Sample records for trap atoms atom

  1. Interaction of trapped ions with trapped atoms

    E-Print Network [OSTI]

    Grier, Andrew T. (Andrew Todd)

    2011-01-01T23:59:59.000Z

    In this thesis, I present results from two Paul-trap based ion traps carried out in the Vuleti? laboratory: the Atom-Ion trap for collision studies between cold atoms and cold ions, and the Cavity-Array trap for studying ...

  2. Laser trapping of {sup 21}Na atoms

    SciTech Connect (OSTI)

    Lu, Zheng-Tian

    1994-09-01T23:59:59.000Z

    This thesis describes an experiment in which about four thousand radioactive {sup 21}Na (t{sub l/2} = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped {sup 21}Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of {sup 21}Na {yields} {sup 21}Ne + {Beta}{sup +} + v{sub e}, which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trapped atoms that we have achieved is still about two orders of magnitude lower than what is needed to conduct a measurement of the beta-asymmetry parameter at 1% of precision level, the result of this experiment proved the feasibility of trapping short-lived radioactive atoms. In this experiment, {sup 21}Na atoms were produced by bombarding {sup 24}Mg with protons of 25 MeV at the 88 in. Cyclotron of Lawrence Berkeley Laboratory. A few recently developed techniques of laser manipulation of neutral atoms were applied in this experiment. The {sup 21}Na atoms emerging from a heated oven were first transversely cooled. As a result, the on-axis atomic beam intensity was increased by a factor of 16. The atoms in the beam were then slowed down from thermal speed by applying Zeeman-tuned slowing technique, and subsequently loaded into a magneto-optical trap at the end of the slowing path. The last two chapters of this thesis present two studies on the magneto-optical trap of sodium atoms. In particular, the mechanisms of magneto-optical traps at various laser frequencies and the collisional loss mechanisms of these traps were examined.

  3. atom trap trace: Topics by E-print Network

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

    1 An atom trap trace analysis system for measuring krypton contamination in xenon dark matter detectors Physics Websites Summary: An atom trap trace analysis system for measuring...

  4. An Atom Trap Relying on Optical Pumping

    E-Print Network [OSTI]

    P. Bouyer; P. Lemonde; M. Ben Dahan; A. Michaud; C. Salomon; J. Dalibard

    2005-09-21T23:59:59.000Z

    We have investigated a new radiation pressure trap which relies on optical pumping and does not require any magnetic field. It employs six circularly polarized divergent beams and works on the red of a $J_{g} \\longrightarrow J_{e} = J_{g} + 1$ atomic transition with $J_{g} \\geq 1/2$. We have demonstrated this trap with cesium atoms from a vapour cell using the 852 nm $J_{g} = 4 \\longrightarrow J_{e} = 5$ resonance transition. The trap contained up to $3 \\cdot 10^{7}$ atoms in a cloud of $1/\\sqrt{e}$ radius of 330 $\\mu$m.

  5. Chapter 44. Cooling and Trapping Neutral Atoms Cooling and Trapping Neutral Atoms

    E-Print Network [OSTI]

    transition. This year, we made progress in developing novel detection and cooling techniques. 1. SpinChapter 44. Cooling and Trapping Neutral Atoms 44-1 Cooling and Trapping Neutral Atoms RLE Groups in optical lattices. Additional cooling methods will be needed to reach this very interesting temperature

  6. Trapping atoms using nanoscale quantum vacuum forces

    E-Print Network [OSTI]

    D. E. Chang; K. Sinha; J. M. Taylor; H. J. Kimble

    2013-10-22T23:59:59.000Z

    Quantum vacuum forces dictate the interaction between individual atoms and dielectric surfaces at nanoscale distances. For example, their large strengths typically overwhelm externally applied forces, which makes it challenging to controllably interface cold atoms with nearby nanophotonic systems. Here, we show that it is possible to tailor the vacuum forces themselves to provide strong trapping potentials. The trapping scheme takes advantage of the attractive ground state potential and adiabatic dressing with an excited state whose potential is engineered to be resonantly enhanced and repulsive. This procedure yields a strong metastable trap, with the fraction of excited state population scaling inversely with the quality factor of the resonance of the dielectric structure. We analyze realistic limitations to the trap lifetime and discuss possible applications that might emerge from the large trap depths and nanoscale confinement.

  7. Broadband laser cooling of trapped atoms with ultrafast pulses

    E-Print Network [OSTI]

    B. B. Blinov; R. N. Kohn Jr.; M. J. Madsen; P. Maunz; D. L. Moehring; C. Monroe

    2005-07-07T23:59:59.000Z

    We demonstrate broadband laser cooling of atomic ions in an rf trap using ultrafast pulses from a modelocked laser. The temperature of a single ion is measured by observing the size of a time-averaged image of the ion in the known harmonic trap potential. While the lowest observed temperature was only about 1 K, this method efficiently cools very hot atoms and can sufficiently localize trapped atoms to produce near diffraction-limited atomic images.

  8. Cooling trapped atoms in optical resonators

    E-Print Network [OSTI]

    Stefano Zippilli; Giovanna Morigi

    2007-03-20T23:59:59.000Z

    We derive an equation for the cooling dynamics of the quantum motion of an atom trapped by an external potential inside an optical resonator. This equation has broad validity and allows us to identify novel regimes where the motion can be efficiently cooled to the potential ground state. Our result shows that the motion is critically affected by quantum correlations induced by the mechanical coupling with the resonator, which may lead to selective suppression of certain transitions for the appropriate parameters regimes, thereby increasing the cooling efficiency.

  9. Radiation trapping in a cold atomic gas Guillaume Labeyrie,1

    E-Print Network [OSTI]

    field of study deals with the transport of near resonant light in such media. Using cold atoms, one can at the end of the 20th century that studies of light transport in optically thick clouds of cold atomsRadiation trapping in a cold atomic gas Guillaume Labeyrie,1 Robin Kaiser,1, and Dominique Delande

  10. Atom trap trace analysis of krypton isotopes

    SciTech Connect (OSTI)

    Bailey, K.; Chen, C. Y.; Du, X.; Li, Y. M.; Lu, Z.-T.; O'Connor, T. P.; Young, L.

    1999-11-17T23:59:59.000Z

    A new method of ultrasensitive isotope trace analysis has been developed. This method, based on the technique of laser manipulation of neutral atoms, has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton gas sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. This method is free of contamination from other isotopes and elements and can be applied to several different isotope tracers for a wide range of applications. The demonstrated detection efficiency is 1 x 10{sup {minus}7}. System improvements could increase the efficiency by many orders of magnitude.

  11. Broadband laser cooling of trapped atoms with ultrafast pulses

    E-Print Network [OSTI]

    Blinov, Boris

    Broadband laser cooling of trapped atoms with ultrafast pulses B. B. Blinov,* R. N. Kohn, Jr., M. J ions in an rf trap using ultrafast pulses from a mode-locked laser. The temperature of a single ion On the other hand, an ultrafast laser whose pulse is a few picoseconds long will naturally have a bandwidth

  12. Fast optimal frictionless atom cooling in harmonic traps

    E-Print Network [OSTI]

    Xi Chen; A. Ruschhaupt; S. Schmidt; A. del Campo; D. Guery-Odelin; J. G. Muga

    2009-10-05T23:59:59.000Z

    A method is proposed to cool down atoms in a harmonic trap without phase-space compression as in a perfectly slow adiabatic expansion, i.e., keeping the populations of the instantaneous initial and final levels invariant, but in a much shorter time. This may require that the harmonic trap becomes an expulsive parabolic potential in some time interval. The cooling times achieved are also shorter than previous minimal times using optimal-control bang-bang methods and real frequencies.

  13. Thermodynamics of Interacting Fermions in Atomic Traps

    SciTech Connect (OSTI)

    Chen Qijin; Stajic, Jelena; Levin, K. [James Franck Institute and Department of Physics, University of Chicago, Chicago, Illinois 60637 (United States)

    2005-12-31T23:59:59.000Z

    We calculate the entropy in a trapped, resonantly interacting Fermi gas as a function of temperature for a wide range of magnetic fields between the BCS and Bose-Einstein condensation end points. This provides a basis for the important technique of adiabatic sweep thermometry and serves to characterize quantitatively the evolution and nature of the excitations of the gas. The results are then used to calibrate the temperature in several ground breaking experiments on {sup 6}Li and {sup 40}K.

  14. Isotopic abundance in atom trap trace analysis

    DOE Patents [OSTI]

    Lu, Zheng-Tian; Hu, Shiu-Ming; Jiang, Wei; Mueller, Peter

    2014-03-18T23:59:59.000Z

    A method and system for detecting ratios and amounts of isotopes of noble gases. The method and system is constructed to be able to measure noble gas isotopes in water and ice, which helps reveal the geological age of the samples and understand their movements. The method and system uses a combination of a cooled discharge source, a beam collimator, a beam slower and magneto-optic trap with a laser to apply resonance frequency energy to the noble gas to be quenched and detected.

  15. Spontaneous recoil effects of optical pumping on trapped atoms

    E-Print Network [OSTI]

    S. Wallentowitz; P. E. Toschek

    2008-08-08T23:59:59.000Z

    The recoil effects of spontaneous photon emissions during optical pumping of a trapped three-level atom are exactly calculated. Without resort to the Lamb-Dicke approximation, and considering arbitrary detuning and saturation of the pump laser, the density of recoil shifts in phase space is derived. It is shown that this density is not of Gaussian shape, and that it becomes isotropic in phase space only for a branching ratio corresponding to fluorescence scattering but unfavorable for optical pumping. The dependence of its anisotropy on the laser saturation is discussed in the resonant case, and the mapping of moments of the atom's center-of-mass motion due to the pumping is presented. Moreover, it is shown how optimum parameters for protecting the center-of-mass quantum state from pump-induced disturbance depend on the specific property to be protected.

  16. Theoretical investigation of energy-trapping mechanism by atomic systems

    E-Print Network [OSTI]

    Srivastava, Rajendra P.

    1978-06-01T23:59:59.000Z

    The theoretical results are presented here in detail for the atomic device proposed earlier by the author. This device absorbs energy from a continuous radiation source and stores some of it with atoms in metastable states ...

  17. Deep superconducting magnetic traps for neutral atoms and molecules J. G. E. Harris,a)

    E-Print Network [OSTI]

    Harris, Jack

    2003 We describe the design, construction and performance of three realizations of a high of the coils into a cryogenic vacuum environment suitable for producing cold atoms and molecules. © 2004 atomic vapors away from material walls, thereby breaking thermal contact be- tween the trapped atoms

  18. Resonant interaction of trapped cold atoms with a magnetic cantilever tip

    E-Print Network [OSTI]

    Montoya, Cris; Geraci, Andrew A; Eardley, Matthew; Moreland, John; Hollberg, Leo; Kitching, John

    2015-01-01T23:59:59.000Z

    Magnetic resonance in an ensemble of laser-cooled trapped Rb atoms is excited using a micro- cantilever with a magnetic tip. The cantilever is mounted on a multi-layer chip designed to capture, cool, and magnetically transport cold atoms. The coupling is observed by measuring the loss from a magnetic trap as the oscillating cantilever induces Zeeman state transitions in the atoms. Interfacing cold atoms with mechanical devices could enable probing and manipulating atomic spins with nanometer spatial resolution and single-spin sensitivity, leading to new capabilities in quantum computation, quantum simulation, or precision sensing.

  19. Resonant interaction of trapped cold atoms with a magnetic cantilever tip

    E-Print Network [OSTI]

    Cris Montoya; Jose Valencia; Andrew A. Geraci; Matthew Eardley; John Moreland; Leo Hollberg; John Kitching

    2015-03-26T23:59:59.000Z

    Magnetic resonance in an ensemble of laser-cooled trapped Rb atoms is excited using a micro- cantilever with a magnetic tip. The cantilever is mounted on a multi-layer chip designed to capture, cool, and magnetically transport cold atoms. The coupling is observed by measuring the loss from a magnetic trap as the oscillating cantilever induces Zeeman state transitions in the atoms. Interfacing cold atoms with mechanical devices could enable probing and manipulating atomic spins with nanometer spatial resolution and single-spin sensitivity, leading to new capabilities in quantum computation, quantum simulation, or precision sensing.

  20. Heating of trapped ultracold atoms by collapse dynamics

    E-Print Network [OSTI]

    Franck Laloë; William J. Mullin; Philip Pearle

    2014-11-12T23:59:59.000Z

    {The Continuous Spontaneous Localization (CSL) theory alters the Schr\\"odinger equation. It describes wave function collapse as a dynamical process instead of an ill-defined postulate, thereby providing macroscopic uniqueness and solving the so-called measurement problem of standard quantum theory. CSL contains a parameter $\\lambda$ giving the collapse rate of an isolated nucleon in a superposition of two spatially separated states and, more generally, characterizing the collapse time for any physical situation. CSL is experimentally testable, since it predicts some behavior different from that predicted by standard quantum theory. One example is the narrowing of wave functions, which results in energy imparted to particles. Here we consider energy given to trapped ultra-cold atoms. Since these are the coldest samples under experimental investigation, it is worth inquiring how they are affected by the CSL heating mechanism. We examine the CSL heating of a BEC in contact with its thermal cloud. Of course, other mechanisms also provide heat and also particle loss. From varied data on optically trapped cesium BEC's, we present an energy audit for known heating and loss mechanisms. The result provides an upper limit on CSL heating and thereby an upper limit on the parameter $\\lambda$. We obtain $\\lambda\\lesssim 1(\\pm1)\\times 10^{-7}$sec$^{-1}$.}

  1. Velocity tuning of friction with two trapped atoms

    E-Print Network [OSTI]

    Gangloff, Dorian; Counts, Ian; Jhe, Wonho; Vuleti?, Vladan

    2015-01-01T23:59:59.000Z

    Friction is the basic, ubiquitous mechanical interaction between two surfaces that results in resistance to motion and energy dissipation. In spite of its technological and economic significance, our ability to control friction remains modest, and our understanding of the microscopic processes incomplete. At the atomic scale, mismatch between the two contacting crystal lattices can lead to a reduction of stick-slip friction (structural lubricity), while thermally activated atomic motion can give rise to a complex velocity dependence, and nearly vanishing friction at sufficiently low velocities (thermal lubricity). Atomic force microscopy has provided a wealth of experimental results, but limitations in the dynamic range, time resolution, and control at the single-atom level have hampered a full quantitative description from first principles. Here, using an ion-crystal friction emulator with single-atom, single substrate-site spatial resolution and single-slip temporal resolution, we measure the friction force...

  2. Cooling the motion of a trapped atom with a cavity field

    E-Print Network [OSTI]

    Marc Bienert; Giovanna Morigi

    2012-11-07T23:59:59.000Z

    We theoretically analyze the cooling dynamics of an atom which is tightly trapped inside a high-finesse optical resonator. Cooling is achieved by suitably tailored scattering processes, in which the atomic dipole transition either scatters a cavity photon into the electromagnetic field external to the resonator, or performs a stimulated emission into the cavity mode, which then dissipates via the cavity mirrors. We identify the parameter regimes in which the atom center-of-mass motion can be cooled into the ground state of the external trap. We predict, in particular, that for high cooperativities interference effects mediated by the atomic transition may lead to higher efficiencies. The dynamics is compared with the cooling dynamics of a trapped atom inside a resonator studied in [Phys. Rev. Lett. 95, 143001, (2005)] where the atom, instead of the cavity, is driven by a laser field.

  3. Enhanced Raman sideband cooling of caesium atoms in a vapour-loaded magneto-optical trap

    E-Print Network [OSTI]

    Li, Y; Feng, G; Nute, J; Piano, S; Hackermuller, L; Ma, J; Xiao, L; Jia, S

    2015-01-01T23:59:59.000Z

    We report enhanced three-dimensional degenerated Raman sideband cooling (3D DRSC) of caesium (Cs) atoms in a standard single-cell vapour-loading magneto-optical trap. Our improved scheme involves using a separate repumping laser and optimized lattice detuning. We load $1.5 \\times 10^7$ atoms into the Raman lattice with a detuning of -15.5 GHz (to the ground F = 3 state). Enhanced 3D DRSC is used to cool them from 60 $\\mu$K to 1.7 $\\mu$K within 12 ms and the number of obtained atoms is about $1.2 \\times 10^7$. A theoretical model is proposed to simulate the measured number of trapped atoms. The result shows good agreement with the experimental data. The technique paves the way for loading a large number of ultracold Cs atoms into a crossed dipole trap and efficient evaporative cooling in a single-cell system.

  4. Semilinear response for the heating rate of cold atoms in vibrating traps

    E-Print Network [OSTI]

    Cohen, Doron

    OFFPRINT Semilinear response for the heating rate of cold atoms in vibrating traps A. Stotland, D;Europhysics Letters (EPL) has a new online home at www.epljournal.org Take a look for the latest journal news.epljournal.org doi: 10.1209/0295-5075/86/10004 Semilinear response for the heating rate of cold atoms in vibrating

  5. ccsd-00005837,version2-10Jul2005 Partially ferromagnetic electromagnet for trapping and cooling neutral atoms to

    E-Print Network [OSTI]

    Boyer, Edmond

    lasers. INTRODUCTION The realization of Bose-Einstein condensates (BECs) of a dilute gas of trapped atoms of 87 Rb atoms to quantum degeneracy. Pure Bose-Einstein condensates containing 106 atoms are routinely, 9]. It is therefore expected that the use of Bose-Einstein condensed atoms will advance the field

  6. Nanowire photonic crystal waveguides for single-atom trapping and strong light-matter interactions

    SciTech Connect (OSTI)

    Yu, S.-P.; Hood, J. D.; Muniz, J. A.; Martin, M. J.; Hung, C.-L.; Kimble, H. J., E-mail: hjkimble@caltech.edu [Norman Bridge Laboratory of Physics 12-33, California Institute of Technology, Pasadena, California 91125 (United States); Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125 (United States); Norte, Richard; Meenehan, Seán M.; Cohen, Justin D.; Painter, Oskar, E-mail: opainter@caltech.edu [Institute for Quantum Information and Matter, California Institute of Technology, Pasadena, California 91125 (United States); Thomas J. Watson, Sr., Laboratory of Applied Physics 128-95, California Institute of Technology, Pasadena, California 91125 (United States)

    2014-03-17T23:59:59.000Z

    We present a comprehensive study of dispersion-engineered nanowire photonic crystal waveguides suitable for experiments in quantum optics and atomic physics with optically trapped atoms. Detailed design methodology and specifications are provided, as are the processing steps used to create silicon nitride waveguides of low optical loss in the near-IR. Measurements of the waveguide optical properties and power-handling capability are also presented.

  7. Modeling and control of entanglement dynamics in laser cooling of trapped atoms

    E-Print Network [OSTI]

    Maryam Roghani; Heinz-Peter Breuer; Hanspeter Helm

    2011-08-01T23:59:59.000Z

    We discuss the dynamical behavior of the entanglement between the internal and the external degrees of freedom of a trapped atom in electromagnetically-induced transparency (EIT) laser cooling. It is shown that essential features of the intricate entanglement dynamics observed in full numerical simulations of the underlying quantum master equation can be understood in terms of a two-state model on the basis of Landau-Zener splittings in the atom-laser field Hamiltonian. An extension of this model to an effective non-Hermitian Hamiltonian is constructed which describes the decay of entanglement by spontaneous emission processes. We also discuss schemes for the control of entanglement and demonstrate that a permanent entanglement can be imprinted on trapped atoms through a rapid switch off of the driving fields. Finally, we point out fundamental distinctions between the entanglement created in EIT cooling and in the cooling scheme based on velocity-selective coherent population trapping.

  8. Fractal templates in the escape dynamics of trapped ultracold atoms Kevin A. Mitchell

    E-Print Network [OSTI]

    Steck, Daniel A.

    Fractal templates in the escape dynamics of trapped ultracold atoms Kevin A. Mitchell School nonlinear dynamics, we predict that fractal behavior can be seen in experimental escape data. These data can. This fractal pattern is particularly well resolved below the Bose-Einstein transition temperature--a direct

  9. An atom trap trace analysis (ATTA) system for measuring ultra-low contamination by krypton in

    E-Print Network [OSTI]

    Zelevinsky, Tanya

    An atom trap trace analysis (ATTA) system for measuring ultra-low contamination by krypton in xenon ultra-low contamination by krypton in xenon dark matter detectors Tae Hyun Yoon The XENON dark matter analysis (ATTA) device to detect the ultra-low kryp- ton concentration in the xenon target. This project

  10. Trapping and Manipulation of Isolated Atoms Using Nanoscale Plasmonic Structures D. E. Chang,1

    E-Print Network [OSTI]

    Heller, Eric

    - and nanopho- tonic structures [8­10] [see Fig. 1(a)]. Alternatively, hybrid quantum systems consisting, heating and decoherence rates acting on the trapped atom. DOI: 10.1103/PhysRevLett.103.123004 PACS numbers: 37.10.Gh, 42.50.Àp, 73.20.Mf, 78.67.Bf Much interest has recently been directed towards hybrid

  11. Storage of fiber-guided light in a nanofiber-trapped ensemble of cold atoms

    E-Print Network [OSTI]

    C. Sayrin; C. Clausen; B. Albrecht; P. Schneeweiss; A. Rauschenbeutel

    2015-02-04T23:59:59.000Z

    Tapered optical fibers with a nanofiber waist are versatile tools for interfacing light and matter. In this context, laser-cooled atoms trapped in the evanescent field surrounding the optical nanofiber are of particular interest: They exhibit both long ground-state coherence times and efficient coupling to fiber-guided fields. Here, we demonstrate electromagnetically induced transparency, slow light, and the storage of fiber-guided optical pulses in an ensemble of cold atoms trapped in a nanofiber-based optical lattice. We measure a slow-down of light pulses to group velocities of 50 m/s. Moreover, we store optical pulses at the single photon level and retrieve them on demand in the fiber after 2 microseconds with an overall efficiency of (3.0 +/- 0.4) %. Our results show that nanofiber-based interfaces for cold atoms have great potential for the realization of building blocks for future optical quantum information networks.

  12. Preparation of a high concentration of lithium-7 atoms in a magneto-optical trap

    SciTech Connect (OSTI)

    Zelener, B. B., E-mail: bobozel@mail.ru; Saakyan, S. A.; Sautenkov, V. A. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation); Manykin, E. A. [National Research Nuclear University “Moscow Engineering Physics Institute,” (Russian Federation); Zelener, B. V.; Fortov, V. E. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)

    2014-11-15T23:59:59.000Z

    This study is aimed at obtaining high concentration of optically cooled lithium-7 atoms for preparing strongly interacting ultracold plasma and Rydberg matter. A special setup has been constructed, in which two high-power semiconductor lasers are used to cool lithium-7 atoms in a magneto-optical trap. At an optimum detuning of the cooling laser frequency and a magnetic field gradient of 35 G/cm, the concentration of ultracold lithium-7 atoms reaches about 10{sup 11} cm{sup ?3}. Additional independent information about the concentration and number of ultracold lithium-7 atoms on different sublevels of the ground state was obtained by using of an additional probing laser.

  13. Impact of the Meissner effect on magnetic micro traps for neutral atoms near superconducting thin films

    E-Print Network [OSTI]

    D. Cano; B. Kasch; H. Hattermann; D. Koelle; R. Kleiner; C. Zimmermann; J. Fortágh

    2008-08-21T23:59:59.000Z

    We theoretically evaluate changes in the magnetic potential arising from the magnetic field near superconducting thin films. An example of an atom chip based on a three-wire configuration has been simulated in the superconducting and the normal conducting state. Inhomogeneous current densities within the superconducting wires were calculated using an energy-minimization routine based on the London theory. The Meissner effect causes changes to both trap position and oscillation frequencies at short distances from the superconducting surface. Superconducting wires produce much shallower micro traps than normal conducting wires. The results presented in this paper demonstrate the importance of taking the Meissner effect into account when designing and carrying out experiments on magnetically trapped neutral atoms near superconducting surfaces.

  14. Laser scattering by density fluctuations of ultra-cold atoms in a magneto-optical trap

    E-Print Network [OSTI]

    J. T. Mendonça; H. Terças

    2011-04-06T23:59:59.000Z

    We study the spectrum of density fluctuations in the ultra-cold gas of neutral atoms, confined in a magneto-optical trap. We determine the corresponding amplitude and spectra of laser light scattered by this medium. We derive an expression for the dynamical structure function, by using a test particle method. We propose to use the collective laser scattering as a diagnostic method for the microscopic properties of the ultra-cold matter. This will also allow us to check on the atomic correlations which are mediated by the collective mean field inside the gas.

  15. Cavity cooling of a trapped atom using Electromagnetically-Induced Transparency

    E-Print Network [OSTI]

    Marc Bienert; Giovanna Morigi

    2011-12-01T23:59:59.000Z

    A cooling scheme for trapped atoms is proposed, which combines cavity-enhanced scattering and electromagnetically induced transparency. The cooling dynamics exploits a three-photon resonance, which combines laser and cavity excitations. It is shown that relatively fast ground-state cooling can be achieved in the Lamb-Dicke regime and for large cooperativity. Efficient ground-state cooling is found for parameters of ongoing experiments.

  16. Influence of coherent Raman scattering on coherent population trapping in atomic sodium vapor

    SciTech Connect (OSTI)

    Wong, Vincent; Bennink, Ryan S.; Marino, Alberto M.; Boyd, Robert W.; Stroud, C.R. Jr.; Narducci, F.A. [Institute of Optics, University of Rochester, Rochester, New York 14627 (United States); EO Sensors Division, Naval Air Systems Command, Patuxent River, Maryland 20670 (United States)

    2004-11-01T23:59:59.000Z

    We study how coherent Stokes and anti-Stokes Raman scattering influence coherent population trapping. In an experiment using an atomic sodium vapor cell we observe induced transparency, induced absorption, and gain features, all of subnatural linewidth. The electromagnetically induced resonance is a peak or a dip depending on which side of the optical transition the fields are tuned to, and thus whether coherent anti-Stokes Raman scattering or coherent Stokes Raman scattering is the dominant process.

  17. Exploring Ramsey-coherent population trapping atomic clock realized with pulsed microwave modulated laser

    SciTech Connect (OSTI)

    Yang, Jing; Yun, Peter [Key Laboratory of Atomic Frequency Standards, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Tian, Yuan; Tan, Bozhong [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China); Gu, Sihong, E-mail: shgu@wipm.ac.cn [Key Laboratory of Atomic Frequency Standards, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-03-07T23:59:59.000Z

    A scheme for a Ramsey-coherent population trapping (CPT) atomic clock that eliminates the acousto-optic modulator (AOM) is proposed and experimentally studied. Driven by a periodically microwave modulated current, the vertical-cavity surface-emitting laser emits a continuous beam that switches between monochromatic and multichromatic modes. Ramsey-CPT interference has been studied with this mode-switching beam. In eliminating the AOM, which is used to generate pulsed laser in conventional Ramsey-CPT atomic clock, the physics package of the proposed scheme is virtually the same as that of a conventional compact CPT atomic clock, although the resource budget for the electronics will slightly increase as a microwave switch should be added. By evaluating and comparing experimentally recorded signals from the two Ramsey-CPT schemes, the short-term frequency stability of the proposed scheme was found to be 46% better than the scheme with AOM. The experimental results suggest that the implementation of a compact Ramsey-CPT atomic clock promises better frequency stability.

  18. Fast nondestructive temperature measurement of two-electron atoms in a magneto-optical trap

    SciTech Connect (OSTI)

    Cristiani, Matteo; Valenzuela, Tristan; Gothe, Hannes; Eschner, Juergen [ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, E-08860 Castelldefels (Barcelona) (Spain)

    2010-06-15T23:59:59.000Z

    We extend the technique originally proposed by [Honda et al., Phys. Rev. A 59, R934 (1999)] to measure the temperature of ytterbium and alkaline-earth-metal atoms confined in a magneto-optical trap (MOT). The method is based on the analysis of excitation spectra obtained by probing the {sup 1}S{sub 0}{yields}{sup 3}P{sub 1} intercombination line. Thanks to a careful analysis and modeling of the effects caused by the MOT light on the probe transition we overcome the resolution and precision limits encountered in previous works. Ground-state light shift and Rabi broadening are measured and successfully compared with calculated values. This knowledge allows us to properly extract the Doppler contribution to the linewidth, thus obtaining a reliable measurement of the cloud temperature. We finally show how spectroscopy on free-falling atoms provides an alternative method to determine the sample temperature which resembles the standard time-of-flight technique.

  19. Alfvén ion-cyclotron instability in an axisymmetric trap with oblique injection of fast atoms

    SciTech Connect (OSTI)

    Tsidulko, Yu. A.; Chernoshtanov, I. S., E-mail: cherivn@ngs.ru [Russian Academy of Sciences, Budker Institute of Nuclear Physics (Russian Federation)

    2014-12-15T23:59:59.000Z

    Conditions for the onset of Alfvén ion-cyclotron instability and the spatial structure of unstable modes in an axisymmetric mirror trap with oblique injection of fast atoms are studied. It is shown that the main contribution to instability comes from the inverse population of ions in the velocity space domain into which atoms are injected. Using the distribution function of fast ions obtained by approximately solving the Fokker-Planck equation, the instability threshold in terms of ?{sub ?} is determined in the Wentzel-Kramers-Brillouin approximation as a function of the geometric parameters and the parameters of injection and target plasma. It is demonstrated that the stability threshold increases substantially when the radius of the hot plasma decreases to a size comparable with the Larmor radius of fast ions. It is shown that the perturbed fields near the axis and at the plasma periphery can rotate in opposite directions, which is important for the interpretation of experimental data.

  20. Atom Trap Trace Analysis at ANL | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurTheBrookhaven NationalRegionals » HighAbstractsAprilArgonneArkansasAtom Trap

  1. Combining red- and blue-detuned optical potentials to form a Lamb-Dicke trap for a single neutral atom

    E-Print Network [OSTI]

    Xiaodong He; Peng Xu; Jin Wang; Mingsheng Zhan

    2012-02-03T23:59:59.000Z

    We propose and demonstrate a scheme for strongly radially confining a single neutral atom in a bichromatic far-off resonance optical dipole trap(BFORT) . BFORT is composed of a blue-detuned Laguerre-Gaussian $LG^1_ 0$ beam and a red-detuned Gaussian beam. The trapping radial dimension of a single atom trapped in the Gaussian FORT can be greatly compressed by imposing a blue-detuned Laguerre-Gaussian $LG^1_ 0$ beam with moderate potential depth. By modulating the potential depth of the Gaussian FORT we observed that the resonant and parametric excitation of the oscillatory motion of a single atom in this BFORT and obtained the oscillation frequency that well fits prediction from the theoretical model. The frequency measurement shows that effective trapping dimension can be greatly sharper than that diffraction limited of microscopic objective we used. Then we show that the excess scattering rate due to imposing blue detuned light can be eliminated when single atoms is close to ground-state theoretically. So BFORT suits the purpose of acting as a Lamb-Dicke trap for further cooling a single neutral atom to motion ground-state and finding application in quantum information progressing.

  2. Production and trapping of radioactive atoms at the TRI\\muP facility

    E-Print Network [OSTI]

    E. Traykov; U. Dammalapati; S. De; O. C. Dermois; L. Huisman; K. Jungmann; W. Kruithof; A. J. Mol; C. J. G. Onderwater; A. Rogachevskiy; M. da Silva e Silva; M. Sohani; O. Versolato; L. Willmann; H. W. Wilschut

    2008-03-28T23:59:59.000Z

    The structures for the TRI$\\mu$P facility have been completed and commissioned. At the facility radioactive nuclides are produced to study fundamental interactions and symmetries. An important feature is the possibility to trap radioactive atoms in order to obtain and hold a pure substrate-free sample for precision measurements. In the TRI$\\mu$P facility a production target is followed by a magnetic separator, where radioactive isotopes are produced in inverse reaction kinematics. Separation up to 99.95% could be achieved for $^{21}$Na. A novel transmitting thermal ionizing device was developed to stop the energetic isotopes. Some 50% of stopped $^{21}$Na could be extracted and transported as low energy singly charged ions into a radio frequency quadrupole cooler and buncher with 35% transmission efficiency. The ions are transported lossless via a drift tube and a low energy electrostatic beam line into the experimental setup. Such ions can be neutralized on hot metal foils and the resulting atoms can be stored in a magneto-optical trap. The functioning of that principle was demonstrated with stable Na extracted from the thermal ionizer, radioactive beams will follow next.

  3. Blue-detuned evanescent field surface traps for neutral atoms based on mode interference in ultra-thin optical fibres

    E-Print Network [OSTI]

    G. Sague; A. Baade; A. Rauschenbeutel

    2008-06-24T23:59:59.000Z

    We present and analyze a novel concept for blue-detuned evanescent field surface traps for cold neutral atoms based on two-mode interference in ultra-thin optical fibres. When two or more transverse modes with the same frequency co-propagate in the fibre, their different phase velocities cause a stationary interference pattern to establish. Intensity minima of the evanescent field at any distance from the fibre surface can be created and an array of optical microtraps can thus be obtained in the evanescent field. We discuss three possible combinations of the lowest order modes, yielding traps at one to two hundred nanometres from the fibre surface which, using a few ten milliwatts of trapping laser power, have a depth on the order of 1 mK for caesium atoms and a trapping lifetime exceeding 100 seconds. The resulting trapping geometry is of particular interest because atoms in such microtrap arrays will be coupled to any additional field propagating in the fibre via the evanescent field, thereby realising ensembles of fibre-coupled atoms.

  4. Strong interaction between light and a single trapped atom without a cavity

    E-Print Network [OSTI]

    Meng Khoon Tey; Zilong Chen; Syed Abdullah Aljunid; Brenda Chng; Florian Huber; Gleb Maslennikov; Christian Kurtsiefer

    2008-06-12T23:59:59.000Z

    Coupling of light to an atom at single quanta level with high probability is a building block for many quantum information processing protocols. It is commonly believed that efficient coupling is only achievable with the assistance of a cavity. Here, we report on an observation of substantial coupling between a light beam and a single $^{87}$Rb atom in a direct extinction measurement by focusing light to a small spot with a single lens. Our result opens a new perspective on processing quantum information carried by light using atoms, and is important to many ongoing experiments that require strong coupling of single photons to an atom in free space.

  5. Photoionization of optically trapped ultracold atoms with a high-power light-emitting diode

    SciTech Connect (OSTI)

    Goetz, Simone; Hoeltkemeier, Bastian; Amthor, Thomas; Weidemueller, Matthias [Physikalisches Institut, Universitaet Heidelberg, Im Neuenheimer Feld 226, 69120 Heidelberg (Germany)

    2013-04-15T23:59:59.000Z

    Photoionization of laser-cooled atoms using short pulses of a high-power light-emitting diode (LED) is demonstrated. Light pulses as short as 30 ns have been realized with the simple LED driver circuit. We measure the ionization cross section of {sup 85}Rb atoms in the first excited state, and show how this technique can be used for calibrating efficiencies of ion detector assemblies.

  6. Atom Interferometry

    ScienceCinema (OSTI)

    Mark Kasevich

    2010-01-08T23:59:59.000Z

    Atom de Broglie wave interferometry has emerged as a tool capable of addressing a diverse set of questions in gravitational and condensed matter physics, and as an enabling technology for advanced sensors in geodesy and navigation. This talk will review basic principles, then discuss recent applications and future directions. Scientific applications to be discussed include measurement of G (Newton?s constant), tests of the Equivalence Principle and post-Newtonian gravity, and study of the Kosterlitz-Thouless phase transition in layered superfluids. Technology applications include development of precision gryoscopes and gravity gradiometers. The talk will conclude with speculative remarks looking to the future: Can atom interference methods be sued to detect gravity waves? Can non-classical (entangled/squeezed state) atom sources lead to meaningful sensor performance improvements?

  7. Fluorescence during Doppler cooling of a single trapped atom J. H. Wesenberg,* R. J. Epstein,

    E-Print Network [OSTI]

    . Leibfried, R. B. Blakestad, J. Britton, J. P. Home, W. M. Itano, J. D. Jost, E. Knill, C. Langer, R. Ozeri of this temperature measurement provides a way to measure atom heating rates by observing the temperature rise field. After cooling and heating effects related to micromotion were observed, these effects were

  8. Long-range sound-mediated dark-soliton interactions in trapped atomic condensates

    SciTech Connect (OSTI)

    Allen, A. J.; Jackson, D. P.; Barenghi, C. F.; Proukakis, N. P. [School of Mathematics and Statistics, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom)

    2011-01-15T23:59:59.000Z

    A long-range soliton interaction is discussed whereby two or more dark solitons interact in an inhomogeneous atomic condensate, modifying their respective dynamics via the exchange of sound waves without ever coming into direct contact. An idealized double-well geometry is shown to yield perfect energy transfer and complete periodic identity reversal of the two solitons. Two experimentally relevant geometries are analyzed which should enable the observation of this long-range interaction.

  9. Calibration of a single atom detector for atomic micro chips

    E-Print Network [OSTI]

    A. Stibor; S. Kraft; T. Campey; D. Komma; A. Günther; J. Fortágh; C. J. Vale; H. Rubinsztein-Dunlop; C. Zimmermann

    2007-02-13T23:59:59.000Z

    We experimentally investigate a scheme for detecting single atoms magnetically trapped on an atom chip. The detector is based on the photoionization of atoms and the subsequent detection of the generated ions. We describe the characterization of the ion detector with emphasis on its calibration via the correlation of ions with simultaneously generated electrons. A detection efficiency of 47.8% (+-2.6%) is measured, which is useful for single atom detection, and close to the limit allowing atom counting with sub-Poissonian uncertainty.

  10. Measuring Atomic Properties with an Atom Interferometer

    E-Print Network [OSTI]

    Roberts, Tony David

    2006-06-28T23:59:59.000Z

    Two experiments are presented which measure atomic properties using an atom interferometer. The interferometer splits the sodium de Broglie wave into two paths,

  11. Atom-light interactions in ultracold anisotropic media

    E-Print Network [OSTI]

    Vengalattore, Mukund T., 1977-

    2005-01-01T23:59:59.000Z

    A series of studies on atom-light interactions in ultracold anisotropic media were conducted. Methods to trap ultracold neutral atoms in novel traps with widely tunable trap frequencies and anisotropies were investigated. ...

  12. Realization of a superconducting atom chip

    E-Print Network [OSTI]

    Thomas Nirrengarten; Angie Qarry; Cédric Roux; Andreas Emmert; Gilles Nogues; Michel Brune; Jean-Michel Raimond; Serge Haroche

    2006-10-09T23:59:59.000Z

    We have trapped rubidium atoms in the magnetic field produced by a superconducting atom chip operated at liquid Helium temperatures. Up to $8.2\\cdot 10^5$ atoms are held in a Ioffe-Pritchard trap at a distance of 440 $\\mu$m from the chip surface, with a temperature of 40 $\\mu$K. The trap lifetime reaches 115 s at low atomic densities. These results open the way to the exploration of atom--surface interactions and coherent atomic transport in a superconducting environment, whose properties are radically different from normal metals at room temperature.

  13. Accelerometer using atomic waves for space applications

    E-Print Network [OSTI]

    of Bose-Einstein condensation (BEC) of a dilute gas of trapped atoms in a single quantum state [18, 19, 20 of such devices in the field of navigation, surveying and analysis of earth structures. Matter-wave interferometry that the use of Bose-Einstein condensed atoms will bring the science of atom optics, and in particular atom

  14. Atomic magnetometer

    DOE Patents [OSTI]

    Schwindt, Peter (Albuquerque, NM); Johnson, Cort N. (Albuquerque, NM)

    2012-07-03T23:59:59.000Z

    An atomic magnetometer is disclosed which uses a pump light beam at a D1 or D2 transition of an alkali metal vapor to magnetically polarize the vapor in a heated cell, and a probe light beam at a different D2 or D1 transition to sense the magnetic field via a polarization rotation of the probe light beam. The pump and probe light beams are both directed along substantially the same optical path through an optical waveplate and through the heated cell to an optical filter which blocks the pump light beam while transmitting the probe light beam to one or more photodetectors which generate electrical signals to sense the magnetic field. The optical waveplate functions as a quarter waveplate to circularly polarize the pump light beam, and as a half waveplate to maintain the probe light beam linearly polarized.

  15. atomic photoabsorption process: Topics by E-print Network

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

    individual sites within atom-trap arrays. Cecilia Muldoon; Lukas Brandt; Jian Dong; Dustin Stuart; Edouard Brainis; Matthew Himsworth; Axel Kuhn 2012-03-21 306 Atomic...

  16. Measuring molecular electric dipoles using trapped atomic ions and ultrafast laser pulses

    E-Print Network [OSTI]

    Jordi Mur-Petit; Juan José García-Ripoll

    2015-01-12T23:59:59.000Z

    We study a hybrid quantum system composed of an ion and an electric dipole. We show how a trapped ion can be used to measure the small electric field generated by a classical dipole. We discuss the application of this scheme to measure the electric dipole moment of cold polar molecules, whose internal state can be controlled with ultrafast laser pulses, by trapping them in the vicinity of a trapped ion.

  17. An ultra-bright atom laser

    E-Print Network [OSTI]

    V. Bolpasi; N. K. Efremidis; M. J. Morrissey; P. Condylis; D. Sahagun; M. Baker; W. von Klitzing

    2013-11-25T23:59:59.000Z

    We present a novel, ultra-bright atom-laser and ultra-cold thermal atom beam. Using rf-radiation we strongly couple the magnetic hyperfine levels of 87Rb atoms in a magnetically trapped Bose-Einstein condensate. At low rf-frequencies gravity opens a small hole in the trapping potenital and a well collimated, extremely bright atom laser emerges from just below the condensate. As opposed to traditional atom lasers based on weak coupling, this technique allows us to outcouple atoms at an arbitrarily large rate. We demonstrate an increase in flux per atom in the BEC by a factor of sixteen compared to the brightest quasi-continuous atom laser. Furthermore, we produce by two orders of magnitude the coldest thermal atom beam to date (200 nK).

  18. atom-atom collisions: Topics by E-print Network

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

    Atomic Safronova, Marianna 3 Atom-atom correlations in colliding Bose-Einstein condensates Quantum Physics (arXiv) Summary: We analyze atom-atom correlations in the s-wave...

  19. Recent Progress in ultracold atoms

    E-Print Network [OSTI]

    Baltisberger, Jay H.

    , cold gas experiments 2. How to make a BEC out of fermions 3. Recent Progress: Controlling Interaction (Feshbach Resonance) 4. From BCS to BEC: Rotating trap and spin- polarized condensates. 5. Future research and Einstein What is Bose-Einstein condensation (BEC)? #12;300 K to 1 mK 109 atoms 1 mK to 1 mK 108 106 atoms

  20. Atomizing nozzle and process

    DOE Patents [OSTI]

    Anderson, I.E.; Figliola, R.S.; Molnar, H.M.

    1993-07-20T23:59:59.000Z

    High pressure atomizing nozzle includes a high pressure gas manifold having a divergent expansion chamber between a gas inlet and arcuate manifold segment to minimize standing shock wave patterns in the manifold and thereby improve filling of the manifold with high pressure gas for improved melt atomization. The atomizing nozzle is especially useful in atomizing rare earth-transition metal alloys to form fine powder particles wherein a majority of the powder particles exhibit particle sizes having near-optimum magnetic properties.

  1. Atomic swelling upon compression

    E-Print Network [OSTI]

    V. K. Dolmatov; J. L. King

    2012-08-18T23:59:59.000Z

    The hydrogen atom under the pressure of a spherical penetrable confinement potential of a decreasing radius $r_{0}$ is explored, as a case study. A novel counter-intuitive effect of atomic swelling rather than shrinking with decreasing $r_{0}$ is unraveled, when $r_{0}$ reaches, and remains smaller than, a certain critical value. Upon swelling, the size of the atom is shown to increase by an order of magnitude, or more, compared to the size of the free atom. Examples of changes of photoabsorption properties of confined hydrogen atom upon its swelling are uncovered and demonstrated.

  2. Improved graphite furnace atomizer

    DOE Patents [OSTI]

    Siemer, D.D.

    1983-05-18T23:59:59.000Z

    A graphite furnace atomizer for use in graphite furnace atomic absorption spectroscopy is described wherein the heating elements are affixed near the optical path and away from the point of sample deposition, so that when the sample is volatilized the spectroscopic temperature at the optical path is at least that of the volatilization temperature, whereby analyteconcomitant complex formation is advantageously reduced. The atomizer may be elongated along its axis to increase the distance between the optical path and the sample deposition point. Also, the atomizer may be elongated along the axis of the optical path, whereby its analytical sensitivity is greatly increased.

  3. Atomic Collapse Observed

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

    Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 | Tags: Hopper, Materials Science Contact: Linda...

  4. Symposium on atomic spectroscopy (SAS-83): abstracts and program

    SciTech Connect (OSTI)

    Not Available

    1983-09-01T23:59:59.000Z

    Abstracts of papers given at the symposium are presented. Session topics include: Rydbergs, optical radiators, and planetary atoms; highly ionized atoms; ultraviolet radiation; theory, ion traps, and laser cooling; beam foil; and astronomy. (GHT)

  5. atomic fermi gas: Topics by E-print Network

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

    atomic Fermi gases. G. M. Bruun 2002-10-29 4 Fermi excitations in a trapped atomic Fermi gas with a molecular Bose condensate Condensed Matter (arXiv) Summary: We discuss the...

  6. Producing and Detecting Correlated atoms

    E-Print Network [OSTI]

    Christoph I. Westbrook; Martijn Schellekens; Aurélien Perrin; Valentina Krachmalnicoff; Jose Carlos Viana Gomes; Jean-Baptiste Trebbia; Jérôme Estève; Hong Chang; Isabelle Bouchoule; Denis Boiron; Alain Aspect; Tom Jeltes; John McNamara; Wim Hogervorst; Wim Vassen

    2006-09-04T23:59:59.000Z

    We discuss experiments to produce and detect atom correlations in a degenerate or nearly degenerate gas of neutral atoms. First we treat the atomic analog of the celebrated Hanbury Brown Twiss experiment, in which atom correlations result simply from interference effects without any atom interactions.We have performed this experiment for both bosons and fermions. Next we show how atom interactions produce correlated atoms using the atomic analog of spontaneous four-wavemixing. Finally, we briefly mention experiments on a one dimensional gas on an atom chip in which correlation effects due to both interference and interactions have been observed.

  7. Remote preparation of an atomic quantum memory

    E-Print Network [OSTI]

    Wenjamin Rosenfeld; Stefan Berner; Juergen Volz; Markus Weber; Harald Weinfurter

    2006-08-29T23:59:59.000Z

    Storage and distribution of quantum information are key elements of quantum information processing and quantum communication. Here, using atom-photon entanglement as the main physical resource, we experimentally demonstrate the preparation of a distant atomic quantum memory. Applying a quantum teleportation protocol on a locally prepared state of a photonic qubit, we realized this so-called remote state preparation on a single, optically trapped 87Rb atom. We evaluated the performance of this scheme by the full tomography of the prepared atomic state, reaching an average fidelity of 82%.

  8. analytical atomic spectrometry: Topics by E-print Network

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

    cooling of trapped atoms is described as a sequence of truncation of the high energy for arbitrary power-law potentials. The threshold density for accelerated evaporation...

  9. atomic transition arrays: Topics by E-print Network

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

    individual sites within atom-trap arrays. Cecilia Muldoon; Lukas Brandt; Jian Dong; Dustin Stuart; Edouard Brainis; Matthew Himsworth; Axel Kuhn 2012-03-21 412 Interstellar...

  10. Atomic and molecular supernovae

    SciTech Connect (OSTI)

    Liu, W.

    1997-12-01T23:59:59.000Z

    Atomic and molecular physics of supernovae is discussed with an emphasis on the importance of detailed treatments of the critical atomic and molecular processes with the best available atomic and molecular data. The observations of molecules in SN 1987A are interpreted through a combination of spectral and chemical modelings, leading to strong constraints on the mixing and nucleosynthesis of the supernova. The non-equilibrium chemistry is used to argue that carbon dust can form in the oxygen-rich clumps where the efficient molecular cooling makes the nucleation of dust grains possible. For Type Ia supernovae, the analyses of their nebular spectra lead to strong constraints on the supernova explosion models.

  11. Metal atomization spray nozzle

    DOE Patents [OSTI]

    Huxford, T.J.

    1993-11-16T23:59:59.000Z

    A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal. 6 figures.

  12. Atomizing nozzle and method

    DOE Patents [OSTI]

    Ting, Jason (Ames, IA); Anderson, Iver E. (Ames, IA); Terpstra, Robert L. (Ames, IA)

    2000-03-16T23:59:59.000Z

    A high pressure close-coupled gas atomizing nozzle includes multiple discrete gas jet discharge orifices having aerodynamically designed convergent-divergent geometry with an first converging section communicated to a gas supply manifold and to a diverging section by a constricted throat section to increase atomizing gas velocity. The gas jet orifices are oriented at gas jet apex angle selected relative to the melt supply tip apex angle to establish a melt aspiration condition at the melt supply tip.

  13. Optical atomic magnetometer

    DOE Patents [OSTI]

    Budker, Dmitry; Higbie, James; Corsini, Eric P

    2013-11-19T23:59:59.000Z

    An optical atomic magnetometers is provided operating on the principles of nonlinear magneto-optical rotation. An atomic vapor is optically pumped using linearly polarized modulated light. The vapor is then probed using a non-modulated linearly polarized light beam. The resulting modulation in polarization angle of the probe light is detected and used in a feedback loop to induce self-oscillation at the resonant frequency.

  14. Atomic mass compilation 2012

    SciTech Connect (OSTI)

    Pfeiffer, B., E-mail: bpfeiffe@uni-mainz.de [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Venkataramaniah, K. [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India)] [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India); Czok, U. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany)] [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); Scheidenberger, C. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany) [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany)

    2014-03-15T23:59:59.000Z

    Atomic mass reflects the total binding energy of all nucleons in an atomic nucleus. Compilations and evaluations of atomic masses and derived quantities, such as neutron or proton separation energies, are indispensable tools for research and applications. In the last decade, the field has evolved rapidly after the advent of new production and measuring techniques for stable and unstable nuclei resulting in substantial ameliorations concerning the body of data and their precision. Here, we present a compilation of atomic masses comprising the data from the evaluation of 2003 as well as the results of new measurements performed. The relevant literature in refereed journals and reports as far as available, was scanned for the period beginning 2003 up to and including April 2012. Overall, 5750 new data points have been collected. Recommended values for the relative atomic masses have been derived and a comparison with the 2003 Atomic Mass Evaluation has been performed. This work has been carried out in collaboration with and as a contribution to the European Nuclear Structure and Decay Data Network of Evaluations.

  15. Driven Ratchets for Cold Atoms

    E-Print Network [OSTI]

    Renzoni, F

    2011-01-01T23:59:59.000Z

    Brownian motors, or ratchets, are devices which "rectify" Brownian motion, i.e. they can generate a current of particles out of unbiased fluctuations. The ratchet effect is a very general phenomenon which applies to a wide range of physical systems, and indeed ratchets have been realized with a variety of solid state devices, with optical trap setups as well as with synthetic molecules and granular gases. The present article reviews recent experimental realizations of ac driven ratchets with cold atoms in driven optical lattices. This is quite an unusual system for a Brownian motor as there is no a real thermal bath, and both the periodic potential for the atoms and the fluctuations are determined by laser fields. Such a system allowed us to realize experimentally rocking and gating ratchets, and to precisely investigate the relationship between symmetry and transport in these ratchets, both for the case of periodic and quasiperiodic driving.

  16. Driven Ratchets for Cold Atoms

    E-Print Network [OSTI]

    F. Renzoni

    2011-12-05T23:59:59.000Z

    Brownian motors, or ratchets, are devices which "rectify" Brownian motion, i.e. they can generate a current of particles out of unbiased fluctuations. The ratchet effect is a very general phenomenon which applies to a wide range of physical systems, and indeed ratchets have been realized with a variety of solid state devices, with optical trap setups as well as with synthetic molecules and granular gases. The present article reviews recent experimental realizations of ac driven ratchets with cold atoms in driven optical lattices. This is quite an unusual system for a Brownian motor as there is no a real thermal bath, and both the periodic potential for the atoms and the fluctuations are determined by laser fields. Such a system allowed us to realize experimentally rocking and gating ratchets, and to precisely investigate the relationship between symmetry and transport in these ratchets, both for the case of periodic and quasiperiodic driving.

  17. Universal bosonic tetramers of dimer-atom-atom structure

    E-Print Network [OSTI]

    A. Deltuva

    2012-03-28T23:59:59.000Z

    Unstable four-boson states having an approximate dimer-atom-atom structure are studied using momentum-space integral equations for the four-particle transition operators. For a given Efimov trimer the universal properties of the lowest associated tetramer are determined. The impact of this tetramer on the atom-trimer and dimer-dimer collisions is analyzed. The reliability of the three-body dimer-atom-atom model is studied.

  18. Universal bosonic tetramers of dimer-atom-atom structure

    E-Print Network [OSTI]

    Deltuva, A

    2012-01-01T23:59:59.000Z

    Unstable four-boson states having an approximate dimer-atom-atom structure are studied using momentum-space integral equations for the four-particle transition operators. For a given Efimov trimer the universal properties of the lowest associated tetramer are determined. The impact of this tetramer on the atom-trimer and dimer-dimer collisions is analyzed. The reliability of the three-body dimer-atom-atom model is studied.

  19. Nano Positioning of Single Atoms in a Micro Cavity

    E-Print Network [OSTI]

    Stefan Nussmann; Markus Hijlkema; Bernhard Weber; Felix Rohde; Gerhard Rempe; Axel Kuhn

    2005-06-10T23:59:59.000Z

    The coupling of individual atoms to a high-finesse optical cavity is precisely controlled and adjusted using a standing-wave dipole-force trap, a challenge for strong atom-cavity coupling. Ultracold Rubidium atoms are first loaded into potential minima of the dipole trap in the center of the cavity. Then we use the trap as a conveyor belt that we set into motion perpendicular to the cavity axis. This allows us to repetitively move atoms out of and back into the cavity mode with a repositioning precision of 135 nm. This makes possible to either selectively address one atom of a string of atoms by the cavity, or to simultaneously couple two precisely separated atoms to a higher mode of the cavity.

  20. Atomic Force Microscope

    SciTech Connect (OSTI)

    Day, R.D.; Russell, P.E.

    1988-12-01T23:59:59.000Z

    The Atomic Force Microscope (AFM) is a recently developed instrument that has achieved atomic resolution imaging of both conducting and non- conducting surfaces. Because the AFM is in the early stages of development, and because of the difficulty of building the instrument, it is currently in use in fewer than ten laboratories worldwide. It promises to be a valuable tool for obtaining information about engineering surfaces and aiding the .study of precision fabrication processes. This paper gives an overview of AFM technology and presents plans to build an instrument designed to look at engineering surfaces.

  1. Iowa Powder Atomization Technologies

    ScienceCinema (OSTI)

    None

    2013-03-01T23:59:59.000Z

    The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

  2. Iowa Powder Atomization Technologies

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    The same atomization effect seen in a fuel injector is being applied to titanium metal resulting in fine titanium powders that are less than half the width of a human hair. Titanium melts above 3,000°F and is highly corrosive therefore requiring specialized containers. The liquid titanium is poured through an Ames Laboratory - USDOE patented tube which is intended to increase the energy efficiency of the atomization process, which has the ability to dramatically decrease the cost of fine titanium powders. This novel process could open markets for green manufacturing of titanium components from jet engines to biomedical implants.

  3. Elements & Compounds Atoms (Elements)

    E-Print Network [OSTI]

    Frey, Terry

    #12;Elements & Compounds #12;Atoms (Elements) Molecules (Compounds) Cells Elements & Compounds #12 #12;First shell Second shell Third shell Hydrogen 1H Lithium 3Li Sodium 11Na Beryllium 4Be Magnesium energy Higher energy (a) A ball bouncing down a flight of stairs provides an analogy for energy levels

  4. Atom chip apparatus for experiments with ultracold rubidium and potassium gases

    SciTech Connect (OSTI)

    Ivory, M. K.; Ziltz, A. R.; Fancher, C. T.; Pyle, A. J.; Sensharma, A.; Chase, B.; Field, J. P.; Garcia, A.; Aubin, S., E-mail: saaubi@wm.edu [Department of Physics, College of William and Mary, Williamsburg, Virginia 23187 (United States); Jervis, D. [Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)] [Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7 (Canada)

    2014-04-15T23:59:59.000Z

    We present a dual chamber atom chip apparatus for generating ultracold {sup 87}Rb and {sup 39}K atomic gases. The apparatus produces quasi-pure Bose-Einstein condensates of 10{sup 4} {sup 87}Rb atoms in an atom chip trap that features a dimple and good optical access. We have also demonstrated production of ultracold {sup 39}K and subsequent loading into the chip trap. We describe the details of the dual chamber vacuum system, the cooling lasers, the magnetic trap, the multicoil magnetic transport system, the atom chip, and two optical dipole traps. Due in part to the use of light-induced atom desorption, the laser cooling chamber features a sufficiently good vacuum to also support optical dipole trap-based experiments. The apparatus is well suited for studies of atom-surface forces, quantum pumping and transport experiments, atom interferometry, novel chip-based traps, and studies of one-dimensional many-body systems.

  5. Atom-by-atom nucleation and growth of graphene nanopores

    E-Print Network [OSTI]

    Golovchenko, Jene A.

    Atom-by-atom nucleation and growth of graphene nanopores Christopher J. Russoa,b and J. A February 17, 2012 (received for review December 9, 2011) Graphene is an ideal thin membrane substrate structures in graphene with atomic preci- sion. It consists of inducing defect nucleation centers with ener

  6. Atomic phenomena in dense plasmas

    SciTech Connect (OSTI)

    Weisheit, J.C.

    1981-03-01T23:59:59.000Z

    The following chapters are included: (1) the plasma environment, (2) perturbations of atomic structure, (3) perturbations of atomic collisions, (4) formation of spectral lines, and (5) dielectronic recombination. (MOW)

  7. atoms: Topics by E-print Network

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

    with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory...

  8. A microfabricated atomic clock

    SciTech Connect (OSTI)

    Knappe, Svenja; Shah, Vishal; Schwindt, Peter D.D.; Hollberg, Leo; Kitching, John; Liew, Li-Anne; Moreland, John [Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305-3328 (United States); Electromagnetics Division, National Institute of Standards and Technology, Boulder, Colorado 80305-3328 (United States)

    2004-08-30T23:59:59.000Z

    Fabrication techniques usually applied to microelectromechanical systems (MEMS) are used to reduce the size and operating power of the core physics assembly of an atomic clock. With a volume of 9.5 mm{sup 3}, a fractional frequency instability of 2.5x10{sup -10} at 1 s of integration, and dissipating less than 75 mW of power, the device has the potential to bring atomically precise timing to hand-held, battery-operated devices. In addition, the design and fabrication process allows for wafer-level assembly of the structures, enabling low-cost mass-production of thousands of identical units with the same process sequence, and easy integration with other electronics.

  9. Delay in Atomic Photoionization

    SciTech Connect (OSTI)

    Kheifets, A. S. [Research School of Physical Sciences, Australian National University, Canberra ACT 0200 (Australia); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106-4030 (United States); Ivanov, I. A. [Research School of Physical Sciences, Australian National University, Canberra ACT 0200 (Australia)

    2010-12-03T23:59:59.000Z

    We analyze the time delay between emission of photoelectrons from the outer valence ns and np subshells in noble gas atoms following absorption of an attosecond extreme ultraviolet pulse. Various processes such as elastic scattering of the photoelectron on the parent ion and many-electron correlation affect the apparent 'time zero' when the photoelectron leaves the atom. This qualitatively explains the time delay between photoemission from the 2s and 2p subshells of Ne as determined experimentally by attosecond streaking [Science 328, 1658 (2010)]. However, with our extensive numerical modeling, we were only able to account for less than half of the measured time delay of 21{+-}5 as. We argue that the extreme ultraviolet pulse alone cannot produce such a large time delay and it is the streaking IR field that is most likely responsible for this effect.

  10. Optics and interferometry with atoms and molecules

    E-Print Network [OSTI]

    Cronin, Alexander D.

    Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic ...

  11. Design of a dual species atom interferometer for space

    E-Print Network [OSTI]

    Schuldt, Thilo; Krutzik, Markus; Bote, Lluis Gesa; Gaaloul, Naceur; Hartwig, Jonas; Ahlers, Holger; Herr, Waldemar; Posso-Trujillo, Katerine; Rudolph, Jan; Seidel, Stephan; Wendrich, Thijs; Ertmer, Wolfgang; Herrmann, Sven; Kubelka-Lange, André; Milke, Alexander; Rievers, Benny; Rocco, Emanuele; Hinton, Andrew; Bongs, Kai; Oswald, Markus; Franz, Matthias; Hauth, Matthias; Peters, Achim; Bawamia, Ahmad; Wicht, Andreas; Battelier, Baptiste; Bertoldi, Andrea; Bouyer, Philippe; Landragin, Arnaud; Massonnet, Didier; Lévèque, Thomas; Wenzlawski, Andre; Hellmig, Ortwin; Windpassinger, Patrick; Sengstock, Klaus; von Klitzing, Wolf; Chaloner, Chris; Summers, David; Ireland, Philip; Mateos, Ignacio; Sopuerta, Carlos F; Sorrentino, Fiodor; Tino, Guglielmo M; Williams, Michael; Trenkel, Christian; Gerardi, Domenico; Chwalla, Michael; Burkhardt, Johannes; Johann, Ulrich; Heske, Astrid; Wille, Eric; Gehler, Martin; Cacciapuoti, Luigi; Gürlebeck, Norman; Braxmaier, Claus; Rasel, Ernst

    2014-01-01T23:59:59.000Z

    Atom interferometers have a multitude of proposed applications in space including precise measurements of the Earth's gravitational field, in navigation & ranging, and in fundamental physics such as tests of the weak equivalence principle (WEP) and gravitational wave detection. While atom interferometers are realized routinely in ground-based laboratories, current efforts aim at the development of a space compatible design optimized with respect to dimensions, weight, power consumption, mechanical robustness and radiation hardness. In this paper, we present a design of a high-sensitivity differential dual species $^{85}$Rb/$^{87}$Rb atom interferometer for space, including physics package, laser system, electronics and software. The physics package comprises the atom source consisting of dispensers and a 2D magneto-optical trap (MOT), the science chamber with a 3D-MOT, a magnetic trap based on an atom chip and an optical dipole trap (ODT) used for Bose-Einstein condensate (BEC) creation and interferometry...

  12. Atomic Collapse Observed

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumni AlumniFederalAshley BoyleAn overhead viewAtom-split it

  13. Feedback Cooling of a Single Neutral Atom

    E-Print Network [OSTI]

    Markus Koch; Christian Sames; Alexander Kubanek; Matthias Apel; Maximilian Balbach; Alexei Ourjoumtsev; Pepijn W. H. Pinkse; Gerhard Rempe

    2010-10-15T23:59:59.000Z

    We demonstrate feedback cooling of the motion of a single rubidium atom trapped in a high-finesse optical resonator to a temperature of about 160 \\mu K. Time-dependent transmission and intensity-correlation measurements prove the reduction of the atomic position uncertainty. The feedback increases the 1/e storage time into the one second regime, 30 times longer than without feedback. Feedback cooling therefore rivals state-of-the-art laser cooling, but with the advantages that it requires less optical access and exhibits less optical pumping.

  14. atomic ions: Topics by E-print Network

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

    Lothar Ratschbacher; Carlo Sias; Michael Khl 2010-08-17 4 Micromotion in trapped atom-ion systems Quantum Physics (arXiv) Summary: We examine the validity of the harmonic...

  15. Towards a quantum gas microscope for fermionic atoms

    E-Print Network [OSTI]

    Ramasesh, Vinay (Vinay V.)

    2012-01-01T23:59:59.000Z

    This thesis reports the achievement of a two-species apparatus for use in an upcoming experiment with fermionic ultracold atomic gases. First, we describe the construction of a laser system capable of cooling and trapping ...

  16. atomic interaction networks: Topics by E-print Network

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

    or lambda configuration E. S. Guerra; C. R. Carvalho 2005-01-15 13 Trapped atomic condensates with anisotropic interactions Quantum Physics (arXiv) Summary: We study the ground...

  17. atomic oxygen interactions: Topics by E-print Network

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

    or lambda configuration E. S. Guerra; C. R. Carvalho 2005-01-15 16 Trapped atomic condensates with anisotropic interactions Quantum Physics (arXiv) Summary: We study the ground...

  18. atomic oxygen interaction: Topics by E-print Network

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

    or lambda configuration E. S. Guerra; C. R. Carvalho 2005-01-15 16 Trapped atomic condensates with anisotropic interactions Quantum Physics (arXiv) Summary: We study the ground...

  19. Realization of Bose-Einstein condensation with Lithium-7 atoms

    E-Print Network [OSTI]

    Yu, Yichao

    2014-01-01T23:59:59.000Z

    This thesis presents our work on developing and improving the techniques of trapping and cooling an ultra-cold cloud of Lithium-7 atoms and the realization of the Bose- Einstein condensate as a first step to study quantum ...

  20. Atomic Energy Commission Takes Over Responsibility for all Atomic...

    National Nuclear Security Administration (NNSA)

    Takes Over Responsibility for all Atomic Energy Programs | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile...

  1. Optical quantum swapping in a coherent atomic medium

    E-Print Network [OSTI]

    Aurelien Dantan

    2011-10-03T23:59:59.000Z

    We propose to realize a passive optical quantum swapping device which allows for the exchange of the quantum fluctuations of two bright optical fields interacting with a coherent atomic medium in an optical cavity. The device is based on a quantum interference process between the fields within the cavity bandwidth arising from coherent population trapping in the atomic medium.

  2. Mobile and remote inertial sensing with atom interferometers

    E-Print Network [OSTI]

    Boyer, Edmond

    Mobile and remote inertial sensing with atom interferometers B. Barrett, P.-A. Gominet, E. Cantin for equivalence principle tests. We also discuss fu- ture applications of this technology, such as remote sensing on laser-cooling and trapping neutral atoms [6, 7, 8, 9, 10] which eventually led to two nobel prizes

  3. Quantum transport in ultracold atoms

    E-Print Network [OSTI]

    Chih-Chun Chien; Sebastiano Peotta; Massimiliano Di Ventra

    2015-04-11T23:59:59.000Z

    Ultracold atoms confined by engineered magnetic or optical potentials are ideal systems for studying phenomena otherwise difficult to realize or probe in the solid state because their atomic interaction strength, number of species, density, and geometry can be independently controlled. This review focuses on quantum transport phenomena in atomic gases that mirror and oftentimes either better elucidate or show fundamental differences with those observed in mesoscopic and nanoscopic systems. We discuss significant progress in performing transport experiments in atomic gases, contrast similarities and differences between transport in cold atoms and in condensed matter systems, and survey inspiring theoretical predictions that are difficult to verify in conventional setups. These results further demonstrate the versatility offered by atomic systems in the study of nonequilibrium phenomena and their promise for novel applications.

  4. Atom interferometry in an optical cavity

    E-Print Network [OSTI]

    Paul Hamilton; Matt Jaffe; Justin M. Brown; Lothar Maisenbacher; Brian Estey; Holger Müller

    2014-09-25T23:59:59.000Z

    We propose and demonstrate a new scheme for atom interferometry, using light pulses inside an optical cavity as matter wave beamsplitters. The cavity provides power enhancement, spatial filtering, and a precise beam geometry, enabling new techniques such as low power beamsplitters ($modest power, or new self-aligned interferometer geometries utilizing the transverse modes of the optical cavity. As a first demonstration, we obtain Ramsey-Raman fringes with $>75\\%$ contrast and measure the acceleration due to gravity, $\\mathit{g}$, to $60 \\mathrm{\\mu \\mathit{g} / \\sqrt{Hz}}$ resolution in a Mach-Zehnder geometry. We use $>10^7$ cesium atoms in the compact mode volume ($600 \\mathrm{\\mu m}$ $1/e^2$ waist) of the cavity and show trapping of atoms in higher transverse modes. This work paves the way toward compact, high sensitivity, multi-axis interferometry.

  5. Coherent Atom Optics with fast metastable rare gas atoms

    SciTech Connect (OSTI)

    Grucker, J.; Baudon, J.; Karam, J.-C.; Perales, F.; Vassilev, G.; Ducloy, M. [Laboratoire de Physique des Lasers, Universite Paris 13, Avenue J.B. Clement, 93430-Villetaneuse (France); Bocvarski, V. [Institute of Physics, Pregrevica 118, 11080 - Belgrade-Zemun (Serbia and Montenegro)

    2006-12-01T23:59:59.000Z

    Coherent atom optics experiments making use of an ultra-narrow beam of fast metastable atoms generated by metastability exchange are reported. The transverse coherence of the beam (coherence radius of 1.7 {mu}m for He*, 1.2 {mu}m for Ne*, 0.87 {mu}m for Ar*) is demonstrated via the atomic diffraction by a non-magnetic 2{mu}m-period reflection grating. The combination of the non-scalar van der Waals (vdW) interaction with the Zeeman interaction generated by a static magnetic field gives rise to ''vdW-Zeeman'' transitions among Zeeman sub-levels. Exo-energetic transitions of this type are observed with Ne*(3P2) atoms traversing a copper micro-slit grating. They can be used as a tunable beam splitter in an inelastic Fresnel bi-prism atom interferometer.

  6. Studies of atomic hydrogen beam sources

    E-Print Network [OSTI]

    Schafer, Todd William

    1989-01-01T23:59:59.000Z

    with the Penning ion trap and data acquisition system, and to Mr. Shigu Tu for assisting him with the RF ion trap system and collection of data. TABLE OF CONTENTS CHAPTER Page I INTRODUCTION II BACKGROUND . II. 1 Atomic Hydrogen Production II. 2 Polarized..., and hexapole magnet present. However, testing was done on the Penning system with both discharge tubes. Atomrc hydrogen was produced in the source system by a rf discharge (30 MHz g: 73 MHz for the new and old discharge tubes, respectively) through a pyrex...

  7. Moller Polarimetry with Atomic Hydrogen Targets

    SciTech Connect (OSTI)

    Chudakov, Eugene [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Luppov, V. [University of Michigan Spin Physics Center, Ann Arbor, MI (United States)

    2012-06-01T23:59:59.000Z

    A proposal to use polarized atomic hydrogen gas as the target for electron beam polarimetry based on the Moller scattering is described. Such a gas, stored in an ultra-cold magnetic trap, would provide a target of practically 100\\% polarized electrons. It is conceivable to reach a $\\sim$0.3\\% systematic accuracy of the beam polarimetry with such a target. Feasibility studies for the CEBAF electron beam have been performed.

  8. Transport of atom packets in a train of Ioffe-Pritchard traps T. Lahaye, G. Reinaudi, Z. Wang, A. Couvert, and D. Gury-Odelin

    E-Print Network [OSTI]

    Guéry-Odelin, David

    cooling techniques, of a magnetically guided atomic beam on which evaporative cooling can then be applied Received 11 May 2006; published 28 September 2006 We demonstrate transport and evaporative cooling.1103/PhysRevA.74.033622 PACS number s : 03.75.Pp, 32.80.Pj The combination of laser cooling and evaporative

  9. Loading atom lasers by collectivity-enhanced optical pumping

    SciTech Connect (OSTI)

    Macovei, Mihai A.; Evers, Joerg [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)

    2010-01-15T23:59:59.000Z

    The effect of collectivity on the loading of an atom laser via optical pumping is discussed. In our model, atoms in a beam are laser-excited and subsequently spontaneously decay into a trapping state. We consider the case of sufficiently high particle density in the beam such that the spontaneous emission is modified by the particle interaction. We show that the collective effects lead to a better population of the trapping state over a wide range of system parameters, and that the second-order correlation function of the atoms can be controlled by the applied laser field.

  10. Magnetic-film atom chip with 10 $?$m period lattices of microtraps for quantum information science with Rydberg atoms

    E-Print Network [OSTI]

    V. Y. F. Leung; D. R. M. Pijn; H. Schlatter; L. Torralbo-Campo; A. La Rooij; G. B. Mulder; J. Naber; M. L. Soudijn; A. Tauschinsky; C. Abarbanel; B. Hadad; E. Golan; R. Folman; R. J. C. Spreeuw

    2014-07-01T23:59:59.000Z

    We describe the fabrication and construction of a setup for creating lattices of magnetic microtraps for ultracold atoms on an atom chip. The lattice is defined by lithographic patterning of a permanent magnetic film. Patterned magnetic-film atom chips enable a large variety of trapping geometries over a wide range of length scales. We demonstrate an atom chip with a lattice constant of 10 $\\mu$m, suitable for experiments in quantum information science employing the interaction between atoms in highly-excited Rydberg energy levels. The active trapping region contains lattice regions with square and hexagonal symmetry, with the two regions joined at an interface. A structure of macroscopic wires, cut out of a silver foil, was mounted under the atom chip in order to load ultracold $^{87}$Rb atoms into the microtraps. We demonstrate loading of atoms into the square and hexagonal lattice sections simultaneously and show resolved imaging of individual lattice sites. Magnetic-film lattices on atom chips provide a versatile platform for experiments with ultracold atoms, in particular for quantum information science and quantum simulation.

  11. Magnetic-film atom chip with 10 ?m period lattices of microtraps for quantum information science with Rydberg atoms

    SciTech Connect (OSTI)

    Leung, V. Y. F. [Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, PO Box 94485, 1090 GL Amsterdam (Netherlands) [Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, PO Box 94485, 1090 GL Amsterdam (Netherlands); Complex Photonic Systems (COPS), MESA Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede (Netherlands); Pijn, D. R. M.; Schlatter, H.; Torralbo-Campo, L.; La Rooij, A. L.; Mulder, G. B.; Naber, J.; Soudijn, M. L.; Tauschinsky, A.; Spreeuw, R. J. C., E-mail: r.j.c.spreeuw@uva.nl [Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, PO Box 94485, 1090 GL Amsterdam (Netherlands)] [Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, PO Box 94485, 1090 GL Amsterdam (Netherlands); Abarbanel, C.; Hadad, B.; Golan, E. [Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er Sheva 84105 (Israel)] [Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er Sheva 84105 (Israel); Folman, R. [Department of Physics and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er Sheva 84105 (Israel)] [Department of Physics and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Be'er Sheva 84105 (Israel)

    2014-05-15T23:59:59.000Z

    We describe the fabrication and construction of a setup for creating lattices of magnetic microtraps for ultracold atoms on an atom chip. The lattice is defined by lithographic patterning of a permanent magnetic film. Patterned magnetic-film atom chips enable a large variety of trapping geometries over a wide range of length scales. We demonstrate an atom chip with a lattice constant of 10 ?m, suitable for experiments in quantum information science employing the interaction between atoms in highly excited Rydberg energy levels. The active trapping region contains lattice regions with square and hexagonal symmetry, with the two regions joined at an interface. A structure of macroscopic wires, cutout of a silver foil, was mounted under the atom chip in order to load ultracold {sup 87}Rb atoms into the microtraps. We demonstrate loading of atoms into the square and hexagonal lattice sections simultaneously and show resolved imaging of individual lattice sites. Magnetic-film lattices on atom chips provide a versatile platform for experiments with ultracold atoms, in particular for quantum information science and quantum simulation.

  12. Bogoliubov theory and bosonic atoms

    E-Print Network [OSTI]

    Phan Thanh Nam

    2011-09-13T23:59:59.000Z

    We formulate the Bogoliubov variational principle in a mathematical framework similar to the generalized Hartree-Fock theory. Then we analyze the Bogoliubov theory for bosonic atoms in details. We discuss heuristically why the Bogoliubov energy should give the first correction to the leading energy of large bosonic atoms.

  13. In-situ control system for atomization

    DOE Patents [OSTI]

    Anderson, I.E.; Figliola, R.S.; Terpstra, R.L.

    1995-06-13T23:59:59.000Z

    Melt atomizing apparatus comprising a melt supply orifice for supplying the melt for atomization and gas supply orifices proximate the melt supply orifice for supplying atomizing gas to atomize the melt as an atomization spray is disclosed. The apparatus includes a sensor, such as an optical and/or audio sensor, for providing atomization spray data, and a control unit responsive to the sensed atomization spray data for controlling at least one of the atomizing gas pressure and an actuator to adjust the relative position of the gas supply orifice and melt supply in a manner to achieve a desired atomization spray. 3 figs.

  14. Spectral Emission of Moving Atom

    E-Print Network [OSTI]

    J. X. Zheng-Johansson

    2008-03-17T23:59:59.000Z

    A renewed analysis of the H.E. Ives and G.R. Stilwell's experiment on moving hydrogen canal rays (J. Opt. Soc. Am., 1938, v.28, 215) concludes that the spectral emission of a moving atom exhibits always a redshift which informs not the direction of the atom's motion. The conclusion is also evident from a simple energy relation: atomic spectral radiation is emitted as an orbiting electron consumes a portion of its internal energy on transiting to a lower-energy state which however has in a moving atom an additional energy gain; this results in a redshift in the emission frequency. Based on auxiliary experimental information and a scheme for de Broglie particle formation, we give a vigorous elucidation of the mechanism for deceleration radiation of atomic electron; the corresponding prediction of the redshift is in complete agreement with the Ives and Stilwell's experimental formula.

  15. Supersonic coal water slurry fuel atomizer

    DOE Patents [OSTI]

    Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA); Balsavich, John (Foxborough, MA)

    1991-01-01T23:59:59.000Z

    A supersonic coal water slurry atomizer utilizing supersonic gas velocities to atomize coal water slurry is provided wherein atomization occurs externally of the atomizer. The atomizer has a central tube defining a coal water slurry passageway surrounded by an annular sleeve defining an annular passageway for gas. A converging/diverging section is provided for accelerating gas in the annular passageway to supersonic velocities.

  16. Remote generation of entanglement for individual atoms via optical fibers

    E-Print Network [OSTI]

    Y. Q. Guo; H. Y. Zhong; Y. H. Zhang; H. S. Song

    2008-05-29T23:59:59.000Z

    The generation of atomic entanglement is discussed in a system that atoms are trapped in separate cavities which are connected via optical fibers. Two distant atoms can be projected to Bell-state by synchronized turning off the local laser fields and then performing a single quantum measurement by a distant controller. The distinct advantage of this scheme is that it works in a regime that $\\Delta\\approx\\kappa\\gg g$, which makes the scheme insensitive to cavity strong leakage. Moreover, the fidelity is not affected by atomic spontaneous emission.

  17. atomic bose-einstein condensate: Topics by E-print Network

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

    by periodically replenishing a condensate held in an optical dipole trap with new condensates delivered using optical tweezers. The source contained more than 1 106 atoms at all...

  18. Detection of transient fluorine atoms

    SciTech Connect (OSTI)

    Loge, G.W.; Nereson, N.; Fry, H.A.

    1986-01-01T23:59:59.000Z

    A KrF eximer laser with a fluence of 50 mJ/cm/sup 2/ was used to photolyze either uranium hexafluoride or molecular fluorine, yielding a transient number density of fluorine atoms. The rise and decay of the atomic fluorine density was observed by transient absorption of a 25-..mu..m Pb-salt diode laser. To prevent the diode laser wavelength from drifting out of resonance with the atomic fluorine line, part of the beam was split off and sent through a microwave discharge fluorine atom cell. This allowed a wavelength modulation-feedback technique to be used to lock the diode laser wavelength onto the atomic line. The remaining diode laser beam was made collinear with the eximer laser beam using a LiF window with a 45/sup 0/ angle of incidence to reflect the infrared beam while transmitting most of the uv beam. Using this setup along with a transient digitizer to average between 100 and 200 transient absorption profiles, fluorine atom number densities on the order of 10/sup 14/ cm/sup -3/ in a 1.7 m pathlength were detected. The signals observed were about a factor of two less than expected from known photolysis and atomic fluorine absorption cross-sections. 2 refs., 4 figs.

  19. Anticipating the atom: popular perceptions of atomic power before Hiroshima

    E-Print Network [OSTI]

    d'Emal, Jacques-Andre Christian

    1994-01-01T23:59:59.000Z

    Before Hiroshima made the Bomb an object of popular concern, possible implications and applications of atomic physics had been discussed in the public forum. The new science of X-rays and radium promised the possibilities of unlimited energy...

  20. atomization atomic absorption: Topics by E-print Network

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

    cells to modern observations of dust clouds in stellar nebulas and Bose-Einstein condensates. Here we show the first absorption imaging of a single atom isolated in vacuum. The...

  1. Chemical factors influencing selenium atomization

    E-Print Network [OSTI]

    Buren, Mary Sue

    1980-01-01T23:59:59.000Z

    Atomization. (August 1980) Mary Sue Buren, B, S. , Angelo State University Chairman of Advisory Comm1ttee: Dr. Thomas M. Vickrey Selenium in an acid1c matrix was analyzed using graphite furnace atom1c absorption with Zeeman-effect background correct1on.... Nickel(II} and lanthanum( III) were introduced as matrix modifiers to determine their effect on interferences 1n selenium atom1zation. In add1tion to matr1x mod1ficat1on, surface coating the graphite furnace with z1rconium and tantalum salts was also...

  2. Chemical factors influencing selenium atomization 

    E-Print Network [OSTI]

    Buren, Mary Sue

    1980-01-01T23:59:59.000Z

    Atomization. (August 1980) Mary Sue Buren, B, S. , Angelo State University Chairman of Advisory Comm1ttee: Dr. Thomas M. Vickrey Selenium in an acid1c matrix was analyzed using graphite furnace atom1c absorption with Zeeman-effect background correct1on.... Nickel(II} and lanthanum( III) were introduced as matrix modifiers to determine their effect on interferences 1n selenium atom1zation. In add1tion to matr1x mod1ficat1on, surface coating the graphite furnace with z1rconium and tantalum salts was also...

  3. Heterogeneous Catalysis on Atomically Dispersed Supported Metals...

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

    Catalysis on Atomically Dispersed Supported Metals: CO2 Reduction on Multifunctional Pd Catalysts. Heterogeneous Catalysis on Atomically Dispersed Supported Metals: CO2 Reduction...

  4. Imaging atoms in 3-D

    ScienceCinema (OSTI)

    Ercius, Peter

    2014-06-27T23:59:59.000Z

    Berkeley Lab's Peter Ercius discusses "Imaging atoms in 3-D" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas

  5. Imaging atoms in 3-D

    SciTech Connect (OSTI)

    Ercius, Peter

    2013-10-31T23:59:59.000Z

    Berkeley Lab's Peter Ercius discusses "Imaging atoms in 3-D" in this Oct. 28, 2013 talk, which is part of a Science at the Theater event entitled Eight Big Ideas

  6. Absorption properties of identical atoms

    E-Print Network [OSTI]

    Pedro Sancho

    2013-07-31T23:59:59.000Z

    Emission rates and other optical properties of multiparticle systems in collective and entangled states differ from those in product ones. We show the existence of similar effects in the absorption probabilities for (anti)symmetrized states of two identical atoms. The effects strongly depend on the overlapping between the atoms and differ for bosons and fermions. We propose a viable experimental verification of these ideas.

  7. Universal 1+2-body bound states in planar atomic wave guides Ludovic Pricoupenko(1)

    E-Print Network [OSTI]

    physics open the possi- bility of trapping and cooling atomic mixtures composed of different atomic species [1­4] in quasi two-dimensional (quasi-2D) geometries [5, 6]. These dramatic progress open exciting ratio. Motivated by these recent progress, we consider in this paper mixtures of two atomic species

  8. Bose-Einstein condensation in dilute atomic gases1 Hans-Joachim Miesner and Wolfgang Ketterle

    E-Print Network [OSTI]

    -8] contained a more complete account on the cooling and trapping techniques and described the progress during and observe nanokelvin samples of atoms. Keywords: Bose-Einstein condensation, optical cooling and trapping atoms by two to three orders of magnitude. The observation of BEC in such systems [1-3] has created

  9. Probabilistic quantum gates between remote atoms through interference of optical frequency qubits

    E-Print Network [OSTI]

    Madsen, Martin John

    Probabilistic quantum gates between remote atoms through interference of optical frequency qubits L gates on remote trapped atom qubits through interference of optical frequency qubits. The method does be localized well under the Lamb-Dicke limit through laser cooling in a strong trap, the elimination

  10. Long Range Interactions With Laser Cooled Neutral Atoms

    SciTech Connect (OSTI)

    Gattobigio, Giovanni Luca [Institut Non Lineaire de Nice, Universite de Nice-Sophia-Antipolis, CNRS UMR 661, 1361, route des Lucioles 06560 Valbonne France (France); Dipartimento di Fisica dell'Universita di Ferrara, 44100 Ferrara (Italy); Michaud, Franck; Labeyrie, Guillaume; Kaiser, Robin [Institut Non Lineaire de Nice, Universite de Nice-Sophia-Antipolis, CNRS UMR 661, 1361, route des Lucioles 06560 Valbonne (France); Loureiro, Jorge; Mendonca, Jose Tito; Tercas, Hugo [Instituto Superior Tecnico, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal); Pohl, Thomas [ITAMP, 60 Garden Street, Cambridge, MA 02138 (United States)

    2008-09-07T23:59:59.000Z

    Multiple scattering of light in a trap of laser cooled neutral atoms leads to repulsion forces between the atoms. The corresponding interactions have long range behavior in 1/r{sup 2} and are thus similar to Coulomb interaction in an one component confined plasma. Consequences of these interactions will be described in this paper, including the limitation of the spatial density one can obtain in such systems and self-sustained oscillations of the cloud.

  11. Atomic Cascade in Muonic and Hadronic Hydrogen Atoms

    E-Print Network [OSTI]

    T. S. Jensen; V. P. Popov; V. N. Pomerantsev

    2007-12-18T23:59:59.000Z

    The atomic cascade in $\\mu^- p$ and $\\pi^- p$ atoms has been studied with the improved version of the extended cascade model in which new quantum mechanical calculations of the differential and integral cross sections of the elastic scattering, Stark transitions and Coulomb de-excitation have been included for the principal quantum number values $n\\le 8$ and the relative energies $E \\ge 0.01$ eV. The $X$-ray yields and kinetic energy distributions are compared with the experimental data.

  12. Quantum Electrodynamics of Atomic Resonances

    E-Print Network [OSTI]

    Miguel Ballesteros; Jérémy Faupin; Jürg Fröhlich; Baptiste Schubnel

    2015-03-09T23:59:59.000Z

    A simple model of an atom interacting with the quantized electromagnetic field is studied. The atom has a finite mass $m$, finitely many excited states and an electric dipole moment, $\\vec{d}_0 = -\\lambda_{0} \\vec{d}$, where $\\| d^{i}\\| = 1,$ $ i=1,2,3,$ and $\\lambda_0$ is proportional to the elementary electric charge. The interaction of the atom with the radiation field is described with the help of the Ritz Hamiltonian, $-\\vec{d}_0\\cdot \\vec{E}$, where $\\vec{E}$ is the electric field, cut off at large frequencies. A mathematical study of the Lamb shift, the decay channels and the life times of the excited states of the atom is presented. It is rigorously proven that these quantities are analytic functions of the momentum $\\vec{p}$ of the atom and of the coupling constant $\\lambda_0$, provided $|\\vec{p}| < mc$ and $| \\Im\\vec{p} |$ and $| \\lambda_{0} |$ are sufficiently small. The proof relies on a somewhat novel inductive construction involving a sequence of `smooth Feshbach-Schur maps' applied to a complex dilatation of the original Hamiltonian, which yields an algorithm for the calculation of resonance energies that converges super-exponentially fast.

  13. Stationary light in cold atomic gases

    E-Print Network [OSTI]

    Gor Nikoghosyan; Michael Fleischhauer

    2009-09-16T23:59:59.000Z

    We discuss stationary light created by a pair of counter-propagating control fields in Lambda-type atomic gases with electromagnetically induced transparency for the case of negligible Doppler broadening. In this case the secular approximation used in the discussion of stationary light in hot vapors is no longer valid. We discuss the quality of the effective light-trapping system and show that in contrast to previous claims it is finite even for vanishing ground-state dephasing. The dynamics of the photon loss is in general non exponential and can be faster or slower than in hot gases.

  14. Degeneracy Breaking of Hydrogen Atom

    E-Print Network [OSTI]

    Agung Trisetyarso; Pantur Silaban

    2014-11-21T23:59:59.000Z

    The three dimensional rotation group, SO(3), is a symmetry group of the normal hydrogen atom. Each reducible representation of this group can be associated with a degenerate energy level. If this atom is placed in an external magnetic field, the interaction between the orbital magnetic moment with this field will lead to a symmetry breaking where the symmetry group of the atom is a new group distinct from the SO(3) group. This phenomenon describes the normal Zeeman effect, where a degenerate energy level splits into several new energy levels. It is explicitly shown that each of the new energy levels can be associated with an irreducible representation of the new symmetry group.

  15. Atomizing, continuous, water monitoring module

    DOE Patents [OSTI]

    Thompson, Cyril V. (Knoxville, TN); Wise, Marcus B. (Kingston, TN)

    1997-01-01T23:59:59.000Z

    A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid.

  16. Atomizing, continuous, water monitoring module

    DOE Patents [OSTI]

    Thompson, C.V.; Wise, M.B.

    1997-07-08T23:59:59.000Z

    A system for continuously analyzing volatile constituents of a liquid is described. The system contains a pump for continuously pumping the liquid to be tested at a predetermined flow rate into an extracting container through a liquid directing tube having an orifice at one end and positioned to direct the liquid into the extracting container at a flow rate sufficient to atomize the liquid within the extracting container. A continuous supply of helium carrier gas at a predetermined flow rate is directed through a tube into the extracting container and co-mingled with the atomized liquid to extract the volatile constituents contained within the atomized liquid. The helium containing the extracted volatile constituents flows out of the extracting container into a mass spectrometer for an analysis of the volatile constituents of the liquid. 3 figs.

  17. Ultracold atoms in a cavity mediated double-well system

    E-Print Network [OSTI]

    Jonas Larson; Jani-Petri Martikainen

    2010-09-13T23:59:59.000Z

    We study ground-state properties and dynamics of a dilute ultracold atomic gas in a double well potential. The Gaussian barrier separating the two wells derives from the interaction between the atoms and a quantized field of a driven Fabry-Perot cavity. Due to intrinsic atom-field nonlinearity, several novel phenomena arise being the focus of this work. For the ground state, there is a critical pumping amplitude in which the atoms self-organize and the intra cavity field amplitude drastically increases. In the dynamical analysis, we show that the Josephson oscillations depend strongly on the atomic density and may be greatly suppressed within certain regimes, reminiscent of self-trapping of Bose-Einstein condensates in double-well setups. This pseudo self-trapping effect is studied within a mean-field treatment valid for large atom numbers. For small numbers of atoms, we consider the analogous many-body problem and demonstrate a collapse-revival structure in the Josephson oscillations.

  18. Cold atoms as a coolant for levitated optomechanical systems

    E-Print Network [OSTI]

    Gambhir Ranjit; Cris Montoya; Andrew A. Geraci

    2014-12-17T23:59:59.000Z

    Optically trapped dielectric objects are well suited for reaching the quantum regime of their center of mass motion in an ultra-high vacuum environment. We show that ground state cooling of an optically trapped nanosphere is achievable when starting at room temperature, by sympathetic cooling of a cold atomic gas optically coupled to the nanoparticle. Unlike cavity cooling in the resolved sideband limit, this system requires only a modest cavity finesse and it allows the cooling to be turned off, permitting subsequent observation of strongly-coupled dynamics between the atoms and sphere. Nanospheres cooled to their quantum ground state could have applications in quantum information science or in precision sensing.

  19. Nanoplasmonic Lattices for Ultracold atoms

    E-Print Network [OSTI]

    M. Gullans; T. Tiecke; D. E. Chang; J. Feist; J. D. Thompson; J. I. Cirac; P. Zoller; M. D. Lukin

    2014-07-25T23:59:59.000Z

    We propose to use sub-wavelength confinement of light associated with the near field of plasmonic systems to create nanoscale optical lattices for ultracold atoms. Our approach combines the unique coherence properties of isolated atoms with the sub-wavelength manipulation and strong light-matter interaction associated with nano-plasmonic systems. It allows one to considerably increase the energy scales in the realization of Hubbard models and to engineer effective long-range interactions in coherent and dissipative many-body dynamics. Realistic imperfections and potential applications are discussed.

  20. ELECTRONIC SPUTTERING: FROM ATOMIC PHYSICS

    E-Print Network [OSTI]

    Johnson, Robert E.

    ELECTRONIC SPUTTERING: FROM ATOMIC PHYSICS TO CONTINUUM MECHANICS Ejection of simple and complex molecules from surfaces probes the response of condensed matter to electronic excitations and has and Engineering Physics at the University of Virginia, Charlottesville. Bo Sundqvist holds the Chair in Ion

  1. Photoabsorption by Ions and Atoms

    SciTech Connect (OSTI)

    Manson, Steven T. [Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States)

    2004-12-01T23:59:59.000Z

    Recent progress in theoretical and experimental investigations of photoabsorption by atoms and ions is presented. Specifically, examples of near-chaotic behavior in photoionization of positive ions, low-energy manifestations of nondipole effects, high-energy breakdown of the single particle picture and new phenomenology uncovered in the inner-shell photoabsorption by negative ions are discussed.

  2. Remote atom entanglement in a fiber-connected three-atom system

    E-Print Network [OSTI]

    Guo Yan-Qing; Chen Jing; Song He-Shan

    2008-05-28T23:59:59.000Z

    An Ising-type atom-atom interaction is obtained in a fiber-connected three-atom system. The interaction is effective when $\\Delta\\approx \\gamma _{0}\\gg g$. The preparations of remote two-atom and three-atom entanglement governed by this interaction are discussed in specific parameters region. The overall two-atom entanglement is very small because of the existence of the third atom. However, the three-atom entanglement can reach a maximum very close to 1.

  3. Fiber optic integration in planar ion traps

    E-Print Network [OSTI]

    George, Elizabeth Marie

    2008-01-01T23:59:59.000Z

    Atomic ion traps are are excellent tools in atomic physics for studying single ions. Accurate measurement of the ion's electronic state in these ion traps is required by both atomic clocks and quantum computation. Quantum ...

  4. Radio-frequency dressed state potentials for neutral atoms

    E-Print Network [OSTI]

    S. Hofferberth; I. Lesanovsky; B. Fischer; J. Verdu; J. Schmiedmayer

    2006-08-29T23:59:59.000Z

    Potentials for atoms can be created by external fields acting on properties like magnetic moment, charge, polarizability, or by oscillating fields which couple internal states. The most prominent realization of the latter is the optical dipole potential formed by coupling ground and electronically excited states of an atom with light. Here we present an experimental investigation of the remarkable properties of potentials derived from radio-frequency (RF) coupling between electronic ground states. The coupling is magnetic and the vector character allows to design state dependent potential landscapes. On atom chips this enables robust coherent atom manipulation on much smaller spatial scales than possible with static fields alone. We find no additional heating or collisional loss up to densities approaching $10^{15}$ atoms / cm$^3$ compared to static magnetic traps. We demonstrate the creation of Bose-Einstein condensates in RF potentials and investigate the difference in the interference between two independently created and two coherently split condensates in identical traps. All together this makes RF dressing a powerful new tool for micro manipulation of atomic and molecular systems.

  5. Role of atomic collisions in fusion

    SciTech Connect (OSTI)

    Post, D.E.

    1982-04-01T23:59:59.000Z

    Atomic physics issues have played a large role in controlled fusion research. A general discussion of the present role of atomic processes in both magnetic and inertial controlled fusion work is presented.

  6. Preliminary steps to the Atomic Energy Commission

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

    program to the newly created Atomic Energy Commission. He had succeeded in ending the war, but the transition to peacetime use of atomic energy was not something the Army was...

  7. atomic kitteni lauljatar: Topics by E-print Network

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

    with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory...

  8. atoms barrasiye barhamkoneshhaye: Topics by E-print Network

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

    with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory...

  9. atomic mass spectrometry: Topics by E-print Network

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

    Negative *) Atomic composition Graham, Nick 3 Prospects in Analytical Atomic Spectrometry CERN Preprints Summary: Tendencies in five main branches of atomic spectrometry...

  10. Institute for Atom-Efficient Chemical Transformations Energy...

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

    adsorbed in a zirconium oxide nanobowl. The brown atoms are surface oxygen and the coral atoms are zirconium. Carbon, oxygen, and hydrogen atoms of fructose molecules are...

  11. Towards a high-precision atomic gyroscope

    E-Print Network [OSTI]

    Van Camp, Mackenzie A. (Mackenzie Anne)

    2013-01-01T23:59:59.000Z

    In this thesis, I report on the design and construction of the Rubidium Atomic Gyroscope Experiment (RAGE) at Draper Lab.

  12. Atomic Ordering Enhanced Electrocatalytic Activity of Nanoalloys...

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

    Ordering Enhanced Electrocatalytic Activity of Nanoalloys for Oxygen Reduction Reaction. Atomic Ordering Enhanced Electrocatalytic Activity of Nanoalloys for Oxygen Reduction...

  13. Atom interferometry with Bose-Einstein condensates in a double-well The applicability, accuracy, and sensitivity of atom interferometers may be improved

    E-Print Network [OSTI]

    Atom interferometry with Bose-Einstein condensates in a double-well potential The applicability properties of gaseous Bose-Einstein condensates in combination with the fine manipulation capabilities created a trapped-atom interferometer using gaseous Bose-Einstein condensates coherently split

  14. Chaotic Behaviour of Atomic Energy Levels

    E-Print Network [OSTI]

    A. Yilmaz; G. Hacibekiroglu; E. Bolcal; Y. Polatoglu

    2008-04-01T23:59:59.000Z

    The authors of this paper studied Schrodinger wave equation to investiagate the chaotic behavior of atomic energy levels in relation with three quantum numbers n, l, m by means of derived inequality. It could give rise to the siplitting of atomic spectral lines. Keywords: Chaos, Schrodinger wave equation, atomic energy levels

  15. Riso Report No. Danish Atomic Energy Commission

    E-Print Network [OSTI]

    Jagiellonski Institute of Physics Krakow, Poland and P. A. Lindgård Mogensen The Danish Atomic EnergyfM O o 8- OL '·O c/i Riso Report No. Danish Atomic Energy Commission Research Establishment Riso/t on exchangefrom: Library, Danish Atomic Energy Commission, Risd, Roskilde, Denmark #12;May, 1966 Ris6 Report No

  16. The Future of Atomic Energy

    DOE R&D Accomplishments [OSTI]

    Fermi, E.

    1946-05-27T23:59:59.000Z

    There is definitely a technical possibility that atomic power may gradually develop into one of the principal sources of useful power. If this expectation will prove correct, great advantages can be expected to come from the fact that the weight of the fuel is almost negligible. This feature may be particularly valuable for making power available to regions of difficult access and far from deposits of coal. It also may prove a great asset in mobile power units for example in a power plant for ship propulsion. On the negative side there are some technical limitations to be applicability of atomic power of which perhaps the most serious is the impossibility of constructing light power units; also there will be some peculiar difficulties in operating atomic plants, as for example the necessity of handling highly radioactive substances which will necessitate, at least for some considerable period, the use of specially skilled personnel for the operation. But the chief obstacle in the way of developing atomic power will be the difficulty of organizing a large scale industrial development in an internationally safe way. This presents actually problems much more difficult to solve than any of the technical developments that are necessary, It will require an unusual amount of statesmanship to balance properly the necessity of allaying the international suspicion that arises from withholding technical secrets against the obvious danger of dumping the details of the procedures for an extremely dangerous new method of warfare on a world that may not yet be prepared to renounce war. Furthermore, the proper balance should be found in the relatively short time that will elapse before the 'secrets' will naturally become open knowledge by rediscovery on part of the scientists and engineers of other countries.

  17. Entangling Atomic Spins with a Strong Rydberg-Dressed Interaction

    E-Print Network [OSTI]

    Jau, Y -Y; Keating, Tyler; Deutsch, I H; Biedermann, G W

    2015-01-01T23:59:59.000Z

    Controlling quantum entanglement between parts of a many-body system is the key to unlocking the power of quantum information processing for applications such as quantum computation, highprecision sensing, and simulation of many-body physics. Spin degrees of freedom of ultracold neutral atoms in their ground electronic state provide a natural platform given their long coherence times and our ability to control them with magneto-optical fields, but creating strong coherent coupling between spins has been challenging. We demonstrate a Rydberg-dressed ground-state blockade that provides a strong tunable interaction energy (~1 MHz in units of Planck's constant) between spins of individually trapped cesium atoms. With this interaction we directly produce Bell-state entanglement between two atoms with a fidelity >= 81(2)%, excluding atom loss events, and >= 60(3)% when loss is included.

  18. Optimal trajectories for efficient atomic transport without final excitation

    E-Print Network [OSTI]

    Xi Chen; E. Torrontegui; Dionisis Stefanatos; Jr-Shin Li; J. G. Muga

    2011-08-08T23:59:59.000Z

    We design optimal harmonic-trap trajectories to transport cold atoms without final excitation, combining an inverse engineering techniqe based on Lewis-Riesenfeld invariants with optimal control theory. Since actual traps are not really harmonic, we keep the relative displacement between the center of mass and the trap center bounded. Under this constraint, optimal protocols are found according to different physical criteria. The minimum time solution has a "bang-bang" form, and the minimum displacement solution is of "bang-off-bang" form. The optimal trajectories for minimizing the transient energy are also discussed.

  19. Gauge invariant hydrogen atom Hamiltonian

    E-Print Network [OSTI]

    Wei-Min Sun; Xiang-Song Chen; Xiao-Fu Lu; Fan Wang

    2010-06-22T23:59:59.000Z

    For quantum mechanics of a charged particle in a classical external electromagnetic field, there is an apparent puzzle that the matrix element of the canonical momentum and Hamiltonian operators is gauge dependent. A resolution to this puzzle is recently provided by us in [2]. Based on the separation of the electromagnetic potential into pure gauge and gauge invariant parts, we have proposed a new set of momentum and Hamiltonian operators which satisfy both the requirement of gauge invariance and the relevant commutation relations. In this paper we report a check for the case of the hydrogen atom problem: Starting from the Hamiltonian of the coupled electron, proton and electromagnetic field, under the infinite proton mass approximation, we derive the gauge invariant hydrogen atom Hamiltonian and verify explicitly that this Hamiltonian is different from the Dirac Hamiltonian, which is the time translation generator of the system. The gauge invariant Hamiltonian is the energy operator, whose eigenvalue is the energy of the hydrogen atom. It is generally time-dependent. In this case, one can solve the energy eigenvalue equation at any specific instant of time. It is shown that the energy eigenvalues are gauge independent, and by suitably choosing the phase factor of the time-dependent eigenfunction, one can ensure that the time-dependent eigenfunction satisfies the Dirac equation.

  20. NAAP Hydrogen Atom 1/9 The Hydrogen Atom Student Guide

    E-Print Network [OSTI]

    Farritor, Shane

    Name: NAAP ­ Hydrogen Atom 1/9 The Hydrogen Atom ­ Student Guide Background Material Carefully read and the Quantum model represent the Hydrogen atom. In some cases they both describe things in the same way frequency, smaller energy, and the same velocity through space as a blue photon". #12;NAAP ­Hydrogen Atom 2

  1. Fast transport, atom sample splitting and single-atom qubit supply in two-dimensional arrays

    E-Print Network [OSTI]

    Birkl, Gerhard

    Fast transport, atom sample splitting and single-atom qubit supply in two-dimensional arrays architecture for neutral atom quantum information processing, quantum simulation and the manipulation of ultra-cold implemented functions. We introduce piezo-actuator-based transport of atom ensembles over distances of more

  2. Ultracold-atom collisions in atomic waveguides : A two-channel analysis

    E-Print Network [OSTI]

    Tom Kristensen; Ludovic Pricoupenko

    2015-04-16T23:59:59.000Z

    Low dimensional behavior of two ultra-cold atoms trapped in two-and one-dimensional waveguides is investigated in the vicinity of a magnetic Feshbach resonance. A quantitative two-channel model for the Feshbach mechanism is used allowing an exhaustive analysis of low-dimensional resonant scattering behavior and of the confinement induced bound states. The role of the different parameters of the resonance is depicted in this context. Results are compared with the ones of the zero-range approach. The relevance of the effective range approximation in low dimensions is studied. Examples of known resonances are used to illustrate the bound state properties.

  3. Ultracold Atoms: How Quantum Field Theory Invaded Atomic 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin TransitionProgram |Frank CasellaEnergyUltracold Atoms: How Quantum

  4. Engineering Atomic Quantum Reservoirs for Photons

    E-Print Network [OSTI]

    Susanne Pielawa; Luiz Davidovich; David Vitali; Giovanna Morigi

    2010-04-06T23:59:59.000Z

    We present protocols for creating entangled states of two modes of the electromagnetic field, by using a beam of atoms crossing microwave resonators. The atoms are driven by a transverse, classical field and pump correlated photons into (i) two modes of a cavity and (ii) the modes of two distant cavities. The protocols are based on a stochastic dynamics, characterized by random arrival times of the atoms and by random interaction times between atoms and cavity modes. The resulting effective model yields a master equation, whose steady state is an entangled state of the cavity modes. In this respect, the atoms act like a quantum reservoir, pulling the cavity modes into an entangled, Einstein-Podolski-Rosen (EPR) state, whose degree of entanglement is controlled by the intensity and the frequency of the transverse field. This scheme is robust against stochastic fluctuations in the atomic beam, and it does not require atomic detection nor velocity selection.

  5. Engineering Atomic Quantum Reservoirs for Photons

    E-Print Network [OSTI]

    Pielawa, Susanne; Vitali, David; Morigi, Giovanna

    2010-01-01T23:59:59.000Z

    We present protocols for creating entangled states of two modes of the electromagnetic field, by using a beam of atoms crossing microwave resonators. The atoms are driven by a transverse, classical field and pump correlated photons into (i) two modes of a cavity and (ii) the modes of two distant cavities. The protocols are based on a stochastic dynamics, characterized by random arrival times of the atoms and by random interaction times between atoms and cavity modes. The resulting effective model yields a master equation, whose steady state is an entangled state of the cavity modes. In this respect, the atoms act like a quantum reservoir, pulling the cavity modes into an entangled, Einstein-Podolski-Rosen (EPR) state, whose degree of entanglement is controlled by the intensity and the frequency of the transverse field. This scheme is robust against stochastic fluctuations in the atomic beam, and it does not require atomic detection nor velocity selection.

  6. atomic recoil laser: Topics by E-print Network

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

    Atomic Recoil Laser Quantum Physics (arXiv) Summary: We formulate a wave atom optics theory of the Collective Atomic Recoil Laser, where the atomic center-of-mass motion...

  7. arXiv:1101.0686v1[physics.atom-ph]4Jan2011 Characteristics of integrated magneto-optical traps

    E-Print Network [OSTI]

    on an isolated pyramid, with hand-wound coils generating the trapping magnetic field. This was later replaced, and because they are micro-fabricated it is easy to form several pyramid MOTs on the same chip. In this paper hydroxide to form concave pyramidal hollows. The sides of the pyramids range in length L from 4.2 mm down

  8. Atomic Structure Calculations from the Los Alamos Atomic Physics Codes

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Cowan, R. D.

    The well known Hartree-Fock method of R.D. Cowan, developed at Los Alamos National Laboratory, is used for the atomic structure calculations. Electron impact excitation cross sections are calculated using either the distorted wave approximation (DWA) or the first order many body theory (FOMBT). Electron impact ionization cross sections can be calculated using the scaled hydrogenic method developed by Sampson and co-workers, the binary encounter method or the distorted wave method. Photoionization cross sections and, where appropriate, autoionizations are also calculated. Original manuals for the atomic structure code, the collisional excitation code, and the ionization code, are available from this website. Using the specialized interface, you will be able to define the ionization stage of an element and pick the initial and final configurations. You will be led through a series of web pages ending with a display of results in the form of cross sections, collision strengths or rates coefficients. Results are available in tabular and graphic form.

  9. Moøller polarimetry with polarized atomic hydrogen at MESA

    SciTech Connect (OSTI)

    Bartolomé, P. Aguar; Aulenbacher, K.; Tyukin, V. [Institut für Kernphysik, Johannes Gutenberg-University, D-55099 Mainz (Germany)

    2013-11-07T23:59:59.000Z

    A new generation of parity violation (PV) electron scattering experiments are planned to be carried out at the Institut für Kernphysik in Mainz. These experiments will be performed at low energies of 100-200 MeV using the new accelerator MESA (Mainz Energy recovering Superconducting Accelerator). One of the main challenges of such experiments is to achieve an accuracy in beam polarization measurements that must be below 0.5%. This very high accuracy can be reached using polarized atomic hydrogen gas, stored in an ultra-cold magnetic trap, as the target for electron beam polarimetry based on Mo/ller scattering. Electron spin-polarized atomic hydrogen can be stored at high densities of 10{sup 16} cm{sup ?2}, over relatively long time periods, in a high magnetic field (8T) and at low temperatures (0.3K). The gradient force splits the ground state of the hydrogen into four states with different energies. Atoms in the low energy states are trapped in the strong magnetic field region whereas the high energy states are repelled and pumped away. The physics of ultra-cold atomic hydrogen in magnetic traps and the status of the Mainz Hydro-Mo/ller project will be presented.

  10. Sub-Poissonian atom number fluctuations using light-assisted collisions

    E-Print Network [OSTI]

    Y. R. P. Sortais; A. Fuhrmanek; R. Bourgain; A. Browaeys

    2012-01-23T23:59:59.000Z

    We investigate experimentally the number statistics of a mesoscopic ensemble of cold atoms in a microscopic dipole trap loaded from a magneto-optical trap, and find that the atom number fluctuations are reduced with respect to a Poisson distribution due to light-assisted two-body collisions. For numbers of atoms N>2, we measure a reduction factor (Fano factor) of 0.72+/-0.07, which differs from 1 by more than 4 standard deviations. We analyze this fact by a general stochastic model describing the competition between the loading of the trap from a reservoir of cold atoms and multi-atom losses, which leads to a master equation. Applied to our experimental regime, this model indicates an asymptotic value of 3/4 for the Fano factor at large N and in steady state. We thus show that we have reached the ultimate level of reduction in number fluctuations in our system.

  11. General Atomics | Open Energy Information

    Open Energy Info (EERE)

    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 Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdf Jump1946865°,Park, Texas:Webinars/Puesta en Marcha,Geary,GenSelfandAtomics

  12. ccsd-00001508,version1-1May2004 Realization of a magnetically guided atomic beam in the collisional regime

    E-Print Network [OSTI]

    Boyer, Edmond

    to periodically re- plenish with new condensates a gas sample held in an optical dipole trap. The second-Einstein condensation (BEC) [2] and pulsed "atom lasers" extracted from the condensate [3]. These advances in atom atom laser"). The first possibility [4] consists in using the "standard" condensation procedure

  13. Atoms can be divided into three categories: polar, non-polar and hydrogen atom

    E-Print Network [OSTI]

    Pei-Lin You

    2010-10-10T23:59:59.000Z

    Since the time of Rutherford 1911) physicists and chemists commonly believed that with no electric field, the nucleus of an atom is at the centre of the electron cloud, atoms do not have permanent electric dipole moment (EDM), so that there is no polar atom in nature. In the fact, the idea is untested hypothesis. After ten years of intense research, our experiments showed that atoms can be divided into three categories: polar, non-polar and hydrogen atom. Alkali atoms are all polar atoms. The EDM of a Sodium, Potassium, Rubidium and Cesium atom in the ground state have been obtained as follows: d(Na)=1.28*10 to-8 power e.cm; d(K)=1.58*10 to-8 power e.cm; d(Rb)=1.70 *10 to-8 power e.cm; d(Cs)=1.86*10 to-8 power e.cm. All kind of atoms are non-polar atoms except for alkali and hydrogen atoms. Hydrogen atom is quite distinct from the others. The ground state in hydrogen is non-polar atom(d=0) but the excited state is polar atom, for example, the first excited state has a large EDM: d(H)=3ea=1.59*10 to-8 power e.cm (a is Bohr radius).

  14. Coherence and Raman Sideband Cooling of a Single Atom in an Optical Tweezer

    E-Print Network [OSTI]

    Thompson, J. D.

    We investigate quantum control of a single atom in a tightly focused optical tweezer trap. We show that inevitable spatially varying polarization gives rise to significant internal-state decoherence but that this effect ...

  15. Multichannel calculations for frequency shift and line broadening cross sections in collisions of cold hydrogen atoms

    E-Print Network [OSTI]

    Zygelman, B.; Jamieson, M.J.

    Zygelman,B. Jamieson,M.J. Stancil,P.C. Dalgarno,A. Workshop on Collisions of Cold Trapped Atoms at Joint Institute for Laboratory Astrophysics, Boulder, CO, U.S.A.

  16. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V. C.; Wang, Chengpu

    2006-08-22T23:59:59.000Z

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  17. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V.; Wang, Chengpu

    2004-11-16T23:59:59.000Z

    An atomic force microscope is described having a cantilever comprising a base and a probe tip on an end opposite the base; a cantilever drive device connected to the base; a magnetic material coupled to the probe tip, such that when an incrementally increasing magnetic field is applied to the magnetic material an incrementally increasing force will be applied to the probe tip; a moveable specimen base; and a controller constructed to obtain a profile height of a specimen at a point based upon a contact between the probe tip and a specimen, and measure an adhesion force between the probe tip and the specimen by, under control of a program, incrementally increasing an amount of a magnetic field until a release force, sufficient to break the contact, is applied. An imaging method for atomic force microscopy involving measuring a specimen profile height and adhesion force at multiple points within an area and concurrently displaying the profile and adhesion force for each of the points is also described. A microscope controller is also described and is constructed to, for a group of points, calculate a specimen height at a point based upon a cantilever deflection, a cantilever base position and a specimen piezo position; calculate an adhesion force between a probe tip and a specimen at the point by causing an incrementally increasing force to be applied to the probe tip until the probe tip separates from a specimen; and move the probe tip to a new point in the group.

  18. Sensing mode atomic force microscope

    DOE Patents [OSTI]

    Hough, Paul V. C. (Port Jefferson, NY); Wang, Chengpu (Upton, NY)

    2003-01-01T23:59:59.000Z

    An atomic force microscope utilizes a pulse release system and improved method of operation to minimize contact forces between a probe tip affixed to a flexible cantilever and a specimen being measured. The pulse release system includes a magnetic particle affixed proximate the probe tip and an electromagnetic coil. When energized, the electromagnetic coil generates a magnetic field which applies a driving force on the magnetic particle sufficient to overcome adhesive forces exhibited between the probe tip and specimen. The atomic force microscope includes two independently displaceable piezo elements operable along a Z-axis. A controller drives the first Z-axis piezo element to provide a controlled approach between the probe tip and specimen up to a point of contact between the probe tip and specimen. The controller then drives the first Z-axis piezo element to withdraw the cantilever from the specimen. The controller also activates the pulse release system which drives the probe tip away from the specimen during withdrawal. Following withdrawal, the controller adjusts the height of the second Z-axis piezo element to maintain a substantially constant approach distance between successive samples.

  19. Hydrogen Atom in Relativistic Motion

    E-Print Network [OSTI]

    M. Jarvinen

    2005-04-11T23:59:59.000Z

    The Lorentz contraction of bound states in field theory is often appealed to in qualitative descriptions of high energy particle collisions. Surprisingly, the contraction has not been demonstrated explicitly even in simple cases such as the hydrogen atom. It requires a calculation of wave functions evaluated at equal (ordinary) time for bound states in motion. Such wave functions are not obtained by kinematic boosts from the rest frame. Starting from the exact Bethe-Salpeter equation we derive the equal-time wave function of a fermion-antifermion bound state in QED, i.e., positronium or the hydrogen atom, in any frame to leading order in alpha. We show explicitly that the bound state energy transforms as the fourth component of a vector and that the wave function of the fermion-antifermion Fock state contracts as expected. Transverse photon exchange contributes at leading order to the binding energy of the bound state in motion. We study the general features of the corresponding fermion-antifermion-photon Fock states, and show that they do not transform by simply contracting. We verify that the wave function reduces to the light-front one in the infinite momentum frame.

  20. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Jan Rudolph; Waldemar Herr; Christoph Grzeschik; Tammo Sternke; Alexander Grote; Manuel Popp; Dennis Becker; Hauke Müntinga; Holger Ahlers; Achim Peters; Claus Lämmerzahl; Klaus Sengstock; Naceur Gaaloul; Wolfgang Ertmer; Ernst M. Rasel

    2015-06-16T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a challenging endeavor. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6$\\,$s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1$\\,$Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based BEC experiments while offering significantly higher repetition rates. Additionally, the flux is approaching those of current interferometers employing Raman-type velocity selection of laser-cooled atoms. The compact and robust design allows for mobile operation in a variety of demanding environments and paves the way for transportable high-precision quantum sensors.

  1. Preparation of three-dimensional entanglement for distant atoms in coupled cavities via atomic spontaneous emission and cavity decay

    E-Print Network [OSTI]

    Shi-Lei Su; Xiao-Qiang Shao; Hong-Fu Wang; Shou Zhang

    2014-08-21T23:59:59.000Z

    We propose a dissipative scheme to prepare a three-dimensional entangled state for two atoms trapped in separate coupled cavities. Our work shows that both atomic spontaneous emission and cavity decay, which are two typical obstacles in unitary-dynamics-based schemes, could be utilized as resources for high-dimensional entangled state preparation without specifying initial state and controlling time precisely. Final numerical simulation with one group of experimental parameters indicates that the performance of our scheme is better than the unitary-dynamics-based scheme.

  2. Phases of Atom-Molecule Vortex Matter

    SciTech Connect (OSTI)

    Woo, S. J.; Bigelow, N. P. [Department of Physics and Astronomy, University of Rochester, Rochester, New York (United States); Park, Q-Han [Department of Physics, Korea University, Seoul (Korea, Republic of)

    2008-03-28T23:59:59.000Z

    We study ground state vortex configurations in a rotating atom-molecule Bose-Einstein condensate. It is found that the coherent coupling between the atomic and molecular condensates can render a pairing of atomic and molecular vortices into a composite structure that resembles a carbon dioxide molecule. Structural phase transitions of vortex lattices are also explored through different physical parameters including the rotational frequency of the system.

  3. Method for enhanced atomization of liquids

    DOE Patents [OSTI]

    Thompson, Richard E. (27121 Puerta del Oro, Mission Viejo, CA 92691); White, Jerome R. (44755 Wyandotte, Hemet, CA 92544)

    1993-01-01T23:59:59.000Z

    In a process for atomizing a slurry or liquid process stream in which a slurry or liquid is passed through a nozzle to provide a primary atomized process stream, an improvement which comprises subjecting the liquid or slurry process stream to microwave energy as the liquid or slurry process stream exits the nozzle, wherein sufficient microwave heating is provided to flash vaporize the primary atomized process stream.

  4. CERTIFICATION DOCKET WESTINGHOUSE ATOMIC POWER DEVELOPMENT PLANT

    Office of Legacy Management (LM)

    Westinghouse Atomic 1 U.S. Department of Energy Interim Residual Contamination and Waste Control Guidelines for bormerly Utilized Sites Remedial Action Program (FUSRAP) d Remote...

  5. Atomic 'mismatch' creates nano 'dumbbells' | Argonne National...

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

    Atomic 'mismatch' creates nano 'dumbbells' By Jared Sagoff * December 4, 2014 Tweet EmailPrint ARGONNE, Ill. - Like snowflakes, nanoparticles come in a wide variety of shapes and...

  6. Atomic Energy and Nuclear Materials Program (Tennessee)

    Broader source: Energy.gov [DOE]

    The Atomic Energy and Nuclear Materials section of the Tennessee Code covers all of the regulations, licenses, permits, siting requirements, and practices relevant to a nuclear energy development. ...

  7. Classical and Quantum Chaos in Atom Optics

    E-Print Network [OSTI]

    Farhan Saif

    2006-04-10T23:59:59.000Z

    The interaction of an atom with an electromagnetic field is discussed in the presence of a time periodic external modulating force. It is explained that a control on atom by electromagnetic fields helps to design the quantum analog of classical optical systems. In these atom optical systems chaos may appear at the onset of external fields. The classical and quantum chaotic dynamics is discussed, in particular in an atom optics Fermi accelerator. It is found that the quantum dynamics exhibits dynamical localization and quantum recurrences.

  8. United States Atomic Energy Commission formed

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

    weapons problem, the United States worked to establish its own formal organization. The transition from military civilian control of nuclear energy was defined in the Atomic...

  9. Distribution Category: Atomic, Molecular, and Chemical Physics

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

    Atomic, Molecular, and Chemical Physics (UC-411) ARGONNE NATIONAL LABORATORY 9700 South Cass Avenue Argonne, TIlinois 60439 ANLI APSILS-151 RESULTS OF DESIGN CALCULATIONS FOR THE...

  10. Gas Atomization of Stainless Steel - Slow Motion

    SciTech Connect (OSTI)

    None

    2011-01-01T23:59:59.000Z

    Stainless steel liquid atomized by supersonic argon gas into a spray of droplets at ~1800ºC. Atomization of metal requires high pressure gas and specialized chambers for cooling and collecting the powders without contamination. The critical step for morphological control is the impingement of the gas on the melt stream. The video is a black and white high speed video of a liquid metal stream being atomized by high pressure gas. This material was atomized at the Ames Laboratory's Materials Preparation Center http://www.mpc.ameslab.gov

  11. Subwavelength Transportation of Light with Atomic Resonances

    E-Print Network [OSTI]

    Chui, Siu-Tat; Jo, Gyu-Boong

    2015-01-01T23:59:59.000Z

    We propose and investigate a new type of optical waveguide made by an array of atoms without involving conventional Bragg scattering or total internal reflection. A finite chain of atoms collectively coupled through their intrinsic resonance supports a propagating mode with minimal radiative loss when the array spacing $a$ is around 0.6$\\lambda_0/2\\pi$ where $\\lambda_0$ is the wavelength of the nearly resonant optical transition. We find that the transportation is robust with respect to position fluctuation and remains possible when the atoms are placed on a circle. Our result paves the way to implement the subwavelength transportation of light in integrated optical circuits with cold atoms.

  12. Sensitivity of ultracold atoms to quantized flux in a superconducting ring

    E-Print Network [OSTI]

    Weiss, P; Bernon, S; Bothner, D; Sárkány, L; Zimmermann, C; Kleiner, R; Koelle, D; Fortágh, J; Hattermann, H

    2015-01-01T23:59:59.000Z

    We report on the magnetic trapping of an ultracold ensemble of $^{87}$Rb atoms close to a superconducting ring prepared in different states of quantized magnetic flux. The niobium ring of 10 $\\mu$m radius is prepared in a flux state $n \\Phi_0$, with $\\Phi_0 = h / 2e$ the flux quantum and $n$ varies between $\\pm 5$. An atomic cloud of 250 nK temperature is positioned with a harmonic magnetic trapping potential at $\\sim 18 \\mu$m distance below the ring. The inhomogeneous magnetic field of the supercurrent in the ring contributes to the magnetic trapping potential of the cloud. The induced deformation of the magnetic trap impacts the shape of the cloud, the number of trapped atoms as well as the center-of-mass oscillation frequency of Bose-Einstein condensates. When the field applied during cooldown of the chip is varied, the change of these properties shows discrete steps that quantitatively match flux quantization.

  13. CARBON ATOM DISTRIBUTION IN A DUAL PHASE STEEL: AN ATOM PROBE STUDY

    E-Print Network [OSTI]

    Barnard, S.J.

    2014-01-01T23:59:59.000Z

    ATOM DISTRIBUTION IN A DUAL PHASE STEEL: AN ATOM PROBE STUDY~4720 1 U.S.A. IntroductioE. Dual Phase steels are currentlymartensite-austenite dual phase steel, although the results

  14. Vibrational Modes of Adsorbed Atoms

    E-Print Network [OSTI]

    LAWRENCE, WR; Allen, Roland E.

    1977-01-01T23:59:59.000Z

    of adsorbed atoms. vi rational modes *Present address: S h University of H c ool of Scienc City, Tex. ouston at Clear La ', r e e and Technology Lake City, Clea Lak %. R. wrence and R. E. Allen published). Allen, Phys. Rev. B (to be 2G. P... are about t r Ne on Kr. The d ou he same as fo mode labeled 2V a as large in the f' t X is almost erst (adsorbate) la e od( b t t)l pure surface mod e ayer. The 1H mode at X is a 4, this mode bec m e. Just to the r'right of X in Fig. e ecomes a...

  15. Topological Insulators and Metals in Atomic Optical Lattices

    E-Print Network [OSTI]

    Tudor D. Stanescu; Victor Galitski; J. Y. Vaishnav; Charles W. Clark; S. Das Sarma

    2009-01-26T23:59:59.000Z

    We propose the realization of topological quantum states with cold atoms trapped in an optical lattice. We discuss an experimental setup that generates a two-dimensional hexagonal lattice in the presence of a light-induced periodic vector potential, which represents a realization of the Haldane model with cold atoms. We determine theoretically the conditions necessary for observing the topological states and show that two of the key conditions are: 1) the realization of sharp boundaries and 2) the minimization of any smoothly varying component of the confining potential. We argue that, unlike their condensed matter counterparts, cold atom topological quantum states can be i) "seen", by mapping out the characteristic chiral edge states, and ii) controlled, by controlling the periodic vector potential and the properties of the confining potential.

  16. Design of a dual species atom interferometer for space

    E-Print Network [OSTI]

    Thilo Schuldt; Christian Schubert; Markus Krutzik; Lluis Gesa Bote; Naceur Gaaloul; Jonas Hartwig; Holger Ahlers; Waldemar Herr; Katerine Posso-Trujillo; Jan Rudolph; Stephan Seidel; Thijs Wendrich; Wolfgang Ertmer; Sven Herrmann; André Kubelka-Lange; Alexander Milke; Benny Rievers; Emanuele Rocco; Andrew Hinton; Kai Bongs; Markus Oswald; Matthias Franz; Matthias Hauth; Achim Peters; Ahmad Bawamia; Andreas Wicht; Baptiste Battelier; Andrea Bertoldi; Philippe Bouyer; Arnaud Landragin; Didier Massonnet; Thomas Lévèque; Andre Wenzlawski; Ortwin Hellmig; Patrick Windpassinger; Klaus Sengstock; Wolf von Klitzing; Chris Chaloner; David Summers; Philip Ireland; Ignacio Mateos; Carlos F. Sopuerta; Fiodor Sorrentino; Guglielmo M. Tino; Michael Williams; Christian Trenkel; Domenico Gerardi; Michael Chwalla; Johannes Burkhardt; Ulrich Johann; Astrid Heske; Eric Wille; Martin Gehler; Luigi Cacciapuoti; Norman Gürlebeck; Claus Braxmaier; Ernst Rasel

    2014-12-08T23:59:59.000Z

    Atom interferometers have a multitude of proposed applications in space including precise measurements of the Earth's gravitational field, in navigation & ranging, and in fundamental physics such as tests of the weak equivalence principle (WEP) and gravitational wave detection. While atom interferometers are realized routinely in ground-based laboratories, current efforts aim at the development of a space compatible design optimized with respect to dimensions, weight, power consumption, mechanical robustness and radiation hardness. In this paper, we present a design of a high-sensitivity differential dual species $^{85}$Rb/$^{87}$Rb atom interferometer for space, including physics package, laser system, electronics and software. The physics package comprises the atom source consisting of dispensers and a 2D magneto-optical trap (MOT), the science chamber with a 3D-MOT, a magnetic trap based on an atom chip and an optical dipole trap (ODT) used for Bose-Einstein condensate (BEC) creation and interferometry, the detection unit, the vacuum system for $10^{-11}$ mbar ultra-high vacuum generation, and the high-suppression factor magnetic shielding as well as the thermal control system. The laser system is based on a hybrid approach using fiber-based telecom components and high-power laser diode technology and includes all laser sources for 2D-MOT, 3D-MOT, ODT, interferometry and detection. Manipulation and switching of the laser beams is carried out on an optical bench using Zerodur bonding technology. The instrument consists of 9 units with an overall mass of 221 kg, an average power consumption of 608 W (819 W peak), and a volume of 470 liters which would well fit on a satellite to be launched with a Soyuz rocket, as system studies have shown.

  17. Stable heteronuclear few-atom bound states in mixed dimensions

    SciTech Connect (OSTI)

    Yin Tao; Zhang Peng; Zhang Wei [Department of Physics, Renmin University of China, Beijing 100872 (China)

    2011-11-15T23:59:59.000Z

    We study few-body problems in mixed dimensions where two or three heavy atoms are trapped individually in parallel one-dimensional tubes or two-dimensional disks and a single light atom travels freely in three dimensions. Using the Born-Oppenheimer approximation, we find three- and four-body bound states for a broad parameter region. Specifically, the existence of trimer and tetramer states persists to the negative scattering length regime, where no two-body bound state is present. As pointed out by Y. Nishida in an earlier work [Phys. Rev. A 82, 011605(R) (2010)], these few-body bound states are stable against three-body recombination due to geometric separation. In addition, we find that the binding energy of the ground trimer and tetramer state reaches its maximum value when the scattering lengths are comparable to the separation between the low-dimensional traps.

  18. Probing the Kondo Lattice Model with Alkaline Earth Atoms

    E-Print Network [OSTI]

    Michael Foss-Feig; Michael Hermele; Ana Maria Rey

    2009-12-24T23:59:59.000Z

    We study transport properties of alkaline-earth atoms governed by the Kondo Lattice Hamiltonian plus a harmonic confining potential, and suggest simple dynamical probes of several different regimes of the phase diagram that can be implemented with current experimental techniques. In particular, we show how Kondo physics at strong coupling, low density, and in the heavy fermion phase is manifest in the dipole oscillations of the conduction band upon displacement of the trap center.

  19. Edge Transport in 2D Cold Atom Optical Lattices

    E-Print Network [OSTI]

    V. W. Scarola; S. Das Sarma

    2007-05-24T23:59:59.000Z

    We theoretically study the observable response of edge currents in two dimensional cold atom optical lattices. As an example we use Gutzwiller mean-field theory to relate persistent edge currents surrounding a Mott insulator in a slowly rotating trapped Bose-Hubbard system to time of flight measurements. We briefly discuss an application, the detection of Chern number using edge currents of a topologically ordered optical lattice insulator.

  20. Relativistic atomic physics at the SSC

    SciTech Connect (OSTI)

    NONE

    1990-12-31T23:59:59.000Z

    This report discusses the following proposed work for relativistic atomic physics at the Superconducting Super Collider: Beam diagnostics; atomic physics research; staffing; education; budget information; statement concerning matching funds; description and justification of major items of equipment; statement of current and pending support; and assurance of compliance.

  1. Atomic processes in high-density plasmas

    SciTech Connect (OSTI)

    More, R.M.

    1982-12-21T23:59:59.000Z

    This review covers dense atomic plasmas such as that produced in inertial confinement fusion. The target implosion physics along with the associated atomic physics, i.e., free electron collision phenomena, electron states I, electron states II, and nonequilibrium plasma states are described. (MOW)

  2. Photoassociative molecular spectroscopy for atomic radiative lifetimes.

    E-Print Network [OSTI]

    Boyer, Edmond

    very far apart, in so-called long- range molecular states, their mutual interaction is ruled by plain atomic properties. The high- resolution spectroscopic study of some molecular excited states populated by photoassociation of cold atoms (photoassociative spectroscopy) gives a good illustration of this property

  3. Sagnac interferometry with a single atomic clock

    E-Print Network [OSTI]

    Stevenson, R; Bishop, T; Lesanovsky, I; Fernholz, T

    2015-01-01T23:59:59.000Z

    We theoretically discuss an implementation of a Sagnac interferometer with cold atoms. In contrast to currently existing schemes our protocol does not rely on any free propagation of atoms. Instead it is based on superpositions of fully confined atoms and state-dependent transport along a closed path. Using Ramsey sequences for an atomic clock, the accumulated Sagnac phase is encoded in the resulting population imbalance between two internal (clock) states. Using minimal models for the above protocol we analytically quantify limitations arising from atomic dynamics and finite temperature. We discuss an actual implementation of the interferometer with adiabatic radio-frequency potentials that is inherently robust against common mode noise as well as phase noise from the reference oscillator.

  4. Sagnac interferometry with a single atomic clock

    E-Print Network [OSTI]

    R. Stevenson; M. Hush; T. Bishop; I. Lesanovsky; T. Fernholz

    2015-04-21T23:59:59.000Z

    We theoretically discuss an implementation of a Sagnac interferometer with cold atoms. In contrast to currently existing schemes our protocol does not rely on any free propagation of atoms. Instead it is based on superpositions of fully confined atoms and state-dependent transport along a closed path. Using Ramsey sequences for an atomic clock, the accumulated Sagnac phase is encoded in the resulting population imbalance between two internal (clock) states. Using minimal models for the above protocol we analytically quantify limitations arising from atomic dynamics and finite temperature. We discuss an actual implementation of the interferometer with adiabatic radio-frequency potentials that is inherently robust against common mode noise as well as phase noise from the reference oscillator.

  5. On the energy of electric field in hydrogen atom

    E-Print Network [OSTI]

    Yuri Kornyushin

    2009-07-30T23:59:59.000Z

    It is shown that hydrogen atom is a unique object in physics having negative energy of electric field, which is present in the atom. This refers also to some hydrogen-type atoms: hydrogen anti-atom, atom composed of proton and antiproton, and positronium.

  6. Engineering atom-atom thermal entanglement via two-photon process

    E-Print Network [OSTI]

    Y. Q. Guo; L. Zhou; H. S. Song

    2005-09-21T23:59:59.000Z

    We study the system that two atoms simultaneously interact with a single-mode thermal field via different couplings and different spontaneous emission rates when two-photon process is involved. It is found that we indeed can employ the different couplings to produce the atom-atom thermal entanglement in two-photon process. The different atomic spontaneous emission rates are also utilizable in generating thermal entanglement. We also investigate the effect of the cavity leakage. To the initial atomic state $|ee> ,$a slight leakage can relieve the restriction of interaction time and we can obtain a large and steady entanglement.

  7. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Jan Rudolph; Waldemar Herr; Christoph Grzeschik; Tammo Sternke; Alexander Grote; Manuel Popp; Dennis Becker; Hauke Müntinga; Holger Ahlers; Achim Peters; Claus Lämmerzahl; Klaus Sengstock; Naceur Gaaloul; Wolfgang Ertmer; Ernst M. Rasel

    2015-01-02T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a technological challenge. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6 s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1 Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based experiments while offering significantly higher repetition rates. The compact and robust design allows for mobile operation in a variety of demanding environments and paves the way for portable high-precision quantum sensors.

  8. A high-flux BEC source for mobile atom interferometers

    E-Print Network [OSTI]

    Rudolph, Jan; Grzeschik, Christoph; Sternke, Tammo; Grote, Alexander; Popp, Manuel; Becker, Dennis; Müntinga, Hauke; Ahlers, Holger; Peters, Achim; Lämmerzahl, Claus; Sengstock, Klaus; Gaaloul, Naceur; Ertmer, Wolfgang; Rasel, Ernst M

    2015-01-01T23:59:59.000Z

    Quantum sensors based on coherent matter-waves are precise measurement devices whose ultimate accuracy is achieved with Bose-Einstein condensates (BEC) in extended free fall. This is ideally realized in microgravity environments such as drop towers, ballistic rockets and space platforms. However, the transition from lab-based BEC machines to robust and mobile sources with comparable performance is a technological challenge. Here we report on the realization of a miniaturized setup, generating a flux of $4 \\times 10^5$ quantum degenerate $^{87}$Rb atoms every 1.6 s. Ensembles of $1 \\times 10^5$ atoms can be produced at a 1 Hz rate. This is achieved by loading a cold atomic beam directly into a multi-layer atom chip that is designed for efficient transfer from laser-cooled to magnetically trapped clouds. The attained flux of degenerate atoms is on par with current lab-based experiments while offering significantly higher repetition rates. The compact and robust design allows for mobile operation in a variety of...

  9. Ultralong-Range Rydberg Molecules in a Divalent-Atomic System

    E-Print Network [OSTI]

    DeSalvo, B J; Dunning, F B; Killian, T C; Sadeghpour, H R; Yoshida, S; Burgdörfer, J

    2015-01-01T23:59:59.000Z

    We report the creation of ultralong-range Sr$_2$ molecules comprising one ground-state $5s^2$ $^1S_0$ atom and one atom in a $5sns$ $^3S_1$ Rydberg state for $n$ ranging from 29 to 36. Molecules are created in a trapped ultracold atomic gas using two-photon excitation near resonant with the $5s5p$ $^3P_1$ intermediate state, and their formation is detected through ground-state atom loss from the trap. The observed molecular binding energies are fit with the aid of first-order perturbation theory that utilizes a Fermi pseudopotential with effective $s$-wave and $p$-wave scattering lengths to describe the interaction between an excited Rydberg electron and a ground-state Sr atom.

  10. Quantum Control of Qubits and Atomic Motion Using Ultrafast Laser Pulses

    E-Print Network [OSTI]

    J. Mizrahi; B. Neyenhuis; K. Johnson; W. C. Campbell; C. Senko; D. Hayes; C. Monroe

    2013-07-01T23:59:59.000Z

    Pulsed lasers offer significant advantages over CW lasers in the coherent control of qubits. Here we review the theoretical and experimental aspects of controlling the internal and external states of individual trapped atoms with pulse trains. Two distinct regimes of laser intensity are identified. When the pulses are sufficiently weak that the Rabi frequency $\\Omega$ is much smaller than the trap frequency $\\otrap$, sideband transitions can be addressed and atom-atom entanglement can be accomplished in much the same way as with CW lasers. By contrast, if the pulses are very strong ($\\Omega \\gg \\otrap$), impulsive spin-dependent kicks can be combined to create entangling gates which are much faster than a trap period. These fast entangling gates should work outside of the Lamb-Dicke regime and be insensitive to thermal atomic motion.

  11. Atomic magnetometer for human magnetoencephalograpy.

    SciTech Connect (OSTI)

    Schwindt, Peter; Johnson, Cort N.

    2010-12-01T23:59:59.000Z

    We have developed a high sensitivity (<5 fTesla/{radical}Hz), fiber-optically coupled magnetometer to detect magnetic fields produced by the human brain. This is the first demonstration of a noncryogenic sensor that could replace cryogenic superconducting quantum interference device (SQUID) magnetometers in magnetoencephalography (MEG) and is an important advance in realizing cost-effective MEG. Within the sensor, a rubidium vapor is optically pumped with 795 laser light while field-induced optical rotations are measured with 780 nm laser light. Both beams share a single optical axis to maximize simplicity and compactness. In collaboration with neuroscientists at The Mind Research Network in Albuquerque, NM, the evoked responses resulting from median nerve and auditory stimulation were recorded with the atomic magnetometer and a commercial SQUID-based MEG system with signals comparing favorably. Multi-sensor operation has been demonstrated with two AMs placed on opposite sides of the head. Straightforward miniaturization would enable high-density sensor arrays for whole-head magnetoencephalography.

  12. Coherent cooling of atoms in a frequency-modulated standing laser wave: Wave function and stochastic trajectory approaches

    SciTech Connect (OSTI)

    Argonov, V. Yu., E-mail: argonov@poi.dvo.ru [Russian Academy of Sciences, Pacific Oceanological Institute (Russian Federation)

    2014-11-15T23:59:59.000Z

    The wave function of a moderately cold atom in a stationary near-resonant standing light wave delocalizes very fast due to wave packet splitting. However, we show that frequency modulation of the field can suppress packet splitting for some atoms whose specific velocities are in a narrow range. These atoms remain localized in a small space for a long time. We demonstrate and explain this effect numerically and analytically. We also demonstrate that the modulated field can not only trap but also cool the atoms. We perform a numerical experiment with a large atomic ensemble having wide initial velocity and energy distributions. During the experiment, most of atoms leave the wave while the trapped atoms have a narrow energy distribution.

  13. Scattering properties of dark atoms and molecules

    E-Print Network [OSTI]

    James M. Cline; Zuowei Liu; Guy D. Moore; Wei Xue

    2014-01-15T23:59:59.000Z

    There has been renewed interest in the possibility that dark matter exists in the form of atoms, analogous to those of the visible world. An important input for understanding the cosmological consequences of dark atoms is their self-scattering. Making use of results from atomic physics for the potentials between hydrogen atoms, we compute the low-energy elastic scattering cross sections for dark atoms. We find an intricate dependence upon the ratio of the dark proton to electron mass, allowing for the possibility to "design" low-energy features in the cross section. Dependences upon other parameters, namely the gauge coupling and reduced mass, scale out of the problem by using atomic units. We derive constraints on the parameter space of dark atoms by demanding that their scattering cross section does not exceed bounds from dark matter halo shapes. We discuss the formation of molecular dark hydrogen in the universe, and determine the analogous constraints on the model when the dark matter is predominantly in molecular form.

  14. Scattering properties of dark atoms and molecules

    E-Print Network [OSTI]

    Cline, James M; Moore, Guy; Xue, Wei

    2013-01-01T23:59:59.000Z

    There has been renewed interest in the possibility that dark matter exists in the form of atoms, analogous to those of the visible world. An important input for understanding the cosmological consequences of dark atoms is their self-scattering. Making use of results from atomic physics for the potentials between hydrogen atoms, we compute the low-energy elastic scattering cross sections for dark atoms. We find an intricate dependence upon the ratio of the dark proton to electron mass, allowing for the possibility to "design" low-energy features in the cross section. Dependences upon other parameters, namely the gauge coupling and reduced mass, scale out of the problem by using atomic units. We derive constraints on the parameter space of dark atoms by demanding that their scattering cross section does not exceed bounds from dark matter halo shapes. We discuss the formation of molecular dark hydrogen in the universe, and determine the analogous constraints on the model when the dark matter is predominantly in ...

  15. Ps-atom scattering at low energies

    E-Print Network [OSTI]

    Fabrikant, I I

    2015-01-01T23:59:59.000Z

    A pseudopotential for positronium-atom interaction, based on electron-atom and positron-atom phase shifts, is constructed, and the phase shifts for Ps-Kr and Ps-Ar scattering are calculated. This approach allows us to extend the Ps-atom cross sections, obtained previously in the impulse approximation [Phys. Rev. Lett. 112, 243201 (2014)], to energies below the Ps ionization threshold. Although experimental data are not available in this low-energy region, our results describe well the tendency of the measured cross sections to drop with decreasing velocity at $v<1$ a.u. Our results show that the effect of the Ps-atom van der Waals interaction is weak compared to the polarization interaction in electron-atom and positron-atom scattering. As a result, the Ps scattering length for both Ar and Kr is positive, and the Ramsauer-Townsend minimum is not observed for Ps scattering from these targets. This makes Ps scattering quite different from electron scattering in the low-energy region, in contrast to the inter...

  16. Studying coherence in ultra-cold atomic gases

    E-Print Network [OSTI]

    Miller, Daniel E. (Daniel Edward)

    2007-01-01T23:59:59.000Z

    This thesis will discuss the study of coherence properties of ultra-cold atomic gases. The atomic systems investigated include a thermal cloud of atoms, a Bose-Einstein condensate and a fermion pair condensate. In each ...

  17. Theory of ultracold atomic Fermi gases

    SciTech Connect (OSTI)

    Giorgini, Stefano; Pitaevskii, Lev P.; Stringari, Sandro [Dipartimento di Fisica, Universita di Trento and CNR-INFM BEC Center, I-38050 Povo, Trento (Italy); Dipartimento di Fisica, Universita di Trento and CNR-INFM BEC Center, I-38050 Povo, Trento, Italy and Kapitza Institute for Physical Problems, ul. Kosygina 2, 117334 Moscow (Russian Federation); Dipartimento di Fisica, Universita di Trento and CNR-INFM BEC Center, I-38050 Povo, Trento (Italy)

    2008-10-15T23:59:59.000Z

    The physics of quantum degenerate atomic Fermi gases in uniform as well as in harmonically trapped configurations is reviewed from a theoretical perspective. Emphasis is given to the effect of interactions that play a crucial role, bringing the gas into a superfluid phase at low temperature. In these dilute systems, interactions are characterized by a single parameter, the s-wave scattering length, whose value can be tuned using an external magnetic field near a broad Feshbach resonance. The BCS limit of ordinary Fermi superfluidity, the Bose-Einstein condensation (BEC) of dimers, and the unitary limit of large scattering length are important regimes exhibited by interacting Fermi gases. In particular, the BEC and the unitary regimes are characterized by a high value of the superfluid critical temperature, on the order of the Fermi temperature. Different physical properties are discussed, including the density profiles and the energy of the ground-state configurations, the momentum distribution, the fraction of condensed pairs, collective oscillations and pair-breaking effects, the expansion of the gas, the main thermodynamic properties, the behavior in the presence of optical lattices, and the signatures of superfluidity, such as the existence of quantized vortices, the quenching of the moment of inertia, and the consequences of spin polarization. Various theoretical approaches are considered, ranging from the mean-field description of the BCS-BEC crossover to nonperturbative methods based on quantum Monte Carlo techniques. A major goal of the review is to compare theoretical predictions with available experimental results.

  18. 1984 Bibliography of atomic and molecular processes

    SciTech Connect (OSTI)

    Barnett, C.F.; Gilbody, H.B.; Gregory, D.C.; Griffin, P.M.; Havener, C.C.; Howard, A.M.; Kirkpatrick, M.I.; McDaniel, E.W.; Meyer, F.W.; Morgan, T.J. (comps.)

    1985-04-01T23:59:59.000Z

    This annotated bibliography includes papers on atomic and molecular processes published during 1984. Sources include scientific journals, conference proceedings, and books. Each entry is designated by one or more of the 114 categories of atomic and molecular processes used by the Controlled Fusion Atomic Data Center, Oak Ridge National Laboratory to classify data. Also indicated is whether the work was experimental or theoretical, what energy range was covered, what reactants were investigated, and the country of origin of the first author. Following the bibliographical listing, the entries are indexed according to the categories and according to reactants within each subcategory.

  19. 1985 bibliography of atomic and molecular processes

    SciTech Connect (OSTI)

    Barnett, C.F.; Gilbody, H.B.; Gregory, D.C.; Griffin, P.M.; Havener, C.C.; Howald, A.M.; Kirkpatrick, M.I.; McDaniel, E.W.; Meyer, F.W.; Morgan, T.J. (comps.)

    1986-06-01T23:59:59.000Z

    This annotated bibliography includes papers on atomic and molecular processes published during 1985. Sources include scientific journals, conference proceedings, and books. Each entry is designated by one or more of the 114 categories of atomic and molecular processes used by the Controlled Fusion Atomic Data Center, Oak Ridge National Laboratory to classify data. Also indicated is whether the work was experimental or theoretical, what energy range was covered, what reactants were investigated, and the country of origin of the first author. Following the bibliographical listing, the entries are indexed according to the categories and according to reactants within each subcategory.

  20. Gain narrowing in few-atom systems

    E-Print Network [OSTI]

    Tom Savels; Allard P. Mosk; Ad Lagendijk

    2006-05-31T23:59:59.000Z

    Using a density matrix approach, we study the simplest systems that display both gain and feedback: clusters of 2 to 5 atoms, one of which is pumped. The other atoms supply feedback through multiple scattering of light. We show that, if the atoms are in each other's near-field, the system exhibits large gain narrowing and spectral mode redistribution. The observed phenomena are more pronounced if the feedback is enhanced. Our system is to our knowledge the simplest exactly solvable microscopic system which shows the approach to laser oscillation.

  1. Cold Light from Hot Atoms and Molecules

    SciTech Connect (OSTI)

    Lister, Graeme [OSRAM SYLVANIA, CRSL, 71 Cherry Hill Drive, Beverly, MA (United States); Curry, John J. [National Institute of Standards and Technology, Gaithersburg, MD (United States)

    2011-05-11T23:59:59.000Z

    The introduction of rare earth atoms and molecules into lighting discharges led to great advances in efficacy of these lamps. Atoms such as Dy, Ho and Ce provide excellent radiation sources for lighting applications, with rich visible spectra, such that a suitable combination of these elements can provide high quality white light. Rare earth molecules have also proved important in enhancing the radiation spectrum from phosphors in fluorescent lamps. This paper reviews some of the current aspects of lighting research, particularly rare earth chemistry and radiation, and the associated fundamental atomic and molecular data.

  2. The Manhattan Project: Making the atomic bomb

    SciTech Connect (OSTI)

    Gosling, F.G.

    1994-09-01T23:59:59.000Z

    This article is a short history of the origins and development of the American atomic bomb program during World War II. Beginning with the scientific developments of the pre-war years, the monograph details the role of US government in conducting a secret, nationwide enterprise that took science from the laboratory and into combat with an entirely new type of weapon. The monograph concludes with a discussion of the immediate postwar period, the debate over the Atomic Energy Act of 1946, and the founding of the Atomic Energy Commission.

  3. 1982 bibliography of atomic and molecular processes

    SciTech Connect (OSTI)

    Barnett, C.F.; Crandall, D.H.; Gilbody, H.B.; Gregory, D.C.; Kirkpatrick, M.I.; McDaniel, E.W.; McKnight, R.H.; Meyer, F.W.; Morgan, T.J.; Phaneuf, R.A. (comps.)

    1984-05-01T23:59:59.000Z

    This annotated bibliography includes papers on atomic and molecular processes published during 1982. Sources include scientific journals, conference proceedings, and books. Each entry is designated by one or more of the 114 categories of atomic and molecular processes used by the Controlled Fusion Atomic Data Center, Oak Ridge National Laboratory to classify data. Also indicated is whether the work was experimental or theoretical, what energy range was covered, what reactants were investigated, and the country of origin of the first author. Following the bibliographical listing, the entries are indexed according to the categories and according to reactants within each subcategory.

  4. Interaction of an aluminum atom with a closed subshell metal atom: Spectroscopic analysis of AlZn

    E-Print Network [OSTI]

    Morse, Michael D.

    Interaction of an aluminum atom with a closed subshell metal atom: Spectroscopic analysis of Al-block main group element, aluminum, and the 3d series of transi- tion metal atoms. Although the bonding in Al

  5. acoustic wave atomization: Topics by E-print Network

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

    of fluid and acoustic computations, hybrid methodologies still Kohlenbach, Ulrich 12 Propagation of atomic matter waves inside an atom wave guide Quantum Physics (arXiv)...

  6. atomic emission spectrometry: Topics by E-print Network

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

    not the direction of the atom's motion. The conclusion is also evident from a simple energy relation: atomic spectral radiation is emitted as an orbiting electron consumes a...

  7. Structure of ?-Alumina: Toward The Atomic Level Understanding...

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

    -Alumina: Toward The Atomic Level Understanding Of Transition Alumina Phases. Structure of -Alumina: Toward The Atomic Level Understanding Of Transition Alumina Phases....

  8. Atomic Energy Commission Explores Peaceful Uses of Nuclear Explosions...

    National Nuclear Security Administration (NNSA)

    Our Jobs Working at NNSA Blog Home About Us Our History NNSA Timeline Atomic Energy Commission Explores Peaceful Uses of ... Atomic Energy Commission Explores Peaceful...

  9. Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium...

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

    Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium-Nickel Nanoalloys. Atomic-Structural Synergy for Catalytic CO Oxidation over Palladium-Nickel Nanoalloys....

  10. atomic carbon nanowires: Topics by E-print Network

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

    Page Topic Index 1 Electron Transport Properties of Atomic Carbon Nanowires between Graphene Electrodes CERN Preprints Summary: Long, stable and free-standing linear atomic...

  11. Isolation, Characterization of an Intermediate in an Oxygen Atom...

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

    Characterization of an Intermediate in an Oxygen Atom-Transfer Reaction, and the Determination of the Bond Isolation, Characterization of an Intermediate in an Oxygen Atom-Transfer...

  12. Materials, Modules, and Systems: An Atoms to Autos Approach to...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Materials, Modules, and Systems: An Atoms to Autos Approach to Automotive Thermoelectric Systems Development Materials, Modules, and Systems: An Atoms to Autos Approach to...

  13. atomic number: Topics by E-print Network

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

    and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

  14. atomic number density: Topics by E-print Network

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

    and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Quantum Physics (arXiv) Summary: We study atom-atom correlations and relative...

  15. atomic mass number: Topics by E-print Network

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

    and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

  16. atomic number electron: Topics by E-print Network

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

    and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

  17. atom interferometry measurement: Topics by E-print Network

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

    Bose-condensed atoms . Open Access Theses and Dissertations Summary: ??Bose-Einstein condensates are coherent matter waves, produced by cooling gaseous atomic clouds to ultra-low...

  18. atomic wave packets: Topics by E-print Network

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

    Statistics of atomic populations in output coupled wave packets from Bose-Einstein condensates: Four-wave mixing Physics Websites Summary: Statistics of atomic populations in...

  19. atomic number range: Topics by E-print Network

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

    and relative number squeezing in dissociation of spatially inhomogeneous molecular condensates Physics Websites Summary: Atom-atom correlations and relative number squeezing in...

  20. atom interferometry progress: Topics by E-print Network

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

    Bose-condensed atoms . Open Access Theses and Dissertations Summary: ??Bose-Einstein condensates are coherent matter waves, produced by cooling gaseous atomic clouds to ultra-low...

  1. Adsorption of Atoms and Molecules Physisorption

    E-Print Network [OSTI]

    Glashausser, Charles

    Adsorption of Atoms and Molecules Physisorption Chemisorption Surface Bonding Kinetics of Adsorption/Diffusion/Desorption (Scattering Dynamics) #12;Outcomes of Collision Process Rebound (elastically or inelastically) Elastic Scattering Inelastic Scattering Accomodation (thermalizing) Adsorption E V(r) r

  2. Atomic physics: An almost lightless laser

    E-Print Network [OSTI]

    Vuletic, Vladan

    Lasers are often described in terms of a light field circulating in an optical resonator system. Now a laser has been demonstrated in which the field resides primarily in the atomic medium that is used to generate the light.

  3. FREQUENCY DEPENDENT MULTIPOLE POLARIZABILITIES OF ATOMIC SYSTEMS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1259 FREQUENCY DEPENDENT MULTIPOLE POLARIZABILITIES OF ATOMIC SYSTEMS S. I. EASA and G. C. SHUKLA et d'helium. Abstract. 2014 A variational calculation for frequency dependent multipole 1978, Classification Physics Abstracts 31.10 The calculation of multipole polarizabilities

  4. Electronic transport in atomically thin layered materials

    E-Print Network [OSTI]

    Baugher, Britton William Herbert

    2014-01-01T23:59:59.000Z

    Electronic transport in atomically thin layered materials has been a burgeoning field of study since the discovery of isolated single layer graphene in 2004. Graphene, a semi-metal, has a unique gapless Dirac-like band ...

  5. Accurate capacitive metrology for atomic force microscopy

    E-Print Network [OSTI]

    Mazzeo, Aaron D. (Aaron David), 1979-

    2005-01-01T23:59:59.000Z

    This thesis presents accurate capacitive sensing metrology designed for a prototype atomic force microscope (AFM) originally developed in the MIT Precision Motion Control Lab. The capacitive measurements use a set of ...

  6. Quantum Structures of the Hydrogen Atom

    E-Print Network [OSTI]

    J. Jeknic-Dugic; M. Dugic; A. Francom; M. Arsenijevic

    2014-05-28T23:59:59.000Z

    Modern quantum theory introduces quantum structures (decompositions into subsystems) as a new discourse that is not fully comparable with the classical-physics counterpart. To this end, so-called Entanglement Relativity appears as a corollary of the universally valid quantum mechanics that can provide for a deeper and more elaborate description of the composite quantum systems. In this paper we employ this new concept to describe the hydrogen atom. We offer a consistent picture of the hydrogen atom as an open quantum system that naturally answers the following important questions: (a) how do the so called "quantum jumps" in atomic excitation and de-excitation occur? and (b) why does the classically and seemingly artificial "center-of-mass + relative degrees of freedom" structure appear as the primarily operable form in most of the experimental reality of atoms?

  7. United Nations Atomic Energy Commission stalls out

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

    commission would be short-lived and would not result in the desired control of atomic energy. In the wake of the disappointing results of the Moscow meeting, the United States...

  8. Moving closer to the Atomic Energy Commission

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

    in some way. On October 3, 1945 the president addressed Congress on the subject of atomic energy. Here he first mentioned the need for international agreements. Attempts were made...

  9. Quantum micro-mechanics with ultracold atoms

    E-Print Network [OSTI]

    Thierry Botter; Daniel Brooks; Subhadeep Gupta; Zhao-Yuan Ma; Kevin L. Moore; Kater W. Murch; Tom P. Purdy; Dan M. Stamper-Kurn

    2008-10-21T23:59:59.000Z

    In many experiments isolated atoms and ions have been inserted into high-finesse optical resonators for the study of fundamental quantum optics and quantum information. Here, we introduce another application of such a system, as the realization of cavity optomechanics where the collective motion of an atomic ensemble serves the role of a moveable optical element in an optical resonator. Compared with other optomechanical systems, such as those incorporating nanofabricated cantilevers or the large cavity mirrors of gravitational observatories, our cold-atom realization offers direct access to the quantum regime. We describe experimental investigations of optomechanical effects, such as the bistability of collective atomic motion and the first quantification of measurement backaction for a macroscopic object, and discuss future directions for this nascent field.

  10. Remote-State Prparation eines einzelnen Atoms

    E-Print Network [OSTI]

    Weinfurter, Harald

    Remote-State Präparation eines einzelnen Atoms Diplomarbeit am Department für Physik der Ludwig . . . . . . . . . . . . . . . . . . . . . 8 1.3.3 Remote-State-Präparation . . . . . . . . . . . . . . . . . . . . . 11 1.3.4 Zusammenfassung . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 3 Remote-State-Präparation 31 3.1 Einleitung

  11. Electrical Analogs of Atomic Radiative Decay Processes

    E-Print Network [OSTI]

    Fontana, Peter R.; Srivastava, Rajendra P.

    1977-03-01T23:59:59.000Z

    Simple electrical circuits are analyzed, and the results show that for high frequencies they have frequency and time responses identical to the spontaneous radiative decays of atoms. As an illustration of the analogy a two-circuit electrical system...

  12. Atomic vapor spectroscopy in integrated photonic structures

    E-Print Network [OSTI]

    Ritter, Ralf; Pernice, Wolfram; Kübler, Harald; Pfau, Tilman; Löw, Robert

    2015-01-01T23:59:59.000Z

    We investigate an integrated optical chip immersed in atomic vapor providing several waveguide geometries for spectroscopy applications. The narrow-band transmission through a silicon nitride waveguide and interferometer is altered when the guided light is coupled to a vapor of rubidium atoms via the evanescent tail of the waveguide mode. We use grating couplers to couple between the waveguide mode and the radiating wave, which allow for addressing arbitrary coupling positions on the chip surface. The evanescent atom-light interaction can be numerically simulated and shows excellent agreement with our experimental data. This work demonstrates a next step towards miniaturization and integration of alkali atom spectroscopy and provides a platform for further fundamental studies of complex waveguide structures.

  13. Hydrogen atom in rotationally invariant noncommutative space

    E-Print Network [OSTI]

    Kh. P. Gnatenko; V. M. Tkachuk

    2014-11-03T23:59:59.000Z

    We consider the noncommutative algebra which is rotationally invariant. The hydrogen atom is studied in a rotationally invariant noncommutative space. We find the corrections to the energy levels of the hydrogen atom up to the second order in the parameter of noncommutativity. The upper bound of the parameter of noncommutativity is estimated on the basis of the experimental results for 1s-2s transition frequency.

  14. Atomic resolution images of graphite in air

    SciTech Connect (OSTI)

    Grigg, D.A.; Shedd, G.M.; Griffis, D.; Russell, P.E.

    1988-12-01T23:59:59.000Z

    One sample used for proof of operation for atomic resolution in STM is highly oriented pyrolytic graphite (HOPG). This sample has been imaged with many different STM`s obtaining similar results. Atomic resolution images of HOPG have now been obtained using an STM designed and built at the Precision Engineering Center. This paper discusses the theoretical predictions and experimental results obtained in imaging of HOPG.

  15. Controlling the Ratchet Effect for Cold Atoms

    E-Print Network [OSTI]

    Anatole Kenfack; Jiangbin Gong; Arjendu K. Pattanayak

    2007-11-27T23:59:59.000Z

    Low-order quantum resonances manifested by directed currents have been realized with cold atoms. Here we show that by increasing the strength of an experimentally achievable delta-kicking ratchet potential, quantum resonances of a very high order may naturally emerge and can induce larger ratchet currents than low-order resonances, with the underlying classical limit being fully chaotic. The results offer a means of controlling quantum transport of cold atoms.

  16. ac-driven atomic quantum motor

    E-Print Network [OSTI]

    A. V. Ponomarev; S. Denisov; P. Hanggi

    2009-06-09T23:59:59.000Z

    We invent an ac-driven quantum motor consisting of two different, interacting ultracold atoms placed into a ring-shaped optical lattice and submerged in a pulsating magnetic field. While the first atom carries a current, the second one serves as a quantum starter. For fixed zero-momentum initial conditions the asymptotic carrier velocity converges to a unique non-zero value. We also demonstrate that this quantum motor performs work against a constant load.

  17. From Lattice Gauge Theories to Hydrogen Atoms

    E-Print Network [OSTI]

    Manu Mathur; T. P. Sreeraj

    2014-10-13T23:59:59.000Z

    Using canonical transformations we obtain a complete and most economical realization of the loop or physical Hilbert space of pure $SU(2)_{2+1}$ lattice gauge theory in terms of Wigner coupled Hilbert spaces of hydrogen atoms. One hydrogen atom is assigned to every plaquette of the lattice. The SU(2) gauge theory loop basis states over a plaquette are the bound energy eigenstates $|n l m>$ of the corresponding hydrogen atom. The Wigner couplings of these hydrogen atom energy eigenstates on different plaquettes provide a complete SU(2) gauge theory loop basis on the entire lattice. The loop basis is invariant under simultaneous rotations of all hydrogen atoms. The dual description of this basis diagonalizes all Wilson loop operators and is given in terms of hyperspherical harmonics on the SU(2) group manifold $S^3$. The SU(2) loop dynamics is governed by a "SU(2) spin Hamiltonian" without any gauge fields. The relevance of the hydrogen atom basis and its dynamical symmetry group SO(4,2) in SU(2) loop dynamics in weak coupling continuum limit ($g^2\\rightarrow 0$) is emphasized.

  18. Excess optical quantum noise in atomic sensors

    E-Print Network [OSTI]

    Irina Novikova; Eugeniy E. Mikhailov; Yanhong Xiao

    2014-10-14T23:59:59.000Z

    Enhanced nonlinear optical response of a coherent atomic medium is the basis for many atomic sensors, and their performance is ultimately limited by the quantum fluctuations of the optical read-out. Here we demonstrate that off-resonant interactions can significantly modify the quantum noise of the optical field, even when their effect on the mean signal is negligible. We illustrate this concept by using an atomic magnetometer based on the nonlinear Faraday effect: the rotation of the light polarization is mainly determined by the resonant light-induced spin alignment, which alone does not change the photon statistics of the optical probe. Yet, we found that the minimum noise of output polarization rotation measurements is above the expected shot noise limit. This excess quantum noise is due to off-resonant coupling and grows with atomic density. We also show that the detection scheme can be modified to reduce the measured quantum noise (even below the shot-noise limit) but only at the expense of the reduced rotational sensitivity. These results show the existence of previously unnoticed factors in fundamental limitations in atomic magnetometry and could have impacts in many other atom-light based precision measurements.

  19. Atoms 2014, 2, 157-177; doi:10.3390/atoms2020157 OPEN ACCESS

    E-Print Network [OSTI]

    Atoms 2014, 2, 157-177; doi:10.3390/atoms2020157 OPEN ACCESS atomsISSN 2218-2004 www]: = ne2 ¯h2 - dt1 t1 - dt2E(t1)·E(t2)ei (t1-t2) (3) where E(t1)·E(t2) = 2 3 0 vf(v)dv max 0 dE(t1

  20. Optomechanical Rydberg-atom excitation via dynamic Casimir-Polder coupling

    E-Print Network [OSTI]

    Mauro Antezza; Caterina Braggio; Giovanni Carugno; Antonio Noto; Roberto Passante; Lucia Rizzuto; Giuseppe Ruoso; Salvatore Spagnolo

    2014-07-09T23:59:59.000Z

    We study the optomechanical coupling of a oscillating effective mirror with a Rydberg atomic gas, mediated by the dynamical atom-mirror Casimir-Polder force. This coupling may produce a near-field resonant atomic excitation whose probability scales as $\\propto (d^2\\;a\\;n^4\\;t)^2/z_0^8$, where $z_0$ is the average atom-surface distance, $d$ the atomic dipole moment, $a$ the mirror's effective oscillation amplitude, $n$ the initial principal quantum number, and $t$ the time. We propose an experimental configuration to realize this system with a cold atom gas trapped at a distance $\\sim 2\\cdot10 \\, \\mu$m from a semiconductor substrate, whose dielectric constant is periodically driven by an external laser pulse, hence realizing en effective mechanical mirror motion due to the periodic change of the substrate from transparent to reflecting. For a parabolic gas shape, this effect is predicted to excite about $\\sim 10^2$ atoms of a dilute gas of $10^3$ trapped Rydberg atoms with $n=75$ after about $0.5 \\,\\mu \\mbox{s}$, hence high enough to be detected in typical Rydberg gas experimental conditions.

  1. Atoms for peace and war, 1953-1961: Eisenhower and the Atomic Energy Commission

    SciTech Connect (OSTI)

    Hewlett, Richard G.; Holl, Jack M.

    1989-12-01T23:59:59.000Z

    This third volume in the official history of the U.S. Atomic Energy Commission covers the years of the Eisenhower Administration.

  2. Surface trap for ytterbium ions

    E-Print Network [OSTI]

    Campbell, Jonathan A. (Jonathan Alan)

    2006-01-01T23:59:59.000Z

    We conducted an experiment to load a shallow planar ion trap from a cold atom source of Ytterbium using photoionization. The surface trap consisted of a three-rod radio frequency Paul trap fabricated using standard printed ...

  3. arXiv:0708.4197v1[cond-mat.other]30Aug2007 Optimal transport of ultracold atoms in the non-adiabatic regime

    E-Print Network [OSTI]

    Guéry-Odelin, David

    with ultracold atoms by moving slowly optical tweezers [3]. Transport of cold packets of atoms is also addressed numer- ically for ions in Paul traps [14]. In this article, we re- port on the transport of a coldarXiv:0708.4197v1[cond-mat.other]30Aug2007 Optimal transport of ultracold atoms in the non

  4. 29Counting Atoms in a Molecule The complex molecule Propanal

    E-Print Network [OSTI]

    29Counting Atoms in a Molecule The complex molecule Propanal was discovered in a dense interstellar is the ratio of carbon atoms to hydrogen atoms in propanal? Problem 4 - If the mass of a hydrogen atom of a propanal molecule in AMUs? Problem 5 - What is the complete chemical formula for propanal? C3 H __ O

  5. ATOMIC PHYSICS DMITRY BUDKER | DEREK F. KIMBALL | DAVID P. DEMILLE

    E-Print Network [OSTI]

    Pines, Alexander

    symmetries, atomic magnetometers and frequency comb metrology with ultra-short laser pulses. Dmitry Budker

  6. Isolating and moving single atoms using silicon nanocrystals

    DOE Patents [OSTI]

    Carroll, Malcolm S. (Albuquerque, NM)

    2010-09-07T23:59:59.000Z

    A method is disclosed for isolating single atoms of an atomic species of interest by locating the atoms within silicon nanocrystals. This can be done by implanting, on the average, a single atom of the atomic species of interest into each nanocrystal, and then measuring an electrical charge distribution on the nanocrystals with scanning capacitance microscopy (SCM) or electrostatic force microscopy (EFM) to identify and select those nanocrystals having exactly one atom of the atomic species of interest therein. The nanocrystals with the single atom of the atomic species of interest therein can be sorted and moved using an atomic force microscope (AFM) tip. The method is useful for forming nanoscale electronic and optical devices including quantum computers and single-photon light sources.

  7. Atomic-level imaging, processing and characterization of semiconductor surfaces

    DOE Patents [OSTI]

    Kazmerski, L.L.

    1995-08-22T23:59:59.000Z

    A method for selecting and removing single specific atoms from a solid material surface uses photon biasing to break down bonds that hold the selected atom in the lattice and to reduce barrier effects that hold the atom from transferring to a probe. The photon bias is preferably light or other electromagnetic radiation with a wavelength and frequency that approximately matches the wave function of the target atom species to be removed to induce high energy, selective thermionic-like vibration. An electric field potential is then applied between the probe and the surface of the solid material to pull the atom out of the lattice and to transfer the atom to the probe. Different extrinsic atoms can be installed in the lattice sites that are vacated by the removed atoms by using a photon bias that resonates the extrinsic atom species, reversing polarity of the electric field, and blowing gas comprising the extrinsic atoms through a hollow catheter probe. 8 figs.

  8. Atomic-level imaging, processing and characterization of semiconductor surfaces

    DOE Patents [OSTI]

    Kazmerski, Lawrence L. (Lakewood, CO)

    1995-01-01T23:59:59.000Z

    A method for selecting and removing single specific atoms from a solid material surface uses photon biasing to break down bonds that hold the selected atom in the lattice and to reduce barrier effects that hold the atom from transferring to a probe. The photon bias is preferably light or other electromagnetic radiation with a wavelength and frequency that approximately matches the wave function of the target atom species to be removed to induce high energy, selective thermionic-like vibration. An electric field potential is then applied between the probe and the surface of the solid material to pull the atom out of the lattice and to transfer the atom to the probe. Different extrinsic atoms can be installed in the lattice sites that are vacated by the removed atoms by using a photon bias that resonates the extrinsic atom species, reversing polarity of the electric field, and blowing gas comprising the extrinsic atoms through a hollow catheter probe.

  9. Hydrogen atom in de Sitter spaces

    E-Print Network [OSTI]

    O. V. Veko; K. V. Kazmerchuk; E. M. Ovsiyuk; V. M. Red'kov; A. M. Ishkhanyan

    2014-12-28T23:59:59.000Z

    The hydrogen atom theory is developed for the de Sitter and anti de Sitter spaces on the basis of the Klein-Gordon-Fock wave equation in static coordinates. In both models, after separation of the variables, the problem is reduced to the general Heun equation, a second order linear differential equation having four regular singular points. A qualitative examination shows that the energy spectrum for the hydrogen atom in the de Sitter space should be quasi-stationary, and the atom should be unstable. We derive an approximate expression for energy levels within the quasi-classical approach and estimate the probability of decay of the atom. A similar analysis shows that in the anti de Sitter model the hydrogen atom should be stable in the quantum-mechanical sense. Using the quasi-classical approach, we derive approximate formulas for energy levels for this case as well. Finally, we present the extension to the case of a spin 1/2 particle for both de Sitter models. This extension leads to complicated differential equations with 8 singular points.

  10. Method and apparatus for atomic imaging

    DOE Patents [OSTI]

    Saldin, Dilano K. (Milwaukee, WI); de Andres Rodriquez, Pedro L. (Madrid, ES)

    1993-01-01T23:59:59.000Z

    A method and apparatus for three dimensional imaging of the atomic environment of disordered adsorbate atoms are disclosed. The method includes detecting and measuring the intensity of a diffuse low energy electron diffraction pattern formed by directing a beam of low energy electrons against the surface of a crystal. Data corresponding to reconstructed amplitudes of a wave form is generated by operating on the intensity data. The data corresponding to the reconstructed amplitudes is capable of being displayed as a three dimensional image of an adsorbate atom. The apparatus includes a source of a beam of low energy electrons and a detector for detecting the intensity distribution of a DLEED pattern formed at the detector when the beam of low energy electrons is directed onto the surface of a crystal. A device responsive to the intensity distribution generates a signal corresponding to the distribution which represents a reconstructed amplitude of a wave form and is capable of being converted into a three dimensional image of the atomic environment of an adsorbate atom on the crystal surface.

  11. Dynamic polarizabilities of rare-earth-metal atoms and dispersion coefficients for their interaction with helium atoms

    E-Print Network [OSTI]

    Chu, Xi

    Dynamic polarizabilities of rare-earth-metal atoms and dispersion coefficients; published 29 March 2007 The dynamic scalar and tensor polarizabilities of the rare-earth-metal atoms coefficients for the interactions of the rare-earth-metal atoms with helium atoms. The static polarizabilities

  12. Optical pumping of a lithium atomic beam for atom interferometry J. Gillot, A. Gauguet, M. Buchner, and J. Vigue

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Optical pumping of a lithium atomic beam for atom interferometry J. Gillot, A. Gauguet, M. B.vigue@irsamc.ups-tlse.fr (Dated: May 29, 2013) We apply optical pumping to prepare the lithium beam of our atom interferometer in a single hyperfine-Zeeman sublevel: we use two components of the D1-line for pumping the 7 Li atoms

  13. Atomic Scale Characterization of Compound Semiconductors using Atom Probe Tomography: Preprint

    SciTech Connect (OSTI)

    Gorman, B. P.; Guthrey, H.; Norman, A. G.; Al-Jassim, M.; Lawrence, D.; Prosa, T.

    2011-07-01T23:59:59.000Z

    Internal interfaces are critical in determining the performance of III-V multijunction solar cells. Studying these interfaces with atomic resolution using a combination of transmission electron microscopy (TEM), atom probe tomography (APT), and density functional calculations enables a more fundamental understanding of carrier dynamics in photovoltaic (PV) device structures. To achieve full atomic scale spatial and chemical resolution, data acquisition parameters in laser pulsed APT must be carefully studied to eliminate surface diffusion. Atom probe data with minimized group V ion clustering and expected stoichiometry can be achieved by adjusting laser pulse power, pulse repetition rate, and specimen preparation parameters such that heat flow away from the evaporating surface is maximized. Applying these improved analysis conditions to III-V based PV gives an atomic scale understanding of compositional and dopant profiles across interfaces and tunnel junctions and the initial stages of alloy clustering and dopant accumulation. Details on APT experimental methods and future in-situ instrumentation developments are illustrated.

  14. Cavity Nonlinear Optics at Low Photon Numbers from Collective Atomic Motion

    E-Print Network [OSTI]

    Subhadeep Gupta; Kevin L. Moore; Kater W. Murch; Dan M. Stamper-Kurn

    2007-09-05T23:59:59.000Z

    We report on Kerr nonlinearity and dispersive optical bistability of a Fabry-Perot optical resonator due to the displacement of ultracold atoms trapped within. In the driven resonator, such collective motion is induced by optical forces acting upon up to $10^5$ $^{87}$Rb atoms prepared in the lowest band of a one-dimensional intracavity optical lattice. The longevity of atomic motional coherence allows for strongly nonlinear optics at extremely low cavity photon numbers, as demonstrated by the observation of both branches of optical bistability at photon numbers below unity.

  15. Atomic multipole relaxation rates near surfaces

    E-Print Network [OSTI]

    J. A. Crosse; Stefan Scheel

    2010-08-13T23:59:59.000Z

    The spontaneous relaxation rates for an atom in free space and close to an absorbing surface are calculated to various orders of the electromagnetic multipole expansion. The spontaneous decay rates for dipole, quadrupole and octupole transitions are calculated in terms of their respective primitive electric multipole moments and the magnetic relaxation rate is calculated for the dipole and quadrupole transitions in terms of their respective primitive magnetic multipole moments. The theory of electromagnetic field quantization in magnetoelectric materials is used to derive general expressions for the decay rates in terms of the dyadic Green function. We focus on the decay rates in free space and near an infinite half space. For the decay of atoms near to an absorbing dielectric surface we find a hierarchy of scaling laws depending on the atom-surface distance z.

  16. Atomic Rydberg Reservoirs for Polar Molecules

    E-Print Network [OSTI]

    Zhao, Bo; Pupillo, Guido; Zoller, Peter

    2011-01-01T23:59:59.000Z

    We discuss laser dressed dipolar and Van der Waals interactions between atoms and polar molecules, so that a cold atomic gas with laser admixed Rydberg levels acts as a designed reservoir for both elastic and inelastic collisional processes. The elastic scattering channel is characterized by large elastic scattering cross sections and repulsive shields to protect from close encounter collisions. In addition, we discuss a dissipative (inelastic) collision where a spontaneously emitted photon carries away (kinetic) energy of the collision partners, thus providing a significant energy loss in a single collision. This leads to the scenario of rapid thermalization and cooling of a molecule in the mK down to the \\mu K regime by cold atoms.

  17. Atomic Rydberg Reservoirs for Polar Molecules

    E-Print Network [OSTI]

    Bo Zhao; Alexander Glätzle; Guido Pupillo; Peter Zoller

    2011-12-18T23:59:59.000Z

    We discuss laser dressed dipolar and Van der Waals interactions between atoms and polar molecules, so that a cold atomic gas with laser admixed Rydberg levels acts as a designed reservoir for both elastic and inelastic collisional processes. The elastic scattering channel is characterized by large elastic scattering cross sections and repulsive shields to protect from close encounter collisions. In addition, we discuss a dissipative (inelastic) collision where a spontaneously emitted photon carries away (kinetic) energy of the collision partners, thus providing a significant energy loss in a single collision. This leads to the scenario of rapid thermalization and cooling of a molecule in the mK down to the \\mu K regime by cold atoms.

  18. Searching for dark matter with helium atom

    E-Print Network [OSTI]

    Imre Ferenc Barna

    2006-08-10T23:59:59.000Z

    With the help of the boost operator we can model the interaction between a weakly interacting particle(WIMP) of dark matter(DAMA) and an atomic nuclei. Via this "kick" we calculate the total electronic excitation cross section of the helium atom. The bound spectrum of He is calculated through a diagonalization process with a configuration interaction (CI) wavefunction built up from Slater orbitals. All together 19 singly- and doubly-excited atomic sates were taken with total angular momenta of L=0,1 and 2. Our calculation may give a rude estimation about the magnitude of the total excitation cross section which could be measured in later scintillator experiments. The upper limit of the excitation cross section is $9.7\\cdot 10^{-8}$ barn.

  19. Atom Interferometers and the Gravitational Redshift

    E-Print Network [OSTI]

    Supurna Sinha; Joseph Samuel

    2011-05-16T23:59:59.000Z

    From the principle of equivalence, Einstein predicted that clocks slow down in a gravitational field. Since the general theory of relativity is based on the principle of equivalence, it is essential to test this prediction accurately. Muller, Peters and Chu claim that a reinterpretation of decade old experiments with atom interferometers leads to a sensitive test of this gravitational redshift effect at the Compton frequency. Wolf et al dispute this claim and adduce arguments against it. In this article, we distill these arguments to a single fundamental objection: an atom is NOT a clock ticking at the Compton frequency. We conclude that atom interferometry experiments conducted to date do not yield such sensitive tests of the gravitational redshift. Finally, we suggest a new interferometric experiment to measure the gravitational redshift, which realises a quantum version of the classical clock "paradox".

  20. New charge radius relations for atomic nuclei

    E-Print Network [OSTI]

    B. H. Sun; Y. Lu; J. P. Peng; C. Y. Liu; Y. M. Zhao

    2014-11-24T23:59:59.000Z

    We show that the charge radii of neighboring atomic nuclei, independent of atomic number and charge, follow remarkably very simple relations, despite the fact that atomic nuclei are complex finite many-body systems governed by the laws of quantum mechanics. These relations can be understood within the picture of independent-particle motion and by assuming neighboring nuclei having similar pattern in the charge density distribution. A root-mean-square (rms) deviation of 0.0078 fm is obtained between the predictions in these relations and the experimental values, i.e., a comparable precision as modern experimental techniques. Such high accuracy relations are very useful to check the consistence of nuclear charge radius surface and moreover to predict unknown nuclear charge radii, while large deviations from experimental data is seen to reveal the appearance of nuclear shape transition or coexsitence.

  1. Proton Mass Shift in Muonic Hydrogen Atom

    E-Print Network [OSTI]

    Aiichi Iwazaki

    2014-08-11T23:59:59.000Z

    We show that the value of the proton mass depends on each bound state of muonic or electronic hydrogen atom. The charged particle bound to the proton produces magnetic field inside the proton. This makes a change to the amount of chiral condensate inside the proton. The change gives rise to the shift in the value of the proton mass. Numerically, the shift in the $2S$ state of the muonic hydrogen atom can be of the order of $0.1$ meV. The effect may solve the puzzle of the proton radius.

  2. Magnetic field imaging with atomic Rb vapor

    E-Print Network [OSTI]

    Eugeniy E. Mikhailov; I. Novikova; M. D. Havey; F. A. Narducci

    2009-07-27T23:59:59.000Z

    We demonstrate the possibility of dynamic imaging of magnetic fields using electromagnetically induced transparency in an atomic gas. As an experimental demonstration we employ an atomic Rb gas confined in a glass cell to image the transverse magnetic field created by a long straight wire. In this arrangement, which clearly reveals the essential effect, the field of view is about 2 x 2 mm^2 and the field detection uncertainty is 0.14 mG per 10 um x 10 um image pixel.

  3. Optical method of atomic ordering estimation

    SciTech Connect (OSTI)

    Prutskij, T. [Instituto de Ciencias, BUAP, Privada 17 Norte, No 3417, col. San Miguel Huyeotlipan, Puebla, Pue. (Mexico); Attolini, G. [IMEM/CNR, Parco Area delle Scienze 37/A - 43010, Parma (Italy); Lantratov, V.; Kalyuzhnyy, N. [Ioffe Physico-Technical Institute, 26 Polytekhnicheskaya, St Petersburg 194021, Russian Federation (Russian Federation)

    2013-12-04T23:59:59.000Z

    It is well known that within metal-organic vapor-phase epitaxy (MOVPE) grown semiconductor III-V ternary alloys atomically ordered regions are spontaneously formed during the epitaxial growth. This ordering leads to bandgap reduction and to valence bands splitting, and therefore to anisotropy of the photoluminescence (PL) emission polarization. The same phenomenon occurs within quaternary semiconductor alloys. While the ordering in ternary alloys is widely studied, for quaternaries there have been only a few detailed experimental studies of it, probably because of the absence of appropriate methods of its detection. Here we propose an optical method to reveal atomic ordering within quaternary alloys by measuring the PL emission polarization.

  4. Probing Dark Energy with Atom Interferometry

    E-Print Network [OSTI]

    Clare Burrage; Edmund J. Copeland; E. A. Hinds

    2014-08-06T23:59:59.000Z

    Theories of dark energy require a screening mechanism to explain why the associated scalar fields do not mediate observable long range fifth forces. The archetype of this is the chameleon field. Here we show that individual atoms are too small to screen the chameleon field inside a large high-vacuum chamber, and therefore can detect the field with high sensitivity. We derive new limits on the chameleon parameters from existing experiments, and show that most of the remaining chameleon parameter space is readily accessible using atom interferometry.

  5. AtomsPeace_Dec2003.qxd

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProductsAlternativeOperational ManagementDemand ModuleNationalAtomic,Atoms for

  6. Optimized coupling of cold atoms into a fiber using a blue-detuned hollow-beam funnel

    SciTech Connect (OSTI)

    Poulin, Jerome; Light, Philip S.; Kashyap, Raman; Luiten, Andre N. [Frequency Standards and Metrology Group, School of Physics, University of Western Australia, Western Australia 6009, Perth (Australia); Department of Engineering Physics, Ecole Polytechnique de Montreal, Montreal, Quebec, Canada H3C 3A7 (Canada); Frequency Standards and Metrology, School of Physics, University of Western Australia, Western Australia 6009, Perth (Australia)

    2011-11-15T23:59:59.000Z

    We theoretically investigate the process of coupling cold atoms into the core of a hollow-core photonic-crystal optical fiber using a blue-detuned Laguerre-Gaussian beam. In contrast to the use of a red-detuned Gaussian beam to couple the atoms, the blue-detuned hollow beam can confine cold atoms to the darkest regions of the beam, thereby minimizing shifts in the internal states and making the guide highly robust to heating effects. This single optical beam is used as both a funnel and a guide to maximize the number of atoms into the fiber. In the proposed experiment, Rb atoms are loaded into a magneto-optical trap (MOT) above a vertically oriented optical fiber. We observe a gravito-optical trapping effect for atoms with high orbital momentum around the trap axis, which prevents atoms from coupling to the fiber: these atoms lack the kinetic energy to escape the potential and are thus trapped in the laser funnel indefinitely. We find that by reducing the dipolar force to the point at which the trapping effect just vanishes, it is possible to optimize the coupling of atoms into the fiber. Our simulations predict that by using a low-power (2.5 mW) and far-detuned (300 GHz) Laguerre-Gaussian beam with a 20-{mu}m-radius core hollow fiber, it is possible to couple 11% of the atoms from a MOT 9 mm away from the fiber. When the MOT is positioned farther away, coupling efficiencies over 50% can be achieved with larger core fibers.

  7. Atomically localized plasmon enhancement in monolayer graphene

    E-Print Network [OSTI]

    Pennycook, Steve

    Atomically localized plasmon enhancement in monolayer graphene Wu Zhou1,2 *, Jaekwang Lee1,2 , Jagjit Nanda2 , Sokrates T. Pantelides1,2 , Stephen J. Pennycook1,2 and Juan-Carlos Idrobo1,2 * Plasmons plas- mons in very small regions could have applications in optoelec- tronics8,9 , plasmonics10

  8. Danish Atomic Energy Commission Research Establishment Riso

    E-Print Network [OSTI]

    roquott frem: Library of tho DmMi Atomic Enorgy Commlwton (AtornonorglkomrniMtonwM BtoHotok), RioA, DK, impregnated with four types of plastic, poly(methylmethacrylate), polyCstyrene/acrylonitril), polyester twice as much as conventional Danish face Btrip parquet flooring. Available on request from the Library

  9. Spectroscopic measurement of an atomic wave function

    E-Print Network [OSTI]

    Kapale, KT; Qamar, S.; Zubairy, M. Suhail.

    2003-01-01T23:59:59.000Z

    classical standing light, yields information about the position and momentum distribution of the atom [A. M. Herkommer, W. P. Schleich, and M. S. Zubairy, J. Mod. Opt. 44, 2507 (1997)]. In this paper, we show that both the amplitude and phase information...

  10. Stark spectroscopy on rare gas atoms

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    Technische Universiteit Eindhoven, op gezag van de Rector Magnificus, prof.dr.ir. C.J. van Duijn, voor een-DATA LIBRARY TECHNISCHE UNIVERSITEIT EINDHOVEN Jiang, Tao Stark spectroscopy on rare gas atoms / by Tao Jiang.-Eindhoven : Technische Universiteit Eindhoven, 2006. - Proefschrift. ISBN-10:90-386-2122-1 ISBN-13:978-90-386-2122-7 NUR

  11. Instead of splitting the atom --the

    E-Print Network [OSTI]

    gravitational forces ram hydrogen atoms together to produce helium, with solar energy the byproduct. On Earth -- with helium as the waste product in addition to the energy. A huge jolt of heat (to nearly 100 million C, 180 million F) would kickstart the process, fusing the nuclei in a charged gas called a plasma. Plasma has

  12. Nano-soldering to single atomic layer

    DOE Patents [OSTI]

    Girit, Caglar O. (Berkeley, CA); Zettl, Alexander K. (Kensington, CA)

    2011-10-11T23:59:59.000Z

    A simple technique to solder submicron sized, ohmic contacts to nanostructures has been disclosed. The technique has several advantages over standard electron beam lithography methods, which are complex, costly, and can contaminate samples. To demonstrate the soldering technique graphene, a single atomic layer of carbon, has been contacted, and low- and high-field electronic transport properties have been measured.

  13. Testing Time Reversal Symmetry in Artificial Atoms

    E-Print Network [OSTI]

    Frederico Brito; Francisco Rouxinol; M. D. LaHaye; Amir O. Caldeira

    2014-06-27T23:59:59.000Z

    Over the past several decades, a rich series of experiments has repeatedly verified the quantum nature of superconducting devices, leading some of these systems to be regarded as artificial atoms. In addition to their application in quantum information processing, these `atoms' provide a test bed for studying quantum mechanics in macroscopic limits. Regarding the last point, we present here a feasible protocol for directly testing time reversal symmetry in a superconducting artificial atom. Time reversal symmetry is a fundamental property of quantum mechanics and is expected to hold if the dynamics of the artificial atom strictly follow the Schroedinger equation. However, this property has yet to be tested in any macroscopic quantum system. The test we propose is based on the verification of the microreversibility principle, providing a viable approach to verify quantum work fluctuation theorems - an outstanding challenge in quantum statistical mechanics. For this, we outline a procedure that utilizes the microreversibility test in conjunction with numerical emulations of Gibbs ensembles to verify these theorems over a large temperature range.

  14. The New Element Curium (Atomic Number 96)

    DOE R&D Accomplishments [OSTI]

    Seaborg, G. T.; James, R. A.; Ghiorso, A.

    1948-00-00T23:59:59.000Z

    Two isotopes of the element with atomic number 96 have been produced by the helium-ion bombardment of plutonium. The name curium, symbol Cm, is proposed for element 96. The chemical experiments indicate that the most stable oxidation state of curium is the III state.

  15. Atomic-vapor-laser isotope separation

    SciTech Connect (OSTI)

    Davis, J.I.

    1982-10-01T23:59:59.000Z

    This paper gives a brief history of the scientific considerations leading to the development of laser isotope separation (LIS) processes. The close relationship of LIS to the broader field of laser-induced chemical processes is evaluated in terms of physical criteria to achieve an efficient production process. Atomic-vapor LIS processes under development at Livermore are reviwed. 8 figures.

  16. Table of hyperfine anomaly in atomic systems

    SciTech Connect (OSTI)

    Persson, J.R., E-mail: jonas.persson@ntnu.no

    2013-01-15T23:59:59.000Z

    This table is a compilation of experimental values of magnetic hyperfine anomaly in atomic and ionic systems. The last extensive compilation was published in 1984 by Büttgenbach [S. Büttgenbach, Hyperfine Int. 20 (1984) 1] and the aim here is to make an up to date compilation. The literature search covers the period up to January 2011.

  17. Quantum search protocol for an atomic array

    E-Print Network [OSTI]

    Scully, Marlan O.; Zubairy, M. Suhail

    2001-01-01T23:59:59.000Z

    without inversion @6#, 1050-2947/2001/64~2!/022304~5!/$20.00 64 022304- l for an atomic array M. Suhail Zubairy1,3 y, College Station, Texas 77843-4242 , 85748 Garching, Germany m University, Islamabad, Pakistan published 5 July 2001! d of ordinary...

  18. Atomic power in space: A history

    SciTech Connect (OSTI)

    Not Available

    1987-03-01T23:59:59.000Z

    ''Atomic Power in Space,'' a history of the Space Isotope Power Program of the United States, covers the period from the program's inception in the mid-1950s through 1982. Written in non-technical language, the history is addressed to both the general public and those more specialized in nuclear and space technologies. 19 figs., 3 tabs.

  19. AVIO: DETECTING ATOMICITY VIOLATIONS VIA ACCESS-

    E-Print Network [OSTI]

    Zhou, Yuanyuan

    detect some race bugs in concurrent programs, they have several limitations. First, what programmers ..................................................................................................................................................................................................................................................... THIS ARTICLE PROPOSES AN INNOVATIVE CONCURRENT-PROGRAM INVARIANT THAT CAPTURES PROGRAMMERS' ATOMICITY software bugs, concurrency bugs in multithreaded and multiprocess programs are among the most difficult

  20. The atom completed and a new particle

    E-Print Network [OSTI]

    Murayama, Hitoshi

    rules like the Balmer formula for the hydrogen atom. Cathode rays had been studied, but many regarded for the opportunity to have their hands x-rayed, and soon x rays were put to less frivolous uses in medical diagnosis found empirically a functional form for the energy spectrum that satisfied both theoretical principles

  1. Unusual condensates in quark and atomic systems

    E-Print Network [OSTI]

    B. Kerbikov

    2005-10-31T23:59:59.000Z

    In these lectures we discuss condensates which are formed in quark matter when it is squeezed and in a gas of fermionic atoms when it is cooled. The behavior of these two seemingly very different systems reveals striking similarities. In particular, in both systems the Bose-Einstein condensate to Bardeen--Cooper-Schrieffer (BEC-BCS) crossover takes place.

  2. ATOMIC IONIZATION AND OPACITIES IN PULSAR ATMOSPHERES

    E-Print Network [OSTI]

    ATOMIC IONIZATION AND OPACITIES IN PULSAR ATMOSPHERES Hydrogen Atmospheres J. VENTURA Physics.g. Pavlov et al., 1995; Zavlin et al., 1995, 1996; #12; 2 J. VENTURA ET AL. Rajagopal and Romani, 1996 the past three years. As is well known (Canuto and Ventura, 1977; Ruder et al., 1994), the external strong

  3. A Calculus of Atomic Actions Tayfun Elmas

    E-Print Network [OSTI]

    Tasiran, Serdar

    the sequential properties or the concurrency control mechanisms in the program. We implemented our method of assertions and procedure specifications in shared-memory con- current programs. The key idea in our approach is to use atom- icity as a proof tool and to simplify the verification of assertions by rewriting programs

  4. DEVELOPMENT OF A LOW PRESSURE, AIR ATOMIZED OIL BURNER WITH HIGH ATOMIZER AIR FLOW

    SciTech Connect (OSTI)

    BUTCHER,T.A.

    1998-01-01T23:59:59.000Z

    This report describes technical advances made to the concept of a low pressure, air atomized oil burner for home heating applications. Currently all oil burners on the market are of the pressure atomized, retention head type. These burners have a lower firing rate limit of about 0.5 gallons per hour of oil, due to reliability problems related to small flow passage sizes. High pressure air atomized burners have been shown to be one route to avoid this problem but air compressor cost and reliability have practically eliminated this approach. With the low pressure air atomized burner the air required for atomization can be provided by a fan at 5--8 inches of water pressure. A burner using this concept, termed the Fan-Atomized Burner or FAB has been developed and is currently being commercialized. In the head of the FAB, the combustion air is divided into three parts, much like a conventional retention head burner. This report describes development work on a new concept in which 100% of the air from the fan goes through the atomizer. The primary advantage of this approach is a great simplification of the head design. A nozzle specifically sized for this concept was built and is described in the report. Basic flow pressure tests, cold air velocity profiles, and atomization performance have been measured. A burner head/flame tube has been developed which promotes a torroidal recirculation zone near the nozzle for flame stability. The burner head has been tested in several furnace and boiler applications over the tiring rate range 0.2 to 0.28 gallons per hour. In all cases the burner can operate with very low excess air levels (under 10%) without producing smoke. Flue gas NO{sub x} concentration varied from 42 to 62 ppm at 3% 0{sub 2}. The concept is seen as having significant potential and planned development efforts are discussed.

  5. Quantization of Differences Between Atomic and Nuclear Rest Masses and Selforganization of Atoms and Nuclei

    E-Print Network [OSTI]

    F. A. Gareev; I. E. Zhidkova

    2006-11-15T23:59:59.000Z

    We come to the conclusion that all atomic models based on either the Newton equation and the Kepler laws, or the Maxwell equations, or the Schrodinger and Dirac equations are in reasonable agreement with experimental data. We can only suspect that these equations are grounded on the same fundamental principle(s) which is (are) not known or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in the whole system - nuclei+atoms+condensed matter - nuclear reactions in plasma - can occur at smaller threshold energies than the corresponding ones on free constituents. We were able to quantize phenomenologically the first time the differences between atomic and nuclear rest masses by the formula (in MeV/$c^{2}$) $\\Delta M=\\frac{n_{1}}{n_{2}}*0.0076294, n_{i}=1,2,3,...$ Note that this quantization rule is justified for atoms and nuclei with different $A, N$ and $Z$ and the nuclei and atoms represent a coherent synchronized systems - a complex of coupled oscillators (resonators). The cooperative resonance synchronization mechanisms are responsible for explanation of how the electron volt world can influence the nuclear mega electron volt world. It means that we created new possibilities for inducing and controlling nuclear reactions by atomic processes.

  6. atomic beam studies: Topics by E-print Network

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

    ment when the atom is in a magnetic field of flux density B is BU &ff gp. If B & 0. 1 Tesla, then p, ff pii for atomic hydrogen, where p is the Bohr magneton (pg efi2m). For...

  7. atomic weight values: Topics by E-print Network

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

    a sample of 10 100 atoms. Sumei Huang; Girish S. Agarwal 2015-01-10 3 Power laws and fractal behavior in nuclear stability, atomic weights and molecular weights Physics Websites...

  8. atomic energy levels: Topics by E-print Network

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

    atomic energy levels A. Yilmaz; G. Hacibekiroglu; E. Bolcal; Y. Polatoglu 2008-04-01 2 Energy Levels of "Hydrogen Atom" in Discrete Time Dynamics Quantum Physics (arXiv)...

  9. CHEMICAL REDUCTION OF REFRACTORY OXIDES BY ATOMIC HYDROGEN

    E-Print Network [OSTI]

    Dooley, D.

    2011-01-01T23:59:59.000Z

    by thermal energy atanic hydrogen has been investigated by00 2 is reduced by atomic hydrogen compared with A1 0 2 3 isof redudng AlP3 by atomic hydrogen can he ohtained from the

  10. atomic parameter model: Topics by E-print Network

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

    1913 Bohr model of the hydrogen atom was replaced by Schrdingers wave mechanical model in 1926. In his planetary model of the hydrogen atom (see figure below) Bohr began...

  11. atomic models: Topics by E-print Network

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

    1913 Bohr model of the hydrogen atom was replaced by Schrdingers wave mechanical model in 1926. In his planetary model of the hydrogen atom (see figure below) Bohr began...

  12. 8.422 Atomic and Optical Physics II, Spring 2005

    E-Print Network [OSTI]

    Chuang, Isaac

    This is the second of a two-semester subject sequence beginning with Atomic and Optical Physics I (8.421) that provides the foundations for contemporary research in selected areas of atomic and optical physics. Topics ...

  13. atom transfer reactions: Topics by E-print Network

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

    2d-PIC simulation of atomic clusters in intense laser fields F. Greschik and H.-J. Kull, Plasma Physics and Fusion Websites Summary: properties of atomic clusters (Ditmire et al....

  14. atomic bomb related: Topics by E-print Network

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

    G. Silva; W. T. Cruz; C. A. S. Almeida 2014-07-17 42 Instead of splitting the atom --the Plasma Physics and Fusion Websites Summary: the atomic bomb and led to civilian nuclear...

  15. United States Atomic Energy Commission formed, part 2

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

    formed, part 2 As we continue looking at the transition of thinking that led to the United States Atomic Energy Commission and away from a United Nations Atomic Energy Commission,...

  16. Squeezing collective atomic spins with an optical resonator

    E-Print Network [OSTI]

    Leroux, Ian Daniel

    2011-01-01T23:59:59.000Z

    This thesis describes two methods of overcoming the standard quantum limit of signal-to-noise ratio in atomic precision measurements. In both methods, the interaction between an ultracold atomic ensemble and an optical ...

  17. Direct Evidence of Lithium-Induced Atomic Ordering in Amorphous...

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

    Evidence of Lithium-Induced Atomic Ordering in Amorphous TiO2 Nanotubes . Direct Evidence of Lithium-Induced Atomic Ordering in Amorphous TiO2 Nanotubes . Abstract: In this paper,...

  18. Hybrid approaches to quantum information using ions, atoms and photons

    E-Print Network [OSTI]

    Cetina, Marko, Ph. D. Massachusetts Institute of Technology

    2011-01-01T23:59:59.000Z

    This thesis presents two hybrid systems for quantum information processing - one joining cold ions and cold atoms and another coupling linear chains of atomic ions with photons via an optical resonator. The first experimental ...

  19. Ris Report No. 327 Danish Atomic Energy Commission

    E-Print Network [OSTI]

    Risø Report No. 327 Danish Atomic Energy Commission Research Establishment Risø Metallurgy Atomic Energy Commission Research Establishment Risø METALLURGY DEPARTMENT PROGRESS REPORT for the Period Commission Research Establishment Risø METALLURGY DEPARTMENT PROGRESS REPORT for the Period 1 January to 31

  20. Design and analysis of a monolithic flexure atomic force microscope

    E-Print Network [OSTI]

    Ljubicic, Dean M

    2008-01-01T23:59:59.000Z

    This thesis details the design, manufacture, and testing of a sub-nanometer accuracy atomic force microscope. It was made to be integrated into the Sub-Atomic Measuring Machine (SAMM) in collaboration with the University ...

  1. atomic collision experiments: Topics by E-print Network

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

    theoretical analysis of atomic four-wave mixing via a collision of two Bose-Einstein condensates of metastable helium atoms, and compare the results to a recent experiment. We...

  2. atom chip fabrication: Topics by E-print Network

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

    21 Combined chips for atom optics A. Gnther,1, Physics Websites Summary: -Einstein condensates on a combined atom chip. The combined structure consists of a large-scale "carrier...

  3. atom molecular mechanics: Topics by E-print Network

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

    planetary model of the hydrogen atom (see figure below) Bohr began with a Newtonian analysis Rioux, Frank 10 Atomic and Molecular Quantum Theory Course Number: C561 1 Now, Why do...

  4. atoms li na: Topics by E-print Network

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

    ground (doublet) atomic 2S(L 0)-state. It is straightforward to generalize our analysis to other bound states of the three-electron Li atom. Alexei M. Frolov; David M....

  5. Capture Dynamics of Ultracold Atoms in the Presence of an Impurity Ion

    E-Print Network [OSTI]

    J. M. Schurer; A. Negretti; P. Schmelcher

    2015-05-01T23:59:59.000Z

    Following the sudden creation of a single ion in a quasi one-dimensional trapped ultracold ensemble of bosonic atoms, the major part of the atoms is captured in the vicinity of the ion, while the remaining fraction is emitted towards the outer regions of the trap. Subsequently, the two energy scales stemming from the trapping potential and the atom-ion interaction give rise to two major density oscillations. While the first one corresponds to a dipole oscillation, the second one results from a coherent superposition of an atom-ion bound and a trap state which causes spatial coherence and population transfer between the two density fractions. Induced by the dynamical build-up of correlations, this second oscillation exhibits a collapse and revival behavior. We apply the ab initio multiconfiguration time-dependent Hartree method for bosons to explore the nonequilibrium quantum dynamics and analyze it via a cluster expansion approach. The latter is adapted to bosonic systems of fixed particle number which provides us with a thorough understanding of the complicated many-body processes.

  6. atomic nano-generators actinium-225-labeled: Topics by E-print...

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

    with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory...

  7. atomic energy program: Topics by E-print Network

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

    atomic energy program First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Atomizer: A Dynamic Atomicity...

  8. Method of performing MRI with an atomic magnetometer

    DOE Patents [OSTI]

    Savukov, Igor Mykhaylovich; Matlashov, Andrei Nikolaevich; Espy, Michelle A; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry; Zotev, Vadim Sergeyevich

    2013-08-27T23:59:59.000Z

    A method and apparatus are provided for performing an in-situ magnetic resonance imaging of an object. The method includes the steps of providing an atomic magnetometer, coupling a magnetic field generated by magnetically resonating samples of the object through a flux transformer to the atomic magnetometer and measuring a magnetic resonance of the atomic magnetometer.

  9. Method of performing MRI with an atomic magnetometer

    DOE Patents [OSTI]

    Savukov, Igor Mykhaylovich; Matlashov, Andrei Nikolaevich; Espy, Michelle A.; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry; Zotev, Vadim Sergeyevich

    2012-11-06T23:59:59.000Z

    A method and apparatus are provided for performing an in-situ magnetic resonance imaging of an object. The method includes the steps of providing an atomic magnetometer, coupling a magnetic field generated by magnetically resonating samples of the object through a flux transformer to the atomic magnetometer and measuring a magnetic resonance of the atomic magnetometer.

  10. Relativistic and QED corrections for the Beryllium atom Krzysztof Pachucki

    E-Print Network [OSTI]

    Pachucki, Krzysztof

    Relativistic and QED corrections for the Beryllium atom Krzysztof Pachucki #3; Institute are calculated for the ground state of the beryllium atom and its positive ion. A basis set of correlated of high precision theoretical predictions for energy levels of the beryllium atom and light ions. Our

  11. Optical Spectroscopy of Hydrogenic Atoms MIT Department of Physics

    E-Print Network [OSTI]

    Seager, Sara

    Optical Spectroscopy of Hydrogenic Atoms MIT Department of Physics (Dated: September 1, 2013) This experiment is an exercise in optical spectroscopy in a study of the spectra of "hydrogenic" atoms, i.e. atoms with one "optical" electron outside a closed shell of other electrons. Measurements include finding

  12. Classical Helium Atom with Radiation Reaction G. Camelio,1

    E-Print Network [OSTI]

    Carati, Andrea

    Classical Helium Atom with Radiation Reaction G. Camelio,1 A. Carati,2 and L. Galgani2 1) Universit November 2011) We study a classical model of Helium atom in which, in addition to the Coulomb forces be singular with respect to that of Lebesgue. PACS numbers: 05.45.-a, 41.60.-m Keywords: classical Helium atom

  13. Critical Nuclear Charges for N-Electron Atoms

    E-Print Network [OSTI]

    Kais, Sabre

    Critical Nuclear Charges for N-Electron Atoms ALEXEI V. SERGEEV, SABRE KAIS Department of Chemistry, which is treated as a continuous parameter, approaches its critical value. The critical nuclear charge: critical nuclear charges; N-electron atoms; stability of atomic dianions Introduction he question

  14. Determination of Atomic Data Pertinent to the Fusion Energy Program

    SciTech Connect (OSTI)

    Reader, J.

    2013-06-11T23:59:59.000Z

    We summarize progress that has been made on the determination of atomic data pertinent to the fusion energy program. Work is reported on the identification of spectral lines of impurity ions, spectroscopic data assessment and compilations, expansion and upgrade of the NIST atomic databases, collision and spectroscopy experiments with highly charged ions on EBIT, and atomic structure calculations and modeling of plasma spectra.

  15. Friction forces on atoms after acceleration

    E-Print Network [OSTI]

    Francesco Intravaia; Vanik E. Mkrtchian; Stefan Buhmann; Stefan Scheel; Diego A. R. Dalvit; Carsten Henkel

    2015-02-04T23:59:59.000Z

    The aim of this paper is to revisit the calculation of atom-surface quantum friction in the quantum field theory formulation put forward by Barton [New J. Phys. 12 (2010) 113045]. We show that the power dissipated into field excitations and the associated friction force depend on how the atom is boosted from being initially at rest to a configuration in which it is moving at constant velocity (v) parallel to the planar interface. In addition, we point out that there is a subtle cancellation between the one-photon and part of the two-photon dissipating power, resulting in a leading order contribution to the frictional power which goes as v^4. These results are also confirmed by an alternative calculation of the average radiation force, which scales as v^3.

  16. Hydrogen atom in Palatini theories of gravity

    E-Print Network [OSTI]

    Gonzalo J. Olmo

    2008-06-03T23:59:59.000Z

    We study the effects that the gravitational interaction of $f(R)$ theories of gravity in Palatini formalism has on the stationary states of the Hydrogen atom. We show that the role of gravity in this system is very important for lagrangians $f(R)$ with terms that grow at low curvatures, which have been proposed to explain the accelerated expansion rate of the universe. We find that new gravitationally induced terms in the atomic Hamiltonian generate a strong backreaction that is incompatible with the very existence of bound states. In fact, in the 1/R model, Hydrogen disintegrates in less than two hours. The universe that we observe is, therefore, incompatible with that kind of gravitational interaction. Lagrangians with high curvature corrections do not lead to such instabilities.

  17. Chiral meta-atoms rotated by light

    SciTech Connect (OSTI)

    Liu Mingkai; Powell, David A.; Shadrivov, Ilya V. [Nonlinear Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia)

    2012-07-16T23:59:59.000Z

    We study the opto-mechanical properties of coupled chiral meta-atoms based on a pair of twisted split-ring resonators. By using a simple analytical model in conjunction with the Maxwell stress tensor, we capture insight into the mechanism and find that this structure can be used as a general prototype of subwavelength light-driven actuators over a wide range of frequencies. This coupled structure can provide a strong and tunable torque, and can support different opto-mechanical modes, including uniform rotation, periodically variable rotation and damped oscillations. Our results suggest that chiral meta-atoms are good candidates for creating sub-wavelength motors or wrenches controlled by light.

  18. Liquid crystal variable retarders in atomic scattering

    SciTech Connect (OSTI)

    Furst, J.E.; Yu, D.H.; Hayes, P.A.; DSouza, C.M.; Williams, J.F. [Physics Department, Centre for Atomic, Molecular, and Surface Physics, The University of Western Australia, Nedlands. WA. 6907 (Australia)] [Physics Department, Centre for Atomic, Molecular, and Surface Physics, The University of Western Australia, Nedlands. WA. 6907 (Australia)

    1996-11-01T23:59:59.000Z

    The applications of liquid crystal variable retarders in the production of spin-polarized electrons and in the determination of the polarization of optical radiation from atoms excited by polarized electrons are discussed. The advantages of using liquid crystal variable retarders in the measurement of Stokes parameters are insensitivity to the incident photon direction, large transmission diameter, variable retardation over large wavelength range without mechanical movement, and {ital in} {ital situ} calibration. {copyright} {ital 1996 American Institute of Physics.}

  19. Axion Dark Matter Detection using Atomic Transitions

    E-Print Network [OSTI]

    P. Sikivie

    2014-09-09T23:59:59.000Z

    Dark matter axions may cause transitions between atomic states that differ in energy by an amount equal to the axion mass. Such energy differences are conveniently tuned using the Zeeman effect. It is proposed to search for dark matter axions by cooling a kilogram-sized sample to milliKelvin temperatures and count axion induced transitions using laser techniques. This appears an appropriate approach to axion dark matter detection in the $10^{-4}$ eV mass range.

  20. Loading and characterization of a printed-circuit-board atomic ion trap Kenneth R. Brown, Robert J. Clark, Jaroslaw Labaziewicz, Philip Richerme, David R. Leibrandt, and Isaac L. Chuang

    E-Print Network [OSTI]

    Richerme, Phil

    -dimensional 3D lay- ered planar traps 6­8 and the ability to integrate control electronics below the electrode of new trap geometries and ion shuttling techniques. In this Brief Report, we demonstrate the loading

  1. Atomic Inference from Weak Gravitational Lensing Data

    SciTech Connect (OSTI)

    Marshall, Phil; /KIPAC, Menlo Park

    2005-12-14T23:59:59.000Z

    We present a novel approach to reconstructing the projected mass distribution from the sparse and noisy weak gravitational lensing shear data. The reconstructions are regularized via the knowledge gained from numerical simulations of clusters, with trial mass distributions constructed from n NFW profile ellipsoidal components. The parameters of these ''atoms'' are distributed a priori as in the simulated clusters. Sampling the mass distributions from the atom parameter probability density function allows estimates of the properties of the mass distribution to be generated, with error bars. The appropriate number of atoms is inferred from the data itself via the Bayesian evidence, and is typically found to be small, reecting the quality of the data. Ensemble average mass maps are found to be robust to the details of the noise realization, and succeed in recovering the demonstration input mass distribution (from a realistic simulated cluster) over a wide range of scales. As an application of such a reliable mapping algorithm, we comment on the residuals of the reconstruction and the implications for predicting convergence and shear at specific points on the sky.

  2. Classical Helium Atom with Radiation Reaction

    E-Print Network [OSTI]

    G. Camelio; A. Carati; L. Galgani

    2011-11-24T23:59:59.000Z

    We study a classical model of Helium atom in which, in addition to the Coulomb forces, the radiation reaction forces are taken into account. This modification brings in the model a new qualitative feature of a global character. Indeed, as pointed out by Dirac, in any model of classical electrodynamics of point particles involving radiation reaction one has to eliminate, from the a priori conceivable solutions of the problem, those corresponding to the emission of an infinite amount of energy. We show that the Dirac prescription solves a problem of inconsistency plaguing all available models which neglect radiation reaction, namely, the fact that in all such models most initial data lead to a spontaneous breakdown of the atom. A further modification is that the system thus acquires a peculiar form of dissipation. In particular, this makes attractive an invariant manifold of special physical interest, the zero--dipole manifold, that corresponds to motions in which no energy is radiated away (in the dipole approximation). We finally study numerically the invariant measure naturally induced by the time--evolution on such a manifold, and this corresponds to studying the formation process of the atom. Indications are given that such a measure may be singular with respect to that of Lebesgue.

  3. Generating Entanglement between Atomic Spins with Low-Noise Probing of an Optical Cavity

    E-Print Network [OSTI]

    Cox, Kevin C; Greve, Graham P; Thompson, James K

    2015-01-01T23:59:59.000Z

    Atomic projection noise limits the ultimate precision of all atomic sensors, including clocks, inertial sensors, magnetometers, etc. The independent quantum collapse of $N$ atoms into a definite state (for example spin up or down) leads to an uncertainty $\\Delta \\theta_{SQL}=1/\\sqrt{N}$ in the estimate of the quantum phase accumulated during a Ramsey sequence or its many generalizations. This phase uncertainty is referred to as the standard quantum limit. Creating quantum entanglement between the $N$ atoms can allow the atoms to partially cancel each other's quantum noise, leading to reduced noise in the phase estimate below the standard quantum limit. Recent experiments have demonstrated up to $10$~dB of phase noise reduction relative to the SQL by making collective spin measurements. This is achieved by trapping laser-cooled Rb atoms in an optical cavity and precisely measuring the shift of the cavity resonance frequency by an amount that depends on the number of atoms in spin up. Detecting the probe light ...

  4. Generating Entanglement between Atomic Spins with Low-Noise Probing of an Optical Cavity

    E-Print Network [OSTI]

    Kevin C. Cox; Joshua M. Weiner; Graham P. Greve; James K. Thompson

    2015-04-20T23:59:59.000Z

    Atomic projection noise limits the ultimate precision of all atomic sensors, including clocks, inertial sensors, magnetometers, etc. The independent quantum collapse of $N$ atoms into a definite state (for example spin up or down) leads to an uncertainty $\\Delta \\theta_{SQL}=1/\\sqrt{N}$ in the estimate of the quantum phase accumulated during a Ramsey sequence or its many generalizations. This phase uncertainty is referred to as the standard quantum limit. Creating quantum entanglement between the $N$ atoms can allow the atoms to partially cancel each other's quantum noise, leading to reduced noise in the phase estimate below the standard quantum limit. Recent experiments have demonstrated up to $10$~dB of phase noise reduction relative to the SQL by making collective spin measurements. This is achieved by trapping laser-cooled Rb atoms in an optical cavity and precisely measuring the shift of the cavity resonance frequency by an amount that depends on the number of atoms in spin up. Detecting the probe light with high total efficiency reduces excess classical and quantum back-action of the probe. Here we discuss recent progress and a technique for reducing the relative frequency noise between the probe light and the optical cavity, a key requirement for further advances.

  5. Radiative friction on an excited atom moving in vacuum

    E-Print Network [OSTI]

    Wei Guo

    2012-04-30T23:59:59.000Z

    It is known that, when an excited atom spontaneously emits one photon, two effects are produced. First, the atom's internal and external states are entangled with the states of the emitted photon. Second, the atom receives a momentum transfered from the photon. In this work, the dynamics of such an atom in vacuum is studied. Through a specific calculation, it is demonstrated that these effects cause the atom to experience, on average, a friction force opposite to its initial velocity. Properties of the force are also discussed.

  6. Atomic Structure of Benzene Which Accounts for Resonance Energy

    E-Print Network [OSTI]

    Raji Heyrovska

    2008-07-09T23:59:59.000Z

    Benzene is a hexagonal molecule of six carbon atoms, each of which is bound to six hydrogen atoms. The equality of all six CC bond lengths, despite the alternating double and single bonds, and the surplus (resonance) energy, led to the suggestion of two resonanting structures. Here, the new atomic structure shows that the bond length equality is due to three carbon atoms with double bond radii bound to three other carbon atoms with resonance bond radii (as in graphene). Consequently, there are two kinds of CH bonds of slightly different lengths. The bond energies account for the resonance energy.

  7. Novel rubidium atomic beam with an alkali dispenser source

    SciTech Connect (OSTI)

    Roach, Timothy M.; Henclewood, Dwayne [College of the Holy Cross, Worcester, Massachusetts 01610 (United States)

    2004-11-01T23:59:59.000Z

    We describe a novel atomic beam apparatus with a resistively heated alkali dispenser source and a cold-pumped intermediate chamber. Using laser fluorescence spectroscopy we have measured the atomic density to be 3x10{sup 11} atoms/m{sup 3} and the total flux to be 5x10{sup 8} atoms/s in a 0.3 cm diameter beam. We have also characterized the velocity distribution of the source based on the Doppler-shifted fluorescence spectrum. The compact geometry, flexibility, and simplicity of the beam may make it useful as an optical frequency reference or for experiments on atom-cooling.

  8. Atomizing apparatus for making polymer and metal powders and whiskers

    DOE Patents [OSTI]

    Otaigbe, Joshua U. (Ames, IA); McAvoy, Jon M. (Moline, IL); Anderson, Iver E. (Ames, IA); Ting, Jason (Ames, IA); Mi, Jia (Pittsburgh, PA); Terpstra, Robert (Ames, IA)

    2003-03-18T23:59:59.000Z

    Method for making polymer particulates, such as spherical powder and whiskers, by melting a polymer material under conditions to avoid thermal degradation of the polymer material, atomizing the melt using gas jet means in a manner to form atomized droplets, and cooling the droplets to form polymer particulates, which are collected for further processing. Atomization parameters can be controlled to produce polymer particulates with controlled particle shape, particle size, and particle size distribution. For example, atomization parameters can be controlled to produce spherical polymer powders, polymer whiskers, and combinations of spherical powders and whiskers. Atomizing apparatus also is provided for atoomizing polymer and metallic materials.

  9. Roles of additives and surface control in slurry atomization

    SciTech Connect (OSTI)

    Tsai, S.C.

    1990-07-10T23:59:59.000Z

    Airblast atomization of micronized coal water slurry is carried out using twin-fluid jet atomizers of various distributor designs. Drop size and size distribution are measured using the laser diffraction technique. We found that the atomized drop sizes of micronized coal water slurries substantially decrease as the atomizing air pressure exceeds a threshold value. We also found that the atomized drop size, represented by the mass median diameter (MMD) can be described by the wave mechanism-based models in terms of three non-dimensional groups, namely, slurry-to-air mass ratio, the Weber number, and the Ohnesorge number. 11 refs.

  10. Study atom-vacuum interaction by the weak measurement technique

    E-Print Network [OSTI]

    M. Zhang; S. Y. Zhu

    2014-10-27T23:59:59.000Z

    Quantum weak measurement attracts much interests recently [Rev. Mod. Phys. 86, 307 (2014)], as it could amplify some weak signals and provide a technique to observe the nonclassical phenomenons. Here, we apply this technique to study the interaction between the free atoms and the vacuum in a cavity. Due to the gradient field in the vacuum cavity, the external orbital motions and the internal electronic states of the atoms can be weakly coupled via the atom-field electric-dipole interaction. We show an interesting phenomenon that, within the properly post-selected internal states, the weak atom-vacuum interaction could generate a large change to the external motions of atoms.

  11. Quantization of Differences Between Atomic and Nuclear Rest Masses and Selforganization of Atoms and Nuclei

    E-Print Network [OSTI]

    Gareev, F A

    2006-01-01T23:59:59.000Z

    We come to conclusion that the all atomic models based either on the Newton equation and the Kepler laws or on the Maxwell equations or on the Schrodinger and Dirac equations achieved reasonable agreement with experimental data. We can only suspect that these equations are grounded on the same fundamental principle(s) which is(are) not known or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in whole system - nuclei+atoms+condensed matter - nuclear reactions in plasma - can occur at smaller threshold energies then corresponding ones on free constituents.We were able to quantize phenomenologically (numerology) the first time the differences between atomic and nuclear rest masses according to the formula (in MeV/$c^{2}$) $\\Delta M=0.0076294*n_{1}*2^{n_{2}}, n_{1}=1,2,3,..., n_{2}=1,\\pm2,\\pm4,\\pm8,... $. Note that this quantization rule is justified for atoms and nuclei with different $A, N$ and $Z$ and the nuclei and atoms represent a coherent synch...

  12. Atoms in Flight: The Remarkable Connections between Atomic and Hadronic Physics

    SciTech Connect (OSTI)

    Brodsky, Stanley J.; /SLAC

    2012-02-16T23:59:59.000Z

    Atomic physics and hadron physics are both based on Yang Mills gauge theory; in fact, quantum electrodynamics can be regarded as the zero-color limit of quantum chromodynamics. I review a number of areas where the techniques of atomic physics provide important insight into the theory of hadrons in QCD. For example, the Dirac-Coulomb equation, which predicts the spectroscopy and structure of hydrogenic atoms, has an analog in hadron physics in the form of light-front relativistic equations of motion which give a remarkable first approximation to the spectroscopy, dynamics, and structure of light hadrons. The renormalization scale for the running coupling, which is unambiguously set in QED, leads to a method for setting the renormalization scale in QCD. The production of atoms in flight provides a method for computing the formation of hadrons at the amplitude level. Conversely, many techniques which have been developed for hadron physics, such as scaling laws, evolution equations, and light-front quantization have equal utility for atomic physics, especially in the relativistic domain. I also present a new perspective for understanding the contributions to the cosmological constant from QED and QCD.

  13. Forecast of Standard Atomic Weights for the Mononuclidic Elements – 2011

    SciTech Connect (OSTI)

    Holden, N.E.; Holden, N.; Holden,N.E.

    2011-07-27T23:59:59.000Z

    In this short report, I will provide an early warning about potential changes to the standard atomic weight values for the twenty mononuclidic and the so-called pseudo-mononuclidic ({sup 232}Th and {sup 231}Pa) chemical elements due to the estimated changes in the mass values to be published in the next Atomic Mass Tables within the next two years. There have been many new measurements of atomic masses, since the last published Atomic Mass Table. The Atomic Mass Data Center has released an unpublished version of the present status of the atomic mass values as a private communication. We can not update the Standard Atomic Weight Table at this time based on these unpublished values but we can anticipate how many changes are probably going to be expected in the next few years on the basis of the forthcoming publication of the Atomic Mass Table. I will briefly discuss the procedures that the Atomic Weights Commission used in deriving the recommended Standard Atomic Weight values and their uncertainties from the atomic mass values. I will also discuss some concern raised about a proposed change in the definition of the mole. The definition of the mole is now connected directly to the mass of a {sup 12}C isotope (which is defined as 12 exactly) and to the kilogram. A change in the definition of the mole will probably impact the mass of {sup 12}C.

  14. Ultracold Heteronuclear Mixture of Ground and Excited State Atoms

    E-Print Network [OSTI]

    Khramov, Alexander; Dowd, William; Roy, Richard; Makrides, Constantinos; Petrov, Alexander; Kotochigova, Svetlana; Gupta, Subhadeep

    2014-01-01T23:59:59.000Z

    We report on the realization of an ultracold mixture of lithium atoms in the ground state and ytterbium atoms in the excited metastable 3P2 state. Such a mixture can support broad magnetic Feshbach resonances which may be utilized for the production of ultracold molecules with an electronic spin degree of freedom, as well as novel Efimov trimers. We investigate the interaction properties of the mixture in the presence of an external magnetic field and find an upper limit for the background interspecies two-body inelastic decay coefficient of K'2 < 3e-12 cm^3/s for the 3P2 m_J=-1 substate. We calculate the dynamic polarizabilities of the Yb 3P2 magnetic substates for a range of wavelengths, and find good agreement with our measurements at 1064nm. Our calculations also allow the identification of magic frequencies where Yb ground and metastable states are identically trapped and the determination of the interspecies van der Waals coefficients.

  15. Final report on LDRD project : narrow-linewidth VCSELs for atomic microsystems.

    SciTech Connect (OSTI)

    Chow, Weng Wah; Geib, Kent Martin; Peake, Gregory Merwin; Serkland, Darwin Keith

    2011-09-01T23:59:59.000Z

    Vertical-cavity surface-emitting lasers (VCSELs) are well suited for emerging photonic microsystems due to their low power consumption, ease of integration with other optical components, and single frequency operation. However, the typical VCSEL linewidth of 100 MHz is approximately ten times wider than the natural linewidth of atoms used in atomic beam clocks and trapped atom research, which degrades or completely destroys performance in those systems. This report documents our efforts to reduce VCSEL linewidths below 10 MHz to meet the needs of advanced sub-Doppler atomic microsystems, such as cold-atom traps. We have investigated two complementary approaches to reduce VCSEL linewidth: (A) increasing the laser-cavity quality factor, and (B) decreasing the linewidth enhancement factor (alpha) of the optical gain medium. We have developed two new VCSEL devices that achieved increased cavity quality factors: (1) all-semiconductor extended-cavity VCSELs, and (2) micro-external-cavity surface-emitting lasers (MECSELs). These new VCSEL devices have demonstrated linewidths below 10 MHz, and linewidths below 1 MHz seem feasible with further optimization.

  16. Properties of Atomic Gas in Spiral Galaxies

    E-Print Network [OSTI]

    Robert Braun

    1998-04-29T23:59:59.000Z

    (Abridged) Although both Warm (WNM, 10^4 K) and Cool (CNM, about 100 K) atomic phases coexist in many environments, the dominant mass contribution within a galaxy's star-forming disk (R_25) is that of the CNM. Mass fractions of 60 to 90% are found within R_25, in the form of moderately opaque filaments with a face-on surface covering factor 15%. The kinetic temperature of the CNM increases systematically with galactocentric radius, from some 50 to 200 K, as expected for a radially declining thermal pressure in the galaxy mid-plane. Galaxies of different Hubble type form a nested distribution in T_K(R), apparently due to the mean differences in pressure which result from the different stellar and gas surface densities. The opaque CNM disappears abruptly near R_25, where the low thermal pressure can no longer support the condensed atomic phase. The CNM is apparently a prerequisite for star formation. Median line profiles of the CNM display an extremely narrow line core (FWHM about 6 km/s) together with broad Lorentzian wings (FWHM about 30 km/s). The line core is consistent with only opacity broadening of a thermal profile. The spatial distribution of CNM linewidths is not random. High linewidths occur in distinct shell-like structures with diameter of 100's of pc to kpc's, which show some correlation with diffuse H-alpha shells. The primary source of ``turbulent'' linewidth in the atomic ISM appears to be organized motions due to localized energy injection on a scale of a few 100 pc.

  17. Sixteenth International Conference on the physics of electronic and atomic collisions

    SciTech Connect (OSTI)

    Dalgarno, A.; Freund, R.S.; Lubell, M.S.; Lucatorto, T.B. (eds.)

    1989-01-01T23:59:59.000Z

    This report contains abstracts of papers on the following topics: photons, electron-atom collisions; electron-molecule collisions; electron-ion collisions; collisions involving exotic species; ion- atom collisions, ion-molecule or atom-molecule collisions; atom-atom collisions; ion-ion collisions; collisions involving rydberg atoms; field assisted collisions; collisions involving clusters and collisions involving condensed matter.

  18. Efficiency optimization for Atomic Frequency Comb storage

    E-Print Network [OSTI]

    M. Bonarota; J. Ruggiero; J. -L. Le Gouët; T. Chanelière

    2009-11-23T23:59:59.000Z

    We study the efficiency of the Atomic Frequency Comb storage protocol. We show that for a given optical depth, the preparation procedure can be optimize to significantly improve the retrieval. Our prediction is well supported by the experimental implementation of the protocol in a \\TMYAG crystal. We observe a net gain in efficiency from 10% to 17% by applying the optimized preparation procedure. In the perspective of high bandwidth storage, we investigate the protocol under different magnetic fields. We analyze the effect of the Zeeman and superhyperfine interaction.

  19. Confinement induced binding of noble gas atoms

    SciTech Connect (OSTI)

    Khatua, Munmun; Pan, Sudip; Chattaraj, Pratim K., E-mail: pkc@chem.iitkgp.ernet.in [Department of Chemistry and Centre for Theoretical Studies, Indian Institute of Technology, Kharagpur 721302 (India)

    2014-04-28T23:59:59.000Z

    The stability of Ng{sub n}@B{sub 12}N{sub 12} and Ng{sub n}@B{sub 16}N{sub 16} systems is assessed through a density functional study and ab initio simulation. Although they are found to be thermodynamically unstable with respect to the dissociation of individual Ng atoms and parent cages, ab initio simulation reveals that except Ne{sub 2}@B{sub 12}N{sub 12} they are kinetically stable to retain their structures intact throughout the simulation time (500 fs) at 298 K. The Ne{sub 2}@B{sub 12}N{sub 12} cage dissociates and the Ne atoms get separated as the simulation proceeds at this temperature but at a lower temperature (77 K) it is also found to be kinetically stable. He-He unit undergoes translation, rotation and vibration inside the cavity of B{sub 12}N{sub 12} and B{sub 16}N{sub 16} cages. Electron density analysis shows that the He-He interaction in He{sub 2}@B{sub 16}N{sub 16} is of closed-shell type whereas for the same in He{sub 2}@B{sub 12}N{sub 12} there may have some degree of covalent character. In few cases, especially for the heavier Ng atoms, the Ng-N/B bonds are also found to have some degree of covalent character. But the Wiberg bond indices show zero bond order in He-He bond and very low bond order in cases of Ng-N/B bonds. The energy decomposition analysis further shows that the ?E{sub orb} term contributes 40.9% and 37.3% towards the total attraction in the He{sub 2} dimers having the same distances as in He{sub 2}@B{sub 12}N{sub 12} and He{sub 2}@B{sub 16}N{sub 16}, respectively. Therefore, confinement causes some type of orbital interaction between two He atoms, which akins to some degree of covalent character.

  20. Quantum Sticking of Atoms on Membranes

    E-Print Network [OSTI]

    Dennis P. Clougherty

    2014-12-05T23:59:59.000Z

    A continuum model for low-energy physisorption on a membrane under tension is proposed and studied with variational mean-field theory. A discontinuous change in the energy-dependent sticking coefficient is predicted under certain conditions. This singularity is a result of the bosonic orthogonality catastrophe of the vibrational states of the membrane. The energy-dependent sticking coefficient is predicted to have exponential scaling in 1/E above the singularity. The application of this model to the quantum sticking of cold hydrogen to suspended graphene is discussed. The model predicts that a beam of atomic hydrogen can be completely reflected by suspended graphene at ultralow energies.

  1. Electric quadrupole transition probabilities for atomic lithium

    SciTech Connect (OSTI)

    Çelik, Gültekin, E-mail: gultekin@selcuk.edu.tr [Department of Physics, Faculty of Science, Selçuk University, Campus 42049 Konya (Turkey); Gökçe, Yasin; Y?ld?z, Murat [Department of Physics, Faculty of Science, Karamanoglu Mehmetbey University, Karaman (Turkey)

    2014-05-15T23:59:59.000Z

    Electric quadrupole transition probabilities for atomic lithium have been calculated using the weakest bound electron potential model theory (WBEPMT). We have employed numerical non-relativistic Hartree–Fock wavefunctions for expectation values of radii and the necessary energy values have been taken from the compilation at NIST. The results obtained with the present method agree very well with the Coulomb approximation results given by Caves (1975). Moreover, electric quadrupole transition probability values not existing in the literature for some highly excited levels have been obtained using the WBEPMT.

  2. Ruthenium / aerogel nanocomposits via Atomic Layer Deposition

    SciTech Connect (OSTI)

    Biener, J; Baumann, T F; Wang, Y; Nelson, E J; Kucheyev, S O; Hamza, A V; Kemell, M; Ritala, M; Leskela, M

    2006-08-28T23:59:59.000Z

    We present a general approach to prepare metal/aerogel nanocomposites via template directed atomic layer deposition (ALD). In particular, we used a Ru ALD process consisting of alternating exposures to bis(cyclopentadienyl)ruthenium (RuCp{sub 2}) and air at 350 C to deposit metallic Ru nanoparticles on the internal surfaces of carbon and silica aerogels. The process does not affect the morphology of the aerogel template and offers excellent control over metal loading by simply adjusting the number of ALD cycles. We also discuss the limitations of our ALD approach, and suggest ways to overcome these.

  3. The solar system mimics a hydrogen atom

    E-Print Network [OSTI]

    Je-An Gu

    2014-03-28T23:59:59.000Z

    The solar system and the hydrogen atom are two well known systems on different scales and look unrelated: The former is a classical system on the scale of about billions of kilometers and the latter a quantum system of about tens of picometers. Here we show a connection between them. Specifically, we find that the orbital radii of the planets mimic the mean radii of the energy levels of a quantum system under the Coulomb-like potential. This connection might be explained by very light dark matter which manifests quantum behavior in the solar system, thereby hinting at a dark matter mass around $8 \\times 10^{-14}$ electron-volts.

  4. Atom-split it for nuclear energy

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumni AlumniFederalAshley BoyleAn overhead viewAtom-split it for

  5. Coherence Induced by Incoherent Pumping Field and Decay Process in Three-level $?$ Type Atomic System

    E-Print Network [OSTI]

    Bao-Quan Ou; Lin-Mei Liang; Cheng-Zu Li

    2007-12-25T23:59:59.000Z

    Following the method of Victor V. Kozlov et al.[PhysRevA. 74. 063829],we inspect the coherence induced by incoherent pump and spontaneous decay process in $\\Lambda$ type three-level atomic system with degenerated lower duplicate levels. The system shows a coherent population trapping state and multi-steady states characteristic in different conditions. Interestingly, two kinds of steady states generated by the system in different sets of pumping and decaying parameters, the "singlet" state and the "triplet" state, exhibit stable or unstable characteristics under the action of pumping field and vacuum reservoir, which promise fruitful applications to atomic coherence and interference in quantum optics.

  6. Natural orbits of atomic Cooper pairs in a nonuniform Fermi gas

    E-Print Network [OSTI]

    Y. H. Pong; C. K. Law

    2006-05-08T23:59:59.000Z

    We examine the basic mode structure of atomic Cooper pairs in an inhomogeneous Fermi gas. Based on the properties of Bogoliubov quasi-particle vacuum, the single particle density matrix and the anomalous density matrix share the same set of eigenfunctions. These eigenfunctions correspond to natural pairing orbits associated with the BCS ground state. We investigate these orbits for a Fermi gas in a spherical harmonic trap, and construct the wave function of a Cooper pair in the form of Schmidt decomposition. The issue of spatial quantum entanglement between constituent atoms in a pair is addressed.

  7. Testing Gravity with Cold-Atom Interferometers

    E-Print Network [OSTI]

    G. W. Biedermann; X. Wu; L. Deslauriers; S. Roy; C. Mahadeswaraswamy; M. A. Kasevich

    2014-12-10T23:59:59.000Z

    We present a horizontal gravity gradiometer atom interferometer for precision gravitational tests. The horizontal configuration is superior for maximizing the inertial signal in the atom interferometer from a nearby proof mass. In our device, we have suppressed spurious noise associated with the horizonal configuration to achieve a differential acceleration sensitivity of 4.2$\\times10^{-9}g/\\sqrt{Hz}$ over a 70 cm baseline or 3.0$\\times10^{-9}g/\\sqrt{Hz}$ inferred per accelerometer. Using the performance of this instrument, we characterize the results of possible future gravitational tests. We complete a proof-of-concept measurement of the gravitational constant with a precision of 3$\\times10^{-4}$ that is competitive with the present limit of 1.2$\\times10^{-4}$ using other techniques. From this measurement, we provide a statistical constraint on a Yukawa-type fifth force at 8$\\times$10$^{-3}$ near the poorly known length scale of 10 cm. Limits approaching 10$^{-5}$ appear feasible. We discuss improvements that can enable uncertainties falling well below 10$^{-5}$ for both experiments.

  8. String model of the Hydrogen Atom

    E-Print Network [OSTI]

    Omar Yepez

    2007-01-31T23:59:59.000Z

    A non-moving electron hydrogen model is proposed, resolving a long standing contradiction (94 years) in the hydrogen atom. This, however, forces to not use the "in an orbit point particle kinetic energy" as the phenomenon responsible for the atom stability. The repulsion between the masses of the electron and proton is what is responsible of such stability. The mass of the electron is a field fully described by the uncertainty principle through the confinement of the particle, which is also consistent with the general theory of relativity that states: "mass-energy tells the space how to bend". Ergo, mass exerts a tension on its surrounding space and the lighter the mass the larger the space it will occupy. Based on this concept it is proposed that the orbital is the electron. The electron's orbitals are just the electron's different ways of intersecting the space; with different magnetic momenta. The coupling of this momenta with the magnetic moment of the proton finally explains the hyperfine structure of the hydrogen spectrum with an overwhelming simplicity

  9. Normal-Mode Spectroscopy of a Single-Bound-AtomCavity System P. Maunz, T. Puppe, I. Schuster, N. Syassen, P. W. H. Pinkse, and G. Rempe

    E-Print Network [OSTI]

    Rempe, Gerhard

    Normal-Mode Spectroscopy of a Single-Bound-Atom­Cavity System P. Maunz, T. Puppe, I. Schuster, N is stored in an intracavity dipole trap and cavity cooling is used to compensate for inevitable heating. Two Experimental research in quantum information science with atoms and ions [1] is based on the ability to control

  10. Controlling interactions between highly-magnetic atoms with Feshbach resonances

    E-Print Network [OSTI]

    Svetlana Kotochigova

    2014-10-14T23:59:59.000Z

    This paper reviews current experimental and theoretical progress in the study of dipolar quantum gases of ground and meta-stable atoms with a large magnetic moment. We emphasize the anisotropic nature of Feshbach resonances due to coupling to fast-rotating resonant molecular states in ultracold s-wave collisions between magnetic atoms in external magnetic fields. The dramatic differences in the distribution of resonances of magnetic $^7$S$_3$ chromium and magnetic lanthanide atoms with a submerged 4f shell and non-zero electron angular momentum is analyzed. We focus on Dysprosium and Erbium as important experimental advances have been recently made to cool and create quantum-degenerate gases for these atoms. Finally, we describe progress in locating resonances in collisions of meta-stable magnetic atoms in electronic P states with ground-state atoms, where an interplay between collisional anisotropies and spin-orbit coupling exists.

  11. “Hard probes” of strongly-interacting atomic gases

    SciTech Connect (OSTI)

    Nishida, Yusuke [Los Alamos National Laboratory

    2012-06-18T23:59:59.000Z

    We investigate properties of an energetic atom propagating through strongly interacting atomic gases. The operator product expansion is used to systematically compute a quasiparticle energy and its scattering rate both in a spin-1/2 Fermi gas and in a spinless Bose gas. Reasonable agreement with recent quantum Monte Carlo simulations even at a relatively small momentum k/kF > 1.5 indicates that our large-momentum expansions are valid in a wide range of momentum. We also study a differential scattering rate when a probe atom is shot into atomic gases. Because the number density and current density of the target atomic gas contribute to the forward scattering only, its contact density (measure of short-range pair correlation) gives the leading contribution to the backward scattering. Therefore, such an experiment can be used to measure the contact density and thus provides a new local probe of strongly interacting atomic gases.

  12. Atomic lines in infrared spectra for ultracool dwarfs

    E-Print Network [OSTI]

    Yu. Lyubchik; H. R. A. Jones; Ya. V. Pavlenko; S. Viti; J. C. Pickering; R. Blackwell-Whitehead

    2003-12-22T23:59:59.000Z

    We provide a set of atomic lines which are suitable for the description of ultracool dwarf spectra from 10000 to 25000 \\AA. This atomic linelist was made using both synthetic spectra calculations and existing atlases of infrared spectra of Arcturus and Sunspot umbra. We present plots, which show the comparison of synthetic spectra and observed Arcturus and Sunspot umbral spectra for all atomic lines likely to be observable in high resolution infrared spectra.

  13. Four-level atom interferometer with trichromatic laser fields

    SciTech Connect (OSTI)

    Honda, Kazuhito; Kobayashi, Yoshiyuki; Morinaga, Atsuo [Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba 278-8510 (Japan)

    2007-02-15T23:59:59.000Z

    A four-level atom interferometer comprised of three excited states and one ground state with trichromatic fields coupled between them is investigated using Zeeman sublevels of {sup 3}P{sub 1} and {sup 1}S{sub 0} states of a calcium atom. A theoretical description of the interaction of four-level atoms with trichromatic laser fields is presented and compared with the experimental results of the interference fringes which are generated by the three excited states.

  14. Qubits entanglement dynamics modified by an effective atomic environment

    E-Print Network [OSTI]

    I. Sainz; A. B. Klimov; Luis Roa

    2005-11-28T23:59:59.000Z

    We study entanglement dynamics of a couple of two-level atoms resonantly interacting with a cavity mode and embedded in a dispersive atomic environment. We show that in the absence of the environment the entanglement reaches its maximum value when only one exitation is involved. Then, we find that the atomic environment modifies that entanglement dynamics and induces a typical collapse-revival structure even for an initial one photon Fock state of the field.

  15. Light transport in cold atoms and thermal decoherence

    E-Print Network [OSTI]

    Guillaume Labeyrie; Dominique Delande; Robin Kaiser; Christian Miniatura

    2006-03-17T23:59:59.000Z

    By using the coherent backscattering interference effect, we investigate experimentally and theoretically how coherent transport of light inside a cold atomic vapour is affected by the residual motion of atomic scatterers. As the temperature of the atomic cloud increases, the interference contrast dramatically decreases emphazising the role of motion-induced decoherence for resonant scatterers even in the sub-Doppler regime of temperature. We derive analytical expressions for the corresponding coherence time.

  16. Hydrogen atom in phase space: The Wigner representation

    E-Print Network [OSTI]

    L. Praxmeyer; J. Mostowski; K. Wodkiewicz

    2005-04-06T23:59:59.000Z

    We have found an effective method of calculating the Wigner function, being a quantum analogue of joint probability distribution of position and momentum, for bound states of nonrelativistic hydrogen atom. The formal similarity between the eigenfunctions of nonrelativistic hydrogen atom in the momentum representation and Klein-Gordon propagators has allowed the calculation of the Wigner function for an arbitrary bound state of the hydrogen atom. These Wigner functions for some low lying states are depicted and discussed.

  17. Part 810-ASSISTANCE TO FOREIGN ATOMIC ENERGY ACTIVITIES Sec.

    National Nuclear Security Administration (NNSA)

    834 only) Colombia Croatia Cyprus Czech Republic Denmark Egypt Estonia Finland France Germany Greece Hungary Indonesia International Atomic Energy Agency Ireland Italy Japan...

  18. New Atomic Force Microscope Spectroscopy Probes Local Elasticity...

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

    Materials Characterization New Atomic Force Microscope Spectroscopy Probes Local Elasticity March 04, 2015 Shown is a contact resonance frequency image after nano-oxidation of a...

  19. Exploiting Universality in Atoms with Large Scattering Lengths

    SciTech Connect (OSTI)

    Braaten, Eric

    2012-05-31T23:59:59.000Z

    The focus of this research project was atoms with scattering lengths that are large compared to the range of their interactions and which therefore exhibit universal behavior at sufficiently low energies. Recent dramatic advances in cooling atoms and in manipulating their scattering lengths have made this phenomenon of practical importance for controlling ultracold atoms and molecules. This research project was aimed at developing a systematically improvable method for calculating few-body observables for atoms with large scattering lengths starting from the universal results as a first approximation. Significant progress towards this goal was made during the five years of the project.

  20. atomic energy review: Topics by E-print Network

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

    clouds, the rescattered light undergoes diffusive propagation, which Guerra, Vasco 27 Energy--level splitting in antiprotonic helium atoms Nuclear Theory (arXiv) Summary: Recent...

  1. atomic masses library: Topics by E-print Network

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

    or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in the whole system - nuclei+atoms+condensed matter - nuclear...

  2. atomic mass difference: Topics by E-print Network

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

    or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in the whole system - nuclei+atoms+condensed matter - nuclear...

  3. atom bombardment mass: Topics by E-print Network

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

    or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in the whole system - nuclei+atoms+condensed matter - nuclear...

  4. atom nuclei isotopes: Topics by E-print Network

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

    or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in the whole system - nuclei+atoms+condensed matter - nuclear...

  5. atomic mass differences: Topics by E-print Network

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

    or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in the whole system - nuclei+atoms+condensed matter - nuclear...

  6. atomic weights table: Topics by E-print Network

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

    stability, atomic weights and molecular weights V. Paar, Bijeniccka 32, 10000 Zagreb, Croatia Accepted 15 January 2002 Abstract A power law is introduced weights. The power law...

  7. atomic power teller: Topics by E-print Network

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

    stability, atomic weights and molecular weights V. Paar, Bijeniccka 32, 10000 Zagreb, Croatia Accepted 15 January 2002 Abstract A power law is introduced weights. The power law...

  8. atomic weights tables: Topics by E-print Network

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

    stability, atomic weights and molecular weights V. Paar, Bijeniccka 32, 10000 Zagreb, Croatia Accepted 15 January 2002 Abstract A power law is introduced weights. The power law...

  9. atomic power laboratory: Topics by E-print Network

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

    stability, atomic weights and molecular weights V. Paar, Bijeniccka 32, 10000 Zagreb, Croatia Accepted 15 January 2002 Abstract A power law is introduced weights. The power law...

  10. Unlocking Life's Mysteries (One Atom at a Time)

    Broader source: Energy.gov [DOE]

    The Linac Coherent Light Source (LSCLS) at SLAC National Accelerator Laboratory will allow us to make "molecular movies" and answer many questions surrounding atoms.

  11. Machine Learning for Quantum Mechanical Properties of Atoms in Molecules

    E-Print Network [OSTI]

    Rupp, Matthias; von Lilienfeld, O Anatole

    2015-01-01T23:59:59.000Z

    We introduce machine learning models of quantum mechanical observables of atoms in molecules. Instant out-of-sample predictions for proton and carbon nuclear chemical shifts, atomic core level excitations, and forces on atoms reach accuracies on par with density functional theory reference. Locality is exploited within non-linear regression via local atom-centered coordinate systems. The approach is validated on a diverse set of 9k small organic molecules. Linear scaling is demonstrated for saturated polymers with up to sub-mesoscale lengths.

  12. atomic reactors nouvelles: Topics by E-print Network

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

    cooperative monitoring capability may be of interest for the International Atomic Energy Agency (IAEA) reactor safeguards program and similar regimes. Bowden, N S;...

  13. Atomic detail brownian dynamics simulations of concentrated protein...

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

    detail brownian dynamics simulations of concentrated protein solutions with a mean field treatment of hydrodynamic Atomic detail brownian dynamics simulations of concentrated...

  14. "Seeing" hydrogen atoms to unveil enzyme catalysis | ornl.gov

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

    "Seeing" hydrogen atoms to unveil enzyme catalysis Image shows nuclear density maps in the active site of DHFR where the catalytic group Asp27 and substrate folate have...

  15. Atomic and Molecular Adsorption on Re(0001). | EMSL

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

    Molecular Adsorption on Re(0001). Atomic and Molecular Adsorption on Re(0001). Abstract: Using periodic, self-consistent density functional theory calculations, the adsorption of...

  16. average atom model: Topics by E-print Network

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

    (chemical potential, average ionic charge, free electron density, bound and continuum wave-functions and occupation numbers) are obtained from the average-atom model. The...

  17. Scattering lengths for collisions of hydrogen and deuterium atoms

    E-Print Network [OSTI]

    Chu, X.; Jamieson, M.J.

    Chu,X. Jamieson,M.J. Dalgarno,A. Journal of Physics B: Atomic, Molecular and Optical Physics, Vol. 36 pp L415-L418

  18. atomic plant gathers: Topics by E-print Network

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

    Service; Marla R. Emery; Clare Ginger; Siri Newman; Michael R. B; Giammusso Abstract 2 Search for plant biomagnetism with a sensitive atomic magnetometer Eric Corsini,1,a) Physics...

  19. atomic spectrometry update: Topics by E-print Network

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

    from nuclear waste materials using inductively coupled plasma-atomic emission spectrometry CERN Preprints Summary: 1.1 This practice is applicable to the determination of low...

  20. President Roosevelt Approves Production of Atomic Bomb | National...

    National Nuclear Security Administration (NNSA)

    Approves Production of Atomic Bomb | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation...

  1. ORNL researchers make first observation of atoms moving inside...

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

    observation of atoms moving inside bulk material Selected frames from a sequence of scanning transmission electron microscope images showing the diffusion pathway of a Ce dopant...

  2. Atomic Collision and Ionization Effects in Oxides. | EMSL

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

    is a challenging area for scientific research. Citation: Zhang Y, IT Bae, and WJ Weber.2008."Atomic Collision and Ionization Effects in Oxides."Nuclear Instruments and...

  3. Difference between radiative transition rates in atoms and antiatoms

    E-Print Network [OSTI]

    Dolgov, A D; Rudenko, A S

    2012-01-01T23:59:59.000Z

    We demonstrate that CP violation results in a difference of the partial decay rates of atoms and antiatoms. The magnitude of this difference is estimated.

  4. Difference between radiative transition rates in atoms and antiatoms

    E-Print Network [OSTI]

    A. D. Dolgov; I. B. Khriplovich; A. S. Rudenko

    2012-08-17T23:59:59.000Z

    We demonstrate that CP violation results in a difference of the partial decay rates of atoms and antiatoms. The magnitude of this difference is estimated.

  5. atom lena imager: Topics by E-print Network

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

    IMAGELENA has reported neutral atom observations that may be interpreted as a "secondary stream" having different characteristics and flowing from a higher ecliptic...

  6. Method of trivalent chromium concentration determination by atomic spectrometry

    DOE Patents [OSTI]

    Reheulishvili, Aleksandre N. (Tbilisi, 0183, GE); Tsibakhashvili, Neli Ya. (Tbilisi, 0101, GE)

    2006-12-12T23:59:59.000Z

    A method is disclosed for determining the concentration of trivalent chromium Cr(III) in a sample. The addition of perchloric acid has been found to increase the atomic chromium spectrometric signal due to Cr(III), while leaving the signal due to hexavalent chromium Cr(VI) unchanged. This enables determination of the Cr(III) concentration without pre-concentration or pre-separation from chromium of other valences. The Cr(III) concentration may be measured using atomic absorption spectrometry, atomic emission spectrometry or atomic fluorescence spectrometry.

  7. Atomic-Level Simulations of Epitaxial Recrystallization andAmorphous...

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

    Simulations of Epitaxial Recrystallization and Amorphous-to-Crystalline Transition in 4H-SiC. Atomic-Level Simulations of Epitaxial Recrystallization and Amorphous-to-Crystalline...

  8. US Energy Secretary Samuel Bodman and Russian Atomic Energy Director...

    Energy Savers [EERE]

    Atomic Energy Director Alexander Rumyantsev discuss progress in achieving the Bratislava Nuclear Security Initiatives in Moscow Tuesday, May 24, 2005. The Bratislava agreement was...

  9. Materials - Imaging atoms for better batteries ... | ornl.gov

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

    in the material's atomic arrangement. These location-dependent changes rely on nickel swapping with lithium, and can raise or lower energy barriers for lithium-ion...

  10. australian atomic energy: Topics by E-print Network

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

    Wood begins his narrative on the pioneering years of solar 9 International Atomic Energy Agency CiteSeer Summary: Global warming is acknowledged as a major crisis facing...

  11. Institute for Atom-efficient Chemical Transformations trifold...

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

    of theoretical insights at the atomic level, providing guidance in the discovery of new catalytic materials. Selectivity of formic acid decomposition to CO 2 as a function of...

  12. Single-cell atomic quantum memory for light

    E-Print Network [OSTI]

    Tomas Opatrny

    2006-09-29T23:59:59.000Z

    Recent experiments demonstrating atomic quantum memory for light [B. Julsgaard et al., Nature 432, 482 (2004)] involve two macroscopic samples of atoms, each with opposite spin polarization. It is shown here that a single atomic cell is enough for the memory function if the atoms are optically pumped with suitable linearly polarized light, and quadratic Zeeman shift and/or ac Stark shift are used to manipulate rotations of the quadratures. This should enhance the performance of our quantum memory devices since less resources are needed and losses of light in crossing different media boundaries are avoided.

  13. atomic system based: Topics by E-print Network

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

    complete, up-to-date, user friendly and online atomic Database Management System (DBMS) namely called AIMS by using SQLite (http:www.sqlite.orgabout.html)(8)....

  14. PPPL and General Atomics scientists make breakthrough in understanding...

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

    The left image models the response that suppressed the ELMs while the right image shows a response that was ineffective. Simulation by General Atomics. Researchers from General...

  15. Atomic Absorption Spectrometry Perkin Elmer 500, Chemistry & Biochemistry

    E-Print Network [OSTI]

    Gruner, Daniel S.

    Atomic Absorption Spectrometry · Perkin Elmer 500, Chemistry & Biochemistry · Perkin Elmer 560 AA Harvester-Luminometer scintillation counter, CBMG Centrifuges · Beckman Coulter Optima XL-I Analytical

  16. atomic energy authority: Topics by E-print Network

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

    2013 UNITED KINGDOM ATOMIC ENERGY AUTHORITY The following article appeared in Journal of Nuclear Materials, Volume 442, Issues 1-3, Plasma Physics and Fusion Websites Summary: or...

  17. Atomic structure of nitrate-binding protein crucial for photosynthetic...

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

    structure of nitrate-binding protein crucial for photosynthetic productivity. Atomic structure of nitrate-binding protein crucial for photosynthetic productivity. Abstract:...

  18. atomic binding energy: Topics by E-print Network

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

    Calvin W. Johnson; Joshua T. Staker 2012-08-30 2 Estimating ProteinLigand Binding Free Energy: Atomic Solvation Parameters for Partition Coefficient and Biotechnology...

  19. atomic orbitals calculation: Topics by E-print Network

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

    orbital discretization. We give analytic expressions for evaluating charge density, total energy, Helmholtz free energy and atomic forces without using the eigenvalues and...

  20. atomic structure calculations: Topics by E-print Network

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

    orbital discretization. We give analytic expressions for evaluating charge density, total energy, Helmholtz free energy and atomic forces without using the eigenvalues and...

  1. atomic beam magnetic: Topics by E-print Network

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

    of atomic phase space density. A magnetic offset field is applied to prevent optical pumping to untrapped states. Our results demonstrate that by a suitable choice of the...

  2. alkali atom vapor: Topics by E-print Network

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

    low power requirements, these "chip-scale" atomic Popovic, Zoya 3 Hybrid Optical Pumping of Optically Dense Alkali-Metal Vapor without Quenching Gas M. V. Romalis Physics...

  3. Excitation of two atoms by a propagating single photon pulse

    E-Print Network [OSTI]

    Navneeth Ramakrishnan; Yimin Wang; Valerio Scarani

    2014-11-13T23:59:59.000Z

    We describe the interaction of two two-level atoms in free space with propagating modes of the quantized electromagnetic field, using the time-dependent Heisenberg-Langevin method. For single- photon pulses, we consider the effect of the pulse's spatial and temporal profiles on the atomic excitation. In particular, we find the ideal shape for a pulse to put exactly one excitation in any desired state of the bi-atomic system. Furthermore, we analyze the differences in the atomic dynamics between the cases of Fock state pulses and coherent state pulses.

  4. The Manhattan Project: Making the Atomic Bomb. 1999 edition.

    SciTech Connect (OSTI)

    Gosling, F.G.

    1999-01-01T23:59:59.000Z

    ``The Manhattan Project: Making the Atomic Bomb`` is a short history of the origins and development of the American atomic bomb program during World War II. Beginning with the scientific developments of the pre-war years, the monograph details the role of the United States government in conducting a secret, nationwide enterprise that took science from the laboratory and into combat with an entirely new type of weapon. The monograph concludes with a discussion of the immediate postwar period, the debate over the Atomic Energy Act of 1946, and the founding of the Atomic Energy Commission.

  5. atom probe study: Topics by E-print Network

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

    using both APT and correlative microscopy techniques, a more complete understanding... Bennett, Samantha 2011-02-08 2 ATOM-PROBE TOMOGRAPHIC STUDY OF THE THREE-DIMENSIONAL...

  6. atomized oil burner: Topics by E-print Network

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

    in boilers 17 FINGERPRINTING INORGANIC ARSENIC AND ORGANOARSENIC COMPOUNDS IN IN SITU OIL SHALE RETORT AND PROCESS VOTERS USING A LIQUID CHROMATOGRAPH COUPLED WITH AN ATOMIC...

  7. atomic gold junction: Topics by E-print Network

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

    atoms with opposite persistent currents. This system is closely analogous to the superconducting flux qubit. Single qubit quantum logic gates are performed by modulating the...

  8. Exotic superconducting phases of ultracold atom mixtures on triangular lattices

    E-Print Network [OSTI]

    Mathey, Ludwig; Tsai, Shan-Wen; Castro Neto, Antonio H.

    2007-01-01T23:59:59.000Z

    Exotic Superconducting Phases of Ultracold Atom Mixtures onlattice contain exotic superconducting phases. For spin-1/2competition between superconducting phases with di?erent

  9. atomized uranium silicide: Topics by E-print Network

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

    conditions on the atomic nucleus surface are discussed as well. R. Tsekov 2014-06-18 38 Depleted Uranium Technical Brief Environmental Sciences and Ecology Websites Summary: and...

  10. Isotropically sensitive optical filter employing atomic resonance transitions

    DOE Patents [OSTI]

    Marling, John B. (Livermore, CA)

    1981-01-01T23:59:59.000Z

    An ultra-high Q isotropically sensitive optical filter or optical detector employing atomic resonance transitions. More specifically, atomic resonance transitions utilized in conjunction with two optical bandpass filters provide an optical detector having a wide field of view (.about.2.pi. steradians) and very narrow acceptance bandwidth approaching 0.01 A. A light signal to be detected is transmitted through an outer bandpass filter into a resonantly absorbing atomic vapor, the excited atomic vapor then providing a fluorescence signal at a different wavelength which is transmitted through an inner bandpass filter. The outer and inner bandpass filters have no common transmission band, thereby resulting in complete blockage of all optical signals that are not resonantly shifted in wavelength by the intervening atomic vapor. Two embodiments are disclosed, one in which the light signal raises atoms contained in the atomic vapor from the ground state to an excited state from which fluorescence occurs, and the other in which a pump laser is used to raise the atoms in the ground state to a first excited state from which the light signal then is resonantly absorbed, thereby raising the atoms to a second excited state from which fluorescence occurs. A specific application is described in which an optical detector according to the present invention can be used as an underwater detector for light from an optical transmitter which could be located in an orbiting satellite.

  11. atomic products operation: Topics by E-print Network

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

    (arXiv) Summary: We study mesoscopic superpositions of two component Bose-Einstein condensates. Atomic condensates, with long coherence times, are good systems in which to study...

  12. atomic spin squeezing: Topics by E-print Network

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

    including: producing spin squeezed states via particle collisions in Bose-Einstein condensates, mapping photon squeezing onto atomic ensembles, and quantum non-demolition...

  13. atomic clusters rb12: Topics by E-print Network

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

    Tamas Terlaky NUMBER Neumaier, Arnold 3 Formation of atomic tritium clusters and condensates CERN Preprints Summary: We present an extensive study of the static and dynamic...

  14. atomic clusters: Topics by E-print Network

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

    Tamas Terlaky NUMBER Neumaier, Arnold 3 Formation of atomic tritium clusters and condensates CERN Preprints Summary: We present an extensive study of the static and dynamic...

  15. atomic quantum superposition: Topics by E-print Network

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

    (arXiv) Summary: We study mesoscopic superpositions of two component Bose-Einstein condensates. Atomic condensates, with long coherence times, are good systems in which to study...

  16. atomic collisions vienna: Topics by E-print Network

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

    normally be expected. We collided two optically dressed neutral atomic Bose-Einstein condensates with equal, and opposite, momenta and observed that the usual s-wave distribution...

  17. atomic products department: Topics by E-print Network

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

    (arXiv) Summary: We study mesoscopic superpositions of two component Bose-Einstein condensates. Atomic condensates, with long coherence times, are good systems in which to study...

  18. atomic physics condensed: Topics by E-print Network

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

    REVIEW A 84, 053630 (2011) Multiple dark-bright solitons in atomic Bose-Einstein condensates Mathematics Websites Summary: PHYSICAL REVIEW A 84, 053630 (2011) Multiple...

  19. atomic energy community: Topics by E-print Network

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

    to help small communities develop new energy use and production models centered around "green Walter, M.Todd 3 Atomic Energy for Military Purposes Biology and Medicine Websites...

  20. atomic resolution imaging: Topics by E-print Network

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

    annular dark-field STEM Dunin-Borkowski, Rafal E. 6 Crystal structure retrieval by maximum entropy analysis of atomic resolution incoherent images Materials Science Websites...

  1. atomic resolution images: Topics by E-print Network

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

    annular dark-field STEM Dunin-Borkowski, Rafal E. 6 Crystal structure retrieval by maximum entropy analysis of atomic resolution incoherent images Materials Science Websites...

  2. atomic resolution structure: Topics by E-print Network

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

    An axis of 3-fold symmetry runs through Blaber, Michael 8 Crystal structure retrieval by maximum entropy analysis of atomic resolution incoherent images Materials Science Websites...

  3. atomic resolution structural: Topics by E-print Network

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

    An axis of 3-fold symmetry runs through Blaber, Michael 8 Crystal structure retrieval by maximum entropy analysis of atomic resolution incoherent images Materials Science Websites...

  4. atomic resolution structures: Topics by E-print Network

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

    An axis of 3-fold symmetry runs through Blaber, Michael 8 Crystal structure retrieval by maximum entropy analysis of atomic resolution incoherent images Materials Science Websites...

  5. Alkali vapor pressure modulation on the 100 ms scale in a single-cell vacuum system for cold atom experiments

    SciTech Connect (OSTI)

    Dugrain, Vincent; Reichel, Jakob [Laboratoire Kastler Brossel, ENS, UPMC, CNRS, 24 rue Lhomond, 75005 Paris (France); Rosenbusch, Peter [LNE-SYRTE, Observatoire de Paris, CNRS, UPMC, 61 av de l’Observatoire, 75014 Paris (France)

    2014-08-15T23:59:59.000Z

    We describe and characterize a device for alkali vapor pressure modulation on the 100 ms timescale in a single-cell cold atom experiment. Its mechanism is based on optimized heat conduction between a current-modulated alkali dispenser and a heat sink at room temperature. We have studied both the short-term behavior during individual pulses and the long-term pressure evolution in the cell. The device combines fast trap loading and relatively long trap lifetime, enabling high repetition rates in a very simple setup. These features make it particularly suitable for portable atomic sensors.

  6. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1991-05-08T23:59:59.000Z

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using, a metal hydride.

  7. Probing thermoelectric transport with cold atoms

    E-Print Network [OSTI]

    Charles Grenier; Corinna Kollath; Antoine Georges

    2013-11-10T23:59:59.000Z

    We propose experimental protocols to reveal thermoelectric and thermal effects in the transport properties of ultracold fermionic atoms, using the two-terminal setup recently realized at ETH. We show in particular that, for two reservoirs having equal particle numbers but different temperatures initially, the observation of a transient particle number imbalance during equilibration is a direct evidence of thermoelectric (off-diagonal) transport coefficients. This is a time-dependent analogue of the Seebeck effect, and a corresponding analogue of the Peltier effect can be proposed. We reveal that in addition to the thermoelectric coupling of the constriction a thermoelectric coupling also arises due to the finite dilatation coefficient of the reservoirs. We present a theoretical analysis of the protocols, and assess their feasibility by estimating the corresponding temperature and particle number imbalances in realistic current experimental conditions.

  8. Hydrogen atom on curved noncommutative space

    E-Print Network [OSTI]

    V. G. Kupriyanov

    2013-06-05T23:59:59.000Z

    We have calculated the hydrogen atom spectrum on curved noncommutative space defined by the commutation relations $\\left[ \\hat {x}^{i},\\hat{x}^{j}\\right] =i\\theta\\hat{\\omega}^{ij}\\left( \\hat {x}\\right) $, where $\\theta$ is the parameter of noncommutativity. The external antisymmetric field which determines the noncommutativity is chosen as $\\omega^{ij}(x) =\\varepsilon^{ijk}{x}_{k}f\\left( {x_i}x^{i}\\right) $. In this case the rotational symmetry of the system is conserved, preserving the degeneracy of the energy spectrum. The contribution of the noncommutativity appears as a correction to the fine structure. The corresponding nonlocality is calculated: $\\Delta x\\Delta y \\geq \\frac{\\theta^2}{4} |m\\langle f^2\\rangle| $, where $m$ is a magnetic quantum number.

  9. Atomic force microscopy of biochemically tagged DNA

    SciTech Connect (OSTI)

    Ogletree, D.F.; Kolbe, W.; Spengler, S.; Salmeron, M. (Lawrence Berkeley Laboratory, CA (United States)); Hansma, H.G.; Bezanilla, M. (Univ. of California, Santa Barbara (United States)); Sano, T.; Smith, C.S.; Cantor, C.R. (Boston Univ., MA (United States))

    1993-05-01T23:59:59.000Z

    Small fragments of DNA of known length were made with the polymerase chain reaction. These fragments had biotin molecules covalently attached at their ends. They were subsequently labeled with a chimeric protein fusion between streptavidin and two immunoglobulin G-binding domains of staphyloccocal protein A. This tetrameric species was expected to bind up to four DNA molecules via their attached biotin moieties. The DNA-protein complex was deposited on mica and imaged with an atomic force microscope. The images revealed the protein chimera at the expected location at the ends of the strands of DNA as well as the expected dimers, trimers, and tetramers of DNA bound to a single protein. 25 refs., 5 figs.

  10. Atomic Layer Deposition for SRF Cavities

    SciTech Connect (OSTI)

    Norem, J; Pellin, M J; Antoine, C Z; Ciovati, G; Kneisel, P; Reece, C E; Rimmer, R A; Cooley, L; Gurevich, A V; Ha, Y; Proslier, Th

    2009-05-01T23:59:59.000Z

    We have begun using Atomic Layer Deposition (ALD) to synthesize a variety of surface coatings on coupons and cavities as part of an effort to produce rf structures with significantly better performance and yield than those obtained from bulk niobium, The ALD process offers the possibility of conformally coating complex cavity shapes with precise layered structures with tightly constrained morphology and chemical properties. Our program looks both at the metallurgy and superconducting properties of these coatings, and also their performance in working structures. Initial results include: 1) evidence from point contact tunneling showing magnetic oxides can be a significant limitation to high gradient operation, 2) experimental results showing the production sharp niobium/oxide interfaces from a high temperature bake of ALD coated Al2O3 on niobium surfaces, 3) results from ALD coated structures.

  11. Atomic Layer Deposition for SRF Cavities

    SciTech Connect (OSTI)

    Proslier, Th.; Ha, Y.; Zasadzinski, J.; /IIT, Chicago; Ciovati, G.; Kneissel, P.; Reece, C.; Rimmer, R.; /Jefferson Lab; Gurevich, A.; /Natl. High Mag. Field Lab.; Cooley, L.; Wu, G.; /Fermilab; Pellin, M.; /Argonne

    2009-05-01T23:59:59.000Z

    We have begun using Atomic Layer Deposition (ALD) to synthesize a variety of surface coatings on coupons and cavities as part of an effort to produce rf structures with significantly better performance and yield than those obtained from bulk niobium, The ALD process offers the possibility of conformally coating complex cavity shapes with precise layered structures with tightly constrained morphology and chemical properties. Our program looks both at the metallurgy and superconducting properties of these coatings, and also their performance in working structures. Initial results include: (1) results from ALD coated cavities and coupons, (2) new evidence from point contact tunneling (PCT) showing magnetic oxides can be a significant limitation to high gradient operation, (3) a study of high pressure rinsing damage on niobium samples.

  12. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, James W. (108 Independent Blvd., Aiken, SC 29801)

    1993-01-01T23:59:59.000Z

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

  13. Atom-interferometry constraints on dark energy

    E-Print Network [OSTI]

    Hamilton, Paul; Haslinger, Philipp; Simmons, Quinn; Müller, Holger; Khoury, Justin

    2015-01-01T23:59:59.000Z

    If dark energy---which drives the accelerated expansion of the universe---consists of a new light scalar field, it might be detectable as a "fifth force" between normal-matter objects, in potential conflict with precision tests of gravity. There has, however, been much theoretical progress in developing theories with screening mechanisms, which can evade detection by suppressing forces in regions of high density, such as the laboratory. One prominent example is the chameleon field. We reduce the effect of this screening mechanism by probing the chameleon with individual atoms rather than bulk matter. Using a cesium matter-wave interferometer near a spherical mass in an ultra-high vacuum chamber, we constrain a wide class of dynamical dark energy theories. Our experiment excludes a range of chameleon theories that reproduce the observed cosmic acceleration.

  14. Atomic line emission analyzer for hydrogen isotopes

    DOE Patents [OSTI]

    Kronberg, J.W.

    1993-03-30T23:59:59.000Z

    Apparatus for isotopic analysis of hydrogen comprises a low pressure chamber into which a sample of hydrogen is introduced and then exposed to an electrical discharge to excite the electrons of the hydrogen atoms to higher energy states and thereby cause the emission of light on the return to lower energy states, a Fresnel prism made at least in part of a material anomalously dispersive to the wavelengths of interest for dispersing the emitted light, and a photodiode array for receiving the dispersed light. The light emitted by the sample is filtered to pass only the desired wavelengths, such as one of the lines of the Balmer series for hydrogen, the wavelengths of which differ slightly from one isotope to another. The output of the photodiode array is processed to determine the relative amounts of each isotope present in the sample. Additionally, the sample itself may be recovered using a metal hydride.

  15. Observation of recoil-induced resonances and electromagnetically induced absorption of diffuse light by cold atoms

    SciTech Connect (OSTI)

    Zhang Wenzhuo [Key Laboratory of Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100039 (China); Cheng Huadong; Wang Yuzhu [Key Laboratory of Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Liu Liang [Key Laboratory of Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China)

    2009-05-15T23:59:59.000Z

    In this paper we report an experiment on the observation of the recoil-induced resonances (RIR) and electromagnetically induced absorption (EIA) of cold {sup 87}Rb atoms in diffuse light. The pump light of the RIR and the EIA comes from the diffuse light in an integrating sphere, which also serves the cooling light. We measured the RIR and the EIA signal varying with the detuning of the diffuse laser light, and also measured the number and the temperature of the cold atoms at the different detunings. The mechanism of RIR and EIA in the configuration with diffuse-light pumping and laser probing are discussed, and the difference between the nonlinear spectra of cold atoms in a diffuse-light cooling system and in a magneto-optical trap is studied.

  16. Creation of effective magnetic fields in optical lattices: The Hofstadter butterfly for cold neutral atoms

    E-Print Network [OSTI]

    D. Jaksch; P. Zoller

    2003-04-04T23:59:59.000Z

    We investigate the dynamics of neutral atoms in a 2D optical lattice which traps two distinct internal states of the atoms in different columns. Two Raman lasers are used to coherently transfer atoms from one internal state to the other, thereby causing hopping between the different columns. By adjusting the laser parameters appropriately we can induce a non vanishing phase of particles moving along a closed path on the lattice. This phase is proportional to the enclosed area and we thus simulate a magnetic flux through the lattice. This setup is described by a Hamiltonian identical to the one for electrons on a lattice subject to a magnetic field and thus allows us to study this equivalent situation under very well defined controllable conditions. We consider the limiting case of huge magnetic fields -- which is not experimentally accessible for electrons in metals -- where a fractal band structure, the Hofstadter butterfly, characterizes the system.

  17. Towards a Re-definition of the Second Based on Optical Atomic Clocks

    E-Print Network [OSTI]

    Riehle, Fritz

    2015-01-01T23:59:59.000Z

    The rapid increase in accuracy and stability of optical atomic clocks compared to the caesium atomic clock as primary standard of time and frequency asks for a future re-definition of the second in the International System of Units (SI). The status of the optical clocks based on either single ions in radio-frequency traps or on neutral atoms stored in an optical lattice is described with special emphasis of the current work at the Physikalisch-Technische Bundesanstalt (PTB). Besides the development and operation of different optical clocks with estimated fractional uncertainties in the 10^-18 range, the supporting work on ultra-stable lasers as core elements and the means to compare remote optical clocks via transportable standards, optical fibers, or transportable clocks is reported. Finally, the conditions, methods and next steps are discussed that are the prerequisites for a future re-definition of the second.

  18. Single photon absorption by a single atom: from heralded absorption to polarization state mapping

    E-Print Network [OSTI]

    Nicolas Piro; Jürgen Eschner

    2015-02-19T23:59:59.000Z

    Together with photon emission, the absorption of a single photon by a single atom is a fundamental process in matter-light interaction that manifests its quantum mechanical nature. As an experimentally controlled process, it is a key tool for the realization of quantum technologies. In particular, in an atom/photon based quantum network scenario, in which localized atomic particles are used as quantum information processing nodes while photons are used as carriers of quantum information between distant nodes, controlling both emission and absorption of single photons by single atoms is required for quantum coherent state mapping between the two entities. Most experimental efforts to date have focused on establishing the control of single photon emission by single trapped atoms, and the implementation of quantum networking protocols using this interaction. In this chapter, we describe experimental efforts to control the process of single photon absorption by single trapped ions. We describe a series of experiments in which polarization entangled photon pairs, generated by a spontaneous parametric down-conversion source, are coupled to a single ion. First the source is operated to generate heralded single photons, and coincidences between the absorption event of one photon of the pair and the detection of the heralding partner photon are observed. We then show how polarization control in the process is established, leading to the manifestation of the photonic polarization entanglement in the absorption process. Finally, we introduce protocols in which this interaction scheme is harnessed to perform tasks in a quantum network, such as entanglement distribution among distant nodes of the network, and we demonstrate a specific protocol for heralded, high-fidelity photon-to-atom quantum state transfer.

  19. Etalon-induced Baseline Drift And Correction In Atom Flux Sensors Based On Atomic Absorption Spectroscopy

    SciTech Connect (OSTI)

    Du, Yingge; Chambers, Scott A.

    2014-10-20T23:59:59.000Z

    Atom flux sensors based on atomic absorption (AA) spectroscopy are of significant interest in thin film growth as they can provide unobtrusive, element specific, real-time flux sensing and control. The ultimate sensitivity and performance of the sensors are strongly affected by the long-term and short term baseline drift. Here we demonstrate that an etalon effect resulting from temperature changes in optical viewport housings is a major source of signal instability which has not been previously considered or corrected by existing methods. We show that small temperature variations in the fused silica viewports can introduce intensity modulations of up to 1.5%, which in turn significantly deteriorate AA sensor performance. This undesirable effect can be at least partially eliminated by reducing the size of the beam and tilting the incident light beam off the viewport normal.

  20. Atomic displacements due to spinspin repulsion in conjugated alternant hydrocarbons

    E-Print Network [OSTI]

    Benzi, Michele

    Atomic displacements due to spin­spin repulsion in conjugated alternant hydrocarbons Ernesto-induced atomic displacements in conjugated alt- ernant hydrocarbons. It appears to be responsible alternant hydrocarbons (CAHs) have played a fun- damental role in the development of theoretical chemistry

  1. atom molecular dynamics: Topics by E-print Network

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

    atom molecular dynamics First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Billion Atom Molecular Dynamics...

  2. atomic matter waves: Topics by E-print Network

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

    6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Propagation of atomic matter waves inside an atom wave guide Quantum Physics (arXiv)...

  3. atomic physics codes: Topics by E-print Network

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

    atomic physics codes First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 EXAM: "Atomic and Molecular...

  4. atomic energy agency: Topics by E-print Network

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

    atomic energy agency First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 International Atomic Energy Agency...

  5. atomic energy commission: Topics by E-print Network

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

    atomic energy commission First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Danish Atomic Energy...

  6. atomic energy research establishment: Topics by E-print Network

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

    atomic energy research establishment First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Danish Atomic...

  7. atomic energy programs: Topics by E-print Network

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

    energy programs First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Atomizer: A Dynamic Atomicity Checker...

  8. atomic number materials: Topics by E-print Network

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

    atomic number materials First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Atomic number fluctuations in a...

  9. Long range forces between atomic impurities in liquid helium

    E-Print Network [OSTI]

    Long range forces between atomic impurities in liquid helium J. Dupont-Roc Laboratoire Kastler in a polarizable medium. We show that atomic impurities in liquid helium may indeed realize repulsive forces embedded in liquid helium, super uid or not. Solid helium have also been used. Successful theoretical

  10. http://bos.sagepub.com/ Bulletin of the Atomic Scientists

    E-Print Network [OSTI]

    Mousseau, Timothy A.

    of the Atomic Scientists Timothy A. Mousseau and Anders P. Møller Chernobyl's wildlife Landscape portrait contaminants on Chernobyl's wildlife Timothy A. Mousseau and Anders P. Møller Abstract The Chernobyl accident,000 square kilometers of land. The Chernobyl Forum Report, an initiative of the International Atomic Energy

  11. Ris6 Report No. 145 Danish Atomic Energy Commission

    E-Print Network [OSTI]

    -29 June, 1966, in the Sagamore, Lake George, New York. #12;- 2 - CONTENTS Page Abstract 1 1. IntroductionRis6 Report No. 145 Danish Atomic Energy Commission Research Establishment Riso Joining Methods App. Gjellerup, »7, Sølvgade, Copenhagen K, Denmark Araltabl* m txehwi$t from: Library, Danish Atomic Energy

  12. o Ris Report No. 290 & Danish Atomic Energy Commission

    E-Print Network [OSTI]

    o Risø Report No. 290 Os r i O ts o & Danish Atomic Energy Commission £ Research Establishment Risø Electron Heating in a Single-ended Q-Machine by Hans L. Pécseli and Peter I. Petersen May 1973 Sales, Danitb Atomic Energy CommiMion, RJM, DK-4000 Roskilde, Denmark #12;UDC 533.9.07 May 1 973 Risø Report No

  13. Vacuum - induced stationary entanglement in radiatively coupled three - level atoms

    E-Print Network [OSTI]

    L. Derkacz; L. Jakobczyk

    2008-05-05T23:59:59.000Z

    We consider a pair of three - level atoms interacting with a common vacuum and analyze the process of entanglement production due to spontaneous emission. We show that in the case of closely separated atoms, collective damping can generate robust entanglement of the asymptotic states.

  14. Problems with Accurate Atomic Lfetime Measurements of Multiply Charged Ions

    SciTech Connect (OSTI)

    Trabert, E

    2009-02-19T23:59:59.000Z

    A number of recent atomic lifetime measurements on multiply charged ions have reported uncertainties lower than 1%. Such a level of accuracy challenges theory, which is a good thing. However, a few lessons learned from earlier precision lifetime measurements on atoms and singly charged ions suggest to remain cautious about the systematic errors of experimental techniques.

  15. Ris Report No. 304 Danish Atomic Energy Commission

    E-Print Network [OSTI]

    o o* i Risø Report No. 304 Danish Atomic Energy Commission Research Establishment Risø Metallurgy Atomic Energy Commission Research Establishment Risø METALLURGY DEPARTMENT PROGRESS REPORT for the Period of the Metallurgy Department at Risø, which for many years has done extensive work within several areas of nuclear

  16. Riv Report No. 200 Danish Atomic Energy Commission

    E-Print Network [OSTI]

    i Riv Report No. 200 Danish Atomic Energy Commission Research Establishment Risø Studies-1307 CoptnlHfm K, Damuk Avalhblt on rxchange from: Litary, DMU* Atomic Energy RiM, DK-4000 Rnk Species 78 35.4. Root Crops 81 3.2.5. Wild Plants 81 3.2.6. Allium Species 82 3.2.7. Comparison

  17. Towards new states of matter with atoms and photons

    E-Print Network [OSTI]

    QED = coupling between few material (atomic) and few electromagnetic degrees of freedom. Cavity atom-field quantum simulators. Hubbard models, spin models,... 2 #12;Motivation High control monitoring hybrid systems many- body systems beyond condensed matter paradigm models. 3 #12;Outline 1. Cavity QED in five

  18. Risd Report No. 205 J" Danish Atomic Energy Commission

    E-Print Network [OSTI]

    I Risd Report No. 205 J" Danish Atomic Energy Commission .1 * Research Establishment Risd Condition« in a Reactor Containment Building by W. M. Zak * and O. Walmod- Larsen Danish Atomic Energy - Otwock, Poland. #12;#12;- 8 - Contents Page Introduction 5 Release Method 11 Measurement Method 12

  19. Measurement of friction coefficients with the atomic force microscope

    E-Print Network [OSTI]

    Attard, Phil

    Measurement of friction coefficients with the atomic force microscope Phil Attard1, Johanna axial method for measuring the friction coefficient with the atomic force microscope is given measurement by measuring the difference between the constant compliance slopes of the extend and retract force

  20. Experimental Investigation of Excited-State Lifetimes in Atomic Ytterbium

    SciTech Connect (OSTI)

    Bowers, C.J.; Budker, D.; Commins, E.D.; DeMille, D.; Freedman, S.J.; Nguyen, A.-T.; Shang, S.-Q.; /UC, Berkeley; Zolotorev, M.; /SLAC

    2011-11-15T23:59:59.000Z

    Lifetimes of 21 excited states in atomic Yb were measured using time-resolved fluorescence detection following pulsed laser excitation. The lifetime of the 4f{sup 14}5d6s {sup 3}D{sub 1} state, which is of particular importance for a proposed study of parity nonconservation in atoms, was measured to be 380(30) ns.

  1. atomic hydrogen physisorbed: Topics by E-print Network

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

    atomic hydrogen physisorbed First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Recombination of atomic...

  2. atomic hydrogen density: Topics by E-print Network

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

    atomic hydrogen density First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 THE HYDROGEN ATOM REVISITED...

  3. atomic absorption analysis: Topics by E-print Network

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

    atomic absorption analysis First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Dressed-atom multiphoton...

  4. Efimov physics in bosonic atom-trimer scattering

    SciTech Connect (OSTI)

    Deltuva, A. [Centro de Fisica Nuclear da Universidade de Lisboa, P-1649-003 Lisboa (Portugal)

    2010-10-15T23:59:59.000Z

    Bosonic atom-trimer scattering is studied in the unitary limit using momentum-space equations for four-particle transition operators. The impact of the Efimov effect on the atom-trimer scattering observables is explored, and a number of universal relations is established. Positions and widths of tetramer resonances are determined. The trimer relaxation rate constant is calculated.

  5. Embrittlement of RPV steels; An atom probe tomography perspective

    SciTech Connect (OSTI)

    Miller, Michael K [ORNL; Russell, Kaye F [ORNL

    2007-01-01T23:59:59.000Z

    Atom probe tomography has played a key role in the understanding of the embrittlement of neutron irradiated reactor pressure vessel steels through the atomic level characterization of the microstructure. Atom probe tomography has been used to demonstrate the importance of the post weld stress relief treatment in reducing the matrix copper content in high copper alloys, the formation of {approx}-nm-diameter copper-, nickel-, manganese- and silicon-enriched precipitates during neutron irradiation in copper containing RPV steels, and the coarsening of these precipitates during post irradiation heat treatments. Atom probe tomography has been used to detect {approx}2-nm-diameter nickel-, silicon- and manganese-enriched clusters in neutron irradiated low copper and copper free alloys. Atom probe tomography has also been used to quantify solute segregation to, and precipitation on, dislocations and grain boundaries.

  6. Internal Spin Control, Squeezing and Decoherence in Ensembles of Alkali Atomic Spins

    E-Print Network [OSTI]

    Leigh M. Norris

    2014-10-01T23:59:59.000Z

    This dissertation studies spin squeezing, entanglement and decoherence in large ensembles of cold, trapped alkali atoms with hyperfine spin f interacting with optical fields. Restricting the state of each atom to a qutrit embedded in the 2f+1 dimensional hyperfine spin enables us to efficiently model the coherent and dissipative dynamics of the ensemble. This formalism also allows us to explore the effects of local control on the internal hyperfine spins of the atoms. State preparation using such control increases the entangling power of the atom-light interface for f>1/2. Subsequent control of the internal spins converts entanglement into metrologically relevant spin squeezing. In the case of squeezing by quantum nondemolition measurement, we employ a numerical search to find state preparations that maximize spin squeezing in the presence of decoherence. Dissipative dynamics on our system include optical pumping due to spontaneous emission. While most works ignore optical pumping or treat it phenomenologically, we employ a master equation derived from first principles. This work is extended to the case of an atomic ensemble interacting with a non-homogeneous paraxial probe. The geometries of the ensemble and the probe are optimized to maximize both spatial mode matching and spin squeezing.

  7. Assessment of the release of atomic Na from a burning black liquor droplet using quantitative PLIF

    SciTech Connect (OSTI)

    Saw, Woei L.; Nathan, Graham J. [Centre for Energy Technology, The Environment Institute, School of Mechanical Engineering, The University of Adelaide, SA 5005 (Australia); Ashman, Peter J.; Alwahabi, Zeyad T. [Centre for Energy Technology, The Environment Institute, School of Chemical Engineering, The University of Adelaide, SA 5005 (Australia)

    2009-07-15T23:59:59.000Z

    The quantitative measurement of atomic sodium (Na) release, at high concentration, from a burning black liquor droplet has been demonstrated using a planar laser-induced fluorescence (PLIF) technique, corrected for fluorescence trapping. The local temperature of the particle was measured to be approximately 1700 C, at a height of 10 mm above a flat flame burner. The PLIF technique was used to assess the temporal release of atomic Na from the combustion of black liquor and compare it with the Na concentration in the remaining smelt. A first-order model was made to provide insight using a simple Plug Flow Reactor model based on the independently measured concentration of residual Na in the smelt as a function of time. This model also required the dilution ratio of the combustion products in the flat flame entrained into the plume gas from the black liquor particle to be estimated. The key findings of these studies are: (i) the peak concentration of atomic Na from the combustion of the black liquor droplets is around 1.4 ppm; (ii) very little atomic Na is present during the drying, devolatilisation or char combustion stages; and (iii) the presence of atomic Na during smelt phase dominates over that from the other combustion stages. (author)

  8. Atomic Classification of 6D SCFTs

    E-Print Network [OSTI]

    Jonathan J. Heckman; David R. Morrison; Tom Rudelius; Cumrun Vafa

    2015-05-04T23:59:59.000Z

    We use F-theory to classify possibly all six-dimensional superconformal field theories (SCFTs). This involves a two step process: We first classify all possible tensor branches allowed in F-theory (which correspond to allowed collections of contractible spheres) and then classify all possible configurations of seven-branes wrapped over them. We describe the first step in terms of "atoms" joined into "radicals" and "molecules," using an analogy from chemistry. The second step has an interpretation via quiver-type gauge theories constrained by anomaly cancellation. A very surprising outcome of our analysis is that all of these tensor branches have the structure of a linear chain of intersecting spheres with a small amount of possible decoration at the two ends. The resulting structure of these SCFTs takes the form of a generalized quiver consisting of ADE-type nodes joined by conformal matter. A collection of highly non-trivial examples involving E8 small instantons probing an ADE singularity is shown to have an F-theory realization. This yields a classification of homomorphisms from ADE subgroups of SU(2) into E8 in purely geometric terms, largely matching results obtained in the mathematics literature from an intricate group theory analysis.

  9. Hydrogen-like atoms in relativistic QED

    E-Print Network [OSTI]

    Martin Könenberg; Oliver Matte; Edgardo Stockmeyer

    2012-07-21T23:59:59.000Z

    In this review we consider two different models of a hydrogenic atom in a quantized electromagnetic field that treat the electron relativistically. The first one is a no-pair model in the free picture, the second one is given by the semi-relativistic Pauli-Fierz Hamiltonian. For both models we discuss the semi-boundedness of the Hamiltonian, the strict positivity of the ionization energy, and the exponential localization in position space of spectral subspaces corresponding to energies below the ionization threshold. Moreover, we prove the existence of degenerate ground state eigenvalues at the bottom of the spectrum of the Hamiltonian in both models. All these results hold true, for arbitrary values of the fine-structure constant and the ultra-violet cut-off, and for a general class of electrostatic potentials including the Coulomb potential with nuclear charges less than (sometimes including) the critical charges without radiation field. Apart from a detailed discussion of diamagnetic inequalities in QED (which are applied to study the semi-boundedness) all results stem from earlier articles written by the authors. While a few proofs are merely sketched, we streamline earlier proofs or present alternative arguments at many places.

  10. Electron-impact ionization of atomic hydrogen

    SciTech Connect (OSTI)

    Baertschy, Mark D.

    2000-02-14T23:59:59.000Z

    Since the invention of quantum mechanics, even the simplest example of collisional breakup in a system of charged particles, e{sup {minus}} + H {r_arrow} H{sup +} + e{sup {minus}} + e{sup {minus}}, has stood as one of the last unsolved fundamental problems in atomic physics. A complete solution requires calculating the energies and directions for a final state in which three charged particles are moving apart. Advances in the formal description of three-body breakup have yet to lead to a viable computational method. Traditional approaches, based on two-body formalisms, have been unable to produce differential cross sections for the three-body final state. Now, by using a mathematical transformation of the Schrodinger equation that makes the final state tractable, a complete solution has finally been achieved, Under this transformation, the scattering wave function can be calculated without imposing explicit scattering boundary conditions. This approach has produced the first triple differential cross sections that agree on an absolute scale with experiment as well as the first ab initio calculations of the single differential cross section.

  11. MATERIALS WITH COMPLEX ELECTRONIC/ATOMIC STRUCTURES

    SciTech Connect (OSTI)

    D. M. PARKIN; L. CHEN; ET AL

    2000-09-01T23:59:59.000Z

    We explored both experimentally and theoretically the behavior of materials at stresses close to their theoretical strength. This involves the preparation of ultra fine scale structures by a variety of fabrication methods. In the past year work has concentrated on wire drawing of in situ composites such as Cu-Ag and Cu-Nb. Materials were also fabricated by melting alloys in glass and drawing them into filaments at high temperatures by a method known as Taylor wire technique. Cu-Ag microwires have been drawn by this technique to produce wires 10 {micro}m in diameter that consist of nanoscale grains of supersaturated solid solution. Organogels formed from novel organic gelators containing cholesterol tethered to squaraine dyes or trans-stilbene derivatives have been studied from several different perspectives. The two types of molecules are active toward several organic liquids, gelling in some cases at w/w percentages as low as 0.1. While relatively robust, acroscopically dry gels are formed in several cases, studies with a variety of probes indicate that much of the solvent may exist in domains that are essentially liquid-like in terms of their microenvironment. The gels have been imaged by atomic force microscopy and conventional and fluorescence microscopy, monitoring both the gelator fluorescence in the case of the stilbene-cholesterol gels and, the fluorescence of solutes dissolved in the solvent. Remarkably, our findings show that several of the gels are composed of similarly appearing fibrous structures visible at the nano-, micro-, and macroscale.

  12. The New Element Californium (Atomic Number 98)

    DOE R&D Accomplishments [OSTI]

    Seaborg, G. T.; Thompson, S. G.; Street, K. Jr.; Ghiroso, A.

    1950-06-19T23:59:59.000Z

    Definite identification has been made of an isotope of the element with atomic number 98 through the irradiation of Cm{sup 242} with about 35-Mev helium ions in the Berkeley Crocker Laboratory 60-inch cyclotron. The isotope which has been identified has an observed half-life of about 45 minutes and is thought to have the mass number 244. The observed mode of decay of 98{sup 244} is through the emission of alpha-particles, with energy of about 7.1 Mev, which agrees with predictions. Other considerations involving the systematics of radioactivity in this region indicate that it should also be unstable toward decay by electron capture. The chemical separation and identification of the new element was accomplished through the use of ion exchange adsorption methods employing the resin Dowex-50. The element 98 isotope appears in the eka-dysprosium position on elution curves containing berkelium and curium as reference points--that is, it precedes berkelium and curium off the column in like manner that dysprosium precedes terbium and gadolinium. The experiments so far have revealed only the tripositive oxidation state of eka-dysprosium character and suggest either that higher oxidation states are not stable in aqueous solutions or that the rates of oxidation are slow. The successful identification of so small an amount of an isotope of element 98 was possible only through having made accurate predictions of the chemical and radioactive properties.

  13. Carbon based thirty six atom spheres

    DOE Patents [OSTI]

    Piskoti, Charles R.; Zettl, Alex K.; Cohen, Marvin L.; Cote, Michel; Grossman, Jeffrey C.; Louie, Steven G.

    2005-09-06T23:59:59.000Z

    A solid phase or form of carbon is based on fullerenes with thirty six carbon atoms (C.sub.36). The C.sub.36 structure with D.sub.6h symmetry is one of the two most energetically favorable, and is conducive to forming a periodic system. The lowest energy crystal is a highly bonded network of hexagonal planes of C.sub.36 subunits with AB stacking. The C.sub.36 solid is not a purely van der Waals solid, but has covalent-like bonding, leading to a solid with enhanced structural rigidity. The solid C.sub.36 material is made by synthesizing and selecting out C.sub.36 fullerenes in relatively large quantities. A C.sub.36 rich fullerene soot is produced in a helium environment arc discharge chamber by operating at an optimum helium pressure (400 torr). The C.sub.36 is separated from the soot by a two step process. The soot is first treated with a first solvent, e.g. toluene, to remove the higher order fullerenes but leave the C.sub.36. The soot is then treated with a second solvent, e.g. pyridine, which is more polarizable than the first solvent used for the larger fullerenes. The second solvent extracts the C.sub.36 from the soot. Thin films and powders can then be produced from the extracted C.sub.36. Other materials are based on C.sub.36 fullerenes, providing for different properties.

  14. Teleportation of an atomic momentum state

    E-Print Network [OSTI]

    Qamar, S.; Zhu, S. Y.; Zubairy, M. Suhail.

    2003-01-01T23:59:59.000Z

    be extended in terms of the Bell basis uC6&5 1A2 ~ u1p0&u0&16u2p0&u1&1), ~4! uF6&5 1A2 ~ u1p0&u1&16u2p0&u0&1), ~5! and is given by the following: uC&5 12 @ uC1&~cau1&21cbu0&2)1uC2&~cau1&22cbu0&2) 1uF1&~cau0&21cbu1&2)1uF2&~cau0&22cbu1&2)]. ~6! The next...-NOT logic gates, the Bell states defined by Eqs. ~4! and ~5! evolve in the following way: uC6&? 1A2 ~ u0&16u1&1)u1p0&, ~10! and uF6&? 1A2 ~ u1&16u0&1)u2p0&. ~11! Now the Bell states are disentangled and the atoms can be detected in the two directions...

  15. Atomic Oxygen in the Comae of Comets

    E-Print Network [OSTI]

    Anita L. Cochran

    2008-07-03T23:59:59.000Z

    We report on the detection of atomic oxygen lines in the spectra of 8 comets. These forbidden lines are a result of the photodissociation of the parent oxygen-bearing species directly into an excited state. We used high resolution spectra obtained at the McDonald Observatory 2.7m telescope to resolve the cometary oxygen lines from the telluric oxygen lines and from other cometary emissions. We find that the relative intensities of the two red lines (6300.304 and 6363.776A) are consistent with theory. The green line (5577.339A) has an intensity which is about 10% of the sum of the intensities of the two red lines. We show that collisional quenching may be important in the inner coma. If we assume the relative excitation rates of potential parents which have appeared in the literature, then H2O would be the parent of the cometary green oxygen line. However, those rates have been questioned. We measured the width of the three oxygen lines and find that the green line is wider than either of the two red lines. The finding of a wider line could imply a different parent for the green and red lines. However, the constancy of the green to red line flux ratio suggests the parent is the same for these lines but that the exciting photons have different energies.

  16. Cavity-Modified Collective Rayleigh Scattering of Two Atoms

    E-Print Network [OSTI]

    René Reimann; Wolfgang Alt; Tobias Kampschulte; Tobias Macha; Lothar Ratschbacher; Natalie Thau; Seokchan Yoon; Dieter Meschede

    2015-01-15T23:59:59.000Z

    We report on the observation of cooperative radiation of exactly two neutral atoms strongly coupled to the single mode field of an optical cavity, which is close to the lossless-cavity limit. Monitoring the cavity output power, we observe constructive and destructive interference of collective Rayleigh scattering for certain relative distances between the two atoms. Because of cavity backaction onto the atoms, the cavity output power for the constructive two-atom case ($N=2$) is almost equal to the single-emitter case ($N=1$), which is in contrast to free-space where one would expect an $N^2$ scaling of the power. These effects are quantitatively explained by a classical model as well as by a quantum mechanical model based on Dicke states. We extract information on the relative phases of the light fields at the atom positions and employ advanced cooling to reduce the jump rate between the constructive and destructive atom configurations. Thereby we improve the control over the system to a level where the implementation of two-atom entanglement schemes involving optical cavities becomes realistic.

  17. A Single-Photon Server with Just One Atom

    E-Print Network [OSTI]

    Markus Hijlkema; Bernhard Weber; Holger P. Specht; Simon C. Webster; Axel Kuhn; Gerhard Rempe

    2007-02-05T23:59:59.000Z

    Neutral atoms are ideal objects for the deterministic processing of quantum information. Entanglement operations have been performed by photon exchange or controlled collisions. Atom-photon interfaces were realized with single atoms in free space or strongly coupled to an optical cavity. A long standing challenge with neutral atoms, however, is to overcome the limited observation time. Without exception, quantum effects appeared only after ensemble averaging. Here we report on a single-photon source with one-and-only-one atom quasi permanently coupled to a high-finesse cavity. Quasi permanent refers to our ability to keep the atom long enough to, first, quantify the photon-emission statistics and, second, guarantee the subsequent performance as a single-photon server delivering up to 300,000 photons for up to 30 seconds. This is achieved by a unique combination of single-photon generation and atom cooling. Our scheme brings truly deterministic protocols of quantum information science with light and matter within reach.

  18. Atoms.inp Archive: Crystallographic Data from GSECARS

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Newville, Matthew

    The Atoms.inp Archive is a collection of crystallographic data for use in XAFS analysis. The crystallographic data is stored as atoms.inp files, which contain all the information necessary to describe the crystal, and can be used by the program ATOMS to generate feff.inp files. These files can then be used by the FEFF program [See http://leonardo.phys.washington.edu/feff/] to calculate a theoretical XAFS spectrum for the crystal. This archive exists because it can take a considerable amount of time to locate a suitable reference for a model structure to use for making theoretical XAFS standards. Even then, references sometimes give non-standard or incomplete crystallographic notation that ATOMS has difficulty interpreting. All of this means that getting a reliable atoms.inp file can take quite a bit of effort. It is hoped that this collection of well-documented and well-tested atoms.inp files will eliminate much of the work in creating theoretical XAFS standards from FEFF. [Taken from http://cars9.uchicago.edu/~newville/adb/]. The collection currently has more than 200 crystal structures, 2748 data files, and it continues to expand. The collection is related to the UWXAFS Project [http://depts.washington.edu/uwxafs/] and to the work of the Consortium for Advanced Radiation Sources (CARS). After searching the Archive, a user may also choose to run the web version of ATOMS software.

  19. Absorption spectrum of Ca atoms attached to $^4$He nanodroplets

    E-Print Network [OSTI]

    Alberto Hernando; Manuel Barranco; Marek Kro?nicki; Ricardo Mayol; Martí Pi

    2007-11-12T23:59:59.000Z

    Within density functional theory, we have obtained the structure of $^4$He droplets doped with neutral calcium atoms. These results have been used, in conjunction with newly determined {\\it ab-initio} $^1\\Sigma$ and $^1\\Pi$ Ca-He pair potentials, to address the $4s4p$ $^1$P$_1 \\leftarrow 4s^2$ $^1$S$_0$ transition of the attached Ca atom, finding a fairly good agreement with absorption experimental data. We have studied the drop structure as a function of the position of the Ca atom with respect of the center of mass of the helium moiety. The interplay between the density oscillations arising from the helium intrinsic structure and the density oscillations produced by the impurity in its neighborhood plays a role in the determination of the equilibrium state, and hence in the solvation properties of alkaline earth atoms. In a case of study, the thermal motion of the impurity within the drop surface region has been analyzed in a semi-quantitative way. We have found that, although the atomic shift shows a sizeable dependence on the impurity location, the thermal effect is statistically small, contributing by about a 10% to the line broadening. The structure of vortices attached to the calcium atom has been also addressed, and its effect on the calcium absorption spectrum discussed. At variance with previous theoretical predictions, we conclude that spectroscopic experiments on Ca atoms attached to $^4$He drops will be likely unable to detect the presence of quantized vortices in helium nanodrops.

  20. Light pulse atom interferometry at short interrogation times for inertial navigation

    E-Print Network [OSTI]

    Butts, David LaGrange

    2012-01-01T23:59:59.000Z

    Light pulse atom interferometry with cold atoms is a promising inertial sensing technology for high accuracy navigation. At present, laboratory atom interferometers match or surpass state of the art mechanical and optical ...