggled nuclear materials, advancing...

  7. PANKAJ MEHTA 2010-Assistant Professor, Dept. of Physics, Boston University

    E-Print Network [OSTI]

    Mehta, Pankaj

    PANKAJ MEHTA 2010- Assistant Professor, Dept. of Physics, Boston University 2011- Member, Graduate Commonwealth Ave Boston, MA 02215 Phone: +1 617 358 6303 email: pankajm@bu.edu http://physics.bu.edu/~pankajm Education 2006-2010 Postdoctoral Scholar, Molecular Biology and Physics, Princeton University (Mentor: Ned

  8. Biochemistry and Molecular Biophysics

    E-Print Network [OSTI]

    Sharp, Kim

    cell with a monopolar spindle shows a gradient of Aurora B phosphorylation spreading outward from; molecular immunology; protein structure, dynamics and folding; enzymology; regulation of metabolism; RNA

  9. Molecular Phylogenetics (Hannes Luz)

    E-Print Network [OSTI]

    Spang, Rainer

    Molecular Phylogenetics (Hannes Luz) Contents: · Phylogenetic Trees, basic notions · A character Berlin, 2007) · Martin Vingron, Hannes Luz, Jens Stoye, Lecture notes on 'Al- gorithms for Phylogenetic

  10. Physics & Astronomy Degree options

    E-Print Network [OSTI]

    Brierley, Andrew

    148 Physics & Astronomy Degree options BSc (Single Honours Degrees) Astrophysics Physics MPhys (Single Honours Degrees) Astrophysics Physics Theoretical Physics BSc (Joint Honours Degrees) Physics) Theoretical Physics and Mathematics MSci (Joint Honours Degree) Physics and Chemistry Entrance Requirements

  11. Synthesis, Characterization, and Ultrafast Dynamics of Metal, Metal Oxide, and Semiconductor Nanomaterials

    E-Print Network [OSTI]

    Wheeler, Damon Andreas

    2013-01-01

    study using atomic layer deposition," Journal Of PhysicalArrays Formed by Atomic Layer Deposition. 2011, 115, 9498-Cells Prepared by Atomic Layer Deposition. 2011, 27, 461-

  12. DEPARTMENT OF PHYSICS Physics 35400

    E-Print Network [OSTI]

    Lombardi, John R.

    , electromagnetic waves in vacuum and in matter, guided waves ­ transmission lines and waveguides, electromagnetic-varying sources 7. calculate the electromagnetic radiation fields and power emitted for electric dipole sources 8DEPARTMENT OF PHYSICS Syllabus Physics 35400 Electricity and Magnetism II Designation

  13. Homogeneous Non-Equilibrium Molecular Dynamics Methods for Calculating the Heat Transport Coefficient of Solids and Mixtures

    E-Print Network [OSTI]

    Mandadapu, Kranthi Kiran

    2011-01-01

    of flexible molecules - Butane. Molecular Physics, 81(6):in polyatomic fluids: n-Butane as an illustration. Chemicalfor two models of liquid Butane. Chemical Physics, 198(1-2):

  14. Physical Scientist

    Broader source: Energy.gov [DOE]

    The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, providing more than 40 percent of total funding for this vital area of...

  15. Ultrafast time-resolved spectroscopy of the light-harvesting complex 2 (LH2) from the photosynthetic bacterium Thermochromatium tepidum

    SciTech Connect (OSTI)

    Niedzwiedzki, Dariusz M.; Fuciman, Marcel; Kobayashi, Masayuki; Frank, Harry A.; Blankenship, Robert E.

    2011-10-08

    The light-harvesting complex 2 from the thermophilic purple bacterium Thermochromatium tepidum was purified and studied by steady-state absorption and fluorescence, sub-nanosecond-time-resolved fluorescence and femtosecond time-resolved transient absorption spectroscopy. The measurements were performed at room temperature and at 10 K. The combination of both ultrafast and steady-state optical spectroscopy methods at ambient and cryogenic temperatures allowed the detailed study of carotenoid (Car)-to-bacteriochlorophyll (BChl) as well BChl-to-BChl excitation energy transfer in the complex. The studies show that the dominant Cars rhodopin (N = 11) and spirilloxanthin (N = 13) do not play a significant role as supportive energy donors for BChl a. This is related with their photophysical properties regulated by long ?-electron conjugation. On the other hand, such properties favor some of the Cars, particularly spirilloxanthin (N = 13) to play the role of the direct quencher of the excited singlet state of BChl.

  16. High quality single shot ultrafast MeV electron diffraction from a photocathode radio-frequency gun

    SciTech Connect (OSTI)

    Fu, Feichao; Liu, Shengguang; Zhu, Pengfei; Xiang, Dao Zhang, Jie; Cao, Jianming

    2014-08-15

    A compact ultrafast electron diffractometer, consisting of an s-band 1.6 cell photocathode radio-frequency gun, a multi-function changeable sample chamber, and a sensitive relativistic electron detector, was built at Shanghai Jiao Tong University. High-quality single-shot transmission electron diffraction patterns have been recorded by scattering 2.5?MeV electrons off single crystalline gold and polycrystalline aluminum samples. The high quality diffraction pattern indicates an excellent spatial resolution, with the ratio of the diffraction ring radius over the ring rms width beyond 10. The electron pulse width is estimated to be about 300 fs. The high temporal and spatial resolution may open new opportunities in various areas of sciences.

  17. Cost effective nanostructured copper substrates prepared with ultrafast laser pulses for explosives detection using surface enhanced Raman scattering

    SciTech Connect (OSTI)

    Hamad, Syed; Podagatlapalli, G. Krishna; Soma, Venugopal Rao E-mail: soma-venu@yahoo.com; Mohiddon, Md. Ahamad

    2014-06-30

    Ultrafast laser pulses induced surface nanostructures were fabricated on a copper (Cu) target through ablation in acetone, dichloromethane, acetonitrile, and chloroform. Surface morphological information accomplished from the field emission scanning electron microscopic data demonstrated the diversities of ablation mechanism in each case. Fabricated Cu substrates were utilized exultantly to investigate the surface plasmon (localized and propagating) mediated enhancements of different analytes using surface enhance Raman scattering (SERS) studies. Multiple utility of these substrates were efficiently demonstrated by collecting the SERS data of Rhodamine 6G molecule and two different secondary explosive molecules such as 5-amino-3-nitro-l,2,4-triazole and trinitrotoluene on different days which were weeks apart. We achieved significant enhancement factors of >10{sup 5} through an easily adoptable cleaning procedure.

  18. Time-resolved spectroscopy of CI and CII line emissions from an ultrafast laser induced solid graphite plasma

    SciTech Connect (OSTI)

    N, Smijesh, E-mail: smiju5247@gmail.com [Lasers and Nonlinear optics lab, Department of Physics, National Institute of Technology Calicut, Kozhikode - 673 601 India and Raman Research Institute, Sadashivanagar, Bangalore 560080 (India); K, Chandrasekharan, E-mail: csk@nitc.ac.in [Lasers and Nonlinear optics lab, Department of Physics, National Institute of Technology Calicut, Kozhikode - 673 601 (India); Philip, Reji, E-mail: reij@rri.res.in [Raman Research Institute, Sadashivanagar, Bangalore 560080 (India)

    2014-10-15

    We present an experimental characterization of the evolution dynamics of CI and CII lines in an ultrafast laser produced graphite plasma under various ambient conditions. Fast and slow components are observed in the temporal evolution of CI transition at 658.7 nm (3p{sup 1}P - 4d{sup 1}P{sup 0}) and CII transition at 426.7 nm (3d {sup 2}D - 4f {sup 2}F{sup 0}). Fast peak is due to the recombination of fast ions species with electrons, found to have an increase in velocity upon increasing the ambient pressure. Whereas the slow peaks in both cases can be the results of slow ions or slow neutrals in the plume.

  19. Ultrafast single-electron transfer in coupled quantum dots driven by a few-cycle chirped pulse

    SciTech Connect (OSTI)

    Yang, Wen-Xing, E-mail: wenxingyang2@126.com [Department of Physics, Southeast University, Nanjing 210096 (China); Institute of Photonics Technologies, National Tsing-Hua University, Hsinchu 300, Taiwan (China); Chen, Ai-Xi [Department of Applied Physics, School of Basic Science, East China Jiaotong University, Nanchang 330013 (China); Bai, Yanfeng [Department of Physics, Southeast University, Nanjing 210096 (China); Lee, Ray-Kuang [Institute of Photonics Technologies, National Tsing-Hua University, Hsinchu 300, Taiwan (China)

    2014-04-14

    We theoretically study the ultrafast transfer of a single electron between the ground states of a coupled double quantum dot (QD) structure driven by a nonlinear chirped few-cycle laser pulse. A time-dependent Schrödinger equation without the rotating wave approximation is solved numerically. We demonstrate numerically the possibility to have a complete transfer of a single electron by choosing appropriate values of chirped rate parameters and the intensity of the pulse. Even in the presence of the spontaneous emission and dephasing processes of the QD system, high-efficiency coherent transfer of a single electron can be obtained in a wide range of the pulse parameters. Our results illustrate the potential to utilize few-cycle pulses for the excitation in coupled quantum dot systems through the nonlinear chirp parameter control, as well as a guidance in the design of experimental implementation.

  20. Electron-ion relaxation time dependent signal enhancement in ultrafast double-pulse laser-induced breakdown spectroscopy

    SciTech Connect (OSTI)

    Harilal, S. S.; Diwakar, P. K.; Hassanein, A. [Center for Materials Under Extreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)] [Center for Materials Under Extreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

    2013-07-22

    We investigated the emission properties of collinear double-pulse compared to single-pulse ultrafast laser induced breakdown spectroscopy. Our results showed that the significant signal enhancement noticed in the double pulse scheme is strongly correlated to the characteristic electron-ion relaxation time and hence to the inter-pulse delays. Spectroscopic excitation temperature analysis showed that the improvement in signal enhancement is caused by the delayed pulse efficient reheating of the pre-plume. The signal enhancement is also found to be related to the upper excitation energy of the selected lines, i.e., more enhancement noticed for lines originating from higher excitation energy levels, indicating reheating is the major mechanism behind the signal improvement.

  1. Vibronic coupling explains the ultrafast carotenoid-to-bacteriochlorophyll energy transfer in natural and artificial light harvesters

    E-Print Network [OSTI]

    Perlík, Václav; Cranston, Laura J; Cogdell, Richard J; Lincoln, Craig N; Savolainen, Janne; Šanda, František; Man?al, Tomáš; Hauer, Jürgen

    2015-01-01

    The initial energy transfer in photosynthesis occurs between the light-harvesting pigments and on ultrafast timescales. We analyze the carotenoid to bacteriochlorophyll energy transfer in LH2 Marichromatium purpuratum as well as in an artificial light-harvesting dyad system by using transient grating and two-dimensional electronic spectroscopy with 10 fs time resolution. We find that F\\"orster-type models reproduce the experimentally observed 60 fs transfer times, but overestimate coupling constants, which leads to a disagreement with both linear absorption and electronic 2D-spectra. We show that a vibronic model, which treats carotenoid vibrations on both electronic ground and excited state as part of the system's Hamiltonian, reproduces all measured quantities. Importantly, the vibronic model presented here can explain the fast energy transfer rates with only moderate coupling constants, which are in agreement with structure based calculations. Counterintuitively, the vibrational levels on the carotenoid el...

  2. Water-Stable, Hydroxamate Anchors for Functionalization of TiO{sub 2} Surfaces with Ultrafast Interfacial Electron Transfer

    SciTech Connect (OSTI)

    McNamara, W. R.; Milot, R. L.; Song, H.; Snoeberger III, R. C.; Batista, Victor S.; Schmuttenmaer, C. A.; Brudvig, Gary W.; Crabtree, Robert H.

    2010-01-01

    A novel class of derivatized hydroxamic acid linkages for robust sensitization of TiO{sub 2} nanoparticles (NPs) under various aqueous conditions is described. The stability of linkages bound to metal oxides under various conditions is important in developing photocatalytic cells which incorporate transition metal complexes for solar energy conversion. In order to compare the standard carboxylate anchor to hydroxamates, two organic dyes differing only in anchoring groups were synthesized and attached to TiO{sub 2} NPs. At acidic, basic, and close to neutral pH, hydroxamic acid linkages resist detachment compared to the labile carboxylic acids. THz spectroscopy was used to compare ultrafast interfacial electron transfer (IET) into the conduction band of TiO{sub 2} for both linkages and found similar IET characteristics. Observable electron injection and stronger binding suggest that hydroxamates are a suitable class of anchors for designing water stable molecules for functionalizing TiO{sub 2}.

  3. A physical sciences network characterization of non-tumorigenic and metastatic cells

    E-Print Network [OSTI]

    Jacks, Tyler E.

    To investigate the transition from non-cancerous to metastatic from a physical sciences perspective, the Physical Sciences–Oncology Centers (PS-OC) Network performed molecular and biophysical comparative studies of the ...

  4. DepartmentofPhysics David Coker

    E-Print Network [OSTI]

    Gürel, Levent

    University, Massachusetts, USA Energy transfer and charge separation dynamics in natural and artificial nano in laboratories around the world for applications in arti cial photosynthesis, and the nano technologies ultrafast nonlinear spectroscopy studies and model theoretical calculations [1-4] that suggest

  5. System and method for ultrafast optical signal detecting via a synchronously coupled anamorphic light pulse encoded laterally

    DOE Patents [OSTI]

    Heebner, John E. (Livermore, CA)

    2010-08-03

    In one general embodiment, a method for ultrafast optical signal detecting is provided. In operation, a first optical input signal is propagated through a first wave guiding layer of a waveguide. Additionally, a second optical input signal is propagated through a second wave guiding layer of the waveguide. Furthermore, an optical control signal is applied to a top of the waveguide, the optical control signal being oriented diagonally relative to the top of the waveguide such that the application is used to influence at least a portion of the first optical input signal propagating through the first wave guiding layer of the waveguide. In addition, the first and the second optical input signals output from the waveguide are combined. Further, the combined optical signals output from the waveguide are detected. In another general embodiment, a system for ultrafast optical signal recording is provided comprising a waveguide including a plurality of wave guiding layers, an optical control source positioned to propagate an optical control signal towards the waveguide in a diagonal orientation relative to a top of the waveguide, at least one optical input source positioned to input an optical input signal into at least a first and a second wave guiding layer of the waveguide, and a detector for detecting at least one interference pattern output from the waveguide, where at least one of the interference patterns results from a combination of the optical input signals input into the first and the second wave guiding layer. Furthermore, propagation of the optical control signal is used to influence at least a portion of the optical input signal propagating through the first wave guiding layer of the waveguide.

  6. On Factorization of Molecular Wavefunctions

    E-Print Network [OSTI]

    Thierry Jecko; Brian T. Sutcliffe; R. Guy Woolley

    2015-07-18

    Recently there has been a renewed interest in the chemical physics literature of factorization of the position representation eigenfunctions \\{$\\Phi$\\} of the molecular Schr\\"odinger equation as originally proposed by Hunter in the 1970s. The idea is to represent $\\Phi$ in the form $\\varphi\\chi$ where $\\chi$ is \\textit{purely} a function of the nuclear coordinates, while $\\varphi$ must depend on both electron and nuclear position variables in the problem. This is a generalization of the approximate factorization originally proposed by Born and Oppenheimer, the hope being that an `exact' representation of $\\Phi$ can be achieved in this form with $\\varphi$ and $\\chi$ interpretable as `electronic' and `nuclear' wavefunctions respectively. We offer a mathematical analysis of these proposals that identifies ambiguities stemming mainly from the singularities in the Coulomb potential energy.

  7. On Factorization of Molecular Wavefunctions

    E-Print Network [OSTI]

    Thierry Jecko; Brian T. Sutcliffe; R. Guy Woolley

    2015-09-05

    Recently there has been a renewed interest in the chemical physics literature of factorization of the position representation eigenfunctions \\{$\\Phi$\\} of the molecular Schr\\"odinger equation as originally proposed by Hunter in the 1970s. The idea is to represent $\\Phi$ in the form $\\varphi\\chi$ where $\\chi$ is \\textit{purely} a function of the nuclear coordinates, while $\\varphi$ must depend on both electron and nuclear position variables in the problem. This is a generalization of the approximate factorization originally proposed by Born and Oppenheimer, the hope being that an `exact' representation of $\\Phi$ can be achieved in this form with $\\varphi$ and $\\chi$ interpretable as `electronic' and `nuclear' wavefunctions respectively. We offer a mathematical analysis of these proposals that identifies ambiguities stemming mainly from the singularities in the Coulomb potential energy.

  8. On Factorization of Molecular Wavefunctions

    E-Print Network [OSTI]

    Thierry Jecko; Brian T. Sutcliffe; R. Guy Woolley

    2015-10-13

    Recently there has been a renewed interest in the chemical physics literature of factorization of the position representation eigenfunctions \\{$\\Phi$\\} of the molecular Schr\\"odinger equation as originally proposed by Hunter in the 1970s. The idea is to represent $\\Phi$ in the form $\\varphi\\chi$ where $\\chi$ is \\textit{purely} a function of the nuclear coordinates, while $\\varphi$ must depend on both electron and nuclear position variables in the problem. This is a generalization of the approximate factorization originally proposed by Born and Oppenheimer, the hope being that an `exact' representation of $\\Phi$ can be achieved in this form with $\\varphi$ and $\\chi$ interpretable as `electronic' and `nuclear' wavefunctions respectively. We offer a mathematical analysis of these proposals that identifies ambiguities stemming mainly from the singularities in the Coulomb potential energy.

  9. Physics Based on Physical Monism

    E-Print Network [OSTI]

    Seong-Dong Kim

    2006-03-22

    Based on a physical monism, which holds that the matter and space are classified by not a difference of their kind but a difference of magnitude of their density, I derive the most fundamental equation of motion, which is capable of providing a deeper physical understanding than the known physics. For example, this equation answers to the substantive reason of movement, and Newton's second law, which has been regarded as the definition of force, is derived in a substantive level from this equation. Further, the relativistic energy-mass formula is generalized to include the potential energy term, and the Lorentz force and Maxwell equations are newly derived.

  10. The 2011 Dynamics of Molecular Collisions Conference

    SciTech Connect (OSTI)

    Nesbitt, David J.

    2011-07-11

    The Dynamics of Molecular Collisions Conference focuses on all aspects of molecular collisions--experimental & theoretical studies of elastic, inelastic, & reactive encounters involving atoms, molecules, ions, clusters, & surfaces--as well as half collisions--photodissociation, photo-induced reaction, & photodesorption. The scientific program for the meeting in 2011 included exciting advances in both the core & multidisciplinary forefronts of the study of molecular collision processes. Following the format of the 2009 meeting, we also invited sessions in special topics that involve interfacial dynamics, novel emerging spectroscopies, chemical dynamics in atmospheric, combustion & interstellar environments, as well as a session devoted to theoretical & experimental advances in ultracold molecular samples. Researchers working inside & outside the traditional core topics of the meeting are encouraged to join the conference. We invite contributions of work that seeks understanding of how inter & intra-molecular forces determine the dynamics of the phenomena under study. In addition to invited oral sessions & contributed poster sessions, the scientific program included a formal session consisting of five contributed talks selected from the submitted poster abstracts. The DMC has distinguished itself by having the Herschbach Medal Symposium as part of the meeting format. This tradition of the Herschbach Medal was first started in the 2007 meeting chaired by David Chandler, based on a generous donation of funds & artwork design by Professor Dudley Herschbach himself. There are two such awards made, one for experimental & one for theoretical contributions to the field of Molecular Collision Dynamics, broadly defined. The symposium is always held on the last night of the meeting & has the awardees are asked to deliver an invited lecture on their work. The 2011 Herschbach Medal was dedicated to the contributions of two long standing leaders in Chemical Physics, Professor Yuan T. Lee & Professor George Schatz. Professor Lee’s research has been based on the development & use of advanced chemical kinetics & molecular beams to investigate & manipulate the behavior of fundamental chemical reactions. Lee’s work has been recognized by many awards, including the Nobel Prize for Chemistry in 1986, as well as Sloan Fellow, Dreyfus Scholar, Fellowship in the American Academy of Arts & Sciences, Fellowship in the American Physical Society, Guggenheim Fellow, Member National Academy of Sciences, Member Academia Sinica, E.O. Lawrence Award, Miller Professor, Berkeley, Fairchild Distinguished Scholar, Harrison Howe Award, Peter Debye Award, & the National Medal of Science. Lee also has served as the President of the Academia Sinica in Taiwan (ROC). Professor Schatz’s research group is interested in using theory & computation to describe physical phenomena in a broad range of applications relevant to chemistry, physics, biology & engineering. Among the types of applications that we interested are: optical properties of nanoparticles & nanoparticle assemblies; using theory to model polymer properties; DNA structure, thermodynamics & dynamics; modeling self assembly & nanopatterning; & gas phase reaction dynamics. Among his many awards & distinctions have been appointment as an Alfred P. Sloan Research Fellow, Camille & Henry Dreyfus Teacher-Scholar, the Fresenius Award, Fellow of the American Physical Society, the Max Planck Research Award, Fellowship in the American Association for the Advancement of Science, & election to the International Academy of Quantum Molecular Sciences & the American Academy of Arts & Sciences. Dr Schatz is also lauded for his highly successful work as Editor for the Journal of Physical Chemistry. We requested $10,000 from DOE in support of this meeting. The money was distributed widely among the student & post doctoral fellows & some used to attract the very best scientists in the field. The organizers were committed to encouraging women & minorities as well as encourage the field of Chemical Physics in scientific

  11. Physics & Astronomy Degree options

    E-Print Network [OSTI]

    Brierley, Andrew

    138 Physics & Astronomy Degree options BSc (Single Honours Degrees) Astrophysics Physics MPhys (Single Honours Degrees) Astrophysics Physics Theoretical Physics BSc (Joint Honours Degrees) Physics combinations is under review. MPhys (Joint Honours Degree) Theoretical Physics and Mathematics MSci (Joint

  12. Electron Trapping by Molecular Vibration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Electron Trapping by Molecular Vibration Electron Trapping by Molecular Vibration Print Wednesday, 27 April 2005 00:00 In photoelectron spectroscopy experiments performed at the...

  13. Molecular heat pump

    E-Print Network [OSTI]

    Dvira Segal; Abraham Nitzan

    2005-10-11

    We propose a novel molecular device that pumps heat against a thermal gradient. The system consists of a molecular element connecting two thermal reservoirs that are characterized by different spectral properties. The pumping action is achieved by applying an external force that periodically modulates molecular levels. This modulation affects periodic oscillations of the internal temperature of the molecule and the strength of its coupling to each reservoir resulting in a net heat flow in the desired direction. The heat flow is examined in the slow and fast modulation limits and for different modulation waveforms, thus making it possible to optimize the device performance.

  14. Review of Particle Physics

    E-Print Network [OSTI]

    Nakamura, Kenzo

    2010-01-01

    11. Particle Physics Education Sites . . . . . . . . .ONLINE PARTICLE PHYSICS INFORMATION 1.11. Particle Physics Education Sites . . . . . . . . . . 12.

  15. REVIEW OF PARTICLE PHYSICS

    E-Print Network [OSTI]

    Beringer, Juerg

    2013-01-01

    ONLINE PARTICLE PHYSICS INFORMATION 1.3. Particle Physics Information Platforms . . . . . . . . .14. Particle Physics Education and Outreach

  16. Synthesis, Characterization, and Ultrafast Dynamics of Metal, Metal Oxide, and Semiconductor Nanomaterials

    E-Print Network [OSTI]

    Wheeler, Damon Andreas

    2013-01-01

    Solar Absorption for Photocatalysis with Black Hydrogenatedof physical Chemistry C Photocatalysis of Ag-Loaded TiO 2Lu, G. ; Yates, J. T. , Photocatalysis on TiO2 Surfaces:

  17. Physics | More Science | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics ORNL Physics Environment Safety and Health More Science Home | Science & Discovery | More Science | Physics SHARE Physics Bottom view of the 25 million volt tandem...

  18. Compulsory Elective Theoretical Physics

    E-Print Network [OSTI]

    Dutz, Hartmut

    Aug Sep Compulsory Elective Theoretical Physics (physics606 or - if done previously - 1 module out of physics751, physics754, physics755, physics760, physics7501) 7 cp Specialization (at least 24 cp out of physics61a, -61b, -61c and/or physics62a, -62b, -62c) 24 cp Elective Advanced Lectures (at least 18 cp out

  19. Molecular Cell Short Review

    E-Print Network [OSTI]

    Walter, Nils G.

    '' is the most critical and challenging ques- tion in any murder story, even if it plays out on the molec- ular of an unsolved molecular murder mystery is found in the seemingly simple RNA backbone transesterification

  20. Cellular and Molecular Bioengineering

    E-Print Network [OSTI]

    1 23 Cellular and Molecular Bioengineering ISSN 1865-5025 Volume 6 Number 1 Cel. Mol. Bioeng. (2013,2 and ANATOLY B. KOLOMEISKY 2 1 Department of Bioengineering, Rice University, Houston, TX 77005, USA; and 2

  1. Planetary Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid youOxygen Generation | Center for GasPhysics Physics PrintPicture

  2. 1 Biochemistry and Molecular Medicine BIOCHEMISTRY AND MOLECULAR

    E-Print Network [OSTI]

    Vertes, Akos

    1 Biochemistry and Molecular Medicine BIOCHEMISTRY AND MOLECULAR MEDICINE GRADUATE Master's program · Master of Science in the field of molecular biochemistry and bioinformatics (http://bulletin.gwu.edu/arts-sciences/ biochemistry-molecular-medicine/ms) FACULTY University Professor F. Murad Professors P. Berg, V. Hu, A. Kumar

  3. Physics 4810 / 7810 Teaching and Learning Physics

    E-Print Network [OSTI]

    Maryland at College Park, University of

    Physics 4810 / 7810 Teaching and Learning Physics Fall 2008 Finkelstein A course on how people learn and understand key concepts in physics. Readings in physics, physics education research, education. Useful for all students, especially for those interested in physics, teaching and education research

  4. PHYSICS, B.S. BIOMEDICAL PHYSICS (BIMD)

    E-Print Network [OSTI]

    Hamburger, Peter

    PHYSICS, B.S. BIOMEDICAL PHYSICS (BIMD) (Fall 2015-Summer 2016) IPFW Residency Requirements ______ 3 PHYS 37000 Biomedical Physics Seminar ______ 3 PHYS 41800 Thermal Physics ______ 3 PHYS 44200): ______ ______ ______ ______ ______ ______ #12;PHYSICS, B.S. PLAN--BIOMEDICAL PHYSICS (BIMD) (Fall 2015-Summer 2016) Term: Year: 2015 Term: Year

  5. Physical Protection

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2009-07-23

    This Manual establishes requirements for the physical protection of interests under the U.S. Department of Energys (DOEs) purview ranging from facilities, buildings, Government property, and employees to national security interests such as classified information, special nuclear material (SNM), and nuclear weapons. Cancels Section A of DOE M 470.4-2 Chg 1. Canceled by DOE O 473.3.

  6. Honors, awards, and fellowships Kendall B. Davis Deutsch Award for Excellence in Experimental Physics at MIT

    E-Print Network [OSTI]

    for the APS award for Outstanding Doctoral Thesis Research in Atomic, Molecular, or Optical Physics Tilman in Experimental Physics at MIT Dan M. Stamper-Kurn APS award for Outstanding Doctoral Thesis Research in Atomic for the APS Apker Award, an Undergraduate Physics Achievement Award W. Ketterle Nobel Prize in Physics

  7. Mathematics and Physics

    E-Print Network [OSTI]

    $author.value

    Associate Professor of Mathematics and Physics Website: [Webpage] [Bio] ... Research Interests: mathematical physics, condensed matter theory ...

  8. Computational Physics on Graphics Processing Units

    E-Print Network [OSTI]

    Ari Harju; Topi Siro; Filippo Federici-Canova; Samuli Hakala; Teemu Rantalaiho

    2013-03-06

    The use of graphics processing units for scientific computations is an emerging strategy that can significantly speed up various different algorithms. In this review, we discuss advances made in the field of computational physics, focusing on classical molecular dynamics, and on quantum simulations for electronic structure calculations using the density functional theory, wave function techniques, and quantum field theory.

  9. Computational Physics on Graphics Processing Units

    E-Print Network [OSTI]

    Harju, Ari; Federici-Canova, Filippo; Hakala, Samuli; Rantalaiho, Teemu

    2012-01-01

    The use of graphics processing units for scientific computations is an emerging strategy that can significantly speed up various different algorithms. In this review, we discuss advances made in the field of computational physics, focusing on classical molecular dynamics, and on quantum simulations for electronic structure calculations using the density functional theory, wave function techniques, and quantum field theory.

  10. High Energy Physics and Nuclear Physics Network Requirements

    E-Print Network [OSTI]

    Dart, Eli

    2014-01-01

    High Energy Physics and Nuclear Physics Network RequirementsCalifornia. High Energy Physics and Nuclear Physics Networkof High Energy Physics and Nuclear Physics, DOE Office of

  11. Physical Protection

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2005-08-26

    This Manual establishes requirements for the physical protection of safeguards and security interests. Copies of Section B, Safeguards and Security Alarm Management System, which contains Unclassified Controlled Nuclear Information, and Appendix 1, Security Badge Specifications, which contains Official Use Only information, are only available, by request, from the program manager, Protection Program Operations, 301-903-6209. Chg 1, dated 3/7/06. Cancels: DOE M 473.1-1 and DOE M 471.2-1B

  12. Physical Protection

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2005-08-26

    Establishes requirements for the physical protection of safeguards and security interests. Copies of Section B, Safeguards and Security Alarm Management System, which contains Unclassified Controlled Nuclear Information, and Appendix 1, Security Badge Specifications, which contains Official Use Only information, are only available, by request, from the program manager, Protection Program Operations, 301-903-6209. Cancels: DOE M 473.1-1 and DOE M 471.2-1B.

  13. Coherent effects in atomic and molecular media: applications to anthrax detection and quantum information 

    E-Print Network [OSTI]

    Sariyanni, Zoe-Elizabeth

    2006-10-30

    In the present quantum optics and laser physics study, the non-linear interaction of electromagnetic fields with atomic, molecular and biomolecular media is analyzed. Particular emphasis is given to coherent phenomena, while propagation...

  14. Self-doped molecular composite battery electrolytes

    DOE Patents [OSTI]

    Harrup, Mason K.; Wertsching, Alan K.; Stewart, Frederick F.

    2003-04-08

    This invention is in solid polymer-based electrolytes for battery applications. It uses molecular composite technology, coupled with unique preparation techniques to render a self-doped, stabilized electrolyte material suitable for inclusion in both primary and secondary batteries. In particular, a salt is incorporated in a nano-composite material formed by the in situ catalyzed condensation of a ceramic precursor in the presence of a solvated polymer material, utilizing a condensation agent comprised of at least one cation amenable to SPE applications. As such, the counterion in the condensation agent used in the formation of the molecular composite is already present as the electrolyte matrix develops. This procedure effectively decouples the cation loading levels required for maximum ionic conductivity from electrolyte physical properties associated with condensation agent loading levels by utilizing the inverse relationship discovered between condensation agent loading and the time domain of the aging step.

  15. Molecular Physics Vol. 108, Nos. 1920, 1020 October 2010, 25792590

    E-Print Network [OSTI]

    Helgaker, Trygve

    ­orbit (PSO) term, the spin­dipole (SD) term, and the Fermi-contact (FC) term [1]. Whereas the DSO and PSO

  16. Molecular Imaging: Physics and Bioapplications of Quantum Dots

    E-Print Network [OSTI]

    Michalet, Xavier

    the tech- niques used to interface these inorganic materials to the bio- logical world. It concludes 8.3.6 Lasers, LED, and Photovoltaic Cells 117 8.4 Synthesis of Colloidal Nanocrystals 119 8.4.1 Synthesis 119 8.4.2 Solubilization 120 8.4.3 Functionalization 121 8.5 Applications of Quantum Dot

  17. Physics 3343: Modern Physics Spring 2013

    E-Print Network [OSTI]

    Diestel, Geoff

    Physics 3343: Modern Physics Spring 2013 Professor: Dr. Daniel K. Marble Office: SCI 213E Telephone: Science 232 Textbooks: Required: 1) Modern Physics 3rd Edition by Serway, Moses, and Moyer 2) Schaum's Outline Series: Modern Physics by Gautreau and Savin Recommended: 1) Quantum Physics of Atoms, Atoms

  18. School of Physics & Astronomy Physics Colloquium

    E-Print Network [OSTI]

    Richmond, Michael W.

    School of Physics & Astronomy Physics Colloquium Abstract: Physics degree holders are among and Technology employers know that with a physics training, a poten- tial hire has acquired a broad problem. Therefore it's no surprise that the majority of physics graduates find employment in private

  19. Physics 480 Introduction to Solid State Physics

    E-Print Network [OSTI]

    Kioussis, Nicholas

    Physics 480 Introduction to Solid State Physics Spring 2012 Logistics Lecture Room: 1100 (Live Oak://www.csun.edu/~nkioussi Prerequisites Quantum Mechanics or Modern Physics at 375 level Textbook Introduction to Solid State Physics, Charles Kittel, Wiley, 8th Edition Reference: Neil W. Ashcroft and N. David Mermin, Solid State Physics

  20. PHYSICS OF BURNING PHYSICS INACCESSIBLE TO

    E-Print Network [OSTI]

    ;OUTLINE · Introduction · Three Classes of Burning Plasma Physics inaccessable to contemporary tokamak of inaccessable burning plasma physics · Conclusions FIRE Workshop 2 May 2000 #12;INTRODUCTION · A fusion reactorPHYSICS OF BURNING PLASMAS: PHYSICS INACCESSIBLE TO PRESENT FACILITIES FIRE Physics Workshop May

  1. Time optimization and state-dependent constraints in the quantum optimal control of molecular orientation

    E-Print Network [OSTI]

    M. Ndong; C. Koch; D. Sugny

    2013-08-03

    We apply two recent generalizations of monotonically convergent optimization algorithms to the control of molecular orientation by laser fields. We show how to minimize the control duration by a step-wise optimization and maximize the field-free molecular orientation using state-dependent constraints. We discuss the physical relevance of the different results.

  2. Microelectronics Journal 39 (2008) 190201 Prototyping bio-nanorobots using molecular dynamics simulation and

    E-Print Network [OSTI]

    Mavroidis, Constantinos

    2008-01-01

    Abstract This paper presents a molecular mechanics study using a molecular dynamics software (NAMD) coupled-nano environments in VR, the operator can design and characterize through physical simulation and 3D visualization) in their native environment. Their use as elementary bio-nanorobotic components are also simulated and the results

  3. Cyanide Bridged Molecular Magnetic Materials with Anisotropic Transition Metal Ions: Investigation of Bistable Magnetic Phenomena 

    E-Print Network [OSTI]

    Avendano, Carolina

    2011-08-08

    ......................................................................................................................... 257 xii LIST OF FIGURES Page Figure 1.1 Schematic molecular spintronics based... and electronic degrees of freedom. This field, dubbed ?spintronics?,12-15 encompasses a range of novel applications for magnetic materials (Figure 1.1). Research in molecular magnetism has spawned a new collaborative spirit between the physical and chemical...

  4. Probing Interactions in Complex Molecular Systems through Ordered Assembly

    SciTech Connect (OSTI)

    De Yoreo, J J; Bartelt, M C; Orme, C A; Villacampa, A; Weeks, B L; Miller, A E

    2002-01-31

    Emerging from the machinery of epitaxial science and chemical synthesis, is a growing emphasis on development of self-organized systems of complex molecular species. The nature of self-organization in these systems spans the continuum from simple crystallization of large molecules such as dendrimers and proteins, to assembly into large organized networks of nanometer-scale structures such as quantum dots or nanoparticles. In truth, self-organization in complex molecular systems has always been a central feature of many scientific disciplines including fields as diverse as structural biology, polymer science and geochemistry. But over the past decade, changes in those fields have often been marked by the degree to which researchers are using molecular-scale approaches to understand the hierarchy of structures and processes driven by this ordered assembly. At the same time, physical scientists have begun to use their knowledge of simple atomic and molecular systems to fabricate synthetic self-organized systems. This increasing activity in the field of self-organization is testament to the success of the physical and chemical sciences in building a detailed understanding of crystallization and epitaxy in simple atomic and molecular systems, one that is soundly rooted in thermodynamics and chemical kinetics. One of the fundamental challenges of chemistry and materials science in the coming decades is to develop a similarly well-founded physical understanding of assembly processes in complex molecular systems. Over the past five years, we have successfully used in situ atomic force microscopy (AFM) to investigate the physical controls on single crystal epitaxy from solutions for a wide range of molecular species. More recently, we have combined this method with grazing incidence X-ray diffraction and kinetic Monte Carlo modeling in order to relate morphology to surface atomic structure and processes. The purpose of this proposal was to extend this approach to assemblies of three classes of ''super molecular'' nanostructured materials. These included (1) dendrimers, (2) DNA bonded nano-particles, and (3) colloids, all of which form solution-based self-organizing systems. To this end, our goals were, first, to learn how to modify models of epitaxy in small molecule systems so that they are useful, efficient, and applicable to assembly of super-molecular species; and, second, to learn how systematic variations in the structure and bonding of the building blocks affect the surface kinetics and energetics that control the assembly process and the subsequent dynamic behavior of the assembled structures. AFM imaging provided experimental data on morphology and kinetics, while kinetic Monte Carlo (KMC) simulations related these data to molecular-scale processes and features.

  5. Physical Sciences

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesseworkSURVEYI/OPerformance andAreaPhotoinducedCenter Objective ThePhysical

  6. Theoretical Determination of the Dissociation Energy of Molecular Hydrogen

    E-Print Network [OSTI]

    Pachucki, Krzysztof

    Theoretical Determination of the Dissociation Energy of Molecular Hydrogen Konrad Piszczatowski that this system is stable against the dissociation to two hydrogen atoms. The ap- proximate dissociation energy Physics, University of Warsaw, Hoza 69, 00-681 Warsaw, Poland Abstract The dissociation energy

  7. Casting polymer nets to optimize noisy molecular codes

    E-Print Network [OSTI]

    Tlusty, Tsvi

    Casting polymer nets to optimize noisy molecular codes Tsvi Tlusty* Department of Physics noise may be understood from the sta- tistics of a two-dimensional network made of polymers. The noisy. The ``polymers'' are the boundaries between these regions, and their statistics define the cost and the quality

  8. Ultrafast crystalline-to-amorphous phase transition in Ge{sub 2}Sb{sub 2}Te{sub 5} chalcogenide alloy thin film using single-shot imaging spectroscopy

    SciTech Connect (OSTI)

    Takeda, Jun, E-mail: jun@ynu.ac.jp; Oba, Wataru; Minami, Yasuo; Katayama, Ikufumi [Department of Physics, Graduate School of Engineering, Yokohama National University, Yokohama 240-8501 (Japan); Saiki, Toshiharu [Graduate School of Science and Technology, Keio University, Yokohama 223-8522 (Japan)

    2014-06-30

    We have observed an irreversible ultrafast crystalline-to-amorphous phase transition in Ge{sub 2}Sb{sub 2}Te{sub 5} chalcogenide alloy thin film using broadband single-shot imaging spectroscopy. The absorbance change that accompanied the ultrafast amorphization was measured via single-shot detection even for laser fluences above the critical value, where a permanent amorphized mark was formed. The observed rise time to reach the amorphization was found to be ?130–200 fs, which was in good agreement with the half period of the A{sub 1} phonon frequency in the octahedral GeTe{sub 6} structure. This result strongly suggests that the ultrafast amorphization can be attributed to the rearrangement of Ge atoms from an octahedral structure to a tetrahedral structure. Finally, based on the dependence of the absorbance change on the laser fluence, the stability of the photoinduced amorphous phase is discussed.

  9. Cell Reports Molecular Architecture

    E-Print Network [OSTI]

    Harrison, Stephen C.

    Cell Reports Report Molecular Architecture of the Yeast Monopolin Complex Kevin D. Corbett1 report here biochemical characterization of the monopolin complex subunits Mam1 and Hrr25). In these organisms, sister kinetochore co-orientation in meiosis I depends on the Aurora B/Ipl1 kinase, as well

  10. NuSTAR Reveals Relativistic Reflection But No Ultra-Fast Outflow In The Quasar PG 1211+143

    E-Print Network [OSTI]

    Zoghbi, A; Walton, D J; Harrison, F A; Fabian, A C; Reynolds, C S; Boggs, S E; Christensen, F E; Craig, W; Hailey, C J; Stern, D; Zhang, W W

    2015-01-01

    We report on four epochs of observations of the quasar PG 1211+143 using NuSTAR. The net exposure time is 300 ks. Prior work on this source found suggestive evidence of an 'ultra-fast outflow' (or, UFO) in the Fe K band, with a velocity of approximately 0.1c. The putative flow would carry away a high mass flux and kinetic power, with broad implications for feedback and black hole-galaxy co-evolution. NuSTAR detects PG 1211+143 out to 30 keV, meaning that the continuum is well-defined both through and above the Fe K band. A characteristic relativistic disk reflection spectrum is clearly revealed, via a broad Fe K emission line and Compton back-scattering curvature. The data offer only weak constraints on the spin of the black hole. A careful search for UFO's show no significant absorption feature above 90% confidence. The limits are particularly tight when relativistic reflection is included. We discuss the statistics and the implications of these results in terms of connections between accretion onto quasars,...

  11. Optimization of chemical compositions in low-carbon Al-killed enamel steel produced by ultra-fast continuous annealing

    SciTech Connect (OSTI)

    Dong, Futao; Du, Linxiu; Liu, Xianghua; Xue, Fei

    2013-10-15

    The influence of Mn,S and B contents on microstructural characteristics, mechanical properties and hydrogen trapping ability of low-carbon Al-killed enamel steel was investigated. The materials were produced and processed in a laboratory and the ultra-fast continuous annealing processing was performed using a continuous annealing simulator. It was found that increasing Mn,S contents in steel can improve its hydrogen trapping ability which is attributed by refined ferrite grains, more dispersed cementite and added MnS inclusions. Nevertheless, it deteriorates mechanical properties of steel sheet. Addition of trace boron results in both good mechanical properties and significantly improved hydrogen trapping ability. The boron combined with nitrogen segregating at grain boundaries, cementite and MnS inclusions, provides higher amount of attractive hydrogen trapping sites and raises the activation energy for hydrogen desorption from them. - Highlights: • We study microstructures and properties in low-carbon Al-killed enamel steel. • Hydrogen diffusion coefficients are measured to reflect fish-scale resistance. • Manganese improves hydrogen trapping ability but decrease deep-drawing ability. • Boron improves both hydrogen trapping ability and deep-drawing ability. • Both excellent mechanical properties and fish-scale resistance can be matched.

  12. Study of beam loading and its compensation in the Compact Ultrafast Terahertz Free-Electron Laser injector linac

    SciTech Connect (OSTI)

    Lal, Shankar Pant, K. K.

    2014-12-15

    The RF properties of an accelerating structure, and the pulse structure and charge per bunch in the electron beam propagating through it are important parameters that determine the impact of beam loading in the structure. The injector linac of the Compact Ultrafast Terahertz Free-Electron Laser (CUTE-FEL) has been operated with two different pulse structures during initial commissioning experiments and the effect of beam loading on the accelerated electron beam parameters has been studied analytically for these two pulse structures. This paper discusses the analytical study of beam loading in a Standing Wave, Plane Wave Transformer linac employed in the CUTE-FEL setup, and a possible technique for its compensation for the electron beam parameters of the CUTE-FEL. A parametric study has been performed to study beam loading for different beam currents and to optimize injection time of the electron beam to compensate beam loading. Results from the parametric study have also been used to explain previously observed results from acceleration experiments in the CUTE-FEL setup.

  13. A dynamic and ultrafast group delay tuning mechanism in two microcavities side-coupled with a waveguide system

    SciTech Connect (OSTI)

    Wang, Boyun; Wang, Tao, E-mail: wangtao@hust.edu.cn; Tang, Jian; Li, Xiaoming; Zhu, Youjiang [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-10-07

    We theoretically propose a dynamic and ultrafast group delay tuning mechanism in two microcavities side-coupled to a waveguide system through external optical pump beams. The optical Kerr effect modulation method is applied to improve tuning rate with response time of subpicoseconds or even femtoseconds. The group delay of an all-optical analog to electromagnetically induced transparency effect can be controlled by tuning either the frequency of photonic crystal microcavities or the propagation phase of line waveguide. Group delay is controlled between 5.88 and 70.98 ps by dynamically tuning resonant frequencies of the microcavities. Alternatively, the group delay is controlled between 1.86 and 12.08 ps by dynamically tuning the propagation phase of line waveguide. All observed schemes are analyzed rigorously through finite-difference time-domain simulations and coupled-mode formalism. Results show a new direction toward microstructure integration optical pulse trapping and all-optical dynamical storage of light devices in optical communication and quantum information processing.

  14. Single shot ultrafast dynamic ellipsometry (UDE) of laser-driven shocks in single crystal explosives

    SciTech Connect (OSTI)

    Whitley, Von H; Mcgrane, Shawn D; Moore, David S; Eakins, Dan E; Bolme, Cindy A

    2009-01-01

    We report on the first experiments to measure states in shocked energetic single crystals with dynamic ellipsometry. We demonstrate that these ellipsometric techniques can produce reasonable Hugoniot values using small amounts of crystalline RDX and PETN. Pressures, particle velocities and shock velocities obtained using shocked ellipsometry are comparable to those found using gas-gun flyer plates and molecular dynamics calculations. The adaptation of the technique from uniform thin films of polymers to thick non-perfect crystalline materials was a significant achievement. Correct sample preparation proved to be a crucial component. Through trial and error, we were able to resolve polishing issues, sample quality problems, birefringence effects and mounting difficulties that were not encountered using thin polymer films.

  15. Center for Beam Physics

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2010-01-01

    for Heavy Ion Fusion," Research Trends in Physics, La JollaInternational School of Physics, New York, New York (1992),Professor and Chairman Physics Department University of

  16. Particle Physics Booklet 2008

    E-Print Network [OSTI]

    et al., C. Amsler

    2008-01-01

    212 25. Accelerator physics of colliders ? 26. High-energythe full Review. PARTICLE PHYSICS BOOKLET TABLE OF CONTENTSrev. ) Summary Tables of Particle Physics Gauge and Higgs

  17. Center for Beam Physics

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2010-01-01

    presented at APS Division of Plasma Physics, Denver,of Division of Physics of Beams of APS, InternationalLinear Colliders," APS New Directions in High Energy Physics

  18. Molecular Gas in Early-type Galaxies

    E-Print Network [OSTI]

    Alatalo, Katherine Anne

    2012-01-01

    toward the center (first seen in the molecular gas in A+3.4 Molecular Gas Mass . . . . . . .of the molecular gas . . . . . . . . . . 2.4.3 Mass of

  19. PIA - Environmental Molecular Sciences Laboratory (EMSL) User...

    Energy Savers [EERE]

    Molecular Sciences Laboratory (EMSL) User System (ESU) PIA - Environmental Molecular Sciences Laboratory (EMSL) User System (ESU) PIA - Environmental Molecular Sciences Laboratory...

  20. Metal-mediated molecular machines 

    E-Print Network [OSTI]

    Howgego, David Christopher

    2013-06-29

    Nature abounds with ingenious nanoscopic machines employed to carry out all of the requisite tasks that collectively contribute to the molecular basis of life. This thesis focuses primarily on a sub-set known as "molecular ...

  1. POSITION ANNOUNCEMENT Insect Molecular Biology

    E-Print Network [OSTI]

    Ishida, Yuko

    POSITION ANNOUNCEMENT Insect Molecular Biology 03/21/2014 POSITION: Research Associate LOCATION in entomology, biochemistry, molecular biology and/or toxicology; extensive research experience in entomology, biochemistry, cell biology and/or molecular biology; excellent organizational, and written and interpersonal

  2. Physics Illinois Undergraduate Programs

    E-Print Network [OSTI]

    Lee, Tonghun

    Physics Illinois Undergraduate Programs Department of Physics College of Engineering University to undergraduate education. Over the last 15 years, in collaboration with our nationally recognized Physics Education Research Group, our faculty has reinvented the way undergraduate physics courses are taught

  3. Molecular-beam scattering

    SciTech Connect (OSTI)

    Vernon, M.F.

    1983-07-01

    The molecular-beam technique has been used in three different experimental arrangements to study a wide range of inter-atomic and molecular forces. Chapter 1 reports results of a low-energy (0.2 kcal/mole) elastic-scattering study of the He-Ar pair potential. The purpose of the study was to accurately characterize the shape of the potential in the well region, by scattering slow He atoms produced by expanding a mixture of He in N/sub 2/ from a cooled nozzle. Chapter 2 contains measurements of the vibrational predissociation spectra and product translational energy for clusters of water, benzene, and ammonia. The experiments show that most of the product energy remains in the internal molecular motions. Chapter 3 presents measurements of the reaction Na + HCl ..-->.. NaCl + H at collision energies of 5.38 and 19.4 kcal/mole. This is the first study to resolve both scattering angle and velocity for the reaction of a short lived (16 nsec) electronic excited state. Descriptions are given of computer programs written to analyze molecular-beam expansions to extract information characterizing their velocity distributions, and to calculate accurate laboratory elastic-scattering differential cross sections accounting for the finite apparatus resolution. Experimental results which attempted to determine the efficiency of optically pumping the Li(2/sup 2/P/sub 3/2/) and Na(3/sup 2/P/sub 3/2/) excited states are given. A simple three-level model for predicting the steady-state fraction of atoms in the excited state is included.

  4. Physics 291: Physics Science Outreach Information

    E-Print Network [OSTI]

    Baski, Alison

    Physics 291: Physics Science Outreach Course Information Fall 2005 Information (course on General Education List K - Urban) Phys291: Topic - Physical Science Outreach - Richmond Elementary (#14917) Time: Tues & Thurs at 11:00 am to 12:15 pm (plus outreach visits) Location: OLVPH #2121 (located in Physics

  5. Color Imaging Arithmetic: Physics Math > Physics + Math

    E-Print Network [OSTI]

    Sharma, Gaurav

    Color Imaging Arithmetic: Physics Math > Physics + Math Gaurav Sharma University of Rochester inter- action commonly form the physical interface by which we connect to the digital cyber-world. Because these devices bridge the physical and the electronic worlds, elegant and effective solutions

  6. People's Physics Book The People's Physics Book

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    #12;People's Physics Book The People's Physics Book Authors James H. Dann, Ph.D. James J. Dann. All rights reserved. Textbook Website http://scipp.ucsc.edu/outreach/index2.html #12;People's Physics) "Each discovery, each advance, each increase in the sum of human riches, owes its being to the physical

  7. Physics Procedia 00 (2013) 16 Physics Procedia

    E-Print Network [OSTI]

    Adler, Joan

    2013-01-01

    Physics Procedia 00 (2013) 1­6 Physics Procedia Educating the next generation of Computational Physicists Joan Adler Physics Department, Technion -IIT, Haifa, Israel, 32000 Abstract Many "senior" Computational Physics researchers began their careers perched on of the other vertices of the Landau triangle

  8. People's Physics Book The People's Physics Book

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    People's Physics Book The People's Physics Book Authors James H. Dann, Ph.D. James J. Dann. All rights reserved. Textbook Website http://scipp.ucsc.edu/outreach/index2.html #12;People's Physics) "Each discovery, each advance, each increase in the sum of human riches, owes its being to the physical

  9. Physics Procedia 00 (2013) 15 Physics Procedia

    E-Print Network [OSTI]

    Adler, Joan

    2013-01-01

    Physics Procedia 00 (2013) 1­5 Physics Procedia Educating the next generation of Computational Physicists Joan Adler Physics Department, Technion -IIT, Haifa, Israel, 32000 Abstract Many "senior" Computational Physics researchers began their careers perched on of the other vertices of the Landau triangle

  10. Physics 129 Nuclear and Particle Physics

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Physics 129 Nuclear and Particle Physics Winter Quarter 2008 Instructor: David A. Williams (office Physics by W. S. C. Williams, Oxford University Press, 1991. Course materials Homework assignments materials will be distributed on the web site above. Nine texts on nuclear and particle physics, all

  11. Physics 375 Introduction to Quantum Physics

    E-Print Network [OSTI]

    Kioussis, Nicholas

    Physics 375 Introduction to Quantum Physics Fall 2006 Logistics Lecture Room: LO 1100 (Science I, 1 Phone: 818 677-7733 e-mail: nick.kioussis@csun.edu http://www.csun.edu/~nkioussi/ Prerequisites Physics 227 ­ Calculus based course on Thermodynamics, Waves, and Modern Physics Textbook Introductory Quantum

  12. January 2010 Physics 3300

    E-Print Network [OSTI]

    deYoung, Brad

    1 January 2010 Physics 3300 Introduction to Physical Oceanography Instructor: Brad de Young Physics and Physical Oceanography Memorial University, bdeyoung@mun.ca Room C-3000 737-8738 Physics 3300 Introduction? What's next? Texts : Robert H. Stewart, Introduction to Physical Oceanography, Robert H. Stewart

  13. Mathematics and Physics

    E-Print Network [OSTI]

    Sengun, Mehmet Haluk

    knowledge of mathematics and physics after you graduate." 3thE UnivErsity Of warwick Introduction #12;TheMathematics and Physics Physics at warwick 2016 #12;Physics at Warwick Joint Honours Courses Mathematics and Physics #12;Gary Barker head, Undergraduate admissions "Mathematics and physics are a sensible

  14. Outflow Driven Turbulence in Molecular Clouds

    E-Print Network [OSTI]

    Jonathan J. Carroll; Adam Frank; Eric G. Blackman; Andrew J. Cunningham; Alice C. Quillen

    2008-05-30

    In this paper we explore the relationship between protostellar outflows and turbulence in molecular clouds. Using 3-D numerical simulations we focus on the hydrodynamics of multiple outflows interacting within a parsec scale volume. We explore the extent to which transient outflows injecting directed energy and momentum into a sub-volume of a molecular cloud can be converted into random turbulent motions. We show that turbulence can readily be sustained by these interactions and show that it is possible to broadly characterize an effective driving scale of the outflows. We compare the velocity spectrum obtained in our studies to that of isotropically forced hydrodynamic turbulence finding that in outflow driven turbulence a power law is indeed achieved. However we find a steeper spectrum (beta ~ 3) is obtained in outflow driven turbulence models than in isotropically forced simulations (beta ~ 2). We discuss possible physical mechanisms responsible for these results as well and their implications for turbulence in molecular clouds where outflows will act in concert with other processes such as gravitational collapse.

  15. Hydrogen bond rearrangements and the motion of charge defects in water viewed using multidimensional ultrafast infrared spectroscopy

    E-Print Network [OSTI]

    Roberts, Sean T. (Sean Thomas)

    2010-01-01

    Compared with other molecular liquids, water is highly structured due to its ability to form up to four hydrogen bonds to its nearest neighbors, resulting in a tetrahedral network of molecules. However, this network is ...

  16. Sandia Energy - Molecular Geochemistry

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II)Geothermal Energy &Water Power&Grid ActionModelingMolecular

  17. Assessment of Molecular Modeling & Simulation

    SciTech Connect (OSTI)

    2002-01-03

    This report reviews the development and applications of molecular and materials modeling in Europe and Japan in comparison to those in the United States. Topics covered include computational quantum chemistry, molecular simulations by molecular dynamics and Monte Carlo methods, mesoscale modeling of material domains, molecular-structure/macroscale property correlations like QSARs and QSPRs, and related information technologies like informatics and special-purpose molecular-modeling computers. The panel's findings include the following: The United States leads this field in many scientific areas. However, Canada has particular strengths in DFT methods and homogeneous catalysis; Europe in heterogeneous catalysis, mesoscale, and materials modeling; and Japan in materials modeling and special-purpose computing. Major government-industry initiatives are underway in Europe and Japan, notably in multi-scale materials modeling and in development of chemistry-capable ab-initio molecular dynamics codes.

  18. Traffic of Molecular Motors

    E-Print Network [OSTI]

    Stefan Klumpp; Melanie J. I. Müller; Reinhard Lipowsky

    2005-12-06

    Molecular motors perform active movements along cytoskeletal filaments and drive the traffic of organelles and other cargo particles in cells. In contrast to the macroscopic traffic of cars, however, the traffic of molecular motors is characterized by a finite walking distance (or run length) after which a motor unbinds from the filament along which it moves. Unbound motors perform Brownian motion in the surrounding aqueous solution until they rebind to a filament. We use variants of driven lattice gas models to describe the interplay of their active movements, the unbound diffusion, and the binding/unbinding dynamics. If the motor concentration is large, motor-motor interactions become important and lead to a variety of cooperative traffic phenomena such as traffic jams on the filaments, boundary-induced phase transitions, and spontaneous symmetry breaking in systems with two species of motors. If the filament is surrounded by a large reservoir of motors, the jam length, i.e., the extension of the traffic jams is of the order of the walking distance. Much longer jams can be found in confined geometries such as tube-like compartments.

  19. Physics Resources for Teachers

    E-Print Network [OSTI]

    Collar, Juan I.

    Physics Resources for Teachers University of Wisconsin ­ Madison Department of Physics 1150 University Ave. Madison, WI 53706 wonders@physics.wisc.edu (608) 262-2927 Plasma Physics Web Resources Center Plasma Physics Lab http://science-education.pppl.gov/ Coalition for Plasma Science http

  20. General Syllabus Physics 45100

    E-Print Network [OSTI]

    Brinkmann, Peter

    General Syllabus Physics 45100 Thermodynamics and Statistical Physics Designation: Undergraduate Catalog description: 45100: Thermodynamics and Statistical Physics Temperature; equation of state; work and statistical mechanics; low-temperature physics; the Third Law. 3 HR./Wk.; 3 CR. Prerequisites: Physics 35100

  1. B Physics (Experiment)

    E-Print Network [OSTI]

    Michal Kreps

    2010-08-13

    In past few years the flavor physics made important transition from the work on confirmation the standard model of particle physics to the phase of search for effects of a new physics beyond standard model. In this paper we review current state of the physics of b-hadrons with emphasis on results with a sensitivity to new physics.

  2. DOCTORAL PROGRAMME MATHEMATICS AND PHYSICS, Subprogramme PHYSICS,

    E-Print Network [OSTI]

    ?umer, Slobodan

    area. The nuclear Engineering module treats nuclear technology, operation, nuclear safety, reactorDOCTORAL PROGRAMME MATHEMATICS AND PHYSICS, Subprogramme PHYSICS, Module NUCLEAR ENGINEERING Slovenia is producing a significant share of its electricity in nuclear power plant. The doctoral programme

  3. Lubricant characterization by molecular simulation

    SciTech Connect (OSTI)

    Moore, J.D.; Cui, S.T.; Cummings, P.T.; Cochran, H.D.

    1997-12-01

    The authors have reported the calculation of the kinematic viscosity index of squalane from nonequilibrium molecular dynamics simulations. This represents the first accurate quantitative prediction of this measure of lubricant performance by molecular simulation. Using the same general alkane potential model, this computational approach offers the possibility of predicting the performance of potential lubricants prior to synthesis. Consequently, molecular simulation is poised to become an important tool for future lubricant development.

  4. Shock and Detonation Physics at Los Alamos National Laboratory

    SciTech Connect (OSTI)

    Robbins, David L; Dattelbaum, Dana M; Sheffield, Steve A

    2012-08-22

    WX-9 serves the Laboratory and the Nation by delivering quality technical results, serving customers that include the Nuclear Weapons Program (DOE/NNSA), the Department of Defense, the Department of Homeland Security and other government agencies. The scientific expertise of the group encompasses equations-of-state, shock compression science, phase transformations, detonation physics including explosives initiation, detonation propagation, and reaction rates, spectroscopic methods and velocimetry, and detonation and equation-of-state theory. We are also internationally-recognized in ultra-fast laser shock methods and associated diagnostics, and are active in the area of ultra-sensitive explosives detection. The facility capital enabling the group to fulfill its missions include a number of laser systems, both for laser-driven shocks, and spectroscopic analysis, high pressure gas-driven guns and powder guns for high velocity plate impact experiments, explosively-driven techniques, static high pressure devices including diamond anvil cells and dilatometers coupled with spectroscopic probes, and machine shops and target fabrication facilities.

  5. Historical Approach to Physics according to Kant, Einstein, and Hegel

    E-Print Network [OSTI]

    Kim, Y S

    2013-01-01

    It is known that Einstein's conceptual base for his theory of relativity was the philosophy formulated by Immanuel Kant. Things appear differently to observers in different frames. However, Kant's Ding-an-Sich leads to the existence of the absolute reference frame which is not acceptable in Einstein's theory. It is possible to avoid this conflict using the ancient Chinese philosophy of Taoism where two different views can co-exist in harmony. This is not enough to explain Einstein's discovery of the mass-energy relation. The energy-momentum relations for slow and ultra-fast particles take different forms. Einstein was able to synthesize these two formulas to create his energy-mass relation. Indeed, this is what Hegelianism is about in physics. Isaac Newton synthesized open orbits for comets and closed orbits for planets to create his second law of motion. Maxwell combined electricity and magnetism to create his four equations to the present-day wireless world. In order to synthesize wave and particle views of...

  6. Electron Trapping by Molecular Vibration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Electron Trapping by Molecular Vibration Print In photoelectron spectroscopy experiments performed at the ALS, a group of researchers has found that electronic transitions normally...

  7. Electron Trapping by Molecular Vibration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    types of molecular vibrations. Specifically, they found that when the symmetry of a linear triatomic molecule is broken by asymmetric vibrational modes, photoelectrons can...

  8. Molecular Cell Hydroxyurea Induces Hydroxyl

    E-Print Network [OSTI]

    Collins, James J.

    Molecular Cell Article Hydroxyurea Induces Hydroxyl Radical-Mediated Cell Death in Escherichia coli superoxide production, together with the increased iron uptake, fuels the formation of hydroxyl radicals

  9. Physics 100B General Physics II

    E-Print Network [OSTI]

    Kioussis, Nicholas

    and Magnetic fields, Currents and circuits, Electromagnetic fields, Optics, Special Theory of Relativity an understanding and appreciation of the fundamental laws of electricity, magnetism and modern physics. At the end, Quantum Theory, Atomic physics, Nuclear Physics, and Elementary particles. (Chapters 19-31) Requirement

  10. Physical Education ! Teaching Materials!

    E-Print Network [OSTI]

    Burg, Theresa

    Physical Education ! Teaching Materials! !!! ! 1. PROGRAMS OF STUDY ! ! ! ! ! ! ! ! ! !P.E. Program Physical Activity (DPA) Initiative: Mandatory program introduced in 2005. Schools are required to create opportunities for students to engage in Physical activity. Administrators and all teachers are responsible

  11. ENVIRONMENTAL PHYSICS METHODS

    E-Print Network [OSTI]

    Horváth, Ákos

    ENVIRONMENTAL PHYSICS METHODS LABORATORY PRACTICES #12;Foundations of Environmental Science Lecture Enviromental Physics Methods Laboratory Practices #12;Eötvös Loránd University Faculty of Science ENVIRONMENTAL tankönyvsorozat" (KMR Foundations of Environmental Science Lecture Series). KEYWORDS: Environmental physics

  12. Ultrafast optical pump-probe spectroscopy is used to reveal the coexistence of coupled antiferromagnetic (AFM)/ferroelectric (FE) and ferromagnetic (FM) orders in multiferroic TbMnO3 films, which can guide researchers in creating new kinds of multiferroic materials.

    SciTech Connect (OSTI)

    Qi, Jingbo; Zhu, Jianxin; Trugman, Stuart A.; Taylor, Antoinette; Jia, Quanxi; Prasankumar, Rohit

    2012-07-06

    Multiferroic materials have attracted much interest in the past decade, due not only to their novel device applications, but also their manifestations of coupling and interactions between different order parameters (particularly electric polarization and magnetic order). Recently, much attention has been focused on perovskite manganites, RMnO{sub 3} (R = rare earth ions), due to the discovery of a large magnetoelectric effect in these materials. The first member of this family to be discovered was TbMnO{sub 3} (TMO), which is now well established as a typical magnetoelectric multiferroic. Extensive experimental and theoretical studies have already been done on single crystal TMO (SC-TMO). In brief, SC-TMO, with a distorted orthorhombic perovskite structure, has an antiferromagnetic (AFM) phase transition at T{sub N} {approx}40 K with sinusoidally ordered Mn moments. Below T{sub FE} {approx} 28 K, ferroelectric (FE) order develops owing to the appearance of cycloidal spiral spin structure. In contrast, there are relatively few reports describing the properties of TMO thin films (typically grown on SrTiO{sub 3} (STO) substrates). In general, thin films can enable new functionality in materials, as their physical parameters can be changed by modifying their structure via strain imposed by the substrate. Strain in particular has the potential to directly couple FE and FM orders, which is very rare. This could benefit electronic device applications by providing low power consumption, high speed operation, and greater electric/magnetic field controllability. Previous investigations of magnetic properties in TMO films revealed an unexpected ferromagnetic (FM) order, in contrast to SC-TMO. However, several important questions regarding these films are still unanswered for instance: (1) What mechanism induces FM order? (2) Can FM, sinusoidal AFM and spiral AFM (or FE) orders coexist? (3) Can FM order be coupled to FE order? To fully understand these unique materials, experimental techniques capable of dynamically unraveling the interplay between these degrees of freedom on an ultrafast timescale are needed. Here, we use ultrafast optical pump-probe spectroscopy to reveal coexisting coupled magnetic orders in epitaxial TMO thin films grown on (001)-STO, which were not observed in previous work. Our temperature (T)-dependent transient differential reflectivity ({Delta}R/R) measurements show clear signatures of sinusoidal AFM, spiral AFM (FE) and FM phases developing as the film thickness changes. We carry out first-principle density functional theory (DFT) calculations to explain the coupling between AFM/FE and FM orders. These results reveal that the coupling between different magnetic orders observed in our multiferroic TMO thin films may offer greater control of functionality as compared to bulk single crystal multiferroics.

  13. Nuclear Physics: Recent Talks

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Free Electron Laser (FEL) Medical Imaging Physics Topics Campaigns Meetings Recent Talks Archived Talks Additional Information Computing at JLab Operations Logbook Physics Topics:...

  14. Nuclear Physics: Campaigns

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Free-Electron Laser (FEL) Medical Imaging Physics Topics Campaigns The Structure of the Nuclear Building Blocks The Structure of Nuclei Symmetry Tests in Nuclear Physics Meetings...

  15. B Physics: Theory Overview

    E-Print Network [OSTI]

    David London

    2012-07-23

    This is an overview of B physics that can be done at the LHC with the purpose of searching for new physics.

  16. Office of Physical Protection

    Broader source: Energy.gov [DOE]

    The Office of Physical Protection is comprised of a team of security specialists engaged in providing Headquarters-wide physical protection.

  17. Nuclear Physics: Experiment Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Research Highlights Public Interest Nuclear Physics Accelerator Free Electron Laser (FEL) Medical Imaging Physics Topics Campaigns Meetings Recent Talks Archived Talks...

  18. Evaluation of Physics Research

    E-Print Network [OSTI]

    Franssen, Michael

    ..........................................................................................23 Cluster: Physics of Transport in Fluids...................................................................................31 TU/e-9 Physics of Cold Atoms.....................................................................................................................................................................35 TU/e-10 Transport in Permeable Media

  19. Physics Advisory Committee Meeting

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2010 Physics Advisory Committee Meeting November 4-6, 2010 Comments and Recommendations Introduction The Fermilab Physics Advisory Committee (PAC) met to consider a number of...

  20. LANSCE Weapons Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    7 LANSCE Weapons Physics Fortune 500 companies and weapons designers alike rely on our internationally recognized nuclear physics and materials science expertise as well as our...

  1. ORISE: Health physics services

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Health physics services Nuclear power plant The Oak Ridge Institute for Science and Education (ORISE) offers comprehensive health physics services in a number of technical areas...

  2. ORISE: Health Physics Training

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Health Physics Training Student performs an analysis during an ORAU health physics training course Training and educating a highly skilled workforce that can meet operational...

  3. High Energy Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scientific Computing Research Basic Energy Sciences Biological and Environmental Research Fusion Energy Sciences High Energy Physics Nuclear Physics Advanced Scientific Computing...

  4. Molecular Gas in Elliptical Galaxies

    E-Print Network [OSTI]

    L. M. Young

    2000-09-05

    The distribution and kinematics of the molecular gas in elliptical galaxies give information on the origin and history of the gas and the rate of star formation activity in ellipticals. I describe some preliminary results of a survey which will more than double the number of elliptical galaxies with resolved molecular distributions.

  5. Molecular Motors: A Theorist's Perspective

    E-Print Network [OSTI]

    Molecular Motors: A Theorist's Perspective Anatoly B. Kolomeisky1 and Michael E. Fisher2 1/0505-0675$20.00 Key Words motor proteins, kinesin, myosin, single-molecule experiments, discrete stochastic models Abstract Individual molecular motors, or motor proteins, are enzymatic molecules that convert chemical

  6. Flat space physics from holography

    E-Print Network [OSTI]

    Bousso, Raphael

    2009-01-01

    thermodynamics in black hole physics. Phys. Rev. D 9, 3292 (LBNL-53861 Flat space physics from holography RaphaelBousso Center for Theoretical Physics, Department of Physics

  7. Aspects of Unparticle Physics

    E-Print Network [OSTI]

    Arvind Rajaraman

    2008-10-15

    We review some theoretical and experimental issues in unparticle physics, focusing mainly on collider signatures.

  8. particle physics 2009Highlights

    E-Print Network [OSTI]

    Report particle physics 2009ª #12;2 | Contents #12;Contents | 3 contentsª º introduction 4 º News;Introduction | 5 projects, (ii) coordination of national particle physics activities and (iii) reaching outparticle physics 2009ªHighlights and Annual Report Accelerators | Photon Science | Particle Physics

  9. Review of Particle Physics

    E-Print Network [OSTI]

    Nakamura, Kenzo

    2010-01-01

    careersvc/ • APS Careers in Physics: The American PhysicalAPS/DPF/DPB Summer Study on the Future of Particle Physics (APS Acta Physica Slovaca ARNPS Annual Review of Nuclear and Particle Science ARNS Annual Review of Nuclear Science ASP Astroparticle Physics

  10. Transition metal complex-based molecular machines 

    E-Print Network [OSTI]

    Sooksawat, Dhassida

    2015-06-30

    Inspired by the performance and evolutionarily-optimised natural molecular machines that carry out all the essential tasks contributing to the molecular basis of life, chemists aim towards fabricating synthetic molecular ...

  11. Fluctuations, Responses and Energetics of Molecular Motors

    E-Print Network [OSTI]

    Takahiro Harada; Shin-ichi Sasa

    2006-10-27

    A novel equality relating the rate of energy dissipation to a degree of violation of the fluctuation-response relation (FRR) in nonequilibrium Langevin systems is described. The FRR is a relation between the correlation function of the fluctuations and the response function of macroscopic variables. Although it has been established that the FRR holds in equilibrium, physical significance of violation of the FRR in nonequilibrium systems has been under debate. Recently, the authors have found that an extent of the FRR violation is related in a simple equality to the rate of energy dissipation into the environment in nonequilibrium Langevin systems. In this paper, we fully explain the FRR, the FRR violation, and the new equality with regard to a Langevin model termed a Brownian motor model, which is considered as a simple model of a biological molecular motor. Furthermore, applications of our result to experimental studies of molecular motors are discussed, and, as an illustration, we predict the value of a new time constant regarding the motion of a KIF1A, which is a kind of single-headed kinesin.

  12. Ice chemistry in starless molecular cores

    E-Print Network [OSTI]

    Kalvans, Juris

    2015-01-01

    Starless molecular cores are natural laboratories for interstellar molecular chemistry research. The chemistry of ices in such objects was investigated with a three-phase (gas, surface, and mantle) model. We considered the center part of five starless cores, with their physical conditions derived from observations. The ice chemistry of oxygen, nitrogen, sulfur, and complex organic molecules (COMs) was analyzed. We found that an ice-depth dimension, measured, e.g., in monolayers, is essential for modeling of chemistry in interstellar ices. Particularly, the H2O:CO:CO2:N2:NH3 ice abundance ratio regulates the production and destruction of minor species. It is suggested that photodesorption during core collapse period is responsible for high abundance of interstellar H2O2 and O2H, and other species synthesized on the surface. The calculated abundances of COMs in ice were compared to observed gas-phase values. Smaller activation barriers for CO and H2CO hydrogenation may help explain the production of a number of...

  13. Molecular Science Research Center annual report

    SciTech Connect (OSTI)

    Knotek, M.L.

    1991-01-01

    The Chemical Structure and Dynamics group is studying chemical kinetics and reactions dynamics of terrestrial and atmospheric processes as well as the chemistry of complex waste forms and waste storage media. Staff are using new laser systems and surface-mapping techniques in combination with molecular clusters that mimic adsorbate/surface interactions. The Macromolecular Structure and Dynamics group is determining biomolecular structure/function relationships for processes the control the biological transformation of contaminants and the health effects of toxic substances. The Materials and Interfaces program is generating information needed to design and synthesize advanced materials for the analysis and separation of mixed chemical waste, the long-term storage of concentrated hazardous materials, and the development of chemical sensors for environmental monitoring of various organic and inorganic species. The Theory, Modeling, and Simulation group is developing detailed molecular-level descriptions of the chemical, physical, and biological processes in natural and contaminated systems. Researchers are using the full spectrum of computational techniques. The Computer and Information Sciences group is developing new approaches to handle vast amounts of data and to perform calculations for complex natural systems. The EMSL will contain a high-performance computing facility, ancillary computing laboratories, and high-speed data acquisition systems for all major research instruments.

  14. Effect of carrier recombination on ultrafast carrier dynamics in thin films of the topological insulator Bi{sub 2}Se{sub 3}

    SciTech Connect (OSTI)

    Glinka, Yuri D.; Babakiray, Sercan; Johnson, Trent A.; Holcomb, Mikel B.; Lederman, David

    2014-10-27

    Transient reflectivity (TR) from thin films (6–40?nm thick) of the topological insulator Bi{sub 2}Se{sub 3} revealed ultrafast carrier dynamics, which suggest the existence of both radiative and non-radiative recombination between electrons residing in the upper cone of initially unoccupied high energy Dirac surface states (SS) and holes residing in the lower cone of occupied low energy Dirac SS. The modeling of measured TR traces allowed us to conclude that recombination is induced by the depletion of bulk electrons in films below ?20?nm thick due to the charge captured on the surface defects. We predict that such recombination processes can be observed using time-resolved photoluminescence techniques.

  15. High efficiency, high quality x-ray optic based on ellipsoidally bent highly oriented pyrolytic graphite crystal for ultrafast x-ray diffraction experiments

    SciTech Connect (OSTI)

    Uschmann, I.; Nothelle, U.; Foerster, E.; Arkadiev, V.; Langhoff, N.; Antonov, A.; Grigorieva, I.; Steinkopf, R.; Gebhardt, A

    2005-08-20

    By the use of a thin highly oriented pyrolytic graphite crystal (HOPG) bent to a high-performance ellipsoidal shape it was possible to focus monochromatic x-rays of 4.5 keV photon energy with an efficiency of 0.0033, which is 30 times larger than for previously used bent crystals. Isotropic TiK{sub a}lpha radiation of a 150 {mu}m source was focused onto a 450 {mu}m spot. The size of the focal spot can be explained by broadening due to the mosaic crystal rocking curve. The rocking curve width (FWHM) of the thin graphite foil was determined to 0.11 deg. . The estimated temporal broadening of an ultrashort Kalpha pulse by the crystal is not larger than 300 fs. These properties make the x-ray optic very attractive for ultrafast time-resolved x-ray measurements.

  16. Health Physics Technician | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Technician Department: ESH&S Staff: TSS04 Requisition Number: 1500441 Perform health physics support in the area of radiological assessment and implementation of radiation safety...

  17. Graduate Studies in Physics Ph.D. in Physics

    E-Print Network [OSTI]

    Graduate Studies in Physics Ph.D. in Physics M.Sc. in Physics (with thesis) M.Sc. in Physics (with major paper) M.Sc. in Physics (coursework only) www.uwindsor.ca/physics Research Facilities The Physics students an opportunity to be trained in developing new laboratory apparatus. Library resources for physics

  18. Protein Structure Suggests Role as Molecular Adapter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Role as Molecular Adapter Print To split and copy DNA during replication, all cellular organisms use a multicomponent molecular machine known as the replisome. An essential...

  19. Collective coordinates for nuclear spectral densities in energy transfer and femtosecond spectroscopy of molecular aggregates

    E-Print Network [OSTI]

    Mukamel, Shaul

    Collective coordinates for nuclear spectral densities in energy transfer and femtosecond collective nuclear coordinates necessary to represent a given set of spectral densities is obtained coordinates phase space. The signatures of excitonic and nuclear motions in ultrafast fluorescence

  20. Physics Division annual review, 1 April 1987--31 March 1988

    SciTech Connect (OSTI)

    Not Available

    1988-06-01

    This paper contains a description of the research project at Argonne National Laboratory over the past year (4/11/87--3/31/88). The major sections of this report in nuclear physics are: research at ATLAS; operation and development of TLAS: medium-energy nuclear physics and weak interactions; and theoretical nuclei physics. The major sections in atomic physics are: high-resolution laser-rf spectroscopy with beams of atoms, molecules and ions; beam-foil research, ion-beam laser interactions, and collision dynamics of heavy ions; interactions of fast atomic and molecular ions with solid and gaseous target; theoretical atomic physics; atomic physics at ATLAS; atomic physics using a synchrotron light source; and molecular structures and dynamics from coulomb-explosion measurements. (LSP)

  1. DOCTORAL PROGRAMME MATHEMATICS AND PHYSICS, Subprogramme PHYSICS,

    E-Print Network [OSTI]

    ?umer, Slobodan

    Safety Administration, Agency for Radioactive Waste Management and other organisations in the nuclear knowledge in energy conversion in nuclear power systems, design and operation of fission reactors, methods acquires a deeper knowledge of reactor physics and related nuclear physics basics. The student is trained

  2. Procedia PHYSICS 00 (2010) 14 Procedia Physics

    E-Print Network [OSTI]

    Adler, Joan

    2010-01-01

    Procedia PHYSICS 00 (2010) 1­4 Procedia Physics Visualization of nanodiamond formation in molten the characteristics and visualization of simulations of nanodiamond clusters grown from molten carbon. The general trends of nanodiamond size and quality as functions of growth conditions resemble those found

  3. PHYSICS 7397: NanoPhysics Spring 2010

    E-Print Network [OSTI]

    Peng, Haibing

    to Semiconductor Physics: Band structure, PN junction, Schottky barrier, and MOS structure. 2. Electron Transport) Physics of semiconductor devices / S.M. Sze and Kwok K. Ng. 3rd ed. Place/Publisher Hoboken, NJ : Wiley's responsibility to read and understand the Academic Honesty Policy found in the Student Handbook, which can

  4. Apparatus for molecular weight separation

    DOE Patents [OSTI]

    Smith, Richard D. (Richland, WA); Liu, Chuanliang (Haverhill, MA)

    2001-01-01

    The present invention relates generally to an apparatus and method for separating high molecular weight molecules from low molecular weight molecules. More specifically, the invention relates to the use of microdialysis for removal of the salt (low molecular weight molecules) from a nucleotide sample (high molecular weight molecules) for ESI-MS analysis. The dialysis or separation performance of the present invention is improved by (1) increasing dialysis temperature thereby increasing desalting efficiency and improving spectrum quality; (2) adding piperidine and imidazole to the dialysis buffer solution and reducing charge states and further increasing detection sensitivity for DNA; (3) using low concentrations (0-2.5 mM NH4OAc) of dialysis buffer and shifting the DNA negative ions to higher charge states, producing a nearly 10-fold increase in detection sensitivity and a slightly decreased desalting efficiency, (4) conducting a two-stage separation or (5) any combination of (1), (2), (3) and (4).

  5. Molecular biomechanics of collagen molecules

    E-Print Network [OSTI]

    Chang, Shu-Wei

    Collagenous tissues, made of collagen molecules, such as tendon and bone, are intriguing materials that have the ability to respond to mechanical forces by altering their structures from the molecular level up, and convert ...

  6. 11 August 2000 Z .Chemical Physics Letters 326 2000 110

    E-Print Network [OSTI]

    Apkarian, V. Ara

    11 August 2000 Z .Chemical Physics Letters 326 2000 1­10 www.elsevier.nlrlocatercplett Imaging-2025, USA Received 20 April 2000; in final form 7 June 2000 The memory of Kent R. Wilson, one of whose many-frequency plane. We illustrate this for the rovibronic coherence of molecular iodine in the gas phase. q 2000

  7. PAPER B3: PHYSICS OF FLUID FLOWS Hilary Term 2010

    E-Print Network [OSTI]

    Read, Peter L.

    systems · Industry ­ e.g. gases in pipes, polymer flows · Oil extraction ­ liquids flowing through: This defines a `local' . Similar for `local' temperature, velocity, etc. (NB: exclude gases at very low pressure.) [For molecular fluctuations, see Blundell and Blundell, Thermal Physics, p. 375, eq.(33.56): rms

  8. PHYSICS 122 LABORATORY (Winter, 2015)

    E-Print Network [OSTI]

    Yoo, S. J. Ben

    - 1 - PHYSICS 122 LABORATORY (Winter, 2015) COURSE GOALS 1. Learn how Tyson 514 Physics tyson@physics.ucdavis.edu 752-3830 Xiangdong Zhu 235 Physics zhu@physics.ucdavis.edu 752-4689 TEACHING ASSISTANTS: Andrew Bradshaw 518

  9. Molecular modeling of responsive polymer films

    SciTech Connect (OSTI)

    Tagliazucchi, Mario; Calvo, Ernesto J; Szleifer, Igal

    2010-06-29

    In this perspective, we have shown three different cases of responsive polymers at surfaces where the properties of the surface can be varied in response to cues from the bulk solution or in the presence of an external field. The most important conclusion in all three cases is that the chemical reaction equilibrium, physical interactions and molecular organization are strongly coupled, and it is imperative to consider the global and local changes that occur to the surface structure and properties due to this coupling. In particular acid-base and redox equilibrium are very different in polymer-modified surfaces than in the corresponding bulk solutions. Moreover, the definition of ‘‘apparent redox potentials’’ and ‘‘apparent pKa’’results from the averaging over highly inhomogeneous values,and, therefore, they do not necessarily represent the state of the layer and the local values and their variation are very important for the design of functional surfaces. The very large variation on chemical equilibrium results from the optimization of all the interactions. The picture that emerges is that trying to deduce what the final state of the system is by looking at the individual optimization of each contribution leads to qualitative incorrect assumptions and only the minimization of the complete free energy leads to the proper behavior in these complex systems.In the cases where domain formation is possible in grafted weak polyacid layers charge regulation may lead to regimes of coexistence between aggregates with relatively low fraction of charged polymer segments surrounded by highly stretched chains that have a relatively high fraction of charged groups.Therefore, one can control the state of charge, local electrostatic potential and local pH in all three dimensions with im-portant gradients on length scales of nanometers. For hydrophobic redox polymers we show how the application of an electrode potential can lead to changes in the structure and type of morphological aggregates that can form on the surface.Again, these structures result from the optimization of chemical redox equilibrium, conformational entropy, electrostatic and hydrophobic interactions. Furthermore, changes in domains structure can manifest themselves in the capacitance-potential curves and then provide a link between macroscopic measurements and the formation of nanoscopic domains. It is clear that chemical engineers are in a unique position to use these switchable surfaces in the molecular design of sensors, biosensors, separation devices, microfluidic devices with on-off environmental switches and drug delivery systems among many others. Finally, we want to stress that the application of molecular theories, where the coupling between chemical equilibrium, physical interactions and molecular organization are explicitly included provide with quantitative predictions of the layers properties, as compared with experimental observations, and enable the fundamental understanding of the observed behavior. Moreover, the theory provides with a detailed microscopic picture and should be used as an integral part in the design of functional and responsive surfaces. It is important to emphasize that the molecular approaches are not exact, and, therefore, there is a need to continue their development and the incorporation of improved approximations to further broaden their applicability.

  10. 2010 Atomic & Molecular Interactions Gordon Research Conference

    SciTech Connect (OSTI)

    Todd Martinez

    2010-07-23

    The Atomic and Molecular Interactions Gordon Conferences is justifiably recognized for its broad scope, touching on areas ranging from fundamental gas phase and gas-condensed matter collision dynamics, to laser-molecule interactions, photophysics, and unimolecular decay processes. The meeting has traditionally involved scientists engaged in fundamental research in gas and condensed phases and those who apply these concepts to systems of practical chemical and physical interest. A key tradition in this meeting is the strong mixing of theory and experiment throughout. The program for 2010 conference continues these traditions. At the 2010 AMI GRC, there will be talks in 5 broadly defined and partially overlapping areas of intermolecular interactions and chemical dynamics: (1) Photoionization and Photoelectron Dynamics; (2) Quantum Control and Molecules in Strong Fields; (3) Photochemical Dynamics; (4) Complex Molecules and Condensed Phases; and (5) Clusters and Reaction Dynamics. These areas encompass many of the most productive and exciting areas of chemical physics, including both reactive and nonreactive processes, intermolecular and intramolecular energy transfer, and photodissociation and unimolecular processes. Gas phase dynamics, van der Waals and cluster studies, laser-matter interactions and multiple potential energy surface phenomena will all be discussed.

  11. Examples of molecular self-assembly at surfaces

    E-Print Network [OSTI]

    Stephen Whitelam

    2014-12-05

    The self-assembly of molecules at surfaces can be caused by a range of physical mechanisms. Assembly can be driven by intermolecular forces, or molecule-surface forces, or both; it can result in structures that are in equilibrium or that are kinetically trapped. Here we review examples of self-assembly at surfaces that have been studied within the User program of the Molecular Foundry at Lawrence Berkeley National Laboratory, focusing on a physical understanding of what causes patterns seen in experiment. Some apparently disparate systems can be described in similar physical terms, indicating that simple factors -- such as the geometry and energy scale of intermolecular binding -- are key to understanding the self-assembly of those systems.

  12. Chemical Dynamics, Molecular Energetics, and Kinetics at the Synchrotron

    SciTech Connect (OSTI)

    Leone, Stephen R.; Ahmed, Musahid; Wilson, Kevin R.

    2010-03-14

    Scientists at the Chemical Dynamics Beamline of the Advanced Light Source in Berkeley are continuously reinventing synchrotron investigations of physical chemistry and chemical physics with vacuum ultraviolet light. One of the unique aspects of a synchrotron for chemical physics research is the widely tunable vacuum ultraviolet light that permits threshold ionization of large molecules with minimal fragmentation. This provides novel opportunities to assess molecular energetics and reaction mechanisms, even beyond simple gas phase molecules. In this perspective, significant new directions utilizing the capabilities at the Chemical Dynamics Beamline are presented, along with an outlook for future synchrotron and free electron laser science in chemical dynamics. Among the established and emerging fields of investigations are cluster and biological molecule spectroscopy and structure, combustion flame chemistry mechanisms, radical kinetics and product isomer dynamics, aerosol heterogeneous chemistry, planetary and interstellar chemistry, and secondary neutral ion-beam desorption imaging of biological matter and materials chemistry.

  13. Ultrafast neutron detector

    DOE Patents [OSTI]

    Wang, Ching L. (Livermore, CA)

    1987-01-01

    The invention comprises a neutron detector (50) of very high temporal resolution that is particularly well suited for measuring the fusion reaction neutrons produced by laser-driven inertial confinement fusion targets. The detector comprises a biased two-conductor traveling-wave transmission line (54, 56, 58, 68) having a uranium cathode (60) and a phosphor anode (62) as respective parts of the two conductors. A charge line and Auston switch assembly (70, 72, 74) launch an electric field pulse along the transmission line. Neutrons striking the uranium cathode at a location where the field pulse is passing, are enabled to strike the phosphor anode and produce light that is recorded on photographic film (64). The transmission line may be variously configured to achieve specific experimental goals.

  14. Ultrafast neutron detector

    DOE Patents [OSTI]

    Wang, C.L.

    1985-06-19

    A neutron detector of very high temporal resolution is described. It may be used to measure distributions of neutrons produced by fusion reactions that persist for times as short as about 50 picoseconds.

  15. Princeton Plasma Physics Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Plasma Physics Laboratory P.O. Box 451 Princeton, NJ 08543-0451 GPS: 100 Stellarator Road Princeton, NJ 08540 www.pppl.gov 2015 Princeton Plasma Physics Laboratory. A...

  16. Probing new physics with flavor physics (and probing flavor physics with new physics)

    E-Print Network [OSTI]

    Yosef Nir

    2007-08-14

    This is a written version of a series of lectures aimed at graduate students and postdoctoral fellows in particle theory/string theory/particle experiment familiar with the basics of the Standard Model. We begin with an overview of flavor physics and its implications for new physics. We emphasize the "new physics flavor puzzle". Then, we give four specific examples of flavor measurements and the lessons that have been (or can be) drawn from them: (i) Charm physics: lessons for supersymmetry from the upper bound on $\\Delta m_D$. (ii) Bottom physics: model independent lessons on the KM mechanism and on new physics in neutral B mixing from $S_{\\psi K_S}$. (iii) Top physics and beyond: testing minimal flavor violation at the LHC. (iv) Neutrino physics: interpreting the data on neutrino masses and mixing within flavor models.

  17. Review of Higgs physics

    E-Print Network [OSTI]

    Ocariz, Jose; The ATLAS collaboration

    2015-01-01

    The eperimental status on Higgs boson physics is reviewed. Results from both ATLAS and CMS, using data collected in LHC run 1, are presented. Prospects for Higgs physics with Run 2 and beyond are discussed.

  18. Future Physics | Jefferson Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Future Physics March 5, 2009 In late January, we held a meeting of our Physics Advisory Committee, PAC34 to be precise. We had two primary goals for the PAC, one related to the...

  19. Physics and Consciousness

    E-Print Network [OSTI]

    Patricio Perez

    1995-10-17

    Some contributions of physics towards the understanding of consciousness are described. As recent relevant models, associative memory neural networks are mentioned. It is shown that consciousness and quantum physics share some properties. Two existing quantum models are discussed.

  20. Polymer Physics Research Profile

    E-Print Network [OSTI]

    Giger, Christine

    Polymer Physics Research Profile Our main interests are the theory of simplification and some behavior on different autonomous levels of description. Our favorite applications range from polymer + Nonequilibrium Thermodynamics + Coarse Graining + Soft Matter + Polymer Physics + Rheology + Competences

  1. PHYSICS 660: Homework 1

    E-Print Network [OSTI]

    2015-09-24

    PHYSICS 660: Homework 1. Yingwei Wang ?. Department of Mathematics, Purdue University, West Lafayette, IN, USA. 1 Modified Schrödinger equation.

  2. Center for Beam Physics

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2010-01-01

    Krishnagopal of CAT, Indore, India, we are also developing aon Beam Physics at CAT, Indore, India and Telecourse on Beam

  3. How to Popularize Physics

    ScienceCinema (OSTI)

    Simmons, Elizabeth [Michigan State University, East Landing, Michigan, United States

    2009-09-01

    This talk discusses the whys and hows of educational outreach and presents examples from several fields of physics.

  4. Particle Physics and Cosmology

    E-Print Network [OSTI]

    Edward W. Kolb

    1994-03-03

    Lectures presented at the 42nd Scottish Universities Summer School in Physics, St. Andrews, Scotland, August 1993.

  5. Time Asymmetric Quantum Physics

    E-Print Network [OSTI]

    A. Bohm

    1999-02-26

    Mathematical and phenomenological arguments in favor of asymmetric time evolution of micro-physical states are presented.

  6. Quantum Physics Einstein's Gravity

    E-Print Network [OSTI]

    Visser, Matt

    Quantum Physics confronts Einstein's Gravity Matt Visser Physics Department Washington University Saint Louis USA Science Saturdays 13 October 2001 #12; Quantum Physics confronts Einstein's Gravity and with Einstein's theory of gravity (the general relativity) is still the single biggest theoretical problem

  7. Whither Nuclear Physics ?

    E-Print Network [OSTI]

    Syed Afsar Abbas

    2008-01-07

    Nuclear Physics has had its ups and downs. However in recent years, bucked up by some new and often puzzling data, it has become a potentially very rich field. We review some of these exciting developments in a few important sectors of nuclear physics. Emphasis shall be on the study of exotic nuclei and the new physics that these nuclei are teaching us.

  8. Physics & Astronomy Scholarships

    E-Print Network [OSTI]

    Almor, Amit

    Physics & Astronomy Scholarships Complete Scholarship Name Application Deadline Date Contact Name senior undergraduate physics majors. The final selection of the recipient shall be made as follows award. No N/A Evelyn Wong 803.777.8105 wonge@sc.edu Special Physics Research Fellowship The candidate

  9. B Physics at LHCb

    E-Print Network [OSTI]

    Monica Pepe Altarelli; Frederic Teubert

    2008-04-07

    LHCb is a dedicated detector for b physics at the LHC. In this article we present a concise review of the detector design and performance together with the main physics goals and their relevance for a precise test of the Standard Model and search of New Physics beyond it.

  10. Physical Algorithms Roger Wattenhofer

    E-Print Network [OSTI]

    Physical Algorithms Roger Wattenhofer Computer Engineering and Networks Laboratory TIK ETH Zurich to an ICALP 2010 invited talk, intending to encourage research in physical algorithms. The area of physical algorithms deals with networked systems of active agents. These agents have access to limited information

  11. m anchester particle physics

    E-Print Network [OSTI]

    . The stochastic nature of high energy physics data often gives rise to unwelcome statistical fluctuations; our energy physics data analysis systems, HBOOK [1] and PAW [2]. Submitted To Computer Physics Communications are usually sparse because the interaction cross­sections are so small; even theory produces sparse and random

  12. COURSE OUTLINE Physics 777

    E-Print Network [OSTI]

    : An introduction to plasma physics and magnetohydrodynamics for advanced graduate students. Applications to Solar, Holland Frances F. Chen Introduction to Plasma Physics 1984, Plenum, New York Week 1: Review of Solar Physics Priest Chapter 1 Week 2: Introduction Chen Chapters 1, 2 and 7 --Plasma Parameters --Single

  13. REVIEW OF PARTICLE PHYSICS

    E-Print Network [OSTI]

    Beringer, Juerg

    2013-01-01

    APS Careers: gateway for physicists, students, and physicsAPS/DPF/DPB Summer Study on the Future of Particle Physics (APS Acta Physica Slovaca ARNPS Annual Review of Nuclear and Particle Science ARNS Annual Review of Nuclear Science ASP Astroparticle Physics

  14. Heteropolymer freezing and design: Towards physical models of protein folding

    SciTech Connect (OSTI)

    Pande, Vijay S. [Chemistry Department, Stanford University, Stanford, California 94305-5080 (United States)] [Chemistry Department, Stanford University, Stanford, California 94305-5080 (United States); Grosberg, Alexander Yu. [Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States)] [Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Tanaka, Toyoichi [Department of Physics and Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Department of Physics and Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2000-01-01

    Protein folding has become one of the most actively studied problems in modern molecular biophysics. Approaches to the problem combine ideas from the physics of disordered systems, polymer physics, and molecular biology. Much can be learned from the statistical properties of model heteropolymers, the chain molecules having different monomers in irregular sequences. Even in highly evolved proteins, there is a strong random element in the sequences, which gives rise to a statistical ensemble of sequences for a given folded shape. Simple analytic models give rise to phase transitions between random, glassy, and folded states, depending on the temperature T and the design temperature T{sup des} of the ensemble of sequences. Besides considering the analytic results obtainable in a random-energy model and in the Flory mean-field model of polymers, the article reports on confirming numerical simulations. (c) 2000 The American Physical Society.

  15. Final Report: High Energy Physics Program (HEP), Physics Department...

    Office of Scientific and Technical Information (OSTI)

    Final Report: High Energy Physics Program (HEP), Physics Department, Princeton University Citation Details In-Document Search Title: Final Report: High Energy Physics Program...

  16. Luu, T; Platter, L 73 NUCLEAR PHYSICS AND RADIATION PHYSICS;...

    Office of Scientific and Technical Information (OSTI)

    constraints from Big Bang nucleosynthesis Bedaque, P; Luu, T; Platter, L 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; DEUTERIUM; FIELD THEORIES; NUCLEAR PHYSICS; NUCLEOSYNTHESIS;...

  17. DEPARTMENT OF PHYSICS General Syllabus

    E-Print Network [OSTI]

    Brinkmann, Peter

    DEPARTMENT OF PHYSICS General Syllabus Physics 45300 Physical Photonics I/Laser Optics Designation: Elective Undergraduate Catalog description: Theory and applications of lasers and masers. Physical: Pre- or coreq.: a course in modern physics (Physics 55100 or Physics 32100), a course in electricity

  18. Ab-Initio Molecular Dynamics

    E-Print Network [OSTI]

    Thomas D. Kühne

    2013-03-26

    Computer simulation methods, such as Monte Carlo or Molecular Dynamics, are very powerful computational techniques that provide detailed and essentially exact information on classical many-body problems. With the advent of ab-initio molecular dynamics, where the forces are computed on-the-fly by accurate electronic structure calculations, the scope of either method has been greatly extended. This new approach, which unifies Newton's and Schr\\"odinger's equations, allows for complex simulations without relying on any adjustable parameter. This review is intended to outline the basic principles as well as a survey of the field. Beginning with the derivation of Born-Oppenheimer molecular dynamics, the Car-Parrinello method and the recently devised efficient and accurate Car-Parrinello-like approach to Born-Oppenheimer molecular dynamics, which unifies best of both schemes are discussed. The predictive power of this novel second-generation Car-Parrinello approach is demonstrated by a series of applications ranging from liquid metals, to semiconductors and water. This development allows for ab-initio molecular dynamics simulations on much larger length and time scales than previously thought feasible.

  19. Physics of Primordial Universe

    E-Print Network [OSTI]

    Maxim Yu. Khlopov

    2003-09-25

    The physical basis of the modern cosmological inflationary models with baryosynthesis and nonbaryonic dark matter and energy implies such predictions of particle theory, that, in turn, apply to cosmology for their test. It makes physics of early Universe ambiguous and particle model dependent. The study of modern cosmology is inevitably linked with the probe for the new physics, underlying it. The particle model dependent phenomena, such as unstable dark matter, primordial black holes, strong primordial inhomogeneities, can play important role in revealing the true physical cosmology. Such phenomena, having serious physical grounds and leading to new nontrivial cosmological scenarious, should be taken into account in the data analysis of observational cosmology.

  20. A Quantitative Analysis of IRAS Maps of Molecular Clouds

    E-Print Network [OSTI]

    Jennifer J. Wiseman; Fred C. Adams

    1994-04-20

    We present an analysis of IRAS maps of five molecular clouds: Orion, Ophiuchus, Perseus, Taurus, and Lupus. For the classification and description of these astrophysical maps, we use a newly developed technique which considers all maps of a given type to be elements of a pseudometric space. For each physical characteristic of interest, this formal system assigns a distance function (a pseudometric) to the space of all maps; this procedure allows us to measure quantitatively the difference between any two maps and to order the space of all maps. We thus obtain a quantitative classification scheme for molecular clouds. In this present study we use the IRAS continuum maps at 100$\\mu$m and 60$\\mu$m to produce column density (or optical depth) maps for the five molecular cloud regions given above. For this sample of clouds, we compute the ``output'' functions which measure the distribution of density, the distribution of topological components, the self-gravity, and the filamentary nature of the clouds. The results of this work provide a quantitative description of the structure in these molecular cloud regions. We then order the clouds according to the overall environmental ``complexity'' of these star forming regions. Finally, we compare our results with the observed populations of young stellar objects in these clouds and discuss the possible environmental effects on the star formation process. Our results are consistent with the recently stated conjecture that more massive stars tend to form in more ``complex'' environments.

  1. Transverse Spin Physics: Recent Developments

    E-Print Network [OSTI]

    Yuan, Feng

    2009-01-01

    that the transverse spin physics is playing a very importantrole in the strong interaction physics forhadronic spin physics. We will learn more about QCD dynamics

  2. Primordial nucleosynthesis and neutrino physics

    E-Print Network [OSTI]

    Smith, Christel Johanna

    2009-01-01

    A Brief History of and Introduction to Neutrino Physics . 13Theoretical Nuclear Physics, Volume I: Nuclear Structure, 1McGregor, in Particle Physics and Cosmology: Third Tropical

  3. Ab-Initio Molecular Dynamics

    E-Print Network [OSTI]

    Kühne, Thomas D

    2012-01-01

    Computer simulations and molecular dynamics in particular, is a very powerful method to provide detailed and essentially exact informations of classical many-body problems. With the advent of \\textit{ab-initio} molecular dynamics, where the forces are computed on-the-fly by accurate electronic structure calculations, the scope of either method has been greatly extended. This new approach, which unifies Newton's and Schr\\"odinger's equations, allows for complex simulations without relying on any adjustable parameter. This review is intended to outline the basic principles as well as a survey of the field. Beginning with the derivation of Born-Oppenheimer molecular dynamics, the Car-Parrinello method as well as novel hybrid scheme that unifies best of either approach are discussed. The predictive power is demonstrated by a series of applications ranging from insulators to semiconductors and even metals in condensed phases.

  4. Bright, Coherent, Ultrafast Soft X-Ray Harmonics Spanning the Water Window from a Tabletop Light Source

    E-Print Network [OSTI]

    M. C. Chen; P. Arpin; T. Popmintchev; M. Gerrity; B. Zhang; M. Seaberg; M. M. Murnane; H. C. Kapteyn

    2010-06-20

    We demonstrate fully phase matched high-order harmonic generation with emission spanning the water window spectral region important for bio- and nano-imaging and a breadth of materials and molecular dynamics studies. We also generate the broadest bright coherent bandwidth (~300eV) to date obtained from any light source, small or large. The harmonic photon flux at 0.5 keV is 10^3 higher than demonstrated previously, making it possible for the first time to demonstrate spatial coherence in the water window. The continuum emission is consistent with a single attosecond burst, that extends bright attosecond pulses into the soft x-ray region.

  5. Imaging Arithmetic: Physics Math > Physics + Math Gaurav Sharma

    E-Print Network [OSTI]

    Sharma, Gaurav

    Imaging Arithmetic: Physics Math > Physics + Math Gaurav Sharma Electrical and Computer, NY 14627-0126 ABSTRACT Imaging devices operate at the physical interfaces corresponding to image capture and reproduction. The combi- nation of physical insight and mathematical signal processing tools

  6. sCieNCe aND on the nanoscale (~10-9 meters) concepts of physics,

    E-Print Network [OSTI]

    Svenningsson, Josef

    influence, or even determine, the behaviour of electronic, optical, superconducting, and molecular devices- and Nano-fabrication (7,5p) Quantum Engineering (7,5p) Superconductivity and low- temperature physics (7,5p

  7. THE JOURNAL OF CHEMICAL PHYSICS 135, 104303 (2011) The visible spectrum of zirconium dioxide, ZrO2

    E-Print Network [OSTI]

    Maier, John Paul

    2011-01-01

    THE JOURNAL OF CHEMICAL PHYSICS 135, 104303 (2011) The visible spectrum of zirconium dioxide, ZrO2; published online 8 September 2011) The electronic spectrum of a cold molecular beam of zirconium dioxide, Zr

  8. MOLECULAR ENTOMOLOGY Molecular Identification Key for Pest Species of Scirtothrips

    E-Print Network [OSTI]

    Hoddle, Mark S.

    primers and determining the size of the products by using standard agarose gel electrophoresis, followed, Neohydatothrips, molecular identiÞcation key, exotic pests, nondestruc- tive DNA extraction The genus Scirtothrips, several species of Scirtothrips have (or have the potential to) spread from their natural habitats

  9. Large-Scale Molecular Dynamics Simulations for Highly Parallel Infrastructures

    E-Print Network [OSTI]

    Pazúriková, Jana

    2014-01-01

    Computational chemistry allows researchers to experiment in sillico: by running a computer simulations of a biological or chemical processes of interest. Molecular dynamics with molecular mechanics model of interactions simulates N-body problem of atoms$-$it computes movements of atoms according to Newtonian physics and empirical descriptions of atomic electrostatic interactions. These simulations require high performance computing resources, as evaluations within each step are computationally demanding and billions of steps are needed to reach interesting timescales. Current methods decompose the spatial domain of the problem and calculate on parallel/distributed infrastructures. Even the methods with the highest strong scaling hit the limit at half a million cores: they are not able to cut the time to result if provided with more processors. At the dawn of exascale computing with massively parallel computational resources, we want to increase the level of parallelism by incorporating parallel-in-time comput...

  10. Physics Physics Annual Review, 1 April 1981-31 March 1982

    SciTech Connect (OSTI)

    Not Available

    1982-12-01

    In medium-energy pion physics, considerable progress has been made in understanding the propagation and absorption of pions (deltas) in the nuclear medium. An experiment to study neutrino oscillations is being planned at LAMPF with substantial involvement from Argonne. A major effort is being devoted to the scientific and technical considerations involved in proposing to build a multi-GeV C.W. electron accelerator: GEM at Argonne. In heavy-ion physics, the superconducting linac booster is being used with increasing scientific profit. Construction of the ATLAS facility began in FY 1982 and all progress has been on schedule. The importance of the time component of the weak axial-vector current has been studied through the ..beta.. decay of /sup 16/N. A precision measurement is under way of the /sup 7/Be(p,..gamma..) cross section, one of the key components in the solar neutrino anomaly. In nuclear theory, the coupled-channel code for treating heavy-ion inelastic scattering was completed and application to particular experiments began. Nuclear structure theory was applied to interpret decays of high-spin states and inelastic pion scattering. Results of particular interest were obtained in the nuclear force program where the inclusion of 3-body forces led to simultaneous improvement in the binding of /sup 3/He and /sup 4/He and saturation of nuclear matter. The atomic physics research consists of six experimental programs as follows: (1) dissociation and other interactions of energetic molecular ions in solid and gaseous targets; (2) electron spectroscopy with fast atomic and molecular-ion beams; (3) beam-foil research and collision dynamics of heavy ions; (4) photoionization-photoelectron research; (5) high-resolution, laser-rf spectroscopy with atomic and molecular beams; and (6) theoretical atomic physics. (WHK)

  11. The encyclopedia of physics. Third edition

    SciTech Connect (OSTI)

    Bescancon, R.M.

    1985-01-01

    This encyclopedia contains 350 articles which have been selected to give adequate representation to all branches of the subject, with emphasis on new and sophisticated concepts. A special feature of this encyclopedia is its arrangement of material. Articles on the main divisions of physics are written for readers with little background in the subject, articles on subdivisions are aimed at those with more knowledge, and articles on finer division are geared to users with farily sound backgrounds in physics and mathematics. Among the topics given new or expanded coverage are gauge theories, quantum chromodynamics, electroweak theory, and grand unified theories. Readers will also find new information on particle theory, biomedical instrumentation, molecular biology, quarks and pulsars, laser fusion, and volcanology.

  12. Focus on the Physics of Cancer

    E-Print Network [OSTI]

    Risler, Thomas

    2015-01-01

    Despite the spectacular achievements of molecular biology in the second half of the twentieth century and the crucial advances it permitted in cancer research, the fight against cancer has brought some disillusions. It is nowadays more and more apparent that getting a global picture of the very diverse and interlinked aspects of cancer development necessitates, in synergy with these achievements, other perspectives and investigating tools. In this undertaking, multidisciplinary approaches that include quantitative sciences in general and physics in particular play a crucial role. This `focus on' collection contains 19 articles representative of the diversity and state-of-the-art of the contributions that physics can bring to the field of cancer research.

  13. The Intersection of Physics and Biology

    ScienceCinema (OSTI)

    Liphardt, Jan [University of California, Berkeley, California, United States

    2010-09-01

    In April 1953, Watson and Crick largely defined the program of 20th century biology: obtaining the blueprint of life encoded in the DNA. Fifty years later, in 2003, the sequencing of the human genome was completed. Like any major scientific breakthrough, the sequencing of the human genome raised many more questions than it answered. I'll brief you on some of the big open problems in cell and developmental biology, and I'll explain why approaches, tools, and ideas from the physical sciences are currently reshaping biological research. Super-resolution light microscopies are revealing the intricate spatial organization of cells, single-molecule methods show how molecular machines function, and new probes are clarifying the role of mechanical forces in cell and tissue function. At the same time, Physics stands to gain beautiful new problems in soft condensed matter, quantum mechanics, and non-equilibrium thermodynamics.

  14. THE PHYSICS MAJOR (Physics and Astronomy & Astrophysics Streams)

    E-Print Network [OSTI]

    Tobar, Michael

    THE PHYSICS MAJOR (Physics and Astronomy & Astrophysics Streams) Overview: Physics examines, to the behaviour of matter on the subatomic scale - and everything in between. Studying Physics at UWA gives you access to the frontiers of modern physics, built on the pillars of quantum physics and relativity. You

  15. INTRODUCTION TO PHYSICS 107 INTRODUCTORY APPLIED PHYSICS LAB: MECHANICS

    E-Print Network [OSTI]

    Hart, Gus

    i INTRODUCTION TO PHYSICS 107 INTRODUCTORY APPLIED PHYSICS LAB: MECHANICS AND THERMODYNAMICS What do we do in Physics 107? Physics 107 is a lab designed to support the Physics 105 lecture. Hopefully. In addition it will give you a more physical experience with the material, skills in measuring and analyzing

  16. Physics 151 Lecture 1 Physics 207: Lecture 1, Pg 1

    E-Print Network [OSTI]

    Winokur, Michael

    Page 1 Physics 151 ­ Lecture 1 Physics 207: Lecture 1, Pg 1 Physics 207, Sections: 301/601Physics 207, Sections: 301/601 ­­ 314/614314/614 General Physics IGeneral Physics I MichaelMichael WinokurWinokur & Pupa Gilbert& Pupa Gilbert Lecture 1Lecture 1 Agenda for TodayAgenda for Today Course Introduction

  17. of PhysicsTuesday, March 29, 2005 of Physics 2005

    E-Print Network [OSTI]

    Auzinsh, Marcis

    University of Latvia Department of PhysicsTuesday, March 29, 2005 - 1 - World Year of Physics 2005 #12;University of Latvia Department of PhysicsTuesday, March 29, 2005 - 2 - World Year of Physics 2005 Latvia #12;University of Latvia Department of PhysicsTuesday, March 29, 2005 - 3 - World Year of Physics

  18. of PhysicsTuesday, March 08, 2005 of Physics 2005

    E-Print Network [OSTI]

    Auzinsh, Marcis

    University of Latvia Department of PhysicsTuesday, March 08, 2005 - 1 - World Year of Physics 2005 of Latvia Department of PhysicsTuesday, March 08, 2005 - 2 - World Year of Physics 2005 Latvia #12;University of Latvia Department of PhysicsTuesday, March 08, 2005 - 3 - World Year of Physics 2005 University

  19. THE JOURNAL OF CHEMICAL PHYSICS 139, 244108 (2013) Periodic boundary conditions for QM/MM calculations: Ewald summation

    E-Print Network [OSTI]

    Herbert, John

    2013-01-01

    THE JOURNAL OF CHEMICAL PHYSICS 139, 244108 (2013) Periodic boundary conditions for QM/MM of Ewald summation for use in mixed quantum mechanics/molecular mechanics (QM/MM) calculations is presented a method for applying PBC to mixed quantum mechanics/molecular mechanics (QM/MM) simula- tions. We

  20. GRADUATE STUDENT Department of Physics

    E-Print Network [OSTI]

    Zallen, Richard

    General Policies and Procedures The Physics department offers M.S. and Ph.D. degrees in physicsGRADUATE STUDENT HANDBOOK Department of Physics Virginia Polytechnic Institute and State University November 2014 #12;2 _________________________________________________________________ Virginia Tech Physics

  1. Engineering Physics University of Saskatchewan

    E-Print Network [OSTI]

    Saskatchewan, University of

    Engineering Physics at the University of Saskatchewan Professor Adam Bouras adam.bourassa@usask. #12;What is Engineering Physics? A bridge between engineering and pure science Physics + Engineering + Mathematics Fundamental physics and math combined with engineering and problem solving analytical

  2. Physically Observable Cryptography Silvio Micali

    E-Print Network [OSTI]

    Reyzin, Leonid

    Physically Observable Cryptography Silvio Micali Leonid Reyzin November 29, 2003 Abstract.) inherent in the physical execution of any cryptographic algorithm. Such "physical observation attacks mathematically impregnable systems. The great practicality and the inherent availability of physical attacks

  3. Electron-nuclear correlations for photo-induced dynamics in molecular dimers

    E-Print Network [OSTI]

    of the nuclear equilibrium upon photoexcitation. In the limiting case of resonance between the electronic energy with the overall nuclear wave packet width. The demonstrated quantum relaxation features of the photoinduced dynamics in molecular systems, which play domi- nant roles in a variety of problems in physics, technology

  4. Light Quasiparticles Dominate Electronic Transport in Molecular Crystal Field-Effect Transistors

    E-Print Network [OSTI]

    Light Quasiparticles Dominate Electronic Transport in Molecular Crystal Field-Effect Transistors Z 1 Department of Physics, University of California, San Diego, La Jolla, California 92093, USA 2, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA (Received 1 March 2007; published 6

  5. Physics Topics - MST - UW Plasma Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid youOxygen Generation | Center for GasPhysics Physics Print Because

  6. Molecular Foundry, Berkeley, California (Revised)

    SciTech Connect (OSTI)

    Carlisle, N.

    2008-03-01

    This case study provides information on the Molecular Foundry, which incorporates Labs21 principles in its design and construction. The design includes many of the strategies researched at Lawrence Berkeley Laboratory for energy efficient cleanroom and data centers. The result is an energy efficient high-performing sustainable laboratory.

  7. 3. Advanced Polymer Molecular Science

    E-Print Network [OSTI]

    Duh, Kevin

    Development to Realize New Energy and Electrical Equipment Advanced Functional Materials 100 nm (PEN and Electrons Surface and Materials Science 1. New Photo-Functional Materials Using Quantum Effects Quantum Analysis System and Molecular Imagining Sensory Materials and Devices 1 mm #12;26. New Material

  8. Ethanoltank TurboMolecularPump

    E-Print Network [OSTI]

    Maruyama, Shigeo

    CCVD at low pressure (less than 0.1 Pa). The advanced generation method based on the SWNT growthEthanoltank Oil pump TurboMolecularPump Ion gauge Leak valve Silicon heater Scroll pump Gate valve. Shiokawa et al. [2] have reported that SWNTs can be grown at low temperature for nanodevices by performing

  9. Nuclear Halo and Molecular States

    E-Print Network [OSTI]

    N. A. Orr

    2000-11-02

    Significant advances have been made in recent years in the exploration of clustering in light nuclei. This progress has arisen not only from the investigation of new systems, but also through the development and application of novel probes. This paper will briefly review selected topics concerning halo and molecular states in light nuclei through examples provided by the neutron-rich Be isotopes.

  10. 3. Advanced Polymer Molecular Science

    E-Print Network [OSTI]

    Duh, Kevin

    3. Advanced Polymer Molecular Science Advanced Polymer Science 4. Photo-Functional Elements at the Center of Advanced Technology Photonic Device Science 5. Research on Functional Information Elements supporting the Next-generation Information Society Information Device Science EL 6. Energy Electronic

  11. Modern concepts in molecular modeling

    SciTech Connect (OSTI)

    Bajorath, J.; Klein, T.E.

    1996-12-31

    This session focused on the application of computer models and the development and application of various energy functions to study the structure, energetics and dynamics of proteins and their interactions with ligands. These studies provide an exciting view of current developments in computer-aided molecular modeling and theoretical analysis of biological molecules.

  12. Experimental Mathematics and Mathematical Physics

    E-Print Network [OSTI]

    Bailey, David H.

    2009-01-01

    Journal of Physics A: Mathematics and General, vol. 41 (Journal of Physics A: Mathematics and General, vol. 39 [9

  13. Nuclear & Particle Physics, Astrophysics, Cosmology

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nuclear & Particle Physics science-innovationassetsimagesicon-science.jpg Nuclear & Particle Physics, Astrophysics, Cosmology National security depends on science and...

  14. Symmetries in physics

    E-Print Network [OSTI]

    Roelof Bijker

    2005-09-02

    The concept of symmetries in physics is briefly reviewed. In the first part of these lecture notes, some of the basic mathematical tools needed for the understanding of symmetries in nature are presented, namely group theory, Lie groups and Lie algebras, and Noether's theorem. In the second part, some applications of symmetries in physics are discussed, ranging from isospin and flavor symmetry to more recent developments involving the interacting boson model and its extension to supersymmetries in nuclear physics.

  15. Optical laser systems at the Linac Coherent Light Source

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Minitti, Michael P.; Robinson, Joseph S.; Coffee, Ryan N.; Edstrom, Steve; Gilevich, Sasha; Glownia, James M.; Granados, Eduardo; Hering, Philippe; Hoffmann, Matthias C.; Miahnahri, Alan; et al

    2015-04-22

    Ultrafast optical lasers play an essential role in exploiting the unique capabilities of recently commissioned X-ray free-electron laser facilities such as the Linac Coherent Light Source (LCLS). Pump–probe experimental techniques reveal ultrafast dynamics in atomic and molecular processes and reveal new insights in chemistry, biology, material science and high-energy-density physics. This manuscript describes the laser systems and experimental methods that enable cutting-edge optical laser/X-ray pump–probe experiments to be performed at LCLS.

  16. American Physical Society

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Physics Hou-Tong Chen was honored for contributions to the development of active metamaterials and devices, and the development and understanding of few-layer metamaterials and...

  17. High Energy Physics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Large Scale Production Computing and Storage Requirements for High Energy Physics: Target 2017 HEPlogo.jpg The NERSC Program Requirements Review "Large Scale Computing and Storage...

  18. Noncommutative geometry and physics

    E-Print Network [OSTI]

    Jean Petitot

    2015-05-01

    This is a compilation of some well known propositions of Alain Connes concerning the use of noncommutative geometry in mathematical physics.

  19. Nuclear Physics: Experiment Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    search Nuclear Physics Program Please upgrade your browser. This site's design is only visible in a graphical browser that supports web standards, but its content is accessible to...

  20. Nuclear Physics: Experiment Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Free Electron Laser (FEL) Medical Imaging Physics Topics Campaigns Meetings Recent Talks Archived Talks Additional Information Computing at JLab Operations Logbook Experiment...