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1

The Quantum Hall Effect in Graphene  

E-Print Network (OSTI)

We investigate the quantum Hall effect in graphene. We argue that in graphene in presence of an external magnetic field there is dynamical generation of mass by a rearrangement of the Dirac sea. We show that the mechanism breaks the lattice valley degeneracy only for the $n=0$ Landau levels and leads to the new observed $\

Paolo Cea

2011-01-29T23:59:59.000Z

2

First Observation of Spin Hall Effect in a Quantum Gas Is Step ...  

Science Conference Proceedings (OSTI)

First Observation of Spin Hall Effect in a Quantum Gas Is Step Toward 'Atomtronics'. ... The spin Hall effect in a quantum gas. ...

2013-06-11T23:59:59.000Z

3

Robert B. Laughlin and the Fractional Quantum Hall Effect  

NLE Websites -- All DOE Office Websites (Extended Search)

Robert B. Laughlin and the Fractional Quantum Hall Effect Robert B. Laughlin and the Fractional Quantum Hall Effect Resources with Additional Information Robert B. Laughlin Photo Courtesy of LLNL Robert B. Laughlin shared the 1998 Nobel Prize in Physics with Horst L. Störmer and Daniel C. Tsui for 'their discovery of a new form of quantum fluid with fractionally charged excitations'. ' ... [I]n 1982 ... Störmer and Tsui discovered the effect. In 1983, Laughlin, then at the Lawrence Livermore National Laboratory, provided the theoretical explanation of the effect in terms of fractionally charged particles. It was a "confluence of things from engineering that prepared me for understanding the fractional quantum Hall effect and coming up with an explanation," Laughlin said during a television interview at Stanford. ...

4

Quantum Anomalous Hall Effect in Hg_1-yMn_yTe Quantum Wells  

SciTech Connect

The quantum Hall effect is usually observed when the two-dimensional electron gas is subjected to an external magnetic field, so that their quantum states form Landau levels. In this work we predict that a new phenomenon, the quantum anomalous Hall effect, can be realized in Hg{sub 1-y}Mn{sub y}Te quantum wells, without the external magnetic field and the associated Landau levels. This effect arises purely from the spin polarization of the Mn atoms, and the quantized Hall conductance is predicted for a range of quantum well thickness and the concentration of the Mn atoms. This effect enables dissipationless charge current in spintronics devices.

Liu, Chao-Xing; /Tsinghua U., Beijing /Stanford U., Phys. Dept.; Qi, Xiao-Liang; /Stanford U., Phys. Dept.; Dai, Xi; Fang, Zhong; /Beijing, Inst. Phys.; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

2010-03-19T23:59:59.000Z

5

The Quantum Spin Hall Effect: Theory and Experiment  

SciTech Connect

The search for topologically non-trivial states of matter has become an important goal for condensed matter physics. Recently, a new class of topological insulators has been proposed. These topological insulators have an insulating gap in the bulk, but have topologically protected edge states due to the time reversal symmetry. In two dimensions the helical edge states give rise to the quantum spin Hall (QSH) effect, in the absence of any external magnetic field. Here we review a recent theory which predicts that the QSH state can be realized in HgTe/CdTe semiconductor quantum wells. By varying the thickness of the quantum well, the band structure changes from a normal to an 'inverted' type at a critical thickness d{sub c}. We present an analytical solution of the helical edge states and explicitly demonstrate their topological stability. We also review the recent experimental observation of the QSH state in HgTe/(Hg,Cd)Te quantum wells. We review both the fabrication of the sample and the experimental setup. For thin quantum wells with well width d{sub QW} < 6.3 nm, the insulating regime shows the conventional behavior of vanishingly small conductance at low temperature. However, for thicker quantum wells (d{sub QW} > 6.3 nm), the nominally insulating regime shows a plateau of residual conductance close to 2e{sup 2}/h. The residual conductance is independent of the sample width, indicating that it is caused by edge states. Furthermore, the residual conductance is destroyed by a small external magnetic field. The quantum phase transition at the critical thickness, d{sub c} = 6.3 nm, is also independently determined from the occurrence of a magnetic field induced insulator to metal transition.

Konig, Markus; Buhmann, Hartmut; Molenkamp, Laurens W.; /Wurzburg U.; Hughes, Taylor L.; /Stanford U., Phys. Dept.; Liu, Chao-Xing; /Tsinghua U., Beijing /Stanford U., Phys. Dept.; Qi, Xiao-Liang; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

2010-03-19T23:59:59.000Z

6

The Quantum Spin Hall Effect: Theory and Experiment  

Science Conference Proceedings (OSTI)

The search for topologically non-trivial states of matter has become an important goal for condensed matter physics. Recently, a new class of topological insulators has been proposed. These topological insulators have an insulating gap in the bulk, but have topologically protected edge states due to the time reversal symmetry. In two dimensions the helical edge states give rise to the quantum spin Hall (QSH) effect, in the absence of any external magnetic field. Here we review a recent theory which predicts that the QSH state can be realized in HgTe/CdTe semiconductor quantum wells. By varying the thickness of the quantum well, the band structure changes from a normal to an 'inverted' type at a critical thickness d{sub c}. We present an analytical solution of the helical edge states and explicitly demonstrate their topological stability. We also review the recent experimental observation of the QSH state in HgTe/(Hg,Cd)Te quantum wells. We review both the fabrication of the sample and the experimental setup. For thin quantum wells with well width d{sub QW} 6.3 nm), the nominally insulating regime shows a plateau of residual conductance close to 2e{sup 2}/h. The residual conductance is independent of the sample width, indicating that it is caused by edge states. Furthermore, the residual conductance is destroyed by a small external magnetic field. The quantum phase transition at the critical thickness, d{sub c} = 6.3 nm, is also independently determined from the occurrence of a magnetic field induced insulator to metal transition.

Konig, Markus; Buhmann, Hartmut; Molenkamp, Laurens W.; /Wurzburg U.; Hughes, Taylor L.; /Stanford U., Phys. Dept.; Liu, Chao-Xing; /Tsinghua U., Beijing /Stanford U., Phys. Dept.; Qi, Xiao-Liang; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

2010-03-19T23:59:59.000Z

7

PREPRINT QUASIPARTICLE AGGREGATION I N THE FRACTIONAL QUANTUM HALL EFFECT  

NLE Websites -- All DOE Office Websites (Extended Search)

91618 91618 PREPRINT QUASIPARTICLE AGGREGATION I N THE FRACTIONAL QUANTUM HALL EFFECT R. B. Laughlin This paper was prepared for submittal to the Proceedings of the 17th International Conference on the Physics of Semi conductors San Francisco, California August 6-10, 1984 October 10, 1984 This is a preprint of a paper intended for publication in a journal or proceedings. Since changes may be made before publication, this preprint is made available with the un- derstanding that it will not be cited or reproduced without the permission of the author. DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency Thereof, nor any of their employees,

8

Toward theory of quantum Hall effect in graphene  

E-Print Network (OSTI)

We analyze a gap equation for the propagator of Dirac quasiparticles and conclude that in graphene in a magnetic field, the order parameters connected with the quantum Hall ferromagnetism dynamics and those connected with the magnetic catalysis dynamics necessarily coexist (the latter have the form of Dirac masses and correspond to excitonic condensates). This feature of graphene could lead to important consequences, in particular, for the existence of gapless edge states. Solutions of the gap equation corresponding to recently experimentally discovered novel plateaus in graphene in strong magnetic fields are described.

E. V. Gorbar; V. P. Gusynin; V. A. Miransky

2007-10-18T23:59:59.000Z

9

Quantum anomalous Hall effect with cold atoms trapped in a square lattice  

E-Print Network (OSTI)

We propose an experimental scheme to realize the quantum anomalous Hall effect in an anisotropic square optical lattice which can be generated from available experimental setups of double-well lattices with minor modifications. A periodic gauge potential induced by atom-light interaction is introduced to give a Peierls phase for the nearest-neighbor site hopping. The quantized anomalous Hall conductivity is investigated by calculating the Chern number as well as the chiral gapless edge states of our system. Furthermore, we show in detail the feasability for its experimental detection through light Bragg scattering of the edge and bulk states with which one can determine the topological phase transition from usual insulating phase to quantum anomalous Hall phase.

Liu, Xiong-Jun; Liu, Xin; Wu, Congjun; Sinova, Jairo

2010-01-01T23:59:59.000Z

10

Excitonic gap, phase transition, and quantum Hall effect in graphene  

E-Print Network (OSTI)

We suggest that physics underlying the recently observed removal of sublattice and spin degeneracies in graphene in a strong magnetic field describes a phase transition connected with the generation of an excitonic gap. The experimental form of the Hall conductivity is reproduced and the main characteristics of the dynamics are described. Predictions of the behavior of the gap as a function of temperature and a gate voltage are made.

V. P. Gusynin; V. A. Miransky; S. G. Sharapov; I. A. Shovkovy

2006-05-12T23:59:59.000Z

11

Electron quantum optics in quantum Hall edge channels  

E-Print Network (OSTI)

In this paper, we review recent developments in the emerging field of electron quantum optics, stressing analogies and differences with the usual case of photon quantum optics. Electron quantum optics aims at preparing, manipulating and measuring coherent single electron excitations propagating in ballistic conductors such as the edge channels of a 2DEG in the integer quantum Hall regime. Because of the Fermi statistics and the presence of strong interactions, electron quantum optics exhibits new features compared to the usual case of photon quantum optics. In particular, it provides a natural playground to understand decoherence and relaxation effects in quantum transport.

Grenier, Charles; Fve, Gwendal; Degiovanni, Pascal

2011-01-01T23:59:59.000Z

12

Electron quantum optics in quantum Hall edge channels  

E-Print Network (OSTI)

In this paper, we review recent developments in the emerging field of electron quantum optics, stressing analogies and differences with the usual case of photon quantum optics. Electron quantum optics aims at preparing, manipulating and measuring coherent single electron excitations propagating in ballistic conductors such as the edge channels of a 2DEG in the integer quantum Hall regime. Because of the Fermi statistics and the presence of strong interactions, electron quantum optics exhibits new features compared to the usual case of photon quantum optics. In particular, it provides a natural playground to understand decoherence and relaxation effects in quantum transport.

Charles Grenier; Rmy Herv; Gwendal Fve; Pascal Degiovanni

2011-02-02T23:59:59.000Z

13

Fractional Quantum Hall States in Graphene  

E-Print Network (OSTI)

We quantum mechanically analyze the fractional quantum Hall effect in graphene. This will be done by building the corresponding states in terms of a potential governing the interactions and discussing other issues. More precisely, we consider a system of particles in the presence of an external magnetic field and take into account of a specific interaction that captures the basic features of the Laughlin series \

Ahmed Jellal; Bellati Malika

2008-05-15T23:59:59.000Z

14

Transport through quantum spin Hall insulator/metal junctions in graphene ribbons  

Science Conference Proceedings (OSTI)

Quantum spin Hall insulator/metal interfaces are formed in graphene ribbons with intrinsic spin-orbit coupling by selectively doping two regions creating a potential step. For a clean graphene ribbon, the transmission of the topological edge states through ... Keywords: Graphene ribbons, Quantum spin Hall effect, Quantum transport, pn Junctions

Elsa Prada, Georgo Metalidis

2013-06-01T23:59:59.000Z

15

Decoherence induced by magnetic impurities in a quantum hall system  

SciTech Connect

Scattering by magnetic impurities is known to destroy coherence of electron motion in metals and semiconductors. We investigate the decoherence introduced in a single act of electron scattering by a magnetic impurity in a quantum Hall system. For this, we introduce a fictitious nonunitary scattering matrix for electrons that reproduces the exactly calculated scattering probabilities. The strength of decoherence is identified by the deviation of eigenvalues of the product from unity. Using the fictitious scattering matrix, we estimate the width of the metallic region at the quantum Hall effect inter-plateau transition and its dependence on the exchange coupling strength and the degree of polarization of magnetic impurities.

Kagalovsky, V. [Shamoon College of Engineering (Israel); Chudnovskiy, A. L., E-mail: alexander.chudnovskiy@gmail.com [Universitat Hamburg, I. Institut fuer Theoretische Physik (Germany)

2013-04-15T23:59:59.000Z

16

Single electron quantum tomography in quantum Hall edge channels  

E-Print Network (OSTI)

We propose a quantum tomography protocol to measure single electron coherence in quantum Hall edge channels and therefore access for the first time the wave function of single electron excitations propagating in ballistic quantum conductors. Its implementation would open the way to quantitative studies of single electron decoherence and would provide a quantitative tool for analyzing single to few electron sources. We show how this protocol could be implemented using ultrahigh sensitivity noise measurement schemes.

Grenier, Charles; Bocquillon, Erwann; Parmentier, Franois D; Plaais, Bernard; Berroir, Jean-Marc; Fve, Gwendal; Degiovanni, Pascal; 10.1088/1367-2630/13/9/093007

2011-01-01T23:59:59.000Z

17

Single electron quantum tomography in quantum Hall edge channels  

E-Print Network (OSTI)

We propose a quantum tomography protocol to measure single electron coherence in quantum Hall edge channels and therefore access for the first time the wave function of single electron excitations propagating in ballistic quantum conductors. Its implementation would open the way to quantitative studies of single electron decoherence and would provide a quantitative tool for analyzing single to few electron sources. We show how this protocol could be implemented using ultrahigh sensitivity noise measurement schemes.

Charles Grenier; Rmy Herv; Erwann Bocquillon; Franois D. Parmentier; Bernard Plaais; Jean-Marc Berroir; Gwendal Fve; Pascal Degiovanni

2010-10-11T23:59:59.000Z

18

Collective Modes of Quantum Hall Stripes  

E-Print Network (OSTI)

The collective modes of striped phases in a quantum Hall system are computed using the time-dependent Hartree-Fock approximation. Uniform stripe phases are shown to be unstable to the formation of modulations along the stripes, so that within the Hartree-Fock approximation the groundstate is a stripe crystal. Such crystalline states are generically gapped at any finite wavevector; however, in the quantum Hall system the interactions of modulations among different stripes is found to be remarkably weak, leading to an infinite collection of collective modes with immeasurably small gaps. The resulting long wavelength behavior is derivable from an elastic theory for smectic liquid crystals. Collective modes for the phonon branch are computed throughout the Brillouin zone, as are spin wave and magnetoplasmon modes. A soft mode in the phonon spectrum is identified for partial filling factors sufficiently far from 1/2, indicating a second order phase transition. The modes contain several other signatures that should be experimentally

R. Ct; H. A. Fertig

2008-01-01T23:59:59.000Z

19

Fractional Quantization of the Hall Effect  

DOE R&D Accomplishments (OSTI)

The Fractional Quantum Hall Effect is caused by the condensation of a two-dimensional electron gas in a strong magnetic field into a new type of macroscopic ground state, the elementary excitations of which are fermions of charge 1/m, where m is an odd integer. A mathematical description is presented.

Laughlin, R. B.

1984-02-27T23:59:59.000Z

20

Spin hall effect in paramagnetic thin films  

E-Print Network (OSTI)

Spintronics, an abbreviation of spin based electronics and also known as magneto electronics, has attracted a lot of interest in recent years. It aims to explore the role of electrons spins in building next generation electric devices. Using electrons spins rather than electrons charges may allow faster, lower energy cost devices. Spin Hall Effect is an important subfield of spintronics. It studies spin current, spin transport, and spin accumulation in paramagnetic systems. It can further understanding of quantum physics, device physics, and may also provide insights for spin injection, spin detection and spin manipulation in the design of the next generation spintronics devices. In this experimental work, two sets of experiments were prepared to detect the Spin Hall Effect in metallic systems. The first set of experiments aims to extract Spin Hall Effect from Double Hall Effect in micrometer size metal thin film patterns. Our experiments proved that the Spin Hall Effect signal was much smaller than the theoretically calculated value due to higher electrical resistivity in evaporated thin films. The second set of experiments employs a multi-step process. It combines micro fabrication and electrochemical method to fabricate a perpendicular ferromagnet rod as a spin injector. Process description and various techniques to improve the measurement sensitivity are presented. Measurement results in aluminum, gold and copper are presented in Chapters III, IV and V. Some new experiments are suggested in Chapters V and VI.

Xu, Huachun

2008-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Hall-effect arc protector  

DOE Patents (OSTI)

The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored. 2 figs.

Rankin, R.A.; Kotter, D.K.

1997-05-13T23:59:59.000Z

22

Hall-effect arc protector  

DOE Patents (OSTI)

The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored.

Rankin, Richard A. (Ammon, ID); Kotter, Dale K. (Shelley, ID)

1997-01-01T23:59:59.000Z

23

Hall effect in superconducting films  

E-Print Network (OSTI)

Near the superconducting phase transition, fluctuations significantly modify the electronic transport properties. Here we study the fluctuation corrections to the Hall conductivity in disordered films, extending previous ...

Michaeli, Karen

24

Spin Hall effects for cold atoms in a light induced gauge potential  

SciTech Connect

We propose an experimental scheme to observe spin Hall effects with cold atoms in a light induced gauge potential. Under an appropriate configuration, the cold atoms moving in a spatially varying laser field experience an effective spin-dependent gauge potential. Through numerical simulation, we demonstrate that such a gauge field leads to observable spin Hall currents under realistic conditions. We also discuss the quantum spin Hall state in an optical lattice.

Zhu, Shi-Liang; /Michigan U., MCTP /South China Normal U.; Fu, Hao; /Michigan U., MCTP; Wu, C.-J.; /Santa Barbara, KITP; Zhang, S.-C.; /Stanford U., Phys. Dept.; Duan, L.-M. /Michigan U., MCTP

2010-03-16T23:59:59.000Z

25

Imaging fractional incompressible stripes in integer quantum Hall systems  

E-Print Network (OSTI)

Transport experiments provide conflicting evidence on the possible existence of fractional order within integer quantum Hall systems. In fact integer edge states sometimes behave as monolithic objects with no inner structure, while other experiments clearly highlight the role of fractional substructures. Recently developed low-temperature scanning probe techniques offer today an opportunity for a deeper-than-ever investigation of spatial features of such edge systems. Here we use scanning gate microscopy and demonstrate that fractional features were unambiguously observed in every integer quantum Hall constriction studied. We present also an experimental estimate of the width of the fractional incompressible stripes corresponding to filling factors 1/3, 2/5, 3/5, and 2/3. Our results compare well with predictions of the edge-reconstruction theory.

Nicola Paradiso; Stefan Heun; Stefano Roddaro; Lucia Sorba; Fabio Beltram; Giorgio Biasiol; L. N. Pfeiffer; K. W. West

2012-05-02T23:59:59.000Z

26

Electron-Hole Entanglement in a Quantum Spin Hall Insulator  

E-Print Network (OSTI)

We demonstrate that entangled electron-hole pairs can be produced and detected in a quantum spin Hall insulator with a constriction that allows for a weak inter-edge tunneling. A violation of a Bell inequality, which can be constructed in terms of low-frequency nonlocal current-current correlations, serves as a detection of the entanglement. We show that the maximum violation of a Bell inequality can be naturally achieved in this setup, without a need to fine tune tunneling parameters. This may provide a viable route to producing spin entanglement in the absence of any correlations and pairing, where spin-to-charge conversion is enabled by the helical edge structure of a quantum spin Hall insulator.

Koji Sato; Mircea Trif; Yaroslav Tserkovnyak

2013-08-06T23:59:59.000Z

27

From insulator to quantum Hall liquid at low magnetic fields  

E-Print Network (OSTI)

We have performed low-temperature transport measurements on a GaAs twodimensional electron system at low magnetic fields. Multiple temperatureindependent points and accompanying oscillations are observed in the longitudinal resistivity between the low-field insulator and the quantum Hall liquid. The amplitudes of these oscillations can be well described by conventional Shubnikov-de Haas theory, and our experimental results therefore support the existence of an intermediate metallic regime between the low-field insulator and quantum Hall liquid. 1 Two-dimensional (2D) phase transitions have attracted a great deal of interest recently [111]. To date, despite many existing experimental and theoretical studies on 2D phase transitions, there are still some interesting but unresolved issues. In particular, it is still under debate whether a direct transition from an insulator (I) to a high Landau level filling factor (? ? 3) quantum Hall (QH) state at low magnetic fields B is a genuine phase transition. Experimentally, a single approximately temperature (T)-independent point in

Tsai-yu Huanga; C. -t. Lianga; Gil-ho Kimb; C. F. Huangc; Chao-ping Huanga

2006-01-01T23:59:59.000Z

28

Proposal for a Datta-Das transistor in the quantum Hall regime  

E-Print Network (OSTI)

We propose a resonant spin-field-effect transistor for chiral spin-resolved edge states in the integer quantum Hall effect with Rashba spin-orbit interaction. It employs a periodic array of voltage-controlled top gates that locally modulate the Rashba spin-orbit interaction. Strong resonant spin-field effect is achieved when the array periodicity matches the inverse of the wave-vector difference of the two chiral states involved. Well-known techniques of separately contacting the edge states make it possible to selectively populate and read out the edge states, allowing full spin readout. The resonant nature of the spin-field effect and the adiabatic character of the edge states guarantee a high degree of robustness with respect to disorder. Our device represents the quantum Hall version of the all-electrical Datta-Das spin-field effect transistor.

Luca Chirolli; D. Venturelli; F. Taddei; Rosario Fazio; V. Giovannetti

2011-11-02T23:59:59.000Z

29

Imaging of quantum Hall states in ultracold atomic gases  

SciTech Connect

We examine off-resonant light scattering from ultracold atoms in the quantum Hall regime. When the light scattering is spin dependent, we show that images formed in the far field can be used to distinguish states of the system. The spatial dependence of the far-field images is determined by the two-particle spin-correlation functions, which the images are related to by a transformation. Quasiholes in the system appear in images of the density formed by collecting the scattered light with a microscope, where the quasihole statistics are revealed by the reduction in density at the quasihole position.

Douglas, James S.; Burnett, Keith [University of Sheffield, Western Bank, Sheffield S10 2TN (United Kingdom)

2011-11-15T23:59:59.000Z

30

Geometric Spin Hall Effect of Light  

E-Print Network (OSTI)

We describe a novel phenomenon occurring when a polarized Gaussian beam of light is observed in a Cartesian reference frame whose axes are not parallel to the direction of propagation of the beam. Such phenomenon amounts to an intriguing spin-dependent shift of the position of the center of the beam, with manners akin to the spin Hall effect of light. We demonstrate that this effect is unavoidable when the light beam possesses a nonzero transverse angular momentum.

Andrea Aiello; Christoph Marquardt; Gerd Leuchs

2009-02-26T23:59:59.000Z

31

Intra-Landau level polarization effect for a striped Hall gas  

E-Print Network (OSTI)

We calculate the polarization function including only intra-Landau level correlation effects of striped Hall gas. Using the polarization function, the dielectric function, the dispersion of the plasmon and the correlation energy are computed in a random phase approximation (RPA) and generalized random phase approximation (GRPA). The plasmon becomes anisotropic and gapless owing to the anisotropy of the striped Hall gas and two dimensionality of the quantum Hall system. The plasmon approximately agrees with the phonon derived before by the single mode approximation. The (G)RPA correlation energy is compared with other numerical calculations.

T. Aoyama; K. Ishikawa; Y. Ishizuka; N. Maeda

2003-12-10T23:59:59.000Z

32

Scaling laws and electron properties in Hall effect thrusters.  

E-Print Network (OSTI)

??All satellites need a propulsion system for orbit correction maneuvers. Electric Hall effect thrusters are an interesting technology for space applications. The big advantage compared (more)

Dannenmayer, Kthe

2012-01-01T23:59:59.000Z

33

Effective Field Theory of Fractional Quantized Hall Nematics  

SciTech Connect

We present a Landau-Ginzburg theory for a fractional quantized Hall nematic state and the transition to it from an isotropic fractional quantum Hall state. This justifies Lifshitz-Chern-Simons theory - which is shown to be its dual - on a more microscopic basis and enables us to compute a ground state wave function in the symmetry-broken phase. In such a state of matter, the Hall resistance remains quantized while the longitudinal DC resistivity due to thermally-excited quasiparticles is anisotropic. We interpret recent experiments at Landau level filling factor {nu} = 7/3 in terms of our theory.

Mulligan, Michael; /MIT, LNS; Nayak, Chetan; /Station Q, UCSB; Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC

2012-06-06T23:59:59.000Z

34

First Observation of the Hall Effect in a Bose-Einstein ...  

Science Conference Proceedings (OSTI)

First Observation of the Hall Effect in a Bose-Einstein Condensate. From NIST Tech Beat: June 19, 2012. ... Observation of a superfluid Hall effect. ...

2013-07-08T23:59:59.000Z

35

Subpicosecond spin relaxation in GaAsSb multiple quantum wells K. C. Hall,a)  

E-Print Network (OSTI)

Subpicosecond spin relaxation in GaAsSb multiple quantum wells K. C. Hall,a) S. W. Leonard, and H quantum wells are measured at 295 K using time-resolved circular dichroism induced by 1.5 m, 100 fs pulses times shorter than those in InGaAs and InGaAsP wells with similar band gaps. The shorter relaxation

Van Driel, Henry M.

36

Hall effect measurements on InAs nanowires  

Science Conference Proceedings (OSTI)

We have processed Hall contacts on InAs nanowires grown by molecular beam epitaxy using an electron beam lithography process with an extremely high alignment accuracy. The carrier concentrations determined from the Hall effect measurements on these nanowires are lower by a factor of about 4 in comparison with those measured by the common field-effect technique. The results are used to evaluate quantitatively the charging effect of the interface and surface states.

Bloemers, Ch.; Grap, T.; Lepsa, M. I.; Moers, J.; Gruetzmacher, D.; Lueth, H. [Peter Gruenberg Institute (PGI-9) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Juelich GmbH, 52425 Juelich (Germany); Trellenkamp, St. [Peter Gruenberg Institute (PGI-8) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Juelich GmbH, 52425 Juelich (Germany); Schaepers, Th. [Peter Gruenberg Institute (PGI-9) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Juelich GmbH, 52425 Juelich (Germany); II. Physikalisches Institut, RWTH Aachen University, 52056 Aachen (Germany)

2012-10-08T23:59:59.000Z

37

Experimental Observation of the Inverse Spin Hall Effect at Room Temperature  

SciTech Connect

We observe the inverse spin Hall effect in a two-dimensional electron gas confined in Al-GaAs/InGaAs quantum wells. Specifically, they find that an inhomogeneous spin density induced by the optical injection gives rise to an electric current transverse to both the spin polarization and its gradient. The spin Hall conductivity can be inferred from such a measurement through the Einstein relation and the onsager relation, and is found to have the order of magnitude of 0.5(e{sup 2}/h). The observation is made at the room temperature and in samples with macroscopic sizes, suggesting that the inverse spin Hall effects is a robust macroscopic transport phenomenon.

Liu, Baoli; Shi, Junren; Wang, Wenxin; Zhao, Hongming; Li, Dafang; /Beijing, Inst. Phys.; Zhang, Shoucheng; /Stanford U., Phys. Dept.; Xue, Qikun; Chen, Dongmin; /Beijing, Inst. Phys.

2010-03-16T23:59:59.000Z

38

Effects of Segmented Electrode in Hall Current Plasma Thrusters  

DOE Green Energy (OSTI)

Segmented electrodes with a low secondary electron emission are shown to alter significantly plasma flow in the ceramic channel of the Hall thruster. The location of the axial acceleration region relative to the magnetic field can be moved. The radial potential distribution can also be altered near the channel walls. A hydrodynamic model shows that these effects are consistent with a lower secondary electron emission of the segmented electrode as compared to ceramic channel walls.

Y. Raitses; M. Keidar; D. Staack; N.J. Fisch

2001-12-03T23:59:59.000Z

39

Hall effect in a strong magnetic field: Direct comparisons of compressible magnetohydrodynamics and the reduced Hall magnetohydrodynamic equations  

SciTech Connect

In this work we numerically test a model of Hall magnetohydrodynamics in the presence of a strong mean magnetic field: the reduced Hall magnetohydrodynamic model (RHMHD) derived by [Gomez et al., Phys. Plasmas 15, 102303 (2008)] with the addition of weak compressible effects. The main advantage of this model lies in the reduction of computational cost. Nevertheless, up until now the degree of agreement with the original Hall MHD system and the range of validity in a regime of turbulence were not established. In this work direct numerical simulations of three-dimensional Hall MHD turbulence in the presence of a strong mean magnetic field are compared with simulations of the weak compressible RHMHD model. The results show that the degree of agreement is very high (when the different assumptions of RHMHD, such as spectral anisotropy, are satisfied). Nevertheless, when the initial conditions are isotropic but the mean magnetic field is maintained strong, the results differ at the beginning but asymptotically reach a good agreement at relatively short times. We also found evidence that the compressibility still plays a role in the dynamics of these systems, and the weak compressible RHMHD model is able to capture these effects. In conclusion the weak compressible RHMHD model is a valid approximation of the Hall MHD turbulence in the relevant physical context.

Martin, L. N.; Dmitruk, P. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina) and IFIBA, CONICET, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Gomez, D. O. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina) and IFIBA, CONICET, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Instituto de Astronomia y Fisica del Espacio, Ciudad Universitaria, 1428 Buenos Aires (Argentina)

2010-11-15T23:59:59.000Z

40

U(1) X U(1) XI Z(2) Chern-Simons theory and Z(4) parafermion fractional quantum Hall states  

E-Print Network (OSTI)

We study U(1)U(1)?Z2 Chern-Simons theory with integral coupling constants (k,l) and its relation to certain non-Abelian fractional quantum Hall (FQH) states. For the U(1)U(1)?Z2 Chern-Simons theory, we show how to compute ...

Barkeshli, Maissam

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Resistively-Detected NMR Studies of Quantum Hall Systems Katsuyoshi Kodera, Hisashi Takado, Akira Endo, Yoshiaki Hashimoto, Shingo  

E-Print Network (OSTI)

Resistively-Detected NMR Studies of Quantum Hall Systems Katsuyoshi Kodera, Hisashi Takado, Akira, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 Abstract. The resistively-detected NMR. The NMR lineshape in this region exhibits a dip-peak structure (dispersive lineshape). The anomalous

Katsumoto, Shingo

42

Orbitronics: the Intrinsic Orbital Hall Effect in p-Doped Silicon  

SciTech Connect

The spin Hall effect depends crucially on the intrinsic spin-orbit coupling of the energy band. Because of the smaller spin-orbit coupling in silicon, the spin Hall effect is expected to be much reduced. We show that the electric field in p-doped silicon can induce a dissipationless orbital current in a fashion reminiscent of the spin Hall effect. The vertex correction due to impurity scattering vanishes and the effect is therefore robust against disorder. The orbital Hall effect can lead to the accumulation of local orbital momentum at the edge of the sample, and can be detected by the Kerr effect.

Bernevig, B.Andrei; Hughes, Taylor L.; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

2010-01-15T23:59:59.000Z

43

Physics of Hall-effect thruster by particle model  

SciTech Connect

A realistic three-dimensional fully kinetic particle simulation of a Hall-effect thruster discharge has been developed. The model consists of a Particle-in-Cell methodology tracking electrons, Xe{sup +} and Xe{sup ++} ions in their selfconsistent electric field. A detailed secondary electron emission from lateral walls is also implemented in addition with electron-atom and electron-ion volume collisions. The model is able to capture the most relevant features of axial, radial and azimuthal behaviors of the start-up transient and steady state phases detecting inverted sheaths and azimuthal modulation in the acceleration region. The model has the potentiality to investigate the driving mechanisms at the origin of the electron anomalous cross-field transport.

Taccogna, Francesco; Minelli, Pierpaolo; Capitelli, Mario; Longo, Savino [Istituto di Metodologie Inorganiche e dei Plasmi (IMIP), CNR, via Amendola 122/D 70126 Bari (Italy); Dipartimento di Chimica, Universita degli Studi di Bari Aldo Moro, via Orabona 4 70126 Bari (Italy)

2012-11-27T23:59:59.000Z

44

Normal-state Hall effect in YBa[sub 2]Cu[sub 3[minus][ital x  

Science Conference Proceedings (OSTI)

We have measured the normal-state Hall effect on single crystals of YBa[sub 2]Cu[sub 3[minus][ital x

Lan, M.D.; Liu, J.Z.; Jia, Y.X.; Zhang, L.; Shelton, R.N. (Department of Physics, University of California, Davis, California 95616 (United States))

1994-01-01T23:59:59.000Z

45

Effect of a plume reduction in segmented electrode Hall thruster  

DOE Green Energy (OSTI)

A segmented electrode, which is placed at the thruster exit, is shown to affect thruster operation in several ways, whether the electrode produce low emission current or no emission current, although there appear to be advantages to the more emissive segmented electrode. Measured by plume divergence, the performance of Hall thruster operation, even with only one power supply, can approach or surpass that of non segmented operation over a range of parameter regimes, including the low gas rate regime. This allows the flexibility in operation of segmented electrode thrusters in variable thrust regimes.

Raitses, Y.; Dorf, L.A.; Livak, A.A.; Fisch, N.J.

2000-01-27T23:59:59.000Z

46

Edge Mode Combinations in the Entanglement Spectra of Non-Abelian Fractional Quantum Hall States on the Torus  

E-Print Network (OSTI)

We present a detailed analysis of bi-partite entanglement in the non-Abelian Moore-Read fractional quantum Hall state of bosons and fermions on the torus. In particular, we show that the entanglement spectra can be decomposed into intricate combinations of different sectors of the conformal field theory describing the edge physics, and that the edge level counting and tower structure can be microscopically understood by considering the vicinity of the thin-torus limit. We also find that the boundary entropy density of the Moore-Read state is markedly higher than in the Laughlin states investigated so far. Despite the torus geometry being somewhat more involved than in the sphere geometry, our analysis and insights may prove useful when adopting entanglement probes to other systems that are more easily studied with periodic boundary conditions, such as fractional Chern insulators and lattice problems in general.

Zhao Liu; Emil J. Bergholtz; Heng Fan; Andreas M. Laeuchli

2011-09-09T23:59:59.000Z

47

Quantum Zeno effect: Quantum shuffling and Markovianity  

E-Print Network (OSTI)

The behavior displayed by a quantum system when it is perturbed by a series of von Neumann measurements along time is analyzed. Because of the similarity between this general process with giving a deck of playing cards a shuffle, here it is referred to as quantum shuffling, showing that the quantum Zeno and anti-Zeno effects emerge naturally as two time limits. Within this framework, a connection between the gradual transition from anti-Zeno to Zeno behavior and the appearance of an underlying Markovian dynamics is found. Accordingly, although a priori it might result counterintuitive, the quantum Zeno effect corresponds to a dynamical regime where any trace of knowledge on how the unperturbed system should evolve initially is wiped out (very rapid shuffling). This would explain why the system apparently does not evolve or decay for a relatively long time, although it eventually undergoes an exponential decay. By means of a simple working model, conditions characterizing the shuffling dynamics have been determined, which can be of help to understand and to devise quantum control mechanisms in a number of processes from the atomic, molecular and optical physics.

A. S. Sanz; C. Sanz-Sanz; T. Gonzalez-Lezana; O. Roncero; S. Miret-Artes

2011-12-16T23:59:59.000Z

48

Quantum Effect Materials: Methods of Fabrication of Quantum ... - TMS  

Science Conference Proceedings (OSTI)

Session A: Quantum Effect Materials: Methods of Fabrication of Quantum Dots. Session ... Nanometer size semiconductor crystallites show a striking evolution of ...

49

Extracting the Chern number from the dynamics of a Fermi gas: Implementing a quantum Hall bar for cold atoms  

E-Print Network (OSTI)

We propose a scheme to measure the quantized Hall conductivity of an ultracold Fermi gas initially prepared in a topological (Chern) insulating phase, and driven by a constant force. We show that the time evolution of the center of mass, after releasing the cloud, provides a direct and clear signature of the topologically invariant Chern number. We discuss the validity of this scheme, highlighting the importance of driving the system with a sufficiently strong force to displace the cloud over measurable distances while avoiding band-mixing effects. The unusual shapes of the driven atomic cloud are qualitatively discussed in terms of a semi-classical approach.

Alexandre Dauphin; Nathan Goldman

2013-05-16T23:59:59.000Z

50

Quantum Conductance Project/Graphene-Based Quantum ...  

Science Conference Proceedings (OSTI)

Quantum Conductance Project/Graphene-Based Quantum Metrology. Summary: ... Graphene Hall bar developed at NIST by undergraduate students. ...

2011-10-03T23:59:59.000Z

51

Dynamical Scaling of the Quantum Hall Plateau Transition F. Hohls,1,* U. Zeitler,1  

E-Print Network (OSTI)

.43.Fj Phase transitions between different phases of matter are frequently met in nature, e.g., in ice- and second-order transitions. In a first-order transition, the two phases coexist; in a second. Different from these types of classical phase transitions are quantum phase transitions. Strictly speak- ing

Hohls, Frank

52

Effective equations for the quantum pendulum from momentous quantum mechanics  

SciTech Connect

In this work we study the quantum pendulum within the framework of momentous quantum mechanics. This description replaces the Schroedinger equation for the quantum evolution of the system with an infinite set of classical equations for expectation values of configuration variables, and quantum dispersions. We solve numerically the effective equations up to the second order, and describe its evolution.

Hernandez, Hector H.; Chacon-Acosta, Guillermo [Universidad Autonoma de Chihuahua, Facultad de Ingenieria, Nuevo Campus Universitario, Chihuahua 31125 (Mexico); Departamento de Matematicas Aplicadas y Sistemas, Universidad Autonoma Metropolitana-Cuajimalpa, Artificios 40, Mexico D. F. 01120 (Mexico)

2012-08-24T23:59:59.000Z

53

Gregory Hall  

NLE Websites -- All DOE Office Websites (Extended Search)

Gregory Hall Gregory Hall Senior Chemist Chemistry Department Building 555 Brookhaven National Laboratory P.O. Box 5000 Upton, NY 11973-5000 Phone: (631) 344-4376 FAX: (631) 344-5815 e-mail Gas-Phase Molecular Dynamics Research Interests Chemical Physics: Molecular dynamics, spectroscopy, photochemistry and kinetics. Applications of high resolution spectroscopy to molecular dynamics; Doppler spectroscopy for the measurement of product correlations in bimolecular and unimolecular reactions. Statistical and dynamical models of vector correlations; experimental tests of unimolecular rate theory. Multiple surface reactions; coherent effects in multiple path reactions; measurement and interpretation of photofragment orientation. Collision-induced electronic transitions. Double-resonance spectroscopy for collision studies of energy and polarization transfer.

54

Design and characterization of a low cost dual differential proving ring force sensor utilizing Hall-effect sensors  

E-Print Network (OSTI)

A novel dual differential hall-effect based proving ring force sensor has been designed, manufactured, and tested. Strain gauge based force sensors are among the most common methods of measuring static and dynamic forces, ...

Rivest, Christopher W. (Christopher Warren)

2006-01-01T23:59:59.000Z

55

The Initiation, Propagation and Termination of Anode Effects in Hall ...  

Science Conference Proceedings (OSTI)

Retrofit of a Combined Breaker Feeder with a Chisel Bath Contact Detection System to Reduce Anode Effect Frequency in a Potroom Simulating Traffic in a...

56

All-optical Hall effect by the dynamic toroidal moment in a cavity-based metamaterial  

E-Print Network (OSTI)

Dynamic dipolar toroidal response is demonstrated by an optical plasmonic metamaterial composed of double disks. This response with a hotspot of localized E-field concentration is a well-behaved toroidal cavity mode that exhibits a large Purcell factor due to its deep-subwavelength mode volume. All-optical Hall effect (photovoltaic) due to this optical toroidal moment is demonstrated numerically, in mimicking the magnetoelectric effect in multiferroic systems. The result shows a promising avenue to explore various optical phenomena associated with this intriguing dynamic toroidal moment.

Dong, Zheng-Gao; Yin, Xiaobo; Li, Jiaqi; Lu, Changgui; Zhang, Xiang

2013-01-01T23:59:59.000Z

57

Quantum Annealing and Quantum Fluctuation Effect in Frustrated Ising Systems  

E-Print Network (OSTI)

Quantum annealing method has been widely attracted attention in statistical physics and information science since it is expected to be a powerful method to obtain the best solution of optimization problem as well as simulated annealing. The quantum annealing method was incubated in quantum statistical physics. This is an alternative method of the simulated annealing which is well-adopted for many optimization problems. In the simulated annealing, we obtain a solution of optimization problem by decreasing temperature (thermal fluctuation) gradually. In the quantum annealing, in contrast, we decrease quantum field (quantum fluctuation) gradually and obtain a solution. In this paper we review how to implement quantum annealing and show some quantum fluctuation effects in frustrated Ising spin systems.

Tanaka, Shu

2012-01-01T23:59:59.000Z

58

Empirical electron cross-field mobility in a Hall effect thruster  

Science Conference Proceedings (OSTI)

Electron transport across the magnetic field in Hall effect thrusters is still an open question. Models have so far assumed 1/B{sup 2} or 1/B scaling laws for the 'anomalous' electron mobility, adjusted to reproduce the integrated performance parameters of the thruster. We show that models based on such mobility laws predict very different ion velocity distribution functions (IVDF) than measured by laser induced fluorescence (LIF). A fixed spatial mobility profile, obtained by analysis of improved LIF measurements, leads to much better model predictions of thruster performance and IVDF than 1/B{sup 2} or 1/B mobility laws for discharge voltages in the 500-700 V range.

Garrigues, L. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse Cedex 9 (France); Perez-Luna, J.; Lo, J.; Hagelaar, G. J. M.; Boeuf, J. P. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse Cedex 9 (France); CNRS, LAPLACE, F-31062 Toulouse (France); Mazouffre, S. [ICARE (Institut de Combustion, Aerothermique, Reactivite et Environnement) IC, Avenue de la Recherche Scientifique, 45071 Orleans (France)

2009-10-05T23:59:59.000Z

59

Fractional quantum Hall states of few bosonic atoms in geometric gauge fields  

E-Print Network (OSTI)

We employ the exact diagonalization method to analyze the possibility of generating strongly correlated states in two-dimensional clouds of ultracold bosonic atoms which are subjected to a geometric gauge field created by coupling two internal atomic states to a laser beam. Tuning the gauge field strength, the system undergoes stepwise transitions between different ground states, which we describe by analytical trial wave functions, amongst them the Pfaffian, the Laughlin, and a Laughlin quasiparticle many-body state. The adiabatic following of the center of mass movement by the lowest energy dressed internal state, is lost by the mixing of the second internal state. This mixture can be controlled by the intensity of the laser field. The non-adiabaticity is inherent to the considered setup, and is shown to play the role of circular asymmetry. We study its influence on the properties of the ground state of the system. Its main effect is to reduce the overlap of the numerical solutions with the analytical trial expressions by occupying states with higher angular momentum. Thus, we propose generalized wave functions arising from the Laughlin and Pfaffian wave function by including components, where extra Jastrow factors appear, while preserving important features of these states. We analyze quasihole excitations over the Laughlin and generalized Laughlin states, and show that they possess effective fractional charge and obey anyonic statistics. Finally, we study the energy gap over the Laughlin state as the number of particles is increased keeping the chemical potential fixed. The gap is found to decrease as the number of particles is increased, indicating that the observability of the Laughlin state is restricted to a small number of particles.

B. Juli-Daz; T. Gra; N. Barbern; M. Lewenstein

2011-11-03T23:59:59.000Z

60

A novel numerical analysis of Hall Effect Thruster and its application in simultaneous design of thruster and optimal low-thrust trajectory.  

E-Print Network (OSTI)

??Hall Effect Thrusters (HETs) are a form of electric propulsion device which uses external electrical energy to produce thrust. When compared to various other electric (more)

Kwon, Kybeom

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Fundamental Quantum Effects from a Quantum-Optics Perspective  

E-Print Network (OSTI)

This article provides a brief overview of some fundamental effects of quantum fields under extreme conditions. For the Schwinger mechanism, Hawking radiation, and the Unruh effect, analogies to quantum optics are discussed, which might help to approach to these phenomena from an experimental point of view.

Ralf Schtzhold

2010-04-14T23:59:59.000Z

62

Nuclear quantum effects in water  

E-Print Network (OSTI)

In this work, a path integral Car-Parrinello molecular dynamics simulation of liquid water is performed. It is found that the inclusion of nuclear quantum effects systematically improves the agreement of first principles simulations of liquid water with experiment. In addition, the proton momentum distribution is computed utilizing a recently developed open path integral molecular dynamics methodology. It is shown that these results are in good agreement with neutron Compton scattering data for liquid water and ice.

Joseph A. Morrone; Roberto Car

2008-03-25T23:59:59.000Z

63

Quantum effect on luminosity-redshift relation  

E-Print Network (OSTI)

There are many different proposals for a theory of quantum gravity. Even leaving aside the fundamental difference among theories such as the string theory and the non-perturbative quantum gravity, we are still left with many ambiguities (and/or parameters to be determined) with regard to the choice of variables, the choice of related groups, etc. Loop quantum gravity is also in such a state. It is interesting to search for experimental observables to distinguish these quantum schemes. This paper investigates the loop quantum gravity effect on luminosity-redshift relation. The quantum bounce behavior of loop quantum cosmology is found to result in multivalued correspondence in luminosity-redshift relation. And the detail multivalued behavior can tell the difference of different quantum parameters. The inverse volume quantum correction does not result in bounce behavior in this model, but affects luminosity-redshift relation also significantly.

Li-Fang Li; Jian-Yang Zhu

2010-06-28T23:59:59.000Z

64

Quantum Field Theory in Graphene  

E-Print Network (OSTI)

This is a short non-technical introduction to applications of the Quantum Field Theory methods to graphene. We derive the Dirac model from the tight binding model and describe calculations of the polarization operator (conductivity). Later on, we use this quantity to describe the Quantum Hall Effect, light absorption by graphene, the Faraday effect, and the Casimir interaction.

Fialkovsky, I V

2011-01-01T23:59:59.000Z

65

Quantum Field Theory in Graphene  

E-Print Network (OSTI)

This is a short non-technical introduction to applications of the Quantum Field Theory methods to graphene. We derive the Dirac model from the tight binding model and describe calculations of the polarization operator (conductivity). Later on, we use this quantity to describe the Quantum Hall Effect, light absorption by graphene, the Faraday effect, and the Casimir interaction.

I. V. Fialkovsky; D. V. Vassilevich

2011-11-13T23:59:59.000Z

66

The Quantum Zeno Effect -- Watched Pots in the Quantum World  

E-Print Network (OSTI)

In the 5th century B.C.,the philosopher and logician Zeno of Elea posed several paradoxes which remained unresolved for over two thousand five hundred years. The $20^{th}$ century saw some resolutions to Zeno's mind boggling problems. This long journey saw many significant milestones in the form of discoveries like the tools of converging series and theories on infinite sets in mathematics. In recent times, the Zeno effect made an intriguing appearance in a rather unlikely place - a situation involving the time evolution of a quantum system, which is subject to "observations" over a period of time. Leonid Khalfin working in the former USSR in the 1960s and ECG Sudarshan and B. Misra at the University of Texas, Austin, first drew attention to this problem. In 1977, ECG Sudarshan and B. Misra published a paper on the quantum Zeno effect, called "The Zeno's paradox in quantum theory". Their fascinating result revealed the bizarre workings of the quantum world. Misra and Sudarshan's 1977 paper activated over two decades of theoretical and experimental explorations into the subject and still continues to evoke a lot of interest. In the following, the quantum Zeno effect is described and a brief outline of some of the work following Misra and Sudarshan's paper is given. The quantum Zeno effect is yet another example of the myriad unimaginable possibilities that lie waiting in the magical world of the quantum.

Anu Venugopalan

2012-11-15T23:59:59.000Z

67

Correlation between the extraordinary Hall constant and electrical resistivity minima in Co-rich metallic glasses  

E-Print Network (OSTI)

The Hall effect has been studied in some Co-rich ferromagnetic metallic glasses which show resistivity (rho) minima at low temperatures. It is found that the extraordinary Hall constant (R-s) shows a corresponding minimum. The scaling relation R(s)similar torho(n) holds with nsimilar or equal to2 showing the dominance of quantum transport in these high-resistive disordered systems. The temperature dependences of magnetization and electrical resistivity are also interpreted in terms of existing theories.

Majumdar, AK; Khatua, PK; Rathnayaka, KDD; Naugle, Donald G.

2004-01-01T23:59:59.000Z

68

NMR analogues of the quantum Zeno effect  

E-Print Network (OSTI)

We describe Nuclear Magnetic Resonance (NMR) demonstrations of the quantum Zeno effect, and discuss briefly how these are related to similar phenomena in more conventional NMR experiments.

Li Xiao; Jonathan A. Jones

2005-06-28T23:59:59.000Z

69

Quantum Computing and Lie Theory Feynman's suggestion that the only effective way to model quantum phe-  

E-Print Network (OSTI)

Quantum Computing and Lie Theory Feynman's suggestion that the only effective way to model quantum phe- nomena on a computer would be to build a computer that made use of quantum mechanics was one of the cornerstones of the birth of quantum com- puting. In his later years he studied both classical and quantum

D'Agnolo, Andrea

70

Quantum interference effect and electric field domain formation in quantum well infrared photodetectors  

E-Print Network (OSTI)

Quantum interference effect and electric field domain formation in quantum well infrared April 1995 An observation of quantum interference effect in photocurrent spectra of a weakly coupled bound-to-continuum multiple quantum well photodetector is reported. This effect persists even at high

71

Generalized correlation functions for conductance fluctuations and the mesoscopic spin Hall effect  

E-Print Network (OSTI)

We study the spin-Hall conductance fluctuations in ballistic mesoscopic systems. We obtain universal expressions for the spin and charge current fluctuations, cast in terms of current-current autocorrelation functions. We show that the latter are conveniently parametrized as deformed Lorentzian shape lines, functions of an external applied magnetic field and the Fermi energy. We find that the charge current fluctuations show quite unique statistical features at the symplectic-unitary crossover regime. Our findings are based on an evaluation of the generalized transmission coefficients correlation functions within the stub model and are amenable to experimental test.

J. G. G. S. Ramos; A. L. R. Barbosa; D. Bazeia; M. S. Hussein; C. H. Lewenkopf

2012-12-09T23:59:59.000Z

72

Clean Cities: Trev Hall  

NLE Websites -- All DOE Office Websites (Extended Search)

About About Printable Version Share this resource Send a link to Clean Cities: Trev Hall to someone by E-mail Share Clean Cities: Trev Hall on Facebook Tweet about Clean Cities: Trev Hall on Twitter Bookmark Clean Cities: Trev Hall on Google Bookmark Clean Cities: Trev Hall on Delicious Rank Clean Cities: Trev Hall on Digg Find More places to share Clean Cities: Trev Hall on AddThis.com... Goals & Accomplishments Partnerships Hall of Fame Contacts Trev Hall Clean Cities Regional Manager Trev Hall is the point of contact for Clean Cities' coalitions in Alabama, Florida, Georgia, Mississippi, North Carolina, South Carolina, and Tennessee. His responsibilities include facilitating the efforts of the Clean Cities coalitions to increase the use of alternative fuels and

73

Quantum plasma effects in the classical regime  

E-Print Network (OSTI)

For quantum effects to be significant in plasmas it is often assumed that the temperature over density ratio must be small. In this paper we challenge this assumption by considering the contribution to the dynamics from the electron spin properties. As a starting point we consider a multicomponent plasma model, where electrons with spin up and spin down are regarded as different fluids. By studying the propagation of Alfv\\'{e}n wave solitons we demonstrate that quantum effects can survive in a relatively high-temperature plasma. The consequences of our results are discussed.

G. Brodin; M. Marklund; G. Manfredi

2008-02-01T23:59:59.000Z

74

Modelling, simulation and analysis of low-cost direct torque control of PMSM using hall-effect sensors  

E-Print Network (OSTI)

This thesis focuses on the development of a novel Direct Torque Control (DTC) scheme for permanent magnet (PM) synchronous motors (surface and interior types) in the constant torque region with the help of cost-effective hall-effect sensors. This method requires no DC-link sensing, which is a mandatory matter in the conventional DTC drives, therefore it reduces the cost of a conventional DTC of a permanent magnet (PM) synchronous motor and also removes common problems including; resistance change effect, low speed and integration drift. Conventional DTC drives require at least one DC-link voltage sensor (or two on the motor terminals) and two current sensors because of the necessary estimation of position, speed, torque, and stator flux in the stationary reference frame. Unlike the conventional DTC drive, the proposed method uses the rotor reference frame because the rotor position is provided by the three hall-effect sensors and does not require expensive voltage sensors. Moreover, the proposed algorithm takes the acceleration and deceleration of the motor and torque disturbances into account to improve the speed and torque responses. The basic theory of operation for the proposed topology is presented. A mathematical model for the proposed DTC of the PMSM topology is developed. A simulation program written in MATLAB/SIMULINK?® is used to verify the basic operation (performance) of the proposed topology. The mathematical model is capable of simulating the steady-state, as well as dynamic response even under heavy load conditions (e.g. transient load torque at ramp up). It is believed that the proposed system offers a reliable and low-cost solution for the emerging market of DTC for PMSM drives. Finally the proposed drive, considering the constant torque region operation, is applied to the agitation part of a laundry washing machine (operating in constant torque region) for speed performance comparison with the current low-cost agitation cycle speed control technique used by washing machine companies around the world.

Ozturk, Salih Baris

2005-12-01T23:59:59.000Z

75

Effect of trapping in degenerate quantum plasmas  

SciTech Connect

In the present work we consider the effect of trapping as a microscopic process in a plasma consisting of quantum electrons and nondegenerate ions. The formation of solitary structures is investigated in two cases: first when the electrons are fully degenerate and second when small temperature effects are taken into account. It is seen that not only rarefactive but coupled rarefactive and compressive solitons are obtained under different temperature conditions.

Shah, H. A.; Qureshi, M. N. S. [Department of Physics, GC University, Lahore 54000 (Pakistan); Tsintsadze, N. [Department of Physics, GC University, Lahore 54000 (Pakistan); Salam Chair, GC University, Lahore 54000 (Pakistan)

2010-03-15T23:59:59.000Z

76

Quantum effects in thermal conduction: Nonequilibrium quantum discord and entanglement  

E-Print Network (OSTI)

We study the process of heat transfer through an entangled pair of two-level system, demonstrating the role of quantum correlations in this nonequilibrium process. While quantum correlations generally degrade with increasing the temperature bias, introducing spatial asymmetry leads to an intricate behavior: Connecting the qubits unequally to the reservoirs one finds that quantum correlations persist and increase with the temperature bias when the system is more weakly linked to the hot reservoir. In the reversed case, linking the system more strongly to the hot bath, the opposite, more natural behavior is observed, with quantum correlations being strongly suppressed upon increasing the temperature bias.

Wu, Lian-Ao

2011-01-01T23:59:59.000Z

77

Quantum effects in thermal conduction: Nonequilibrium quantum discord and entanglement  

E-Print Network (OSTI)

We study the process of heat transfer through an entangled pair of two-level system, demonstrating the role of quantum correlations in this nonequilibrium process. While quantum correlations generally degrade with increasing the temperature bias, introducing spatial asymmetry leads to an intricate behavior: Connecting the qubits unequally to the reservoirs one finds that quantum correlations persist and increase with the temperature bias when the system is more weakly linked to the hot reservoir. In the reversed case, linking the system more strongly to the hot bath, the opposite, more natural behavior is observed, with quantum correlations being strongly suppressed upon increasing the temperature bias.

Lian-Ao Wu; Dvira Segal

2011-05-06T23:59:59.000Z

78

Quantum Statistical Mechanics and Quantum Computation  

E-Print Network (OSTI)

Quantum Statistical Mechanics and Quantum Computation 22-23 March 2012 Room 111, Jadwin Hall, focused meeting to explore the intersection between quantum statistical mechanics and quantum computation, specifically quantum complexity theory. Advances in complexity theory have interesting implications for physics

79

Quantum gravity effects in the Kerr spacetime  

Science Conference Proceedings (OSTI)

We analyze the impact of the leading quantum gravity effects on the properties of black holes with nonzero angular momentum by performing a suitable renormalization group improvement of the classical Kerr metric within quantum Einstein gravity. In particular, we explore the structure of the horizons, the ergosphere, and the static limit surfaces as well as the phase space available for the Penrose process. The positivity properties of the effective vacuum energy-momentum tensor are also discussed and the 'dressing' of the black hole's mass and angular momentum are investigated by computing the corresponding Komar integrals. The pertinent Smarr formula turns out to retain its classical form. As for their thermodynamical properties, a modified first law of black-hole thermodynamics is found to be satisfied by the improved black holes (to second order in the angular momentum); the corresponding Bekenstein-Hawking temperature is not proportional to the surface gravity.

Reuter, M. [Institute of Physics, University of Mainz, Staudingerweg 7, D-55099 Mainz (Germany); Tuiran, E. [Departamento de Fisica, Universidad del Norte, Km 5 via a Puerto Colombia, AA-1569 Barranquilla (Colombia)

2011-02-15T23:59:59.000Z

80

Quantum radiation reaction effects in multiphoton Compton scattering  

E-Print Network (OSTI)

Radiation reaction effects in the interaction of an electron and a strong laser field are investigated in the realm of quantum electrodynamics. We identify quantum radiation reaction with the multiple photon recoils experienced by the laser-driven electron due to consecutive incoherent photon emissions. After determining a quantum radiation dominated regime, we demonstrate how in this regime quantum signatures of radiation reaction strongly affect multiphoton Compton scattering spectra and that they could be measurable in principle with presently available laser technology.

A. Di Piazza; K. Z. Hatsagortsyan; C. H. Keitel

2010-07-28T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Quantum Chevalley groups  

E-Print Network (OSTI)

The goal of this paper is to construct quantum analogues of Chevalley groups inside completions of quantum groups or, more precisely, inside completions of Hall algebras of finitary categories.

Berenstein, Arkady

2012-01-01T23:59:59.000Z

82

Quantum Dynamical Effects in Thermally-Activated Dislocation Glide  

Science Conference Proceedings (OSTI)

We show here that this discrepancy arises from quantum effects in atomic motion (zero-point motion and tunneling) so far neglected in atomistic calculations...

83

Entangling photons via the quantum Zeno effect  

E-Print Network (OSTI)

The quantum Zeno effect describes the inhibition of quantum evolution by frequent measurements. Here, we propose a scheme for entangling two given photons based on this effect. We consider a linear-optics set-up with an absorber medium whose two-photon absorption rate $\\xi_{2\\gamma}$ exceeds the one-photon loss rate $\\xi_{1\\gamma}$. In order to reach an error probability $P_{\\rm error}$, we need $\\xi_{1\\gamma}/\\xi_{2\\gamma}based on coherent excitations of many atoms and exploits the fact that $\\xi_{2\\gamma}$ scales with the number of excitations but $\\xi_{1\\gamma}$ does not. The third mechanism envisages three-level systems where the middle level is meta-stable ($\\Lambda$-system). In this case, $\\xi_{1\\gamma}$ is more strongly reduced than $\\xi_{2\\gamma}$ and thus it should be possible to achieve $\\xi_{2\\gamma}/\\xi_{1\\gamma}\\gg1$. In conclusion, although our scheme poses challenges regarding the density of active atoms/molecules in the absorber medium, their coupling constants and the detuning, etc., we find that a two-photon gate with an error probability $P_{\\rm error}$ below 25% might be feasible using present-day technology.

Nicolai ten Brinke; Andreas Osterloh; Ralf Schtzhold

2012-12-06T23:59:59.000Z

84

Guiding effect of quantum wells in semiconductor lasers  

Science Conference Proceedings (OSTI)

The guiding effect of InGaAs quantum wells in GaAs- and InP-based semiconductor lasers has been studied theoretically and experimentally. The results demonstrate that such waveguides can be effectively used in laser structures with a large refractive index difference between the quantum well material and semiconductor matrix and a large number of quantum wells (e.g. in InP-based structures). (semiconductor lasers. physics and technology)

Aleshkin, V Ya; Dikareva, Natalia V; Dubinov, A A; Zvonkov, B N; Karzanova, Maria V; Kudryavtsev, K E; Nekorkin, S M; Yablonskii, A N

2013-05-31T23:59:59.000Z

85

Knock-On of delta-electrons in Hall A Electron Arm. Effect of the Aerogel Cerenkov.  

E-Print Network (OSTI)

In this note we study the production amount of delta-electrons due to pion knock-on in the different detectors of the Hall A electron High Resolution Spectrometer (HRS). We detail the computation method and the inputs used. The main result is that the aerogel Cerenkov counter provides almost 40 % of the total production of delta-electrons.

Alexandre Deur

1998-01-01T23:59:59.000Z

86

Traditional Residence Halls Residential Colleges  

E-Print Network (OSTI)

,885 Annie Boyd Hall 2-student, suite bath $3,365 2-student, private bath $3,365 Beauregard Hall 2-student

Harms, Kyle E.

87

The effective field theory treatment of quantum gravity  

SciTech Connect

This is a pedagogical introduction to the treatment of quantum general relativity as an effective field theory. It starts with an overview of the methods of effective field theory and includes an explicit example. Quantum general relativity matches this framework and I discuss gravitational examples as well as the limits of the effective field theory. I also discuss the insights from effective field theory on the gravitational effects on running couplings in the perturbative regime.

Donoghue, John F. [Department of Physics, University of Massachusetts, Amherst, MA 01003 (United States)

2012-09-24T23:59:59.000Z

88

Quantum Field Theory Is Not Merely Quantum Mechanics Applied to Low Energy Effective Degrees of Freedom  

E-Print Network (OSTI)

It is commonly assumed that quantum field theory arises by applying ordinary quantum mechanics to the low energy effective degrees of freedom of a more fundamental theory defined at ultra-high-energy/short-wavelength scales. We shall argue here that, even for free quantum fields, there are holistic aspects of quantum field theory that cannot be properly understood in this manner. Specifically, the ``subtractions'' needed to define nonlinear polynomial functions of a free quantum field in curved spacetime are quite simple and natural from the quantum field theoretic point of view, but are at best extremely ad hoc and unnatural if viewed as independent renormalizations of individual modes of the field. We illustrate this point by contrasting the analysis of the Casimir effect, the renormalization of the stress-energy tensor in time-dependent spacetimes, and anomalies from the point of quantum field theory and from the point of view of quantum mechanics applied to the independent low energy modes of the field. Some implications for the cosmological constant problem are discussed.

Stefan Hollands; Robert M. Wald

2004-05-16T23:59:59.000Z

89

Clean Cities: Trev Hall  

NLE Websites -- All DOE Office Websites (Extended Search)

Trev Hall Trev Hall Clean Cities Regional Manager Trev Hall is the point of contact for Clean Cities' coalitions in Alabama, Florida, Georgia, Mississippi, North Carolina, South Carolina, and Tennessee. His responsibilities include facilitating the efforts of the Clean Cities coalitions to increase the use of alternative fuels and vehicles through the development of public-private partnerships. Along with traditional project management duties, Hall facilitates technology deployment strategies, evaluates proper alternative fuel technologies, determines resource availability, provides technical assistance, contributes areas of expertise, and supports transportation market transformation activities. Hall started with the U.S. Department of Energy as a project manager in the Weatherization Assistance Program in 2009. He has a Bachelor of Science in industrial engineering and a master's degree in business administration from West Virginia University. Hall brings experience working as a process-improvement engineer, co-founding start-ups, and leading small-growth companies. Hall has served as an adjunct professor at West Virginia University teaching entrepreneurship/business planning and has a passion for training, technology, marketing, and outreach.

90

WORKFORCE DIVERSITY TOWN HALL  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

WORKFORCE DIVERSITY TOWN HALL WORKFORCE DIVERSITY TOWN HALL DECEMBER 6, 2011 1:00-2:00 PM FORRESTAL MAIN AUDITORIUM (BROADCAST TO ALL SITES) F O C U S M I S S I O N L E A R N I N G C O N T I N U A L DIVERSITY AND INCLUSION A C C O U N T A B I L I T Y WORKFORCE DIVERSITY TOWN HALL "When any of our citizens are unable to fulfill their potential due to the factors that have nothing to do with their talent, character, or work ethic, then I believe there's a role for government to play."

91

Quantum size effects in classical hadrodynamics  

SciTech Connect

The author discusses future directions in the development of classical hydrodynamics for extended nucleons, corresponding to nucleons of finite size interacting with massive meson fields. This new theory provides a natural covariant microscopic approach to relativistic nucleus-nucleus collisions that includes automatically spacetime nonlocality and retardation, nonequilibrium phenomena, interactions among all nucleons, and particle production. The present version of the theory includes only the neutral scalar ({sigma}) and neutral vector ({omega}) meson fields. In the future, additional isovector pseudoscalar ({pi}{sup +}, {pi}{sup {minus}}, {pi}{sup 0}), isovector vector ({rho}{sup +}, {rho}{sup {minus}}, {rho}{sup 0}), and neutral pseudoscalar ({eta}) meson fields should be incorporated. Quantum size effects should be included in the equations of motion by use of the spreading function of Moniz and Sharp, which generates an effective nucleon mass density smeared out over a Compton wavelength. However, unlike the situation in electrodynamics, the Compton wavelength of the nucleon is small compared to its radius, so that effects due to the intrinsic size of the nucleon dominate.

Nix, J.R.

1994-03-01T23:59:59.000Z

92

Hall Effect Measurements Comments  

Science Conference Proceedings (OSTI)

... you in advance. Ma`in Bataineh, Institution: Jordan University of Science & Technology, mainbataineh@yahoo.com. I am ...

2012-06-04T23:59:59.000Z

93

The Hall Effect  

Science Conference Proceedings (OSTI)

... definitions of carrier density n and mobility (third ... magnetic force direction on an electron is then ... 1, the carriers are predominately electrons of bulk ...

2011-12-02T23:59:59.000Z

94

Conference Center Lecture Hall  

NLE Websites -- All DOE Office Websites (Extended Search)

401 Library Take the elevators downstairs to the Gallery. 401 Library Take the elevators downstairs to the Gallery. Conference Center Lecture Hall The Lecture Hall is a fully-equipped site for meetings of up to 540 people. This total includes: 237 seats on the Lecture Hall main level; 161 seats in the Lecture Hall balcony; and 142 seats in the two flexible rooms under the balcony (with interior walls removed). These rooms can also be used for meetings, both individually (32 classroom-style seats) or together (72 classroom-style seats). An additional 80 people can be seated in the nearby seminar room (A1100). Photo of the Conference Center's Lecture Hall Conference Center Gallery Seminar Room (A1101) The Seminar Room is located just off the Atrium. Conference Center Lecture Hall Atrium The Conference Center Atrium provides an open, elegant space ideal for registration, informational displays, and social hours. Computers are located just off the Atruim for e-mail access.

95

Small effects of low-energy quantum gravity  

E-Print Network (OSTI)

Small effects of quantum gravity on the scale $\\sim 10^{-3} eV$ and their cosmological consequences are discussed and compared with observations of supernovae 1a, gamma-ray bursts and galaxies.

Ivanov, Michael A

2007-01-01T23:59:59.000Z

96

Entangling photons via the double quantum Zeno effect  

E-Print Network (OSTI)

We propose a scheme for entangling two photons via the quantum Zeno effect, which describes the inhibition of quantum evolution by frequent measurements and is based on the difference between summing amplitudes and probabilities. Our scheme requires that the one-photon loss rate $\\xi_{1\\gamma}$ and the two-photon absorption rate $\\xi_{2\\gamma}$ in some medium satisfy $\\xi_{1\\gamma}/\\xi_{2\\gamma}=\\ord(P_{\\rm error}^2)$, where $P_{\\rm error}$ is the allowed error probability. Again based on the quantum Zeno effect, as well as coherent excitations, we present a possibility to fulfill this requirement in an otherwise linear optics set-up.

Brinke, Nicolai ten; Schtzhold, Ralf

2011-01-01T23:59:59.000Z

97

Huge Quantum Gravity Effects in the Solar System  

E-Print Network (OSTI)

Normally one thinks of the motion of the planets around the Sun as a highly classical phenomenon, so that one can neglect quantum gravity in the Solar System. However, classical chaos in the planetary motion amplifies quantum uncertainties so that they become very large, giving huge quantum gravity effects. For example, evidence suggests that Uranus may eventually be ejected from the Solar System, but quantum uncertainties would make the direction at which it leaves almost entirely uncertain, and the time of its exit uncertain by about a billion billion years. For a time a billion billion years from now, there are huge quantum uncertainties whether Uranus will be within the Solar System, within the Galaxy, or even within causal contact of the Galaxy.

Don N. Page

2010-05-17T23:59:59.000Z

98

Spacetime effects on satellite-based quantum communications  

E-Print Network (OSTI)

We investigate the effects of space-time curvature on space-based quantum communication protocols. We analyze tasks that require either the exchange of single photons in a certain entanglement distribution protocol or beams of light in a continuous-variable quantum key distribution scheme. We find that gravity affects the propagation of photons, therefore acting as a noisy channel for the transmission of information. The effects can be measured with current technology.

Bruschi, David Edward; Fuentes, Ivette; Jennewein, Thomas; Razavi, Mohsen

2013-01-01T23:59:59.000Z

99

Spacetime effects on satellite-based quantum communications  

E-Print Network (OSTI)

We investigate the effects of space-time curvature on space-based quantum communication protocols. We analyze tasks that require either the exchange of single photons in a certain entanglement distribution protocol or beams of light in a continuous-variable quantum key distribution scheme. We find that gravity affects the propagation of photons, therefore acting as a noisy channel for the transmission of information. The effects can be measured with current technology.

David Edward Bruschi; Tim Ralph; Ivette Fuentes; Thomas Jennewein; Mohsen Razavi

2013-09-12T23:59:59.000Z

100

Effect of localization in quantum wells and quantum wires on heavy-light hole mixing and acceptor binding energy  

Science Conference Proceedings (OSTI)

The variational method taking into account the complex valence band structure is used to study the effect of localization in quantum wells and quantum wires on the acceptor binding energy. Trial functions that make possible tracing of the transition from the bulk material to narrow quantum wells and quantum wires of small radius are constructed. The possibility of the appearance of an unsteadily varying dependence of the acceptor binding energy on the characteristic dimension of the system is shown.

Semina, M. A., E-mail: msemina@gmail.com; Suris, R. A. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation)

2011-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Effective quantum dynamics of interacting systems with inhomogeneous coupling  

SciTech Connect

We study the quantum dynamics of a single mode (particle) interacting inhomogeneously with a large number of particles and introduce an effective approach to find the accessible Hilbert space, where the dynamics takes place. Two relevant examples are given: the inhomogeneous Tavis-Cummings model (e.g., N atomic qubits coupled to a single cavity mode, or to a motional mode in trapped ions) and the inhomogeneous coupling of an electron spin to N nuclear spins in a quantum dot.

Lopez, C. E.; Retamal, J. C. [Departamento de Fisica, Universidad de Santiago de Chile, Casilla 307 Correo 2, Santiago (Chile); Christ, H. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany); Solano, E. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany); Physics Department, ASC, and CeNS, Ludwig-Maximilians-Universitaet, Theresienstrasse 37, 80333 Munich (Germany); Departamento de Ciencias, Seccion Fisica, Pontificia Universidad Catolica del Peru, Apartado 1761, Lima (Peru)

2007-03-15T23:59:59.000Z

102

Energy spectrum, dissipation, and spatial structures in reduced Hall magnetohydrodynamic  

SciTech Connect

We analyze the effect of the Hall term in the magnetohydrodynamic turbulence under a strong externally supported magnetic field, seeing how this changes the energy cascade, the characteristic scales of the flow, and the dynamics of global magnitudes, with particular interest in the dissipation. Numerical simulations of freely evolving three-dimensional reduced magnetohydrodynamics are performed, for different values of the Hall parameter (the ratio of the ion skin depth to the macroscopic scale of the turbulence) controlling the impact of the Hall term. The Hall effect modifies the transfer of energy across scales, slowing down the transfer of energy from the large scales up to the Hall scale (ion skin depth) and carrying faster the energy from the Hall scale to smaller scales. The final outcome is an effective shift of the dissipation scale to larger scales but also a development of smaller scales. Current sheets (fundamental structures for energy dissipation) are affected in two ways by increasing the Hall effect, with a widening but at the same time generating an internal structure within them. In the case where the Hall term is sufficiently intense, the current sheet is fully delocalized. The effect appears to reduce impulsive effects in the flow, making it less intermittent.

Martin, L. N.; Dmitruk, P. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Gomez, D. O. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Instituto de Astronomia y Fisica del Espacio, CONICET, Buenos Aires (Argentina)

2012-05-15T23:59:59.000Z

103

Hall conductivity dominated by fluctuations near the superconducting transition in disordered thin films  

E-Print Network (OSTI)

We have studied the Hall effect in superconducting tantalum nitride films. We find a large contribution to the Hall conductivity near the superconducting transition, which we can track to temperatures well above T[subscript ...

Breznay, Nicholas P.

104

Quantum Electrodynamical Effects in Dusty Plasmas  

E-Print Network (OSTI)

A new nonlinear electromagnetic wave mode in a magnetized dusty plasma is predicted. Its existence depends on the interaction of an intense circularly polarized electromagnetic wave with a dusty plasma, where quantum electrodynamical photon-photon scattering is taken into account. Specifically, we consider a dusty electron-positron-ion plasma, and show that the propagation of the new mode is admitted. It could be of significance for the physics of supernova remnants and in neutron star formation.

M. Marklund; L. Stenflo; P. K. Shukla; G. Brodin

2005-03-17T23:59:59.000Z

105

Quantum effects in unimolecular reaction dynamics  

SciTech Connect

This work is primarily concerned with the development of models for the quantum dynamics of unimolecular isomerization and photodissociation reactions. We apply the rigorous quantum methodology of a Discrete Variable Representation (DVR) with Absorbing Boundary Conditions (ABC) to these models in an attempt to explain some very surprising results from a series of experiments on vibrationally excited ketene. Within the framework of these models, we are able to identify the experimental signatures of tunneling and dynamical resonances in the energy dependence of the rate of ketene isomerization. Additionally, we investigate the step-like features in the energy dependence of the rate of dissociation of triplet ketene to form {sup 3}B{sub 1} CH{sub 2} + {sup 1}{sigma}{sup +} CO that have been observed experimentally. These calculations provide a link between ab initio calculations of the potential energy surfaces and the experimentally observed dynamics on these surfaces. Additionally, we develop an approximate model for the partitioning of energy in the products of photodissociation reactions of large molecules with appreciable barriers to recombination. In simple bond cleavage reactions like CH{sub 3}COCl {yields} CH{sub 3}CO + Cl, the model does considerably better than other impulsive and statistical models in predicting the energy distribution in the products. We also investigate ways of correcting classical mechanics to include the important quantum mechanical aspects of zero-point energy. The method we investigate is found to introduce a number of undesirable dynamical artifacts including a reduction in the above-threshold rates for simple reactions, and a strong mixing of the chaotic and regular energy domains for some model problems. We conclude by discussing some of the directions for future research in the field of theoretical chemical dynamics.

Gezelter, J.D.

1995-12-01T23:59:59.000Z

106

Entangling photons via the double quantum Zeno effect  

E-Print Network (OSTI)

We propose a scheme for entangling two photons via the quantum Zeno effect, which describes the inhibition of quantum evolution by frequent measurements and is based on the difference between summing amplitudes and probabilities. For a given error probability $P_{\\rm error}$, our scheme requires that the one-photon loss rate $\\xi_{1\\gamma}$ and the two-photon absorption rate $\\xi_{2\\gamma}$ in some medium satisfy $\\xi_{1\\gamma}/\\xi_{2\\gamma}=2P_{\\rm error}^2/\\pi^2$, which is significantly improved in comparison to previous approaches. Again based on the quantum Zeno effect, as well as coherent excitations, we present a possibility to fulfill this requirement in an otherwise linear optics set-up.

Nicolai ten Brinke; Andreas Osterloh; Ralf Schtzhold

2011-03-15T23:59:59.000Z

107

Kinetic Isotope Effects from Hybrid Classical and Quantum  

E-Print Network (OSTI)

-order perturbation (KP2) is sufficiently accurate for chemical applications.7 We describe an automated, numerical in chemical applications to determine KIEs for chemical reactions, and because of its fast convergenceCHAPTER 5 Kinetic Isotope Effects from Hybrid Classical and Quantum Path Integral Computations

Minnesota, University of

108

Cerenkov's Effect and Neutrino Oscillations in Loop Quantum Gravity  

E-Print Network (OSTI)

Bounds on the scale parameter {\\cal L} arising in loop quantum gravity theory are derived in the framework of Cerenkov's effect and neutrino oscillations. Assuming that {\\cal L} is an universal constant, we infer {\\cal L}> 10^{-18}eV^{-1}, a bound compatible with ones inferred in different physical context.

G. Lambiase

2003-01-16T23:59:59.000Z

109

Effective cavity pumping from weakly coupled quantum dots  

E-Print Network (OSTI)

We derive the effective cavity pumping and decay rates for the master equation of a quantum dot-microcavity system in presence of $N$ weakly coupled dots. We show that the in-flow of photons is not linked to the out-flow by thermal equilibrium relationships.

del Valle, E

2010-01-01T23:59:59.000Z

110

Edge Dynamics in a Quantum Spin Hall State: Effects from Rashba Spin-Orbit Interaction Anders Strom,1  

E-Print Network (OSTI)

412 96 Gothenburg, Sweden 2 Andronikashvili Institute of Physics, Tamarashvili 6, 0177 Tbilisi, Georgia 3 Ilia State University, Cholokashvili Avenue 3-5, 0162 Tbilisi, Georgia (Received 16 April 2010

Johannesson, Henrik

111

Dark Matter and Dark Energy as Effects of Quantum Gravity  

E-Print Network (OSTI)

I present a theory of quantum gravity based on the principle of gravitational energy fluctuations. Gravitational energy fluctuations -- gravitons -- are responsible for elastic scattering of subatomic particles. Such scattering corresponds to complimentary force -- graviton scattering force -- arising in gravitational interaction in addition to Newtonian gravity. The strength of the graviton scattering force is proportional to the graviton scattering probability. Unlike Newtonian gravity the graviton scattering force follows the 1/r law and dominates the former on cosmological scale in the limit of low orbital accelerations. Similarly to Modified Newtonian Dynamics the quantum gravity accounts for variations in observed M/L ratios of diverse stellar systems ranging from dwarf spheroid galaxies to X-ray galaxy clusters without requiring an invisible matter (which is still required by MOND in X-Ray cluster cores). Unlike MOND the presented theory neither violates cornerstone Newton Laws nor suffers from the ambiguity of acceleration frames while enjoying vast experimental evidence usually cited in favor of MOND. To ascertain the validity of the presented theory I have examined the predictions of quantum gravity for dwarf spheroid, ordinary and giant elliptic galaxies, and X-ray clusters. In all cases quantum gravity yields M/L ratios and scaling relations consistent with observations. Quantum gravity accounts for the tilt of the Fundamental Plane of elliptical galaxies erasing the differences in M/L vs. luminosity relations for faint and bright ellipticals, which cannot be easily explained by CDM model. Lastly, by analyzing the behavior of the gravitational energy fluctuations in the limit of high matter density expected in the early Universe I show that primordial inflation and dark energy (i.e. non-zero cosmological constant) arise as natural effects of quantum gravity in the expanding Universe.

Max I. Fomitchev

2010-09-07T23:59:59.000Z

112

Transforming quantum operations: quantum supermaps  

E-Print Network (OSTI)

We introduce the concept of quantum supermap, describing the most general transformation that maps an input quantum operation into an output quantum operation. Since quantum operations include as special cases quantum states, effects, and measurements, quantum supermaps describe all possible transformations between elementary quantum objects (quantum systems as well as quantum devices). After giving the axiomatic definition of supermap, we prove a realization theorem, which shows that any supermap can be physically implemented as a simple quantum circuit. Applications to quantum programming, cloning, discrimination, estimation, information-disturbance trade-off, and tomography of channels are outlined.

G. Chiribella; G. M. D'Ariano; P. Perinotti

2008-04-01T23:59:59.000Z

113

under construction Bing Concert Hall,  

E-Print Network (OSTI)

Cobb Track & Angell Field Varian Physics Sequoia Hall William R. Hewlett Teaching Center Herrin Hall Psychiatry America Lou Henry Hoover House Vaden Health Center Bing Nursery School Stanford Community Park Path Bike route to M enlo Park Bike Bridge PALMDR LOW ELL AV TENNYSON AV ARBORETUM RD COLERIDGE AV

Kay, Mark A.

114

Bing Concert Hall, Under Construction  

E-Print Network (OSTI)

Varian Physics Sequoia Hall William R. Hewlett Teaching Center Herrin Hall Gilbert Biological Sciences SciencesObservatory Lou Henry Hoover House Vaden Health Center Bing Nursery School Stanford Community Branner Dining Dining Beefeaters Avanti Parking Struct. 7 William H. Neukom Building Avery Plaza DAPER

Prinz, Friedrich B.

115

Bing Concert Hall, Under Construction  

E-Print Network (OSTI)

Varian Physics Sequoia Hall William R. Hewlett Teaching Center Herrin Hall Gilbert Biological Sciences Sciences Golf Clubhouse Observatory Lou Henry Hoover House Vaden Health Center Bing Nursery School Stanford William H. Neukom Building Avery Plaza DAPER Corp. Yard Lorry Lokey Stem Cell Research Building (SIM1

Prinz, Friedrich B.

116

Bing Concert Hall, Under Construction  

E-Print Network (OSTI)

Hall William R. Hewlett Teaching Center Herrin Hall Gilbert Biological Sciences Gates Computer Science Observatory Lou Henry Hoover House Vaden Health Center Bing Nursery School Stanford Community Recreation Avanti Parking Struct. 7 William H. Neukom Building Avery Plaza DAPER Corp. Yard Lorry Lokey Stem Cell

Gross, James J.

117

Bing Concert Hall, Under Construction  

E-Print Network (OSTI)

Varian Physics Sequoia Hall William R. Hewlett Teaching Center Herrin Hall Gilbert Biological Sciences Golf Clubhouse Observatory Lou Henry Hoover House Vaden Health Center Bing Nursery School Stanford Admin. HFD Branner Dining Dining Beefeaters Avanti Parking Struct. 7 William H. Neukom Building Avery

Prinz, Friedrich B.

118

Bing Concert Hall, under construction  

E-Print Network (OSTI)

Tennis Stadium 3341 Varian Physics Sequoia Hall William R. Hewlett Teaching Center Herrin Hall Gilbert Clinic Vaden Health Center 127 128 129 13 20 238 235 234 228 141143 144 142 137 135 11 11 117 118 120 121 Gunn (SIEPR) 233236 232 13 136 138 140 H M A Center for Nanoscale Science and Engineering Jen

Gross, James J.

119

Bing Concert Hall, Under Construction  

E-Print Network (OSTI)

340 315327 333341 Varian Physics Sequoia Hall William R. Hewlett Teaching Center Herrin Hall Gilbert Sciences Golf Clubhouse Observatory Lou Henry Hoover House Vaden Health Center Bing Nursery School Stanford Avanti Parking Struct. 7 William H. Neukom Building Avery Plaza DAPER Corp. Yard Lorry Lokey Stem Cell

Prinz, Friedrich B.

120

Divacancy-hydrogen complexes in dislocation-free high-purity germanium. [Annealing, Hall effect, steady-state concentration energy dependence  

DOE Green Energy (OSTI)

A defect center with a single acceptor level at E/sub v/ + 0.08 eV appears in H/sub 2/-grown dislocation-free high-purity germanium. Its concentration changes reversibly upon annealing up to 650 K. By means of Hall-effect and conductivity measurements over a large temperature range the temperature dependence of the steady-state concentration between 450 and 720 K as well as the transients following changes in temperature were determined. The observed acceptor level is attributed to the divacancy-hydrogen complex V/sub 2/H. The complex reacts with hydrogen, dissolved in the Ge lattice or stored in traps, according to V/sub 2/H + H reversible V/sub 2/H/sub 2/. An energy level associated with the divacancy-dihydrogen complex was not observed. These results are in good agreement with the idea that hydrogen in germanium forms a ''very deep donor'' (i.e., the energy level lies inside the valence band).

Haller, E.E.; Hubbard, G.S.; Hansen, W.L.; Seeger, A.

1976-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Quantum instanton evaluation of the kinetic isotope effects  

DOE Green Energy (OSTI)

A general quantum-mechanical method for computing kinetic isotope effects is presented. The method is based on the quantum instanton approximation for the rate constant and on the path integral Metropolis Monte-Carlo evaluation of the Boltzmann operator matrix elements. It computes the kinetic isotope effect directly, using a thermodynamic integration with respect to the mass of the isotope, thus avoiding the more computationally expensive process of computing the individual rate constants. The method is more accurate than variational transition-state theories or the semiclassical instanton method since it does not assume a single reaction path and does not use a semiclassical approximation of the Boltzmann operator. While the general Monte-Carlo implementation makes the method accessible to systems with a large number of atoms, we present numerical results for the Eckart barrier and for the collinear and full three-dimensional isotope variants of the hydrogen exchange reaction H+H{sub 2} {yields} H{sub 2}+H. In all seven test cases, for temperatures between 250 K and 600 K, the error of the quantum instanton approximation for the kinetic isotope effects is less than {approx}10%.

Vanicek, Jiri; Miller, William H.; Castillo, Jesus F.; Aoiz, F.Javier

2005-04-19T23:59:59.000Z

122

Effect of phonon confinement on the thermoelectric figure of merit of quantum wells  

E-Print Network (OSTI)

Effect of phonon confinement on the thermoelectric figure of merit of quantum wells Alexander in quantum wells and superlattices due to two-dimensional carrier confinement. We predict that the figure of merit can increase even further in quantum well structures with free-surface or rigid boundaries

123

Nontrivial quantum effects in biology: A skeptical physicists' view  

E-Print Network (OSTI)

Invited contribution to "Quantum Aspects of Life", D. Abbott Ed. (World Scientific, Singapore, 2007).

H. M. Wiseman; J. Eisert

2007-05-09T23:59:59.000Z

124

Nontrivial quantum effects in biology: A skeptical physicists' view  

E-Print Network (OSTI)

Invited contribution to "Quantum Aspects of Life", D. Abbott Ed. (World Scientific, Singapore, 2007).

Wiseman, H W

2007-01-01T23:59:59.000Z

125

Anomalous particle-production thresholds through systematic and non-systematic quantum-gravity effects  

E-Print Network (OSTI)

A growing number of studies is being devoted to the identification of plausible quantum properties of spacetime which might give rise to observably large effects. The literature on this subject is now relatively large, including studies in string theory, loop quantum gravity and noncommutative geometry. It is useful to divide the various proposals into proposals involving a systematic quantum-gravity effect (an effect that would shift the main/average prediction for a given observable quantity) and proposals involving a non-systematic quantum-gravity effect (an effect that would introduce new fundamental uncertanties in some observable quantity). The case of quantum-gravity-induced particle-production-threshold anomalies, a much studied example of potentially observable quantum-gravity effect, is here used as an example to illustrate the differences to be expected between systematic and non-systematic effects.

Giovanni Amelino-Camelia; Y. Jack NG; Hendrik Van Dam

2002-04-24T23:59:59.000Z

126

Cosmopolitanism - Conversation with Stuart Hall  

E-Print Network (OSTI)

Conversation between Stuart Hall and Pnina Werbner on the theme of Cosmopolitanism (to be shown at the Association of Social Anthropologists Silver Jubilee conference in 2006), in March 2006...

Hall, Stuart

2006-09-27T23:59:59.000Z

127

Polaron effect-dependent third-order optical susceptibility in a ZnS/CdSe quantum dot quantum well  

Science Conference Proceedings (OSTI)

The effect of the electron-phonon interaction on the third-harmonic is investigated theoretically for electrons confined in a core-shell quantum dot. The interactions of electrons with different phonon modes in the core-shell system, including the confined ... Keywords: 42.65.An, 71.38.-k, 78.67.Hc, Core-shell quantum dot, Nonlinear optical susceptibility, Polarons

Zhihong Chen; Duanzheng Yao; Xi Zhang; Tianhong Fang

2008-12-01T23:59:59.000Z

128

On Quantum Coherence Effects in Photo and Solar Cells  

E-Print Network (OSTI)

We show that quantum coherence can increase the quantum efficiency of various thermodynamic systems. For example, we can enhance the quantum efficiency for a quantum dot photocell, a laser based solar cell and the photo-Carnot quantum heat engine. Our results are fully consistent with the laws of thermodynamics contrary to comments found in the paper of A.P. Kirk, Phys. Rev. Lett. 106, 048703 (2011).

Kimberly Chapin; Konstantin Dorfman; Anatoly Svidzinsky; Marlan Scully

2010-12-23T23:59:59.000Z

129

Effects of asymmetry on electron spin dynamics in gallium arsenide quantum wells.  

E-Print Network (OSTI)

??This work presents optical studies of electron spin dynamics in gallium arsenide (GaAs) quantum wells, focusing on the effect of inversion asymmetric confinement potentials on (more)

Eldridge, Peter Stephen

2009-01-01T23:59:59.000Z

130

Cellular Effect of High Doses of Silica-Coated Quantum Dot ...  

Cellular Effect of High Doses of Silica-Coated Quantum Dot Profiled with High Throughput Gene Expression Analysis and High Content Cellomics ...

131

Quantum resonance effects in exchange, photodissociation, and recombination reactions  

DOE Green Energy (OSTI)

This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This project studied quantum resonance effects on chemical reactions. The authors accurate reactive scattering calculations showed that quantum resonance phenomena dominate most chemical reactions and are essential to any real understanding of reactivity. It was found that, as long-lived metastable states of the colliding system, resonances can decay to reactants, products, or a mixture of both. Only the latter contribute to reaction. Conditions under which resonances can be neglected or treated statistically were studied. Important implications about the mechanism of recombination reactions were discovered, and some remarkable effects of geometric phases on the symmetries and energies of resonances were also discovered. Calculations were completed for the reaction H + O{sub 2} {yields} OH + O, which is the rate limiting step in the combustion of all hydrocarbons and the single most important reaction in all of combustion chemistry.

Pack, R.; Kendrick, B.; Kress, J.; Walker, R. [Los Alamos National Lab., NM (United States); Hayes, E. [Ohio State Univ., Columbus, OH (United States); Lagana, A. [Univ. of Perugia (Italy); Parker, G. [Univ. of Oklahoma, Norman, OK (United States); Butcher, E. [Auburn Univ., AL (United States)

1996-04-01T23:59:59.000Z

132

488 Brazilian Journal of Physics, vol. 36, no. 2A, June, 2006 Spin Valve Effect and Hall Resistance in a Wide Parabolic Well  

E-Print Network (OSTI)

in a Wide Parabolic Well C. A. Duarte, G. M. Gusev, A. A. Quivy, and T. E. Lamas Instituto de F´isica da observation of the Hall slope change in wide AlcGa1-cAs parabolic wells in the presence of a quasi on the electron density; it is observed only in parabolic wells, which are almost completely filled by electrons

Gusev, Guennady

133

NMR quantum simulation of localization effects induced by decoherence  

E-Print Network (OSTI)

The loss of coherence in quantum mechanical superposition states limits the time for which quantum information remains useful. Similarly, it limits the distance over which quantum information can be transmitted, resembling Anderson localization, where disorder causes quantum mechanical states to become localized. Here, we investigate in a nuclear spin-based quantum simulator, the localization of the size of spin clusters that are generated by a Hamiltonian driving the transmission of information, while a variable-strength perturbation counteracts the spreading. We find that the system reaches a dynamic equilibrium size, which decreases with the square of the perturbation strength.

Gonzalo A. Alvarez; Dieter Suter

2010-04-28T23:59:59.000Z

134

Group velocity of extraordinary waves in superdense magnetized quantum plasma with spin-1/2 effects  

Science Conference Proceedings (OSTI)

Based on the one component plasma model, a new dispersion relation and group velocity of elliptically polarized extraordinary electromagnetic waves in a superdense quantum magnetoplasma are derived. The group velocity of the extraordinary wave is modified due to the quantum forces and magnetization effects within a certain range of wave numbers. It means that the quantum spin-1/2 effects can reduce the transport of energy in such quantum plasma systems. Our work should be of relevance for the dense astrophysical environments and the condensed matter physics.

Li Chunhua; Ren Haijun; Yang Weihong [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Wu Zhengwei [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

2012-12-15T23:59:59.000Z

135

Town Hall meeting | OpenEI Community  

Open Energy Info (EERE)

Town Hall meeting Town Hall meeting Home Graham7781's picture Submitted by Graham7781(1992) Super contributor 16 November, 2012 - 11:23 LEDS the focus of Monday's 10 a.m. Town Hall Meeting LEDS Town Hall meeting What: OpenEI's town hall meeting is a half-hour open forum for discussions on energy topics with NREL's OpenEI team. Find out how your fellow researchers, students, teachers and energy professionals are using energy data, maps and tools. Graham7781's picture Submitted by Graham7781(1992) Super contributor 19 September, 2012 - 13:40 Town Hall Meeting October 1st, 2012 OpenEI Town Hall meeting What: OpenEI's town hall meeting is a half-hour open forum for discussions on energy topics with NREL's OpenEI team. Find out how your fellow researchers, students, teachers and energy professionals are using energy

136

Hall Ammendment Policy | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Hall Ammendment Policy Hall Ammendment Policy Joint statement providing interim policy on processing proposals for leasing DOE real property using the authority in 42 U.S.C. 7256,...

137

City Hall plazas : they're different  

E-Print Network (OSTI)

This essay explores the form, goals, and ideals behind city hall plazas by asking the questions: What is the difference between a city hall plaza and any other urban plaza? What are the uses intended by the city in the ...

Hall, Kristen E. (Kristen Elizabeth)

2008-01-01T23:59:59.000Z

138

Experiment Hall & Beamline | Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

Experiment Hall & Beamlines The ratchet-shaped radiation-shielding wall between the APS storage ring and the experiment hall serves as a line of demarcation. Thirty-five "sectors"...

139

Directions to Jadwin Hall/PCTS from Lot 21 and Scully Hall You can find the interactive campus map from  

E-Print Network (OSTI)

Directions to Jadwin Hall/PCTS from Lot 21 and Scully Hall You can find the interactive campus map Washington Rd. Jadwin Hall/PCTS is directly across the street from this pass. Enter into the McDonnell Hall

140

Quantum dissipative effects in graphene-like mirrors  

E-Print Network (OSTI)

We study quantum dissipative effects due to the accelerated motion of a single, imperfect, zero-width mirror. It is assumed that the microscopic degrees of freedom on the mirror are confined to it, like in plasma or graphene sheets. Therefore, the mirror is described by a vacuum polarization tensor $\\Pi_{\\alpha\\beta}$ concentrated on a time-dependent surface. Under certain assumptions about the microscopic model for the mirror, we obtain a rather general expression for the Euclidean effective action, a functional of the time-dependent mirror's position, in terms of two invariants that characterize the tensor $\\Pi_{\\alpha\\beta}$. The final result can be written in terms of the TE and TM reflection coefficients of the mirror, with qualitatively different contributions coming from them. We apply that general expression to derive the imaginary part of the `in-out' effective action, which measures dissipative effects induced by the mirror's motion, in different models, in particular for an accelerated graphene sheet.

C. D. Fosco; F. C. Lombardo; F. D. Mazzitelli; M. L. Remaggi

2013-07-02T23:59:59.000Z

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141

Bing Concert Hall, Under Construction  

E-Print Network (OSTI)

Tennis Stadium 340 315327 333341 Varian Physics Sequoia Hall William R. Hewlett Teaching Center Herrin for Advanced Study in the Behavioral Sciences Golf Clubhouse Observatory Lou Henry Hoover House Vaden Health Admin. HFD Branner Dining Dining Beefeaters Avanti Parking Struct. 7 William H. Neukom Building Avery

Prinz, Friedrich B.

142

Bing Concert Hall, Under Construction  

E-Print Network (OSTI)

Rehearsal Facility Taube Family Tennis Stadium 3341 Varian Physics Sequoia Hall William R. Hewlett Teaching Beckman Center Ctr. for Clinical Sciences Research (CCSR) Stanford Clinic Vaden Health Center 20 235 234 William H. Neukom Building Avery Plaza Lorry Lokey Stem Cell Research Building (SIM1) Admin. Police Dept

Prinz, Friedrich B.

143

Bing Concert Hall, under construction  

E-Print Network (OSTI)

Stadium 340 315327 333341 Cobb Track & Angell Field Varian Physics Sequoia Hall William R. Hewlett Sciences Golf Clubhouse Observatory Lou Henry Hoover House Vaden Health Center Bing Nursery School Stanford To Foothi llExpressway To Interstate 280 via Pa geMillRd Bike route to M enlo Park Bike Bridge $&(+"0 .-1

144

Bing Concert Hall, Under Construction  

E-Print Network (OSTI)

Tennis Stadium 340 315327 333341 Varian Physics Sequoia Hall William R. Hewlett Teaching Center Herrin Stanford Barn800 780 Psychiatry Vaden Health Center Bing Nursery School Stanford Community Recreation Dining Dining Parking Struct. 7 William H. Neukom Building Avery Plaza DAPER Corp. Yard Lorry Lokey Stem

Quake, Stephen R.

145

Bing Concert Hall, under construction  

E-Print Network (OSTI)

333341 Cobb Track & Angell Field Varian Physics Sequoia Hall William R. Hewlett Teaching Center Herrin Sciences Golf Clubhouse Observatory Lou Henry Hoover House Vaden Health Center Bing Nursery School Stanford AV TEO DR ARBORETUM RD COLERIDGE A W Y KELLOGG AV CASTILLEJA AV M ARIPOSA AV E L DR M IRAM ONTE AV M

Prinz, Friedrich B.

146

Bing Concert Hall, under construction  

E-Print Network (OSTI)

Facility Police Services Fire Station Taube Family Tennis Stadium 33341 Varian Physics Sequoia Hall William of Medicine ve Fairchild Center Beckman Center Stanford Clinic Vaden Health Center 127 128 129 1 132 207 238 140 H M A Center for Nanoscale Science and Engineering Jen-Hsun Huang Engineering SIM1 Lantana

Prinz, Friedrich B.

147

Quantum discord  

NLE Websites -- All DOE Office Websites (Extended Search)

Quantum discord Quantum discord 1663 Los Alamos science and technology magazine Latest Issue:November 2013 All Issues » submit Quantum discord A distinguishing aspect of quantum mechanics discovered at Los Alamos that may be critical to building a quantum computer March 25, 2013 Spinning coins turning into binary numbers Quantum computing Quantum computing can be carried out without the delicate entanglement of qubits previously believed to be necessary Quantum computing, in which quantum bits of information (or qubits) juggle a "superposition" of multiple values simultaneously, offers to unleash tremendous computational power if the qubits can be effectively isolated to prevent decoherence: information describing quantum states dispersing into the environment. But recent research has shown that quantum computing can be carried out

148

Session P: Quantum Effect Materials: InAs Dots - TMS  

Science Conference Proceedings (OSTI)

"Room Temperature Lasing From Excited Stated of InGaAs Quantum Dots:" RICHARD MIRIN, Arthur Gossard, John Bowers, ECE Department, MS100,...

149

The Quantum Effects of Pore Structure on Hydrogen Adsorption...  

NLE Websites -- All DOE Office Websites (Extended Search)

Objectives Neutron characterization of variants of sample of interest * Measurement of quantum states in idealized oriented * carbon adsorbent Demonstrate theoretical origin of...

150

DARK MATTER AND DARK ENERGY AS EFFECTS OF QUANTUM GRAVITY Max I. Fomitchev1  

E-Print Network (OSTI)

DARK MATTER AND DARK ENERGY AS EFFECTS OF QUANTUM GRAVITY Max I. Fomitchev1 Submitted March 12th , 2004 ABSTRACT I present a theory of quantum gravity based on the principle of gravitational energy fluctuations. Gravitational energy fluctuations ­ gravitons ­ are responsible for elastic scattering

Giles, C. Lee

151

The effect of temperature and magnetic field on a quantum rod qubit  

Science Conference Proceedings (OSTI)

The Hamiltonian of a quantum rod (QR) with an ellipsoidal boundary is given after a coordinate transformation, which changes the ellipsoidal boundary into a spherical one. We obtain the eigenenergies and eigenfunctions of the ground and the first excited ... Keywords: Magnetic field, Quantum rod, Qubit, Temperature effect

Yong Sun; Zhao-Hua Ding; Jing-Lin Xiao

2013-02-01T23:59:59.000Z

152

Anthony Kathryn Hall | Open Energy Information  

Open Energy Info (EERE)

Anthony Kathryn Hall Anthony Kathryn Hall Jump to: navigation, search Name Anthony & Kathryn Hall Place United Kingdom Sector Wind energy Product UK-based private wind farm in Highland. References Anthony & Kathryn Hall[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Anthony & Kathryn Hall is a company located in United Kingdom . References ↑ "Anthony & Kathryn Hall" Retrieved from "http://en.openei.org/w/index.php?title=Anthony_Kathryn_Hall&oldid=342207" Categories: Clean Energy Organizations Companies Organizations Stubs What links here Related changes Special pages Printable version Permanent link Browse properties 429 Throttled (bot load) Error 429 Throttled (bot load)

153

Energy-Efficient Residence Hall  

E-Print Network (OSTI)

Recently, there has been an increase in the number of energy efficient buildings in the U.S. We want to encourage this green movement by providing people with a simple and systematic Stairwell Closable vents leading from the floor to the stairwell along with windows in the stairwell leading outside act as a thermal chimney which gets rid of excess heat. approach for green building construction. Our project focuses on creating a guideline for an energy-efficient residence hall. We have looked into energy-efficient and eco-friendly lighting, heating, insulation, and other aspects that integrate into a green building. Our guideline, as a result, will aid colleges in the Worcester community to design and construct green residence halls.

Giselle Chen; Nathaniel Eames; Andrew Holmes; Grant Wong; Advisor David Spanagel (humanities; Arts Department

2009-01-01T23:59:59.000Z

154

Green formula in Hall algebras and cluster algebras  

E-Print Network (OSTI)

The objective of the present paper is to give a survey of recent progress on applications of the approaches of Ringel-Hall type algebras to quantum groups and cluster algebras via various forms of Green's formula. In this paper, three forms of Green's formula are highlighted, (1) the original form of Green's formula \\cite{Green}\\cite{RingelGreen}, (2) the degeneration form of Green's formula \\cite{DXX} and (3) the projective form of Green's formula \\cite{XX2007a} i.e. Green formula with a $\\bbc^{*}$-action.

Xiao, Jie

2008-01-01T23:59:59.000Z

155

Quadratic fermionic interactions yield effective Hamiltonians for adiabatic quantum computing  

E-Print Network (OSTI)

Polynomially-large ground-state energy gaps are rare in many-body quantum systems, but useful for adiabatic quantum computing. We show analytically that the gap is generically polynomially-large for quadratic fermionic Hamiltonians. We then prove that adiabatic quantum computing can realize the ground states of Hamiltonians with certain random interactions, as well as the ground states of one, two, and three-dimensional fermionic interaction lattices, in polynomial time. Finally, we use the Jordan-Wigner transformation and a related transformation for spin-3/2 particles to show that our results can be restated using spin operators in a surprisingly simple manner. A direct consequence is that the one-dimensional cluster state can be found in polynomial time using adiabatic quantum computing.

Michael J. O'Hara; Dianne P. O'Leary

2008-08-13T23:59:59.000Z

156

Hall Magnetohydrodynamics of weakly-ionized plasma  

E-Print Network (OSTI)

We show that the Hall scale in a weakly ionized plasma depends on the fractional ionization of the medium and, Hall MHD description becomes important whenever the ion-neutral collision frequency is comparable to the ion-gyration frequency, or, the ion-neutral collisional mean free path is smaller than the ion gyro-radius. Wave properties of a weakly-ionized plasma also depends on the fractional ionization and plasma Hall parameters, and whistler mode is the most dominant mode in such a medium. Thus Hall MHD description will be important in astrophysical disks, dark molecular clouds, neutron star crusts, and, solar and planetary atmosphere.

B. P. Pandey; Mark Wardle

2006-08-01T23:59:59.000Z

157

Hall viscosity from gauge/gravity duality  

E-Print Network (OSTI)

In (2+1)-dimensional systems with broken parity, there exists yet another transport coefficient, appearing at the same order as the shear viscosity in the hydrodynamic derivative expansion. In condensed matter physics, it is referred to as "Hall viscosity". We consider a simple holographic realization of a (2+1)-dimensional isotropic fluid with broken spatial parity. Using techniques of fluid/gravity correspondence, we uncover that the holographic fluid possesses a nonzero Hall viscosity, whose value only depends on the near-horizon region of the background. We also write down a Kubo's formula for the Hall viscosity. We confirm our results by directly computing the Hall viscosity using the formula.

Omid Saremi; Dam Thanh Son

2011-03-24T23:59:59.000Z

158

The effects of quantum dot coverage in InAs/(In)GaAs nanostructures for long wavelength emission  

Science Conference Proceedings (OSTI)

We present a study on the effects of quantum dot coverage on the properties of InAs dots embedded in GaAs and in metamorphic In0.15Ga0.85As confining layers grown by molecular beam epitaxy on GaAs substrates. We show that redshifted ... Keywords: Long wavelength emission, Molecular beam epitaxy, Quantum dot ripening, Quantum dots

G. Trevisi; L. Seravalli; P. Frigeri; M. Prezioso; J. C. Rimada; E. Gombia; R. Mosca; L. Nasi; C. Bocchi; S. Franchi

2009-03-01T23:59:59.000Z

159

Characteristics of quadratic electro-optic effects and electro-absorption process in CdSe parabolic quantum dots  

Science Conference Proceedings (OSTI)

The nonlinear susceptibilities have been calculated theoretically for CdSe disk-like parabolic quantum dots by using a two-energy-level model in the strong-confinement regime. The confined wave functions and eigenenergies of excitons in parabolic quantum ... Keywords: Electro-optical effects, Excitons, Parabolic quantum dot

Shufei Xie; Guiguang Xiong; Xiaobo Feng; Zhihong Chen

2007-06-01T23:59:59.000Z

160

Diversity and Inclusion Town Hall | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Town Hall Diversity and Inclusion Town Hall August 9, 2012 12:30PM EDT Savannah River Site Diversity and Inclusion Town Hall at Savannah River Site for employees and contractors....

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Secretary Moniz at Town Hall Forum on Departmental Reorganization...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Sites Power Marketing Administration Other Agencies You are here Home Secretary Moniz at Town Hall Forum on Departmental Reorganization Secretary Moniz at Town Hall Forum...

162

Department of Energy Town Hall with Secretary Moniz | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Other Agencies You are here Home Department of Energy Town Hall with Secretary Moniz Department of Energy Town Hall with Secretary Moniz Addthis Speakers Secretary Ernest...

163

OpenEI Community - Town Hall meeting  

Open Energy Info (EERE)

http://en.openei.org/community Town Hall Meeting October 1st, 2012 http://en.openei.org/community Town Hall Meeting October 1st, 2012 http://en.openei.org/community/blog/town-hall-meeting-october-1st-2012  

What: OpenEI's town hall meeting is a half-hour open forum for discussions on energy topics with NREL's OpenEI team. Find out how your fellow researchers, students, teachers and energy professionals are using energy data, maps and tools.hall-meeting-october-1st-2012" target="_blank">read more

164

Scanning Hall Probe Microscopy of Magnetic Vortices inVery Underdoped yttrium-barium-copper-oxide  

Science Conference Proceedings (OSTI)

Since their discovery by Bednorz and Mueller (1986), high-temperature cuprate superconductors have been the subject of intense experimental research and theoretical work. Despite this large-scale effort, agreement on the mechanism of high-T{sub c} has not been reached. Many theories make their strongest predictions for underdoped superconductors with very low superfluid density n{sub s}/m*. For this dissertation I implemented a scanning Hall probe microscope and used it to study magnetic vortices in newly available single crystals of very underdoped YBa{sub 2}Cu{sub 3}O{sub 6+x} (Liang et al. 1998, 2002). These studies have disproved a promising theory of spin-charge separation, measured the apparent vortex size (an upper bound on the penetration depth {lambda}{sub ab}), and revealed an intriguing phenomenon of ''split'' vortices. Scanning Hall probe microscopy is a non-invasive and direct method for magnetic field imaging. It is one of the few techniques capable of submicron spatial resolution coupled with sub-{Phi}{sub 0} (flux quantum) sensitivity, and it operates over a wide temperature range. Chapter 2 introduces the variable temperature scanning microscope and discusses the scanning Hall probe set-up and scanner characterizations. Chapter 3 details my fabrication of submicron GaAs/AlGaAs Hall probes and discusses noise studies for a range of probe sizes, which suggest that sub-100 nm probes could be made without compromising flux sensitivity. The subsequent chapters detail scanning Hall probe (and SQUID) microscopy studies of very underdoped YBa{sub 2}Cu{sub 3}O{sub 6+x} crystals with T{sub c} {le} 15 K. Chapter 4 describes two experimental tests for visons, essential excitations of a spin-charge separation theory proposed by Senthil and Fisher (2000, 2001b). We searched for predicted hc/e vortices (Wynn et al. 2001) and a vortex memory effect (Bonn et al. 2001) with null results, placing upper bounds on the vison energy inconsistent with the theory. Chapter 5 discusses imaging of isolated vortices as a function of T{sub c}. Vortex images were fit with theoretical magnetic field profiles in order to extract the apparent vortex size. The data for the lowest T{sub c}'s (5 and 6.5 K) show some inhomogeneity and suggest that {lambda}{sub ab} might be larger than predicted by the T{sub c} {proportional_to} n{sub s}(0)/m* relation first suggested by results of Uemura et al. (1989) for underdoped cuprates. Finally, Chapter 6 examines observations of apparent ''partial vortices'' in the crystals. My studies of these features indicate that they are likely split pancake vortex stacks. Qualitatively, these split stacks reveal information about pinning and anisotropy in the samples. Collectively these magnetic imaging studies deepen our knowledge of cuprate superconductivity, especially in the important regime of low superfluid density.

Guikema, Janice Wynn; /SLAC, SSRL

2005-12-02T23:59:59.000Z

165

Correlation effects on topological insulator  

E-Print Network (OSTI)

The strong correlation effects on topological insulator are studied in a two-sublattice system with an onsite single-particle energy difference $\\Delta$ between two sublattices. At $\\Delta=0$, increasing the onsite interaction strength $U$ drives the transition from the quantum spin Hall insulating state to the non-topological antiferromagnetic Mott-insulating (AFMI) state. When $\\Delta$ is larger than a certain value, a topologically trivial band insulator or AFMI at small values of $U$ may change into a quantum anomalous Hall state with antiferromagnetic ordering at intermediate values of $U$. Further increasing $U$ drives the system back into the topologically trivial state of AFMI. The corresponding phenomena is observable in the solid state and cold atom systems. We also propose a scheme to realize and detect these effects in cold atom systems.

Xiong-Jun Liu; Yang Liu; Xin Liu

2010-11-23T23:59:59.000Z

166

A new town hall for Norwich, Vermont  

E-Print Network (OSTI)

... the public building is not an abstract symbol, but partakes in daily life, which relates to what is timeless and common. The objective of this thesis was to design a new town hall for Norwich, Vermont. The design ...

Harboe, Peter Thomas McIlvaine

1988-01-01T23:59:59.000Z

167

Building Green in Greensburg: City Hall Building  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

City Hall Building City Hall Building Destroyed in the tornado, City Hall was completed in October 2009 and built to achieve the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED ® ) Platinum designation. The 4,700-square-foot building serves as a symbol of Greensburg's vitality and leadership in becoming a sustainable community where social, environmental, and economic concerns are held in balance. It houses the City's administrative offices and council chambers, and serves as a gathering place for town meetings and municipal court sessions. According to energy analysis modeling results, the new City Hall building is 38% more energy efficient than an ASHRAE-compliant building of the same size and shape. ENERGY EFFICIENCY FEATURES * A well-insulated building envelope with an

168

Clean Cities: Clean Cities Hall of Fame  

NLE Websites -- All DOE Office Websites (Extended Search)

Hall of Fame Hall of Fame U.S. Department of Energy Clean Cities Hall of Fame logo The Clean Cities Hall of Fame recognizes outstanding contributions to the Clean Cities mission of reducing petroleum dependency in U.S. transportation. Inductees are ambassadors for alternative fuels and champions for fuel economy. Their exemplary dedication and leadership are paving the way for a new transportation future. 2013 Inductees 2012 Inductees Photo of Yvonne Anderson Yvonne Anderson Central Oklahoma Clean Cities Photo of Rita Ebert Rita Ebert Greater Long Island Clean Cities Coalition Photo of Richard Battersby Richard Battersby East Bay Clean Cities Photo of Lee Grannis Lee Grannis New Haven Clean Cities 2011 Inductees Photo of Colleen Crowninshield Colleen Crowninshield Tucson Clean Cities Coalition

169

Measurements of Plasma Potential Distribution in Segmented Electrode Hall Thruster  

DOE Green Energy (OSTI)

Use of a segmented electrode placed at the Hall thruster exit can substantially reduce the voltage potential drop in the fringing magnetic field outside the thruster channel. In this paper, we investigate the dependence of this effect on thruster operating conditions and segmented electrode configuration. A fast movable emissive probe is used to measure plasma potential in a 1 kW laboratory Hall thruster with semented electrodes made of a graphite material. Relatively small probe-induced perturbations of the thruster discharge in the vicinity of the thruster exit allow a reasonable comparison of the measured results for different thruster configurations. It is shown that the plasma potential distribution is almost not sensitive to changes of the electrode potential, but depends on the magnetic field distribution and the electrode placement.

Y. Raitses; D. Staack; N.J. Fisch

2001-10-16T23:59:59.000Z

170

Effects of Detuning on Control of Intersubband Quantum Well Transitions with Chirped Electromagnetic Pulses  

Science Conference Proceedings (OSTI)

We study the interaction of a chirped electromagnetic pulse with intersubband transitions of a double semiconductor quantum well. We specifically consider the interaction of the ground and first excited subbands with the electromagnetic field and use the nonlinear density matrix equations for the description of the system dynamics. These equations are solved numerically for various values of the electron sheet density for a realistic double GaAs/AlGaAs quantum well, and the efficiency of population transfer is discussed with emphasis given to the effects of the detuning of the central frequency of the electromagnetic field from resonance.

Blekos, Konstantinos; Terzis, Andreas F. [Physics Department, School of Natural Sciences, University of Patras, Patras 265 04 (Greece); Simserides, Constantinos [Institute of Materials Science, National Center of Scientific Research Demokritos, 153 10 Athens (Greece); Paspalakis, Emmanuel [Materials Science Department, School of Natural Sciences, University of Patras, Patras 265 04 (Greece)

2010-11-10T23:59:59.000Z

171

Understanding the effects of leakage in superconducting quantum error detection circuits  

E-Print Network (OSTI)

The majority of quantum error detection and correction protocols assume that the population in a qubit does not leak outside of its computational subspace. For many existing approaches, however, the physical qubits do possess more than two energy levels and consequently are prone to such leakage events. Analyzing the effects of leakage is therefore essential to devise optimal protocols for quantum gates, measurement, and error correction. In this work, we present a detailed study of leakage in a two-qubit superconducting stabilizer measurement circuit. We simulate the repeated ancilla-assisted measurement of a single $\\sigma^z$ operator for a data qubit, record the outcome at the end of each measurement cycle, and explore the signature of leakage events in the obtained readout statistics. An analytic model is also developed that closely approximates the results of our numerical simulations. We find that leakage leads to destructive features in the quantum error detection scheme, making additional hardware and software protocols necessary.

Joydip Ghosh; Austin G. Fowler; John M. Martinis; Michael R. Geller

2013-06-04T23:59:59.000Z

172

Amplitudes for Spacetime Regions and the Quantum Zeno Effect: Pitfalls of Standard Path Integral Constructions  

E-Print Network (OSTI)

We argue that under very general conditions, there is a significant complication in amplitudes for spacetimes regions constructed from path integrals. This is the fact that the concrete implementation of the restrictions on paths over an interval of time corresponds, in an operator language, to sharp monitoring at every moment of time in the given time interval. Such processes suffer from the quantum Zeno effect -- the continual monitoring of a quantum system in a Hilbert subspace prevents its state from leaving that subspace. As a consequence, path integral amplitudes defined in this seemingly obvious way have physically and intuitively unreasonable properties and in particular, no sensible classical limit. In this paper we describe this frequently-occurring but little-appreciated phenomenon in some detail, showing clearly the connection with the quantum Zeno effect. We then show that it may be avoided by implementing the restriction on paths in the path integral in a "softer" way. The resulting amplitudes then involve a new coarse graining parameter, which may be taken to be a timescale $\\eps$, describing the softening of the restrictions on the paths. We argue that the complications arising from the Zeno effect are then negligible as long as $\\eps >> 1/ E$, where $E$ is the energy scale of the incoming state. Our criticisms of path integral constructions largely apply to approaches to quantum theory such as the decoherent histories approach or quantum measure theory, which do not specifically involve measurements. We address some criticisms of our approach by Sokolovksi, concerning the relevance of our results to measurement-based models.

J. J. Halliwell; J. M. Yearsley

2013-01-18T23:59:59.000Z

173

Quantum Computation Quantum Information  

E-Print Network (OSTI)

Quantum Computation and Quantum Information Samuel J. Lomonaco, Jr. and Howard E. Brandt editors Searches with a Quantum Robot .............................................. 12 pages Benioff, Paul Perturbation Theory and Numerical Modeling Quantum Logic Operations with a Large of Qubits

Lomonaco Jr., Samuel J.

174

Photon mass and quantum effects of the Aharonov-Bohm type  

Science Conference Proceedings (OSTI)

The magnetic field due to the photon rest mass m{sub ph} modifies the standard results of the Aharonov-Bohm effect for electrons, and of other recent quantum effects. For the effect involving a coherent superposition of beams of particles with opposite electromagnetic properties, by means of a tabletop experiment, the limit m{sub ph}{approx_equal}10{sup -51} g is achievable, improving by 6 orders of magnitude that derived by Boulware and Deser for the Aharonov-Bohm effect.

Spavieri, G. [Centro de Fisica Fundamental, Facultad de Ciencias, Universidad de Los Andes, Merida, 5101-Venezuela (Venezuela); Rodriguez, M. [Departamento de Fisica, FACYT, Universidad de Carabobo, Valencia, 2001-Venezuela (Venezuela)

2007-05-15T23:59:59.000Z

175

Town Hall Meeting | OpenEI Community  

Open Energy Info (EERE)

Town Hall Meeting Town Hall Meeting Home > Groups > Utility Rate Rmckeel's picture Submitted by Rmckeel(297) Contributor 12 June, 2012 - 09:01 Do you want to be more connected with the OpenEI community? Announcing a weekly, public telecon with the OpenEI community at large! Find out how your fellow researchers, students, teachers and energy professionals are using OpenEI, and let us know what needs to change! When: Occurs every Monday 11:30 AM - 12:00 PM (GMT-07:00) Mountain Time, holidays excluded Please use the following information to call in to this meeting: 866-459-9997 #9645075 Town hall default agenda: 30 minutes 5 mins brief introductions - name, company, potential icebreaker (what's your favorite analysis tool, programming language, energy sector..) 5 minutes OpenEI: what's new and coming soon

176

Deck Those Halls! | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Deck Those Halls! Deck Those Halls! Deck Those Halls! December 14, 2010 - 2:24pm Addthis Drew Bittner Web Manager, Office of Energy Efficiency and Renewable Energy It's mid-December, so odds are good you've already decorated your home for the holidays. If so, you're ahead of me; it took us about three days to get the lights on the tree and we still have items to put up at home, not to mention lots of Christmas cards to send out. My point is, many of us are pressed for time in this holiday season. Between braving the stores to shop for gifts, attending parties, digging out winter clothing (and seeing whether it still fits) and so forth, there's not an awful lot of extra time left to think about things like...are the lights on my tree really energy efficient? If you're using LEDs, the answer is an emphatic YES! LEDs are very

177

Deck Those Halls! | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Deck Those Halls! Deck Those Halls! Deck Those Halls! December 14, 2010 - 2:24pm Addthis Drew Bittner Web Manager, Office of Energy Efficiency and Renewable Energy It's mid-December, so odds are good you've already decorated your home for the holidays. If so, you're ahead of me; it took us about three days to get the lights on the tree and we still have items to put up at home, not to mention lots of Christmas cards to send out. My point is, many of us are pressed for time in this holiday season. Between braving the stores to shop for gifts, attending parties, digging out winter clothing (and seeing whether it still fits) and so forth, there's not an awful lot of extra time left to think about things like...are the lights on my tree really energy efficient? If you're using LEDs, the answer is an emphatic YES! LEDs are very

178

Geometric Properties of Transport in Quantum Hall Systems  

E-Print Network (OSTI)

field, develop a current j x in x direction, perpendicular to #12; 2 Th. Richter and R. Seiler the magnetic field and the driving force E y . The current j x and E y are, for small values of E y , related we're able to relate the electric field E y to the change of a first flux through the first handle

179

Symmetry-Protected Quantum Spin Hall Phases in Two Dimensions  

E-Print Network (OSTI)

Symmetry-protected topological (SPT) states are short-range entangled states with symmetry. Nontrivial SPT states have symmetry-protected gapless edge excitations. In 2 dimension (2D), there are an infinite number of ...

Liu, Zheng-Xin

180

Suppression of decoherence effects in the quantum kicked rotor  

E-Print Network (OSTI)

We describe a method allowing transient suppression of decoherence effects on the atom-optics realization of the kicked rotor. The system is prepared in an initial state with a momentum distribution concentrated in an interval much sharper than the Brillouin zone; the measure of the momentum distribution is restricted to this interval of quasimomenta: As most of the atoms undergoing decoherence processes fall outside this detection range and thus are not detected, the measured signal is effectively decoherence-free.

Maxence Lepers; Vronique Zehnl; Jean Claude Garreau

2010-04-15T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Towards equilibration and thermalization between finite quantum systems: The role of dephasing effects and inelastic interactions  

E-Print Network (OSTI)

We demonstrate the approach towards a Gibbs-like equilibrium state, with a common temperature and a chemical potential, of two finite metallic grains, prepared with a different number of noninteracting electrons, connected by a weak link that is susceptible to incoherent and inelastic processes. By developing an analytic method and by using an exact numerical approach, the quantum time evolution of the electrons in the metallic grains is followed. In the absence of decoherring and inelastic effects, equilibration is never reached. Introducing dephasing effects on the link only, using a dephasing probe, the two quantum systems equilibrate, but do not evolve towards a Gibbs-like state. In contrast, by mimicking inelastic interactions with a voltage probe, the metal pieces evolve towards a common Gibbs-like equilibrium state, with the probe.

Manas Kulkarni; Kunal L. Tiwari; Dvira Segal

2012-06-11T23:59:59.000Z

182

ENERGY STAR Score for Residence Halls/Dormitories  

NLE Websites -- All DOE Office Websites (Extended Search)

Residence HallsDormitories in the United States Page 1 ENERGY STAR Score for Residence HallsDormitories in the United States Technical Reference OVERVIEW The ENERGY STAR Score...

183

Corrections to gauge theories in effective quantum gravity with a cutoff  

E-Print Network (OSTI)

We calculate the lowest order quantum gravity contributions to QED beta function in an effective field theory picture with a momentum cutoff. We use a recently proposed 4 dimensional improved momentum cutoff that preserves gauge and Lorentz symmetries. We find that there is non-vanishing quadratic contribution to the photon 2-point function but that does not lead to the running of the original coupling after renormalization. We argue that gravity cannot turn gauge theories asymptotically free.

G. Cynolter; E. Lendvai

2013-07-17T23:59:59.000Z

184

Quantum-confinement versus strain effects in the Zn(Cd)S(Se) family of superlattices  

Science Conference Proceedings (OSTI)

We have investigated the quantum-confinement (QC) and strain effects on the band structures of the Zn(Cd)S(Se) family of binary-compound superlattices (SLs); particularly those with common anions and with common cations. All the studied cases of SLs ... Keywords: 71.20.Nr, 71.55.Gs, 73.21.Fg, 73.61.Ga, II-VI semiconductors, Semiconductor compounds, Superlattices

Ihab M. Obaidat; Nacir Tit

2009-03-01T23:59:59.000Z

185

Universal relaxational dynamics near two-dimensional quantum-critical points  

E-Print Network (OSTI)

We describe the nonzero temperature (T), low frequency (\\omega) dynamics of the order parameter near quantum critical points in two spatial dimensions (d), with a special focus on the regime \\hbar\\omega insulator), to the zero frequency "phase" (n >= 2) or "domain wall" (n=1) relaxation mode near the ordered state. For static properties, we show how a surprising, duality-like transformation allows an exact treatment of the strong-coupling limit for all n. For n=2, we compute the universal T dependence of the superfluid density below the Kosterlitz-Thouless temperature, and discuss implications for the high temperature superconductors. For n=3, our computations of the dynamic structure factor relate to neutron scattering experiments on La_{1.85}Sr_{0.15}CuO_4, and to light scattering experiments on double layer quantum Hall systems. We expect that closely related effective classical wave models will apply also to other quantum critical points in d=2.

Subir Sachdev

1998-10-30T23:59:59.000Z

186

Signe Skott Cooper Hall University of Wisconsin-Madison  

E-Print Network (OSTI)

patient outcomes and greater satisfaction with care. Cooper Hall is the result of a public-private funding

Sheridan, Jennifer

187

FD SOI Hall sensor electronics interfaces for energy measurement  

Science Conference Proceedings (OSTI)

This paper presents a SOI Hall sensor based microsystem for energy measurement. The mixed-mode signal circuitry has been entirely designed and integrated in the experimental 0.5@mm fully depleted SOI 3V technology. It consists of an integrated Hall element, ... Keywords: Energy meter, Hall sensor, Microsystem, SOI

Marija Blagojevic; Maher Kayal; Daniela De Venuto

2006-12-01T23:59:59.000Z

188

Air Temperature in the Undulator Hall  

SciTech Connect

Various analyses have been performed recently to estimate the performance of the air conditioning (HVAC) system planned for the Undulator Hall. This reports summarizes the results and provides an upgrade plan to be used if new requirements are needed in the future. The estimates predict that with the planned loads the tunnel air temperature will be well within the allowed tolerance during normal operation.

Not Available

2010-12-07T23:59:59.000Z

189

Exponential Decay and Fermi's Golden Rule from an Uncontrolled Quantum Zeno Effect  

E-Print Network (OSTI)

The prediction of the Quantum Zeno Effect is based on a product of autocorrelation functions and on the evolution of these functions at short times. We show why in quantum mechanics the autocorrelation between a state and itself some time later cannot be a surrogate for the standard probability. We then reformulate the Quantum Zeno Effect based on the physically meaningful probability, and we find as a condition to observe an inhibition of decay that, following each measurement in a sequence, the system must be prepared in a common eigenstate of the same set of commuting observables. This leads to a simple model of spontaneous decay, in which an excited atom continuously interacts with and is monitored by an incoherent sum of radiation fields. Regardless of the system's evolution otherwise, while monitored the excited atom has exponentially decreasing survival probability at all times. We derive the decay rate and find Fermi's Golden Rule. Continuous monitoring may thus be a mechanism by which to explain the exponential decay law.

P. W. Bryant

2013-09-20T23:59:59.000Z

190

Many-body effects in wide parabolic AlGaAs quantum wells A. Tabata, M. R. Martins, and J. B. B. Oliveira  

E-Print Network (OSTI)

Many-body effects in wide parabolic AlGaAs quantum wells A. Tabata, M. R. Martins, and J. B. B gas in n-type wide parabolic quantum wells. A series of samples with different well widths at the Fermi level at low temperature only in the thinnest parabolic quantum wells. The suppression of the many

Gusev, Guennady

191

Wigner Crystallization in Spin-Polarized Coupled Electron Quantum Layers: Finite Width Effects  

SciTech Connect

We study the effect of finite width on Wigner crystallization in a spin-polarized coupled electron layers. Correlation among carriers are treated beyond the static mean-field theories by using the quantum version of Singwi, Tosi, Land and Sjoelander (qSTLS) theory over a wide range of layer parameters viz. density parameter r{sub sl} and interlayer spacing d. Interestingly we find that the inclusion of finite width of layers lowered the critical density for the onset of Wigner crystal (WC) as compared to the similar recent studies of spin-polarized coupled electron layers without finite width effects.

Nayak, Mukesh G.; Saini, L. K. [Department of Applied Physics, S. V. National Institute of Technology, Surat - 395 007, Gujarat (India)

2011-12-12T23:59:59.000Z

192

Exact solution for excess electrons in quantum mechanically operating solar cells, under cumulative Auger effects  

Science Conference Proceedings (OSTI)

We derive excess carrier populations in quantum wells, embedded in the intrinsic region of p-i-n solar cells. In the process of the analysis, we (a) solve for photo-generated carriers in quantum wells and (b) determine explicit dependence on incident ... Keywords: Auger recombination, material growth, quantum photovoltaics, quantum wells, solar cells, solar spectrum

Argyrios Varonides; Robert Spalletta; Andrew Berger

2007-07-01T23:59:59.000Z

193

Equation of state, universal profiles, scaling and macroscopic quantum effects in Warm Dark Matter galaxies  

E-Print Network (OSTI)

The Thomas-Fermi approach to galaxy structure determines selfconsistently and nonlinearly the gravitational potential of the fermionic WDM particles given their quantum distribution function f(E). Galaxy magnitudes as the halo radius r_h, mass M_h, velocity dispersion and phase space density are obtained. We derive the general equation of state for galaxies (relation between the pressure and the density), and provide an analytic expression. This clearly exhibits two regimes: (i) Large diluted galaxies for M_h > 2.3 10^6 Msun corresponding to temperatures T_0 > 0.017 K, described by the classical self gravitating WDM Boltzman regime and (ii) Compact dwarf galaxies for 1.6 10^6 Msun > M_h>M_{h,min}=30000 (2keV/m)^{16/5} Msun, T_0 10^6 Msun) reflects the WDM perfect gas behaviour. These theoretical results contrasted to robust and independent sets of galaxy data remarkably reproduce the observations. For the small galaxies, 10^6>M_h>M_{h,min} corresponding to effective temperatures T_0 < 0.017 K, the equation of state is galaxy dependent and the profiles are no more universal. These non-universal properties in small galaxies account to the quantum physics of the WDM fermions in the compact regime. Our results are independent of any WDM particle physics model, they only follow from the gravitational interaction of the WDM particles and their fermionic quantum nature.

H. J. de Vega; N. G. Sanchez

2013-10-23T23:59:59.000Z

194

Quantum Money  

Science Conference Proceedings (OSTI)

Quantum Money. Purpose: ... I will present a concrete quantum money scheme based on quantum superpositions of diagrams that encode knots. ...

2011-10-25T23:59:59.000Z

195

Retrocausal Effects as a Consequence of Quantum Mechanics Refined to Accommodate the Principle of Sufficient Reason  

Science Conference Proceedings (OSTI)

The principle of sufficient reason asserts that anything that happens does so for a reason: no definite state of affairs can come into being unless there is a sufficient reason why that particular thing should happen. This principle is usually attributed to Leibniz, although the first recorded Western philosopher to use it was Anaximander of Miletus. The demand that nature be rational, in the sense that it be compatible with the principle of sufficient reason, conflicts with a basic feature of contemporary orthodox physical theory, namely the notion that nature's response to the probing action of an observer is determined by pure chance, and hence on the basis of absolutely no reason at all. This appeal to pure chance can be deemed to have no rational fundamental place in reason-based Western science. It is argued here, on the basis of the other basic principles of quantum physics, that in a world that conforms to the principle of sufficient reason, the usual quantum statistical rules will naturally emerge at the pragmatic level, in cases where the reason behind nature's choice of response is unknown, but that the usual statistics can become biased in an empirically manifest way when the reason for the choice is empirically identifiable. It is shown here that if the statistical laws of quantum mechanics were to be biased in this way then the basically forward-in-time unfolding of empirical reality described by orthodox quantum mechanics would generate the appearances of backward-time-effects of the kind that have been reported in the scientific literature.

Stapp, Henry P.

2011-05-10T23:59:59.000Z

196

Fast Camera Imaging of Hall Thruster Ignition  

SciTech Connect

Hall thrusters provide efficient space propulsion by electrostatic acceleration of ions. Rotating electron clouds in the thruster overcome the space charge limitations of other methods. Images of the thruster startup, taken with a fast camera, reveal a bright ionization period which settles into steady state operation over 50 ?s. The cathode introduces azimuthal asymmetry, which persists for about 30 ?s into the ignition. Plasma thrusters are used on satellites for repositioning, orbit correction and drag compensation. The advantage of plasma thrusters over conventional chemical thrusters is that the exhaust energies are not limited by chemical energy to about an electron volt. For xenon Hall thrusters, the ion exhaust velocity can be 15-20 km/s, compared to 5 km/s for a typical chemical thruster

C.L. Ellison, Y. Raitses and N.J. Fisch

2011-02-24T23:59:59.000Z

197

Dirac Equation and Quantum Relativistic Effects in a Single Trapped Ion  

Science Conference Proceedings (OSTI)

We present a method of simulating the Dirac equation in 3+1 dimensions for a free spin-1/2 particle in a single trapped ion. The Dirac bispinor is represented by four ionic internal states, and position and momentum of the Dirac particle are associated with the respective ionic variables. We show also how to simulate the simplified 1+1 case, requiring the manipulation of only two internal levels and one motional degree of freedom. Moreover, we study relevant quantum-relativistic effects, like the Zitterbewegung and Klein's paradox, the transition from massless to massive fermions, and the relativistic and nonrelativistic limits, via the tuning of controllable experimental parameters.

Lamata, L.; Leon, J. [Instituto de Matematicas y Fisica Fundamental, CSIC, Serrano 113-bis, 28006 Madrid (Spain); Schaetz, T. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany); Solano, E. [Physics Department, ASC, and CeNS, Ludwig-Maximilians-Universitaet, Theresienstrasse 37, 80333 Munich (Germany); Seccion Fisica, Departamento de Ciencias, Pontificia Universidad Catolica del Peru, Apartado Postal 1761, Lima (Peru)

2007-06-22T23:59:59.000Z

198

Quantum incompressibility of a falling Rydberg atom, and a gravitationally-induced charge separation effect in superconducting systems  

E-Print Network (OSTI)

Freely falling point-like objects converge towards the center of the Earth. Hence the gravitational field of the Earth is inhomogeneous, and possesses a tidal component. The free fall of an extended quantum object such as a hydrogen atom prepared in a high principal-quantum-number stretch state, i.e., a circular Rydberg atom, is predicted to fall more slowly that a classical point-like object, when both objects are dropped from the same height from above the Earth. This indicates that, apart from "quantum jumps," the atom exhibits a kind of "quantum incompressibility" during free fall in inhomogeneous, tidal gravitational fields like those of the Earth. A superconducting ring-like system with a persistent current circulating around it behaves like the circular Rydberg atom during free fall. Like the electronic wavefunction of the freely falling atom, the Cooper-pair wavefunction is "quantum incompressible." The ions of the ionic lattice of the superconductor, however, are not "quantum incompressible," since they do not possess a globally coherent quantum phase. The resulting difference during free fall in the response of the nonlocalizable Cooper pairs of electrons and the localizable ions to inhomogeneous gravitational fields is predicted to lead to a charge separation effect, which in turn leads to a large repulsive Coulomb force that opposes the convergence caused by the tidal, attractive gravitational force on the superconducting system. A "Cavendish-like" experiment is proposed for observing the charge separation effect induced by inhomogeneous gravitational fields in a superconducting circuit. This experiment would demonstrate the existence of a novel coupling between gravity and electricity via macroscopically coherent quantum matter.

Raymond Y. Chiao

2010-03-05T23:59:59.000Z

199

Secretary Moniz Leads DOE Town Hall | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Moniz Leads DOE Town Hall Moniz Leads DOE Town Hall Secretary Moniz Leads DOE Town Hall May 22, 2013 - 6:30pm Addthis Secretary Moniz and Deputy Secretary Poneman address questions from Department of Energy employees in a town hall. Erin R. Pierce Erin R. Pierce Digital Communications Specialist, Office of Public Affairs Secretary Moniz: Week One Watch the swearing-in ceremony. See a video recap of Secretary Moniz's first day in office. View a slideshow of photos from the DOE Town Hall. "I have a lot of hope and aspirations for what we're going to accomplish here together." So began Energy Secretary Ernest Moniz as he led a town hall discussion with Energy Department employees on his second day in office. Held at DOE headquarters in Washington, D.C., Secretary Moniz shared his

200

Diversity and Inclusion Town Hall Program Book | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Diversity and Inclusion Town Hall Program Book Diversity and Inclusion Town Hall Program Book Diversity and Inclusion Town Hall Program Book As part of a larger effort to create a culture that values diversity, we have been conducting focus groups to engage in a dialog and hear feedback on how diversity can be improved. At the Town Hall, DOE employees will hear the results of these discussions. View the program booklet from the Diversity and Inclusion Town Hall below. For more information about the Department's diversity and inclusion programs, visit http://energy.gov/diversity/services/diversity-and-inclusion Diversity Town Hall Program Booklet_0.pdf More Documents & Publications Diversity Action Letter from Secretary Chu Secretary Chu's Diversity Action Letter Government-Wide Diversity and Inclusion Strategic Plan (2011), Office of

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Controlling atomistic processes on Pb films via quantum size effects and lattice rotation  

Science Conference Proceedings (OSTI)

The two main techniques used to record the data in this dissertation were Spot Profile Analysis - Low Energy Electron Diffraction (SPA-LEED) and Scanning Tunneling Microscopy (STM). A specific data analysis technique for LEED data called G(S) curves is described in depth. G(S) curves can provide a great deal of structural information about the surface; including step heights, island size, and island separation. The effects of quantum size effects (QSE) on the diffusion and critical island sizes of Pb and In on Pb #12;films are reported. Pb depositions on the 2D In phases {radical}3 and {radical}31 to see how the phases affect the Pb growth and its strong QSE are reported.

Binz, Steven

2012-06-14T23:59:59.000Z

202

Rebuilding It Better: Greensburg, Kansas, City Hall | Open Energy  

Open Energy Info (EERE)

Hall Hall Jump to: navigation, search Name Rebuilding It Better: Greensburg, Kansas, City Hall Agency/Company /Organization National Renewable Energy Laboratory Focus Area Agriculture, Buildings, Economic Development, Energy Efficiency, Water Conservation, Renewable Energy, Ground Source Heat Pumps, - Solar Pv, Wind Phase Bring the Right People Together, Create a Vision, Evaluate Options, Develop Goals, Develop Finance and Implement Projects, Create Early Successes Resource Type Case studies/examples Availability Publicly available--Free Publication Date 9/1/2010 Website http://apps1.eere.energy.gov/b Locality Greensburg, Kansas References Rebuilding It Better: Greensburg, Kansas, City Hall [1] Contents 1 Overview 2 Highlights 3 Environmental Aspects 4 References

203

Modeling of Hall thruster lifetime and erosion mechanisms.  

E-Print Network (OSTI)

??Hall thrusters and other types of electric propulsion have become a tempting alternative to traditional chemical propulsion systems for in-space applications due to the high (more)

Cheng, Shannon Yun-Ming, 1978-

2007-01-01T23:59:59.000Z

204

Building America Top Innovations Hall of Fame Profile - Integration...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Integration of HVAC System Design with Simplified Duct Distribution Building America Top Innovations Hall of Fame Profile - Integration of HVAC System Design with Simplified Duct...

205

Cryoscopic Data for Hall-Hroult Bath Containing Magnesium ...  

Science Conference Proceedings (OSTI)

Presentation Title, Cryoscopic Data for Hall-Hroult Bath Containing Magnesium Fluoride, Calcium Fluoride, Potassium Cryolite, and Sodium Chloride. Author(s)...

206

Rebuilding It Better: Greensburg, Kansas. City Hall (Brochure...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

This brochure details the energy efficient and sustainable aspects of the LEED Platinum-designated City Hall building in Greensburg, Kansas....

207

Rebuilding It Better: Greensburg, Kansas, City Hall (Brochure)  

SciTech Connect

This brochure details the energy efficient and sustainable aspects of the LEED Platinum-designated City Hall building in Greensburg, Kansas.

Not Available

2010-09-01T23:59:59.000Z

208

Building America Top Innovations Hall of Fame Profile - Building...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Science-Based Climate Maps Building America Top Innovations Hall of Fame Profile - Building Science-Based Climate Maps 43abainnovbuildingscienceclimatemaps...

209

Behavior, comfort, and energy consumption in student residence halls.  

E-Print Network (OSTI)

??New residence halls differ from their predecessors because of sophisticated systems, concern for energy efficiency, and attention to student satisfaction. Nevertheless, older facilities represent the (more)

Collins, Thomas Daniel, 1979-

2010-01-01T23:59:59.000Z

210

Building America Top Innovations Hall of Fame Profile - Basement...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Basement Insulation Systems Building America Top Innovations Hall of Fame Profile - Basement Insulation Systems This Building America Innovations profile describes Building America...

211

Quantum field theory in curved graphene spacetimes, Lobachevsky geometry, Weyl symmetry, Hawking effect, and all that  

E-Print Network (OSTI)

We extensively discuss the theoretical framework to make curved monolayer graphene a realization of quantum field theory in curved spacetime. We rely upon a model of the electron-phonon interaction that reproduces the standard semiclassical Dirac quantum field in a curved spacetime. This model holds for very long wavelengths of the graphene conductivity electrons involved. Provided the full description of the phonon-electron interaction is of a modified gravity-type, the core of the results presented here apply, with due changes, to that case too. Using local Weyl symmetry, we probe into the possibility to reproduce a Hawking effect. For the sake of making the test easier in a laboratory, the whole study is carried out for the case of purely spatial curvatures, and for conformally flat spacetimes. Since we show that for the sphere there is no intrinsic horizon, the focus is on the infinite different surfaces of constant negative Gaussian curvature. Even though, in those cases, deep reasons of Lobachevsky geometry seem to lead to unreachable event horizons, we show under which conditions the horizon is within reach. The Hawking effect, then, takes place on the Beltrami surface. We also explicitly study the spacetimes of the other two pseudospheres, and show their relation to de Sitter, and BTZ black-hole spacetimes. In the same limit that gives a reachable event horizon, these two cases, essentially, reduce to Beltrami. This, together with the fact that all the infinite surfaces in point are applicable to either one of the three pseudospheres, make us conjecture about the possibility for a Hawking effect for a generic surface of the family. The Hawking effect here manifests itself through a finite (Hawking) temperature electronic local density of states, that we exhibit.

Alfredo Iorio; Gaetano Lambiase

2013-08-01T23:59:59.000Z

212

New quantum gravity effect, dark energy, accelerating universe, black hole and experimental scheme using superfluid Helium and atom interferometer  

E-Print Network (OSTI)

Considerable attention has been focused on Verlinde's recent work, claiming that Newton's gravity is not a fundamental force. In a recent work (arXiv:1012.5858), we give further the logic basis and basic clues to derive the Newton's gravity, inertia law and Einstein's weak equivalence principle. In this work, we show that if the gravity is not a fundamental force, in special case, it could be repulsive when quantum wavepacket effect is considered. This quantum gravity effect leads to several physical effects: (1) It is consistent with the universe with accelerating expansion, if the gravity and quantum effect of the fluctuating 'vacuum' (dark energy) is considered. The role of the cosmological constant is naturally interpreted when the gravity and quantum effect of the whole 'vacuum' background is considered. (2) It leads to new idea about black hole information paradox, no-hair theorem and Hawking radiation. (3) With a sphere full of superfluid Helium, we propose a feasible experimental scheme to test our idea with an atom interferometer placed in the sphere. Our calculations show that the accuracy Delta g/g below 10^(-8) could be used to test our idea, which satisfies the present experimental technique of atom interferometer.

Hongwei Xiong

2011-01-03T23:59:59.000Z

213

Schedule and cost estimate for an innovative Boston Harbor concert hall  

E-Print Network (OSTI)

This thesis formulates a cost estimate and schedule for constructing the Boston Concert Hall, an innovative hypothetical building composed of two concert halls and a restaurant. Concert Halls are complex and expensive ...

Coste, Amelie, 1982-

2004-01-01T23:59:59.000Z

214

A Quantum Bousso Bound  

E-Print Network (OSTI)

The Bousso bound requires that one quarter the area of a closed codimension two spacelike surface exceeds the entropy flux across a certain lightsheet terminating on the surface. The bound can be violated by quantum effects such as Hawking radiation. It is proposed that at the quantum level the bound be modified by adding to the area the quantum entanglement entropy across the surface. The validity of this quantum Bousso bound is proven in a two-dimensional large N dilaton gravity theory.

Andrew Strominger; David Thompson

2003-03-10T23:59:59.000Z

215

Kinematic study of the effect of dispersion in quantum vacuum emission from strong laser pulses  

E-Print Network (OSTI)

A strong light pulse propagating in a nonlinear medium causes an effective change in the local refractive index. With a suitable tuning of the pulse velocity, the leading and trailing edge of the pulse were predicted to behave as analogue black and white horizons in the limit of a dispersionless medium. In this paper, we study a more realistic situation where the frequency dispersion of the medium is fully taken into account. As soon as positive frequency modes with negative norm are present in the comoving frame, spontaneous emission of quantum vacuum radiation is expected to arise independently of the presence of horizons. We finally investigate the kinematic constraints put on the emission and we show that the optimal directions to observe Hawking-like emission form a narrow angle with the direction of propagation of the pulse.

Stefano Finazzi; Iacopo Carusotto

2012-04-16T23:59:59.000Z

216

Clustered Geometries Exploiting Quantum Coherence Effects for Efficient Energy Transfer in Light Harvesting  

E-Print Network (OSTI)

Elucidating quantum coherence effects and geometrical factors for efficient energy transfer in photosynthesis has the potential to uncover non-classical design principles for advanced organic materials. We study energy transfer in a linear light-harvesting model to reveal that dimerized geometries with strong electronic coherences within donor and acceptor pairs exhibit significantly improved efficiency, which is in marked contrast to predictions of the classical F\\"orster theory. We reveal that energy tuning due to coherent delocalization of photoexcitations is mainly responsible for the efficiency optimization. This coherence-assisted energy-tuning mechanism also explains the energetics and chlorophyll arrangements in the widely-studied Fenna-Matthews-Olson complex. We argue that a clustered network with rapid energy relaxation among donors and resonant energy transfer from donor to acceptor states provides a basic formula for constructing efficient light-harvesting systems, and the general principles revea...

Ai, Qing; Jin, Bih-Yaw; Cheng, Yuan-Chung

2013-01-01T23:59:59.000Z

217

The dispersion interaction between quantum mechanics and effective fragment potential molecules  

SciTech Connect

A method for calculating the dispersion energy between molecules modeled with the general effective fragment potential (EFP2) method and those modeled using a full quantum mechanics (QM) method, e.g., Hartree-Fock (HF) or second-order perturbation theory, is presented. C6 dispersion coefficients are calculated for pairs of orbitals using dynamic polarizabilities from the EFP2 portion, and dipole integrals and orbital energies from the QM portion of the system. Dividing by the sixth power of the distance between localized molecular orbital centroids yields the first term in the commonly employed London series expansion. A C8 term is estimated from the C6 term to achieve closer agreement with symmetry adapted perturbation theory values. Two damping functions for the dispersion energy are evaluated. By using terms that are already computed during an ordinary HF or EFP2 calculation, the new method enables accurate and extremely rapid evaluation of the dispersion interaction between EFP2 and QM molecules.

Smith, Quentin A.; Ruedenberg, Klaus; Gordon, Mark S.; Slipchenko, Lyudmila

2012-06-26T23:59:59.000Z

218

Undulator Hall Air Temperature Fault Scenarios  

SciTech Connect

Recent experience indicates that the LCLS undulator segments must not, at any time following tuning, be allowed to change temperature by more than about {+-}2.5 C or the magnetic center will irreversibly shift outside of acceptable tolerances. This vulnerability raises a concern that under fault conditions the ambient temperature in the Undulator Hall might go outside of the safe range and potentially could require removal and retuning of all the segments. In this note we estimate changes that can be expected in the Undulator Hall air temperature for three fault scenarios: (1) System-wide power failure; (2) Heating Ventilation and Air Conditioning (HVAC) system shutdown; and (3) HVAC system temperature regulation fault. We find that for either a system-wide power failure or an HVAC system shutdown (with the technical equipment left on), the short-term temperature changes of the air would be modest due to the ability of the walls and floor to act as a heat ballast. No action would be needed to protect the undulator system in the event of a system-wide power failure. Some action to adjust the heat balance, in the case of the HVAC power failure with the equipment left on, might be desirable but is not required. On the other hand, a temperature regulation failure of the HVAC system can quickly cause large excursions in air temperature and prompt action would be required to avoid damage to the undulator system.

Sevilla, J.

2010-11-17T23:59:59.000Z

219

Magnetics News  

Science Conference Proceedings (OSTI)

... Hall Effect in a Quantum Gas Is Step ... Discovered 'Quantum Spin Liquid', the Beauty ... A TECHNOLOGY TRANSFER AND FEDERAL MARKETPLACE ...

2010-05-24T23:59:59.000Z

220

Hole mobility enhancement in In0.41 Ga0.59 Sb quantum-well field-effect transistors  

E-Print Network (OSTI)

The impact of ?110? uniaxial strain on the characteristics of p-channel In[subscript 0.41]Ga[subscript 0.59]Sb quantum-well field-effect transistors (QW-FETs) is studied through chip-bending experiments. Uniaxial strain ...

Xia, Ling

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Quantum groups  

Science Conference Proceedings (OSTI)

The theory of Quantum groups, although rather young, since the expression Quantum ... introduction of a suitable form of the quantum group, the algebra A...

222

Quantum interference and control of the dynamic Franz-Keldysh effect: Generation and detection of terahertz space-charge fields  

Science Conference Proceedings (OSTI)

The Dynamic Franz Keldysh Effect (DFKE) is produced and controlled in bulk gallium arsenide by quantum interference without the aid of externally applied fields and is spatially and temporally resolved using ellipsometric pump-probe techniques. The {approx}3 THz internal driving field for the DFKE is a transient space-charge field that is associated with a critically damped coherent plasma oscillation produced by oppositely traveling ballistic electron and hole currents that are injected by two-color quantum interference techniques. The relative phase and polarization of the two pump pulses can be used to control the DFKE.

Wang, Rui [Laboratory for Photonics and Quantum Electronics, 138 IATL, University of Iowa, Iowa City, Iowa 52242 (United States) [Laboratory for Photonics and Quantum Electronics, 138 IATL, University of Iowa, Iowa City, Iowa 52242 (United States); Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045 (United States); Jacobs, Paul; Smirl, Arthur L. [Laboratory for Photonics and Quantum Electronics, 138 IATL, University of Iowa, Iowa City, Iowa 52242 (United States)] [Laboratory for Photonics and Quantum Electronics, 138 IATL, University of Iowa, Iowa City, Iowa 52242 (United States); Zhao, Hui [Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045 (United States)] [Department of Physics and Astronomy, University of Kansas, Lawrence, Kansas 66045 (United States)

2013-06-24T23:59:59.000Z

223

Quantum Physics and Nanotechnology  

E-Print Network (OSTI)

Experimental studies of infinite (unrestricted at least in one direction) quantum particle motion using probe nanotechnologies have revealed the necessity of revising previous concepts of their motion. Particularly, quantum particles transfer quantum motion nonlocality energy beside classical kinetic energy, in other words, they are in two different kinds of motion simultaneously. The quantum component of the motion energy may be quite considerable under certain circumstances. Some new effects were predicted and proved experimentally in terms of this phenomenon. A new prototype refrigerating device was tested, its principle of operation being based on the effect of transferring the quantum component of the motion energy.

Vladimir K. Nevolin

2011-06-06T23:59:59.000Z

224

Rebuilding It Better: Greensburg, Kansas. City Hall (Brochure)  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

City Hall City Hall Destroyed in the tornado, City Hall has been rebuilt green incorporating solar panels, ground source heat pumps, reclaimed materials, and a vegetated roof. The building serves as a symbol of Greensburg's vitality and leadership in becoming a sustainable community where social, environmental, and economic concerns are held in balance. The new Greensburg City Hall is projected to achieve more than 38% energy savings compared to a similar building built to standard code due in part to the 4.8-kilowatt (kW) rooftop photovoltaic (PV) system and ground source heat pumps. REBUILDING IT BETTER: GREENSBURG, KANSAS LEED® Platinum Completed in October 2009, Greensburg City Hall achieved the U.S. Green Building Council's Leadership in Energy and Environmental Design

225

Missed Today's Town Hall with Sec. Chu? | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Missed Today's Town Hall with Sec. Chu? Missed Today's Town Hall with Sec. Chu? Missed Today's Town Hall with Sec. Chu? January 26, 2011 - 4:02pm Addthis We have the video of today's online town hall event with Secretary Chu up and ready for your viewing. Check it out here. Ginny Simmons Ginny Simmons Former Managing Editor for Energy.gov, Office of Public Affairs We have the video of today's online town hall event with Secretary Chu up and ready for your viewing. Check it out here. During the event, Secretary Chu highlighted several parts of the President Obama's clean energy and innovation agenda: Ending taxpayer subsidies for fossil fuels so we can increase our investments in clean energy by a third; Creating three new Energy Innovation Hubs; Putting one million advanced technology vehicles on the road by

226

The effect of encapsulation on the morphology and chemical composition of InAs/GaAs quantum dots grown by molecular beam epitaxy  

Science Conference Proceedings (OSTI)

In order to fabricate an effective device structure based on InAs quantum dots (QDs), the QD layers must be encapsulated within a matrix that has a wider band gap. This encapsulation is usually achieved by the overgrowth of GaAs. Coherent strained InAs/GaAs ... Keywords: encapsulation, indium arsenide, quantum dots, transmission electron microscopy

D. Zhi; M. Wei; R. E. Dunin-Borkowski; P. A. Midgley; D. W. Pashley; T. S. Jones; B. A. Joyce; P. F. Fewster; P. J. Goodhew

2004-06-01T23:59:59.000Z

227

The Honorable,Edward Rendell, '. City Hall  

Office of Legacy Management (LM)

I:! i394 I:! i394 .\ . The Honorable,Edward Rendell, '. City Hall Philadelphia, Pennsylvania 19107 Dear Mayor Rendell : ', ,' . , Secretary of Energy Hazel O',teary has announced-a new approach.to.openness in the Department of Energy (DDE) and its communications with the public. . In support of this initiative, we are.pleased to forward the enclosed information related to the,former. Penn Salt Manufacturing' Co. site in your jurisdiction that performed.work for DOE or its predecessor agencies. This information is provided for yqur information,~use, and retention. _- DOE's~ Formerly~;Utili,zed Sites Remedial Action Program is responsible for '. identification of sites used by DOE's predecessor agencies, determining their current radiologic,al condition and, where it has aut.hori,ty;performing

228

Quantum Cryptography and Quantum Computation  

E-Print Network (OSTI)

Quantum Cryptography and Quantum Computation Network Security Course Project Report by Hidayath.2 Bases of the Hilbert space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3 Quantum principle . . . . . . . . . . . . . . . . . . . . . . 5 3 Quantum Cryptography 6 3.1 The BB84 protocol

North Carolina at Chapel Hill, University of

229

Enhanced Hall slope in wide AlxGax-1As parabolic wells A. M. Ortiz de Zevallos, N. C. Mamani, G. M. Gusev, A. A. Quivy, and T. E. Lamas  

E-Print Network (OSTI)

Enhanced Hall slope in wide AlxGax-1As parabolic wells A. M. Ortiz de Zevallos, N. C. Mamani, G. M report measurements of the Hall effect in 1000­4000 ? wide AlxGax-1As parabolic wells with quasi- two resistance for wide parabolic wells is found to be enhanced when the temperature decreases. We attribute

Gusev, Guennady

230

Quantum Multiobservable Control  

E-Print Network (OSTI)

We present deterministic algorithms for the simultaneous control of an arbitrary number of quantum observables. Unlike optimal control approaches based on cost function optimization, quantum multiobservable tracking control (MOTC) is capable of tracking predetermined homotopic trajectories to target expectation values in the space of multiobservables. The convergence of these algorithms is facilitated by the favorable critical topology of quantum control landscapes. Fundamental properties of quantum multiobservable control landscapes that underlie the efficiency of MOTC, including the multiobservable controllability Gramian, are introduced. The effects of multiple control objectives on the structure and complexity of optimal fields are examined. With minor modifications, the techniques described herein can be applied to general quantum multiobjective control problems.

Raj Chakrabarti; Rebing Wu; Herschel Rabitz

2008-05-12T23:59:59.000Z

231

Kondo Resonance in a Mesoscopic Ring Coupled to a Quantum Dot: Exact Results for the Aharonov-Bohm-Casher Effects  

Science Conference Proceedings (OSTI)

We study the persistent currents induced by both the Aharonov-Bohm and Aharonov-Casher effects in a one-dimensional mesoscopic ring coupled to a sidebranch quantum dot at Kondo resonance. For privileged values of the Aharonov-Bohm-Casher fluxes, the problem can be mapped onto an integrable model, exactly solvable by a Bethe ansatz. In the case of a pure magnetic Aharonov-Bohm flux, we find that the presence of the quantum dot has no effect on the persistent current. In contrast, the Kondo resonance interferes with the spin-dependent Aharonov-Casher effect to induce a current which, in the strong-coupling limit, is independent of the number of electrons in the ring.

Eckle, H.-P.; Johannesson, H.; Stafford, C. A.

2001-07-02T23:59:59.000Z

232

An improved pyrolysis route to synthesize carbon-coated CdS quantum dots with fluorescence enhancement effect  

SciTech Connect

Well-dispersed carbon-coated CdS (CdS-C) quantum dots were successfully prepared via the improved pyrolysis of bis(1-dodecanethiol)-cadmium(II) under nitrogen atmosphere. This simple method effectively solved the sintered problem resulted from conventional pyrolysis process. The experimental results indicated that most of the as-prepared nanoparticles displayed well-defined core-shell structures. The CdS cores with diameter of {approx}5 nm exhibited hexagonal crystal phase, the carbon shells with thickness of {approx}2 nm acted as a good dispersion medium to prevent CdS particles from aggregation, and together with CdS effectively formed a monodisperse CdS-Carbon nanocomposite. This composite presented a remarkable fluorescence enhancement effect, which indicated that the prepared nanoparticles might be a promising photoresponsive material or biosensor. This improved pyrolysis method might also offer a facile way to prepare other carbon-coated semiconductor nanostructures. - Graphical abstract: We demonstrated a facile approach to synthesize well-dispersed carbon-coated CdS quantum dots. The as-prepared nanoparticles presented remarkable fluorescence enhancement effect. Highlights: > Carbon-coated CdS quantum dots were synthesized by an one-step pyrolysis method. > Well-dispersed CdS-carbon nanoparticles were obtained by an acid treatment process. > As-prepared nanoparticles presented remarkable fluorescence enhancement effect.

Zhang Kejie [Key Laboratory for Soft Chemistry and Functional Materials of Ministry Education, Nanjing University of Science and Technology, Nanjing 210094 (China); Liu Xiaoheng, E-mail: xhliu@mail.njust.edu.cn [Key Laboratory for Soft Chemistry and Functional Materials of Ministry Education, Nanjing University of Science and Technology, Nanjing 210094 (China)

2011-10-15T23:59:59.000Z

233

Macroscopic quantum behaviour of periodic quantum systems  

E-Print Network (OSTI)

In this paper we introduce a simple procedure for computing the macroscopic quantum behaviour of periodic quantum systems in the high energy regime. The macroscopic quantum coherence is ascribed to a one-particle state, not to a condensate of a many-particle system; and we are referring to a system of high energy but with few degrees of freedom. We show that, in the first order of approximation, the quantum probability distributions converge to its classical counterparts in a clear fashion, and that the interference effects are strongly suppressed. The harmonic oscillator provides a testing ground for these ideas and yields excellent results.

A. Martn-Ruiz; J. Bernal; Adrin Carbajal-Domnguez

2013-09-02T23:59:59.000Z

234

Quantum error control codes  

E-Print Network (OSTI)

It is conjectured that quantum computers are able to solve certain problems more quickly than any deterministic or probabilistic computer. For instance, Shor's algorithm is able to factor large integers in polynomial time on a quantum computer. A quantum computer exploits the rules of quantum mechanics to speed up computations. However, it is a formidable task to build a quantum computer, since the quantum mechanical systems storing the information unavoidably interact with their environment. Therefore, one has to mitigate the resulting noise and decoherence effects to avoid computational errors. In this dissertation, I study various aspects of quantum error control codes - the key component of fault-tolerant quantum information processing. I present the fundamental theory and necessary background of quantum codes and construct many families of quantum block and convolutional codes over finite fields, in addition to families of subsystem codes. This dissertation is organized into three parts: Quantum Block Codes. After introducing the theory of quantum block codes, I establish conditions when BCH codes are self-orthogonal (or dual-containing) with respect to Euclidean and Hermitian inner products. In particular, I derive two families of nonbinary quantum BCH codes using the stabilizer formalism. I study duadic codes and establish the existence of families of degenerate quantum codes, as well as families of quantum codes derived from projective geometries. Subsystem Codes. Subsystem codes form a new class of quantum codes in which the underlying classical codes do not need to be self-orthogonal. I give an introduction to subsystem codes and present several methods for subsystem code constructions. I derive families of subsystem codes from classical BCH and RS codes and establish a family of optimal MDS subsystem codes. I establish propagation rules of subsystem codes and construct tables of upper and lower bounds on subsystem code parameters. Quantum Convolutional Codes. Quantum convolutional codes are particularly well-suited for communication applications. I develop the theory of quantum convolutional codes and give families of quantum convolutional codes based on RS codes. Furthermore, I establish a bound on the code parameters of quantum convolutional codes - the generalized Singleton bound. I develop a general framework for deriving convolutional codes from block codes and use it to derive families of non-catastrophic quantum convolutional codes from BCH codes. The dissertation concludes with a discussion of some open problems.

Abdelhamid Awad Aly Ahmed, Sala

2008-05-01T23:59:59.000Z

235

Parametric Investigations of Miniaturized Cylindrical and Annular Hall Thrusters  

DOE Green Energy (OSTI)

A cylindrical geometry Hall thruster may overcome certain physical and technological limitations in scaling down of Hall thrusters to miniature sizes. The absence of the inner wall and use of the cusp magnetic field can potentially reduce heating of the thruster parts and erosion of the channel. A 2.6 cm miniaturized Hall thruster of a flexible design was built and successfully operated in the power range of 50-300 W. Comparison of preliminary results obtained for cylindrical and annular thruster configurations is presented.

A. Smirnov; Y. Raitses; N.J. Fisch

2001-10-16T23:59:59.000Z

236

Quantum Tetrahedra  

E-Print Network (OSTI)

We discuss in details the role of Wigner 6j symbol as the basic building block unifying such different fields as state sum models for quantum geometry, topological quantum field theory, statistical lattice models and quantum computing. The apparent twofold nature of the 6j symbol displayed in quantum field theory and quantum computing -a quantum tetrahedron and a computational gate- is shown to merge together in a unified quantum-computational SU(2)-state sum framework.

Mauro Carfora; Annalisa Marzuoli; Mario Rasetti

2010-01-25T23:59:59.000Z

237

Nuclear quantum effects in the structure and lineshapes of the N2 NEXAFS spectrum  

SciTech Connect

We study the relative ability of several models of the X-ray absorption spectrum to capture the Franck-Condon structure apparent from an experiment on gaseous nitrogen. In doing so, we adopt the Born-Oppenheimer approximation and a constrained density functional theory method for computing the energies of the X-ray-excited molecule. Starting from an otherwise classical model for the spectrum, we systematically introduce more realistic physics, first by substituting the quantum mechanical nuclear radial density in the bond separation R for the classical radial density, then by adding the effect of zero-point energy and other level shifts, and finally by including explicit rovibrational quantization of both the ground and excited states. The quantization is determined exactly, using a discrete variable representation. We show that the NEXAFS spectrum can be predicted semiquantiatively within this framework. We also address the possibility of non-trivial temperature dependence in the spectrum. Finally, we show that it is possible to improve the predicted spectrum by using constrained DFT in combination with more accurate potentials.

Fatehi, Shervin; Schwartz, Craig P.; Saykally, Richard J.; Prendergast, David

2009-12-04T23:59:59.000Z

238

Clustered Geometries Exploiting Quantum Coherence Effects for Efficient Energy Transfer in Light Harvesting  

E-Print Network (OSTI)

Elucidating quantum coherence effects and geometrical factors for efficient energy transfer in photosynthesis has the potential to uncover non-classical design principles for advanced organic materials. We study energy transfer in a linear light-harvesting model to reveal that dimerized geometries with strong electronic coherences within donor and acceptor pairs exhibit significantly improved efficiency, which is in marked contrast to predictions of the classical F\\"orster theory. We reveal that energy tuning due to coherent delocalization of photoexcitations is mainly responsible for the efficiency optimization. This coherence-assisted energy-tuning mechanism also explains the energetics and chlorophyll arrangements in the widely-studied Fenna-Matthews-Olson complex. We argue that a clustered network with rapid energy relaxation among donors and resonant energy transfer from donor to acceptor states provides a basic formula for constructing efficient light-harvesting systems, and the general principles revealed here can be generalized to larger systems and benefit future innovation of efficient molecular light-harvesting materials.

Qing Ai; Tzu-Chi Yen; Bih-Yaw Jin; Yuan-Chung Cheng

2013-07-22T23:59:59.000Z

239

Quantum noise and radiation pressure effects in high power optical interferometers  

E-Print Network (OSTI)

In recent years, a variety of mechanical systems have been approaching quantum limits to their sensitivity of continuous position measurements imposed by the Heisenberg Uncertainty Principle. Most notably, gravitational ...

Corbitt, Thomas Randall

2008-01-01T23:59:59.000Z

240

Effects of stacking faults on the electronic structures of quantum rods  

E-Print Network (OSTI)

nanorod, stacking fault, CdSe, empirical pseudopotentialstructure quantum dots, like CdSe and InP. The stackingabout 1 meV/atom in CdSe [7]), and it depends sensitively on

Wang, Lin-Wang

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Sec. Chu Online Town Hall | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Online Town Hall Online Town Hall Sec. Chu Online Town Hall Addthis Description Secretary Steven Chu hosted an online town hall to discuss the clean energy and innovation agenda President Obama laid out in his 2011 State of the Union address. (January 26, 2011) Speakers Secretary Steven Chu Duration 51:59 Topic Tax Credits, Rebates, Savings Energy Sources Energy Economy Credit Energy Department Video SECRETARY STEVEN CHU: All right, thank you. I'd like to first thank you for being here and all those out there in ether-land, cyberspace also, for joining us. I just want to briefly make a couple comments before handing it over to questions. Last night, President Obama laid out strategy for America to create jobs and win the future, and there were central themes going throughout his

242

Missed the Town Hall with Secretary Chu? | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Missed the Town Hall with Secretary Chu? Missed the Town Hall with Secretary Chu? Missed the Town Hall with Secretary Chu? January 31, 2011 - 11:40am Addthis Ginny Simmons Ginny Simmons Former Managing Editor for Energy.gov, Office of Public Affairs Editor's Note: This entry has been cross-posted from DOE's Energy Blog. We have the video of the online town hall event with Secretary Chu up and ready for your viewing. Check it out below. During the event, Secretary Chu highlighted several parts of the President Obama's clean energy and innovation agenda: Ending taxpayer subsidies for fossil fuels so we can increase our investments in clean energy by a third; Creating three new Energy Innovation Hubs; Putting one million advanced technology vehicles on the road by 2015; A "Sun Shot" initiative to make solar energy cost-competitive with

243

Town Hall with Secretary Moniz | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Town Hall with Secretary Moniz Town Hall with Secretary Moniz Town Hall with Secretary Moniz July 18, 2013 - 3:42pm Addthis Secretary Moniz speaks at a townhall with DOE employees on the Departmental reorganization. Dan Leistikow Dan Leistikow Former Director, Office of Public Affairs In a town hall meeting with Department staff, Energy Secretary Ernest Moniz spoke about his plans for a reorganization of the Energy Department's management structure. The plans will help better achieve the Department's key priorities and those of the President, including implementing the President's Climate Action Plan, "all of the above" energy strategy and nuclear security agenda. After his remarks, Moniz, joined by Deputy Secretary Dan Poneman, took questions from the audience in the Forrestal Auditorium as well as email

244

NE-24 Gilman Hall, University of California, Certification Documentation  

Office of Legacy Management (LM)

Gilman Hall, University of California, Gilman Hall, University of California, Certification Documentation Berkeley, California, Conditional Verlette Gatlin, MA-232 I am attaching for entry into the Public Document Room, two copies of the subject documentation. These documents are the backup data for the conditional certification that the site is radiologically acceptable for restricted use as noted in the certification statement published in the Federal Register. Inasmuch as the conditional certification is made public through the Federal Register, it is prudent that the attached backup documentation also be available to the public. The docket consists of: 1. Introduction: Introduction to the certification docket for Gilman Hall, University of California, Berkeley, California. 2. Exhibit I: Summary of activities at Gilman Hall, University of

245

Modeling of Hall thruster lifetime and erosion mechanisms  

E-Print Network (OSTI)

Hall thrusters and other types of electric propulsion have become a tempting alternative to traditional chemical propulsion systems for in-space applications due to the high specific impulses (Isp) they provide. Large Isp ...

Cheng, Shannon Yun-Ming, 1978-

2007-01-01T23:59:59.000Z

246

Theoretical and experimental investigation of Hall thruster miniaturization  

E-Print Network (OSTI)

Interest in small-scale space propulsion continues to grow with the increasing number of small satellite missions, particularly in the area of formation flight. Miniaturized Hall thrusters have been identified as a candidate ...

Warner, Noah Zachary, 1978-

2007-01-01T23:59:59.000Z

247

Building America Top Innovations Hall of Fame Profile - High...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Hall of Fame Profile - High-R Walls This Building America Innovations profile describes Building America research on high-R-value walls showing the difference between rated and...

248

History of Electrochemical Energy Consumption by Hall ... - TMS  

Science Conference Proceedings (OSTI)

Jan 1, 2007 ... (Hall) required more than 40 kWh / kg (18 kWh / lb) of aluminum produced and had current efficiencies ranging from 75 to 78 % . Today the best...

249

High-frequency Probing Diagnostic for Hall Current Plasma Thrusters  

DOE Green Energy (OSTI)

High-frequency oscillations (1-100 MHz) in Hall thrusters have apparently eluded significant experimental scrutiny. A diagnostic setup, consisting of a single Langmuir probe, a special shielded probe connector-positioner, and an electronic impedance-matching circuit, was successfully built and calibrated. Through simultaneous high-frequency probing of the Hall thruster plasma at multiple locations, high-frequency plasma waves have been identified and characterized for various thruster operating conditions.

A.A. Litvak; Y. Raitses; N.J. Fisch

2001-10-25T23:59:59.000Z

250

Electron mobility and effective mass in composite InGaAs quantum wells with InAs and GaAs nanoinserts  

Science Conference Proceedings (OSTI)

The paper is concerned with the theoretical and experimental studies of the band structure and electrical properties of InAlAs/InGaAs/InAlAs/InP heterostructures containing a composite InGaAs quantum well with InAs and GaAs nanoinserts. From the Shubnikov-de Haas effect, the effective cyclotron mass m{sub c}* is determined experimentally and calculated with consideration for the nonparabolicity of the electron energy spectrum. An approach to estimation of the effective mass is proposed and tested. The approach is based on weighted averaging of the m{sub c}* of the composite quantum well's constituent materials. A first proposed heterostructure containing two InAs inserts symmetrically arranged in the quantum well makes a 26% reduction in m{sub c}* compared to m{sub c}* in the lattice-matched In{sub 0.53}Ga{sub 0.47}As quantum well possible.

Ponomarev, D. S., E-mail: ponomarev_dmitr@mail.ru; Vasil'evskii, I. S. [National Nuclear Research University 'Moscow Engineering Physics Institute (MEPhI)' (Russian Federation); Galiev, G. B.; Klimov, E. A. [Russian Academy of Sciences, Institute of Ultrahigh-Frequency Semiconductor Electronics (Russian Federation); Khabibullin, R. A. [National Nuclear Research University 'Moscow Engineering Physics Institute (MEPhI)' (Russian Federation); Kulbachinskii, V. A.; Uzeeva, N. A. [Moscow State University (Russian Federation)

2012-04-15T23:59:59.000Z

251

Effect of heteroboundary spreading on the properties of exciton states in Zn(Cd)Se/ZnMgSSe quantum wells  

Science Conference Proceedings (OSTI)

Exciton states in Zn(Cd)Se/ZnMgSSe quantum wells with different diffusion spreading of interfaces are studied by optical spectroscopy methods. It is shown that the emission spectrum of quantum wells at low temperatures is determined by free excitons and bound excitons on neutral donors. The nonlinear dependence of the stationary photoluminescence intensity on the excitation power density and the biexponential luminescence decay are explained by the neutralization of charged defects upon photoexcitation of heterostructures. With the stationary illumination on, durable (about 40 min) reversible changes in the reflection coefficient near the exciton resonances of quantum wells are observed. It is shown that, along with the shift of exciton levels, the spreading of heteroboundaries leads to three effects: an increase in the excitonphonon interaction, an increase in the energy shift between the emission lines of free and bound excitons, and a decrease in the decay time of exciton luminescence in a broad temperature range. The main reasons for these effects are discussed.

Adiyatullin, A. F., E-mail: bert-sp@yandex.ru; Belykh, V. V.; Kozlovsky, V. I.; Krivobok, V. S., E-mail: krivobok@lebedev.ru; Martovitsky, V. P.; Nikolaev, S. N. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

2012-11-15T23:59:59.000Z

252

Quantum ring solitons and nonlocal effects in plasma wake field excitations  

Science Conference Proceedings (OSTI)

A theoretical investigation of the quantum transverse beam motion for a cold relativistic charged particle beam travelling in a cold, collisionless, strongly magnetized plasma is carried out. This is done by taking into account both the individual quantum nature of the beam particles (single-particle uncertainty relations and spin) and the self consistent interaction generated by the plasma wake field excitation. By adopting a fluid model of a strongly magnetized plasma, the analysis is carried out in the overdense regime (dilute beams) and in the long beam limit. It is shown that the quantum description of the collective transverse beam dynamics is provided by a pair of coupled nonlinear governing equations. It comprises a Poisson-like equation for the plasma wake potential (driven by the beam density) and a 2D spinorial Schroedinger equation for the wave function, whose squared modulus is proportional to the beam density, that is obtained in the Hartree's mean field approximation, after disregarding the exchange interactions. The analysis of this pair of equations, which in general exhibits a strong nonlocal character, is carried out analytically as well as numerically in both the linear and the nonlinear regimes, showing the existence of the quantum beam vortices in the form of Laguerre-Gauss modes and ring envelope solitons, respectively. In particular, when the relation between the plasma wake field response and the beam probability density is strictly local, the pair of the governing equations is reduced to the 2D Gross-Pitaevskii equation that allows one to establish the conditions for the self focusing and collapse. These conditions include the quantum nature of the beam particles. Finally, when the relation between the plasma wake field response and the beam probability density is moderately nonlocal, the above pair of equations permits to follow the spatio-temporal evolution of a quantum ring envelope soliton. Such a structure exhibits small or violent breathing, but it remains very stable for long time.

Fedele, R.; Tanjia, F. [Dipartimento di Scienze Fisiche, Universita di Napoli 'Federico II', and INFN, Napoli (Italy); De Nicola, S. [Dipartimento di Scienze Fisiche, Universita di Napoli 'Federico II', and INFN, Napoli (Italy); Istituto Nazionale di Ottica - C. N. R., Pozzuoli (Italy); Jovanovic, D. [Institute of Physics, University of Belgrade, Belgrade (Serbia); Shukla, P. K. [Center of Advanced Studies in Physical Sciences, Ruhr-Universitaet Bochum, Bochum (Germany)

2012-10-15T23:59:59.000Z

253

Effect of the nonlinear saturation of the gain on the peak modulation frequency in lasers based on self-assembled quantum dots  

SciTech Connect

Peak modulation frequency of lasers based on self-organized quantum dots is calculated taking into account the effect of nonlinear gain saturation. Because of a large nonlinear gain coefficient and a reduction in the differential gain with increasing optical losses, the peak modulation frequency is attained for an optimum loss level that is significantly lower than the saturated optical gain in the active region. For lasers based on multiply stacked arrays of quantum dots, the peak modulation frequency first increases with increasing number of quantum-dot layers before leveling off, with the limiting value being inversely proportional to the nonlinear gain coefficient.

Zhukov, A. E., E-mail: zhukov@beam.ioffe.ru; Arakcheeva, E. M. [Russian Academy of Sciences, St. Petersburg Academic University, Nanotechnology Research and Education Center (Russian Federation); Gordeev, N. Yu. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation); Zubov, F. I.; Kryzhanovskaya, N. V. [Russian Academy of Sciences, St. Petersburg Academic University, Nanotechnology Research and Education Center (Russian Federation); Maximov, M. V. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation); Savelyev, A. V. [Russian Academy of Sciences, St. Petersburg Academic University, Nanotechnology Research and Education Center (Russian Federation)

2011-07-15T23:59:59.000Z

254

Work extraction via quantum nondemolition measurements of qubits in cavities: Non-Markovian effects  

E-Print Network (OSTI)

We show that frequent nondemolition measurements of a quantum system immersed in a thermal bath allow the extraction of work in a closed cycle from the system-bath interaction (correlation) energy, a hitherto unexploited work resource. It allows for work even if no information is gathered or the bath is at zero temperature, provided the cycle is within the bath memory time. The predicted work resource may be the basis of quantum engines embedded in a bath with long memory time, such as the electromagnetic bath of a high-Q cavity coupled to two-level systems.

David Gelbwaser-Klimovsky; Noam Erez; Robert Alicki; Gershon Kurizki

2012-11-08T23:59:59.000Z

255

Quantum dynamics of an optical cavity coupled to a thin semitransparent membrane: Effect of membrane absorption  

Science Conference Proceedings (OSTI)

We study the quantum dynamics of the cavity optomechanical system formed by a Fabry-Perot cavity with a thin vibrating membrane at its center. We determine in particular to what extent optical absorption by the membrane hinders reaching a quantum regime for the cavity-membrane system. We show that even though membrane absorption may significantly lower the cavity finesse and also heat the membrane, one can still simultaneously achieve ground state cooling of a vibrational mode of the membrane and stationary optomechanical entanglement with state-of-the-art apparatuses.

Biancofiore, C.; Karuza, M.; Galassi, M.; Natali, R.; Vitali, D. [School of Science and Technology, Physics Division, University of Camerino, via Madonna delle Carceri, 9, I-62032 Camerino (Italy) and INFN, Sezione di Perugia (Italy); Tombesi, P.; Di Giuseppe, G. [School of Science and Technology, Physics Division, University of Camerino, via Madonna delle Carceri, 9, I-62032 Camerino (Italy) and INFN, Sezione di Perugia (Italy); CriptoCam S.r.l., via Madonna delle Carceri 9, I-62032 Camerino (Italy)

2011-09-15T23:59:59.000Z

256

Multiphoton Quantum Optics and Quantum State Engineering  

E-Print Network (OSTI)

We present a review of theoretical and experimental aspects of multiphoton quantum optics. Multiphoton processes occur and are important for many aspects of matter-radiation interactions that include the efficient ionization of atoms and molecules, and, more generally, atomic transition mechanisms; system-environment couplings and dissipative quantum dynamics; laser physics, optical parametric processes, and interferometry. A single review cannot account for all aspects of such an enormously vast subject. Here we choose to concentrate our attention on parametric processes in nonlinear media, with special emphasis on the engineering of nonclassical states of photons and atoms. We present a detailed analysis of the methods and techniques for the production of genuinely quantum multiphoton processes in nonlinear media, and the corresponding models of multiphoton effective interactions. We review existing proposals for the classification, engineering, and manipulation of nonclassical states, including Fock states, macroscopic superposition states, and multiphoton generalized coherent states. We introduce and discuss the structure of canonical multiphoton quantum optics and the associated one- and two-mode canonical multiphoton squeezed states. This framework provides a consistent multiphoton generalization of two-photon quantum optics and a consistent Hamiltonian description of multiphoton processes associated to higher-order nonlinearities. Finally, we discuss very recent advances that by combining linear and nonlinear optical devices allow to realize multiphoton entangled states of the electromnagnetic field, that are relevant for applications to efficient quantum computation, quantum teleportation, and related problems in quantum communication and information.

F. Dell'Anno; S. De Siena; F. Illuminati

2007-01-09T23:59:59.000Z

257

Quantum Institute  

NLE Websites -- All DOE Office Websites (Extended Search)

Quantum Institute Quantum Institute Quantum Institute A new research frontier awaits! Our door is open and we thrive on mutually beneficial partnerships, collaborations that drive innovations and new technologies. Contact Leader Malcolm Boshier (505) 665-8892 Email Two of LANL's most successful quantum technology initiatives: quantum cryptography and the race for quantum computer The area of quantum information, science, and technology is rapidly evolving, with important applications in the areas of quantum cryptography, quantum computing, quantum metrology, and advanced quantum-based sensors, some of which are directly relevant to the Laboratory's national security mission. Mission Foster a vigorous intellectual environment at LANL Define and develop strategic thrusts Target and pursue funding opportunities

258

Quantum physics meets biology  

E-Print Network (OSTI)

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

Markus Arndt; Thomas Juffmann; Vlatko Vedral

2009-11-01T23:59:59.000Z

259

Hall's Warehouse Corp Solar Project | Open Energy Information  

Open Energy Info (EERE)

Hall's Warehouse Corp Solar Project Hall's Warehouse Corp Solar Project Jump to: navigation, search Name Hall's Warehouse Corp Solar Project Facility Hall's Warehouse Corporation Solar Project Sector Solar Facility Type Thin Film (First Solar) and Amorphous Silicon Thin Film Laminate (UNI-SOLAR Laminates) Owner EnXco Developer EnXco Energy Purchaser Hall's Warehouse Corporation Address 501 Kentile Road Location South Plainfield, NJ Coordinates 40.5728254°, -74.4002111° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":40.5728254,"lon":-74.4002111,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

260

Jeans instability in a quantum dusty magnetoplasma  

SciTech Connect

Jeans instability in a homogeneous cold quantum dusty plasma in the presence of the ambient magnetic field and the quantum effect arising through the Bohm potential has been examined using the quantum magnetohydrodynamic model. It is found that the Jeans instability is significantly reduced by the presence of the dust-lower-hybrid wave and the ion quantum effect. The minimum wavenumber for Jeans stability depends clearly on ion quantum effect and the dust-lower-hybrid frequency also.

Salimullah, M. [Department of Physics, GC University, Lahore-54000 (Pakistan); Salam Chair in Physics, GC University, Lahore-54000 (Pakistan); Jamil, M.; Shah, H. A. [Department of Physics, GC University, Lahore-54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, GC University, Lahore-54000 (Pakistan)

2009-01-15T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Quantum motor and future  

E-Print Network (OSTI)

In a popular language, the possibilities of the Casimir expulsion effect are presented, which can be the basis of quantum motors. Such motors can be in the form of a special multilayer thin film with periodic and complex nanosized structures. Quantum motors of the type of the Casimir platforms can be the base of transportation, energy and many other systems in the future.

Evgeny G. Fateev

2013-01-20T23:59:59.000Z

262

Quantum motor and future  

E-Print Network (OSTI)

In a popular language, the possibilities of the Casimir expulsion effect are presented, which can be the basis of quantum motors. Such motors can be in the form of a special multilayer thin film with periodic and complex nanosized structures. Quantum motors of the type of the Casimir platforms can be the base of transportation, energy and many other systems in the future.

Fateev, Evgeny G

2013-01-01T23:59:59.000Z

263

Quantum Dots: Theory  

SciTech Connect

This review covers the description of the methodologies typically used for the calculation of the electronic structure of self-assembled and colloidal quantum dots. These are illustrated by the results of their application to a selected set of physical effects in quantum dots.

Vukmirovic, Nenad; Wang, Lin-Wang

2009-11-10T23:59:59.000Z

264

Quantum Gravity: Has Spacetime Quantum Properties?  

E-Print Network (OSTI)

The incompatibility between GR and QM is generally seen as a sufficient motivation for the development of a theory of Quantum Gravity. If - so a typical argumentation - QM gives a universally valid basis for the description of all natural systems, then the gravitational field should have quantum properties. Together with the arguments against semi-classical theories of gravity, this leads to a strategy which takes a quantization of GR as the natural avenue to Quantum Gravity. And a quantization of the gravitational field would in some sense correspond to a quantization of geometry. Spacetime would have quantum properties. But, this strategy will only be successful, if gravity is a fundamental interaction. - What, if gravity is instead an intrinsically classical phenomenon? Then, if QM is nevertheless fundamentally valid, gravity can not be a fundamental interaction. An intrinsically classical gravity in a quantum world would have to be an emergent, induced or residual, macroscopic effect, caused by other interactions. The gravitational field (as well as spacetime) would not have any quantum properties. A quantization of GR would lead to artifacts without any relation to nature. The serious problems of all approaches to Quantum Gravity that start from a direct quantization of GR or try to capture the quantum properties of gravity in form of a 'graviton' dynamics - together with the, meanwhile, rich spectrum of approaches to an emergent gravity and/or spacetime - make this latter option more and more interesting for the development of a theory of Quantum Gravity. The most advanced emergent gravity (and spacetime) scenarios are of an information-theoretical, quantum-computational type.

Reiner Hedrich

2009-02-02T23:59:59.000Z

265

A Proposed Alternative Low Energy Quantum Field Theory of Gravity Based on a Bose-Einstein Condensate Effect  

E-Print Network (OSTI)

An alternative quantum field theory for gravity is proposed for low energies based on an attractive effect between contaminants in a Bose-Einstein Condensate rather than on particle exchange. In the ``contaminant in condensate effect," contaminants cause a potential in an otherwise uniform condensate, forcing the condensate between two contaminants to a higher energy state. The energy of the system decreases as the contaminants come closer together, causing an attractive force between contaminants. It is proposed that mass-energy may have a similar effect on Einstein's space-time field, and gravity is quantized by the same method by which the contaminant in condensate effect is quantized. The resulting theory is finite and, if a physical condensate is assumed to underly the system, predictive. However, the proposed theory has several flaws at high energies and is thus limited to low energies. Falsifiable predictions are given for the case that the Higgs condensate is assumed to be the condensate underlying gravity.

Alexander Oshmyansky

2007-03-08T23:59:59.000Z

266

Town Hall Meeting #3: Green Button | OpenEI Community  

Open Energy Info (EERE)

Town Hall Meeting #3: Green Button Town Hall Meeting #3: Green Button Home > Groups > OpenEI Community Central Graham7781's picture Submitted by Graham7781(2002) Super contributor 5 June, 2012 - 14:40 imported OpenEI OpenEI would like to thank all those that have participated in the Town Hall Forum thus far. We have been pleased to hear the questions and learn more about how our users leverage OpenEI, and what specifically they would like more of out of the platform. This coming week we'd like to focus on the Green Button Initiative and Green Button data/apps. You can use this time to talk to OpenEI about the Green Button, where the future of Green Button data is headed, where to find information on OpenEI about the Green Button, and what we are doing to provide Green Button data and apps.

267

Reconnection events in two-dimensional Hall magnetohydrodynamic turbulence  

Science Conference Proceedings (OSTI)

The statistical study of magnetic reconnection events in two-dimensional turbulence has been performed by comparing numerical simulations of magnetohydrodynamics (MHD) and Hall magnetohydrodynamics (HMHD). The analysis reveals that the Hall term plays an important role in turbulence, in which magnetic islands simultaneously reconnect in a complex way. In particular, an increase of the Hall parameter, the ratio of ion skin depth to system size, broadens the distribution of reconnection rates relative to the MHD case. Moreover, in HMHD the local geometry of the reconnection region changes, manifesting bifurcated current sheets and quadrupolar magnetic field structures in analogy to laminar studies, leading locally to faster reconnection processes in this case of reconnection embedded in turbulence. This study supports the idea that the global rate of energy dissipation is controlled by the large scale turbulence, but suggests that the distribution of the reconnection rates within the turbulent system is sensitive to the microphysics at the reconnection sites.

Donato, S.; Servidio, S.; Carbone, V. [Dipartimento di Fisica, Universita della Calabria, I-87036 Cosenza (Italy); Dmitruk, P. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Fisica de Buenos Aires, CONICET, Buenos Aires (Argentina); Shay, M. A.; Matthaeus, W. H. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States); Cassak, P. A. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

2012-09-15T23:59:59.000Z

268

The DVCS program in Hall A at Jefferson Lab  

Science Conference Proceedings (OSTI)

The DVCS Hall A/JLab experiments aim at providing data relevant to the '3-D structure of the nucleon' exploration by measuring precise absolute cross sections in the Deep Exclusive domain. Deeply Virtual Compton Scattering off the nucleon is the simplest process which is sensitive to the Generalized Parton Distribution functions. Currently, the DVCS in Hall A program is articulated in three steps. The first generation of experiments showed the power of precise measurement of absolute cross sections to test factorization of the DVCS amplitude. The second generation of experiments (data under analysis) will separate (at twist-2 order) all of the terms making up the unpolarized cross section. And the third generation of experiments (data to be taken with the 12 GeV beam at JLab) will provide measurements over an extended kinematic range. In this conference proceeding, the status of the DVCS in Hall A/JLab program is reviewed.

Julie Roche

2012-09-01T23:59:59.000Z

269

Effect of gate-driven spin resonance on the conductance of a one-dimensional quantum wire  

E-Print Network (OSTI)

We consider quasiballistic electron transmission in a one-dimensional quantum wire subject to both time-independent and periodic potentials of a finger gate that results in a coordinate- and time-dependent Rashba-type spin-orbit coupling. A spin-dependent conductance is calculated as a function of external constant magnetic field, the electric field frequency, and the potential strength. The results demonstrate the effect of the gate-driven electric dipole spin resonance in a transport phenomenon such as spin-flip electron transmission.

Almas F. Sadreev; E. Ya. Sherman

2013-10-10T23:59:59.000Z

270

Variable operation of Hall thruster with multiple segmented electrodes  

DOE Green Energy (OSTI)

Variable plasma jet velocity with low beam divergence over a range of mass flow rates can be achieved through segmented electrode operation of Hall plasma accelerator. With the use of just a cathode side electrode at the cathode potential, the beam divergence can be decreased substantially, at some cost in efficiency. However, the additional use of an anode side electrode retains the same reduced plume divergence, but at efficiencies comparable to the non-segmented operation. The high efficiency persists also when the anode side electrode is biased at an intermediate potential, thus producing two-stage Hall accelerator operation.

Fisch, N.J.; Raitses, Y.; Dorf, L.A.; Litvak, A.A.

2000-02-07T23:59:59.000Z

271

An edition of Hall Caine's The Demon Lover  

E-Print Network (OSTI)

Hall Caine, once a popular writer, is now forgotten. This is the first edition of Hall Caine's play The Demon Lover. The text is based on the only known typescript of the play which is corrected in the author's own hand and which was bound for Caine's personal library at Greeba Castle. The edition is presented as a clear text with accompanying apparatus and a contextualization of the play and Caine. The demon lover motif is traced through literary history and the intertextuality of his work and other notables such as Edgar Allan Poe is discussed.

Linnstaedter, Joan

1993-01-01T23:59:59.000Z

272

Electron Hall Mobility in GaAsBi  

Science Conference Proceedings (OSTI)

We present measurements of the electron Hall mobility in n-type GaAs{sub 1-x}Bi{sub x} epilayers. We observed no significant degradation in the electron mobility with Bi incorporation in GaAs, up to a concentration of 1.2%. At higher Bi concentration ({ge} 1.6%) some degradation of the electron mobility was observed, although there is no apparent trend. Temperature dependent Hall measurements of the electron mobility suggest neutral impurity scattering to be the dominant scattering mechanism.

Kini, R. N.; Bhusal, L.; Ptak, A. J.; France, R.; Mascarenhas, A.

2009-01-01T23:59:59.000Z

273

Effects of thermal and quantum fluctuations on the phase diagram of a spin-1 {sup 87}Rb Bose-Einstein condensate  

Science Conference Proceedings (OSTI)

We investigate the effects of thermal and quantum fluctuations on the phase diagram of a spin-1 {sup 87}Rb Bose-Einstein condensate (BEC) under the quadratic Zeeman effect. Due to the large ratio of spin-independent to spin-dependent interactions of {sup 87}Rb atoms, the effect of noncondensed atoms on the condensate is much more significant than that in scalar BECs. We find that the condensate and spontaneous magnetization emerge at different temperatures when the ground state is in the broken-axisymmetry phase. In this phase, a magnetized condensate induces spin coherence of noncondensed atoms in different magnetic sublevels, resulting in temperature-dependent magnetization of the noncondensate. We also examine the effect of quantum fluctuations on the order parameter at absolute zero and find that the ground-state phase diagram is significantly altered by quantum depletion.

Phuc, Nguyen Thanh; Kawaguchi, Yuki [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Ueda, Masahito [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); ERATO Macroscopic Quantum Control Project, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

2011-10-15T23:59:59.000Z

274

Effect of imperfect Faraday mirrors on security of a Faraday-Michelson quantum cryptography system  

E-Print Network (OSTI)

The one-way Faraday-Michelson system is a very useful practical quantum cryptography system where Faraday mirrors(FMs) play an important role. In this paper we analyze the security of this system against imperfect FMs. We consider the security loophole caused by the imperfect FMs in Alice's and Bob's security zones. Then we implement a passive Faraday mirror attack in this system. By changing the values of the imperfection parameters of Alice's FMs, we calculate the quantum bit error rate between Alice and Bob induced by Eve and the probability that Eve obtains outcomes successfully. It is shown that the imperfection of one of Alice's two FMs makes the system sensitive to the attack. At last we give a modified key rate as a function of the Faraday mirror imperfections. The security analysis indicates that both Alice's and Bob's imperfect FMs can compromise the secure key.

Wang Weilong; Gao Ming; Ma Zhi

2013-10-29T23:59:59.000Z

275

Correlation, relativistic, and quantum electrodynamics effects on the atomic structure of eka-thorium  

Science Conference Proceedings (OSTI)

Large-scale multiconfiguration Dirac-Fock calculations have been performed for the superheavy element eka-thorium, Z=122. The resulting atomic structure is compared with that obtained by various computational approaches involving different degrees of approximation in order to elucidate the role that correlation, relativistic, Breit, and quantum electrodynamics corrections play in determining the low-energy atomic spectrum. The accuracy of the calculations is assessed by comparing theoretical results obtained for thorium with available experimental data.

Gaigalas, Gediminas; Gaidamauskas, Erikas; Rudzikas, Zenonas; Magnani, Nicola; Caciuffo, Roberto [Vilnius University Research Institute of Theoretical Physics and Astronomy, A. Gostauto 12, LT-01108 Vilnius (Lithuania); European Commission, Joint Research Centre, Institute for Transuranium Elements, Postfach 2340, D-76125 Karlsruhe (Germany)

2010-02-15T23:59:59.000Z

276

Beable-Guided Quantum Theories: Generalising Quantum Probability Laws  

E-Print Network (OSTI)

We introduce the idea of a {\\it beable-guided quantum theory}. Beable-guided quantum theories (BGQT) are generalisations of quantum theory, inspired by Bell's concept of beables. They modify the quantum probabilities for some specified set of fundamental events, histories, or other elements of quasiclassical reality by probability laws that depend on the realised configuration of beables. For example, they may define an additional probability weight factor for a beable configuration, independent of the quantum dynamics. BGQT can be fitted to observational data to provide foils against which to compare explanations based on standard quantum theory. For example, a BGQT could, in principle, characterise the effects attributed to dark energy or dark matter, or any other deviation from the predictions of standard quantum dynamics, without introducing extra fields or a cosmological constant. The complexity of the beable-guided theory would then parametrise how far we are from a standard quantum explanation. Less co...

Kent, Adrian

2013-01-01T23:59:59.000Z

277

HIGH ACCURACY BEAM CURRENT MONITOR SYSTEM FOR CEBAF'S EXPERIMENTAL HALL A *  

E-Print Network (OSTI)

HIGH ACCURACY BEAM CURRENT MONITOR SYSTEM FOR CEBAF'S EXPERIMENTAL HALL A * J.-C. Denard , A. Saha CEBAF accelerator delivers continuous wave (CW) electron beams to three experimental Halls. In Hall A is described. 1 INTRODUCTION The CEBAF accelerator delivers continuous wave (CW) electron beams to three

278

Quantum Thermodynamics  

E-Print Network (OSTI)

Quantum thermodynamics addresses the emergence of thermodynamical laws from quantum mechanics. The link is based on the intimate connection of quantum thermodynamics with the theory of open quantum systems. Quantum mechanics inserts dynamics into thermodynamics giving a sound foundation to finite-time-thermodynamics. The emergence of the 0-law I-law II-law and III-law of thermodynamics from quantum considerations is presented. The emphasis is on consistence between the two theories which address the same subject from different foundations. We claim that inconsistency is the result of faulty analysis pointing to flaws in approximations.

Ronnie Kosloff

2013-05-10T23:59:59.000Z

279

Millard W. Hall, Director Volume 10, Number 4  

E-Print Network (OSTI)

following exposure to the stress. Water use efficiency in terms of grain produced per unit of water used may in 991 kg grain produced per k-liter water used, compared to 888 kg grain produced by unstressed controlsMillard W. Hall, Director Volume 10, Number 4 GUEST EDITORIAL State Water Planning Process

Nebraska-Lincoln, University of

280

143 Caldwell Hall Ithaca, NY 14853-2602  

E-Print Network (OSTI)

a conference in Washington, D.C., may receive $225). Awards will not, under any circumstances, exceed $675 Manitoba 335 Ontario (Toronto, Ottawa) 335 Quebec (Montreal) 235 Central & South America 675 Washington, DC will need to be picked up at the cashier's window in 260 Day Hall. If a student does not attend

Keinan, Alon

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

143 Caldwell Hall Ithaca, NY 14853-2602  

E-Print Network (OSTI)

in Washington, D.C., may receive $225). Awards will not, under any circumstances, exceed $675. The Graduate Manitoba 335 Ontario (Toronto, Ottawa) 335 Quebec (Montreal) 235 Central & South America 675 Washington, DC up at the cashier's window in 260 Day Hall. If a student does not attend the conference, s/he should

Walter, M.Todd

282

Security Metrology and the Monty Hall Problem Bennet S. Yee  

E-Print Network (OSTI)

Security Metrology and the Monty Hall Problem Bennet S. Yee April 2, 2001 Abstract Evaluating computing systems and classifying them by the security properties they provide is not new [13, 14]. Other researchers [8, 9] have pointed out the difficulty of evaluating security and the apparent binary nature

Yee, Bennet

283

Security Metrology and the Monty Hall Problem Bennet S. Yee  

E-Print Network (OSTI)

Security Metrology and the Monty Hall Problem Bennet S. Yee April 2, 2001 Abstract Evaluating computing systems and classifying them by the security properties they provide is not new [13, 14]. Other researchers [8, 9] have pointed out the di?culty of evaluating security and the apparent binary nature

Yee, Bennet

284

Nonlinear Quantum Gravity  

E-Print Network (OSTI)

Nonlinear quantum mechanics at the Planck scale can produce nonlocal effects contributing to resolution of singularities, to cosmic acceleration, and modified black-hole dynamics, while avoiding the usual causality issues.

George Svetlichny

2006-02-01T23:59:59.000Z

285

Relativistic Quantum Metrology: Exploiting relativity to improve quantum measurement technologies  

E-Print Network (OSTI)

We present a framework for relativistic quantum metrology that is useful for both Earth-based and space-based technologies. Quantum metrology has been so far successfully applied to design precision instruments such as clocks and sensors which outperform classical devices by exploiting quantum properties. There are advanced plans to implement these and other quantum technologies in space, for instance Space-QUEST and Space Optical Clock projects intend to implement quantum communications and quantum clocks at regimes where relativity starts to kick in. However, typical setups do not take into account the effects of relativity on quantum properties. To include and exploit these effects, we introduce techniques for the application of metrology to quantum field theory (QFT). QFT properly incorporates quantum theory and relativity, in particular, at regimes where space-based experiments take place. This framework allows for high precision estimation of parameters that appear in QFT including proper times and accelerations. Indeed, the techniques can be applied to develop a novel generation of relativistic quantum technologies for gravimeters, clocks and sensors. As an example, we present a high precision device which improves the state-of-the-art in quantum accelerometers by exploiting relativistic effects.

Mehdi Ahmadi; David Edward Bruschi; Nicolai Friis; Carlos Sabn; Gerardo Adesso; Ivette Fuentes

2013-07-26T23:59:59.000Z

286

Multiphoton Quantum Optics and Quantum State Engineering  

E-Print Network (OSTI)

We present a review of theoretical and experimental aspects of multiphoton quantum optics. Multiphoton processes occur and are important for many aspects of matter-radiation interactions that include the efficient ionization of atoms and molecules, and, more generally, atomic transition mechanisms; system-environment couplings and dissipative quantum dynamics; laser physics, optical parametric processes, and interferometry. A single review cannot account for all aspects of such an enormously vast subject. Here we choose to concentrate our attention on parametric processes in nonlinear media, with special emphasis on the engineering of nonclassical states of photons and atoms that are relevant for the conceptual investigations as well as for the practical applications of forefront aspects of modern quantum mechanics. We present a detailed analysis of the methods and techniques for the production of genuinely quantum multiphoton processes in nonlinear media, and the corresponding models of multiphoton effective interactions. We review existing proposals for the classification, engineering, and manipulation of nonclassical

Silvio De Siena; Fabrizio Illuminati

2007-01-01T23:59:59.000Z

287

Buckled nano rod - a two state system: quantum effects on its dynamics  

E-Print Network (OSTI)

We consider a suspended elastic rod under longitudinal compression. The compression can be used to adjust potential energy for transverse displacements from harmonic to double well regime. The two minima in potential energy curve describe two possible buckled states. Using transition state theory (TST) we have calculated the rate of conversion from one state to other. If the strain $\\epsilon = 4 \\epsilon_c$ the simple TST rate diverges. We suggest a method to correct this divergence for quantum calculations. We also find that zero point energy contributions can be quite large so that single mode calculations can lead to large errors in the rate.

Chakraborty, Aniruddha

2011-01-01T23:59:59.000Z

288

Buckled nano rod - a two state system: quantum effects on its dynamics  

E-Print Network (OSTI)

We consider a suspended elastic rod under longitudinal compression. The compression can be used to adjust potential energy for transverse displacements from harmonic to double well regime. The two minima in potential energy curve describe two possible buckled states. Using transition state theory (TST) we have calculated the rate of conversion from one state to other. If the strain $\\epsilon = 4 \\epsilon_c$ the simple TST rate diverges. We suggest a method to correct this divergence for quantum calculations. We also find that zero point energy contributions can be quite large so that single mode calculations can lead to large errors in the rate.

Aniruddha Chakraborty

2011-07-18T23:59:59.000Z

289

Isotope effect on adsorbed quantum phases: Diffusion of H2 and D2 in nanoporous carbon  

SciTech Connect

Quasielastic neutron scattering of H2 and D2 in a nanoporous carbon at 10 40 K demonstrates extreme quantum sieving, with D2 diffusing up to 76 times faster. D2 also shows liquid-like diffusion, while H2 exhibits distinct solid-type diffusion. The onset of diffusion occurs at 22 25 K for H2 and 10 13 K for D2. We show this difference may be explained by different commensurability of the two adsorbed isotopes with carbon substrate. We further observe that H2 and D2 have identical thermal de Broglie wavelength at their respective onset temperatures, and correlated with the dominant pore size.

Contescu, Cristian I [ORNL; Zhang, Hongxin [ORNL; Olsen, Raina J [ORNL; Mamontov, Eugene [ORNL; Morris, James R [ORNL; Gallego, Nidia C [ORNL

2013-01-01T23:59:59.000Z

290

Quantum Histories and Quantum Gravity  

E-Print Network (OSTI)

This paper reviews the histories approach to quantum mechanics. This discussion is then applied to theories of quantum gravity. It is argued that some of the quantum histories must approximate (in a suitable sense) to classical histories, if the correct classical regime is to be recovered. This observation has significance for the formulation of new theories (such as quantum gravity theories) as it puts a constraint on the kinematics, if the quantum/classical correspondence principle is to be preserved. Consequences for quantum gravity, particularly for Lorentz symmetry and the idea of "emergent geometry", are discussed.

Joe Henson

2009-01-26T23:59:59.000Z

291

Studies of Novel Quantum Phenomena in Ruthenates  

SciTech Connect

Strongly correlated oxides have been the subject of intense study in contemporary condensed matter physics, and perovskite ruthenates (Sr,Ca)n+1RunO3n+1 have become a new focus in this field. One of important characteristics of ruthenates is that both lattice and orbital degrees of freedom are active and are strongly coupled to charge and spin degrees of freedom. Such a complex interplay of multiple degrees of freedom causes the properties of ruthenates to exhibit a gigantic response to external stimuli under certain circumstances. Magnetic field, pressure, and chemical composition all have been demonstrated to be effective in inducing electronic/magnetic phase transitions in ruthenates. Therefore, ruthenates are ideal candidates for searching for novel quantum phenomena through controlling external parameters. The objective of this project is to search for novel quantum phenomena in ruthenate materials using high-quality single crystals grown by the floating-zone technique, and investigate the underlying physics. The following summarizes our accomplishments. We have focused on trilayered Sr4Ru3O10 and bilayered (Ca1-xSrx)3Ru2O7. We have succeeded in growing high-quality single crystals of these materials using the floating-zone technique and performed systematic studies on their electronic and magnetic properties through a variety of measurements, including resistivity, Hall coefficient, angle-resolved magnetoresistivity, Hall probe microscopy, and specific heat. We have also studied microscopic magnetic properties for some of these materials using neutron scattering in collaboration with Los Alamos National Laboratory. We have observed a number of unusual exotic quantum phenomena through these studies, such as an orbital selective metamagnetic transition, bulk spin valve effect, and a heavy-mass nearly ferromagnetic state with a surprisingly large Wilson ratio. Our work has also revealed underlying physics of these exotic phenomena. Exotic phenomena of correlated electron has been among central topics of contempary condensed matter physics. Ultrfast phase transitions accompanied by switching of conductivity or magnetization in stronly correlated materials are believed to be promising in developing next generation of transistors. Our work on layered ruthenates has remarkably advanced our understanding of how the exotic phenomena of correlated electrons is governed by the complex interplay between charge, spin, lattice and orbital degrees of freedom. In addition to studies on ruthenates, we have also expanded our research to the emerging field of Fe-based superconductors, focusing on the iron chalcogenide Fe1+y(Te1-xSex) superconductor system. We first studied the superconductivity of this alloy system following the discovery of superconductivity in FeSe using polycrystalline samples. Later, we successfuly grew high-quality single crystals of these materials. Using these single crystals, we have determined the magnetic structure of the parent compound Fe1+yTe, observed spin resonance of superconducting state in optimally doped samples, and established a phase diagram. Our work has produced an important impact in this burgeoning field. The PI presented an invited talk on this topic at APS March meeting in 2010. We have published 19 papers in these two areas (one in Nature materials, five in Physical Review Letters, and nine in Physical Review B) and submitted two (see the list of publications attached below).

Mao, Zhiqiang

2011-04-08T23:59:59.000Z

292

Advancing the Hall Heroult Electrolytic Process  

Science Conference Proceedings (OSTI)

These secondary processes, including reactions associated with impurities and anodes consumption, those leading to onset of anode effect, and alumina...

293

Effect of electron-nuclear spin interactions on electron-spin qubits localized in self-assembled quantum dots  

E-Print Network (OSTI)

The effect of electron-nuclear spin interactions on qubit operations is investigated for a qubit represented by the spin of an electron localized in a self-assembled quantum dot. The localized electron wave function is evaluated within the atomistic tight-binding model. The magnetic field generated by the nuclear spins is estimated in the presence of an inhomogeneous environment characterized by a random nuclear spin configuration, by the dot-size distribution, by alloy disorder, and by interface disorder. Due to these inhomogeneities, the magnitude of the nuclear magnetic field varies from one qubit to another by the order of 100 G, 100 G, 10 G, and 0.1 G, respectively. The fluctuation of the magnetic field causes errors in exchange operations due to the inequality of the Zeeman splitting between two qubits. We show that the errors can be made lower than the quantum error threshold if an exchange energy larger than 0.1 meV is used for the operation.

Seungwon Lee; Paul von Allmen; Fabiano Oyafuso; Gerhard Klimeck; K. Birgitta Whaley

2004-03-17T23:59:59.000Z

294

Photoinduced Surface Oxidation and Its Effect on the Exciton Dynamics of CdSe Quantum Dots  

DOE Green Energy (OSTI)

With increased interest in semiconductor nanoparticles for use in quantum dot solar cells there comes a need to understand the long-term photostability of such materials. Colloidal CdSe quantum dots (QDs) were suspended in toluene and stored in combinations of light/dark and N{sub 2}/O{sub 2} to simulate four possible benchtop storage environments. CdSe QDs stored in a dark, oxygen-free environment were observed to better retain their optical properties over the course of 90 days. The excited state lifetimes, determined through femtosecond transient absorption spectroscopy, of air-equilibrated samples exposed to light exhibit a decrease in average lifetime (0.81 ns) when compared to samples stored in a nitrogen/dark environment (8.3 ns). A photoetching technique commonly used for controlled reduction of QD size was found to induce energetic trap states to CdSe QDs and accelerate the rate of electron-hole recombination. X-ray absorption near edge structure (XANES) analysis confirms surface oxidation, the extent of which is shown to be dependent on the thickness of the ligand shell.

Hines, Douglas A.; Becker, Matthew A.; Kamat, Prashant V. (Notre)

2012-11-14T23:59:59.000Z

295

Quantum Chromodynamics  

E-Print Network (OSTI)

Quantum chromodynamics is the quantum gauge field theory that describes the strong interactions. This article reviews the basic structure, successes and challenges of quantum chromodynamics as it manifests itself at short and long distances, including the concepts of asymptotic freedom, confinement and infrared safety.

George Sterman

2005-12-27T23:59:59.000Z

296

TBB-0042 - In the Matter of Curtis Hall | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

42 - In the Matter of Curtis Hall 42 - In the Matter of Curtis Hall TBB-0042 - In the Matter of Curtis Hall This letter concerns the complaint of retaliation filed by Curtis Hall (the complainant or Mr. Hall) with the Department of Energy under 10 C . F. R. Part 7 0 8 , the DOE Con tractor Employee (Whistleblower) Protection Program. On March 13, 2008, the Office of Hearings and Appeals (OHA) received your Petition for Secretarial Review of the appeal decision we issued on February 13, 2008. Under Part 708 regulations, the Secretary will reverse or revise an appeal decision by the Director of OHA only in extraordinary circumstances. 10 C.F.R. § 708.35(d). tbb0042.pdf More Documents & Publications TBA-0042 - In the Matter of Curtis Hall TBB-0030 - In the Matter of Curtis Broaddus TBH-0042 - In the Matter of Curtis Hall

297

VEE-0067 - In the Matter of M.L. Halle Oil Service, Inc. | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

67 - In the Matter of M.L. Halle Oil Service, Inc. 67 - In the Matter of M.L. Halle Oil Service, Inc. VEE-0067 - In the Matter of M.L. Halle Oil Service, Inc. On August 9, 1999 M.L. Halle Oil Service, Inc. (Halle) of Manchester, New Hampshire, filed an Application for Exception with the Office of Hearings and Appeals (OHA) of the Department of Energy (DOE). In its application, Halle requests that it be temporarily relieved of the requirement to prepare and file the Energy Information Administration's (EIA) form entitled "Resellers'/ Retailers' Monthly Petroleum Product Sales Report" (Form EIA-782B). As explained below, we have concluded that Halle shall be excused from filing Form EIA-782B for four months. vee0067.pdf More Documents & Publications VEE-0080 - In the Matter of Potter Oil Co., Inc.

298

Quantum Information Portal  

Science Conference Proceedings (OSTI)

... Quantum Devices; Quantum Information Technology; Quantum Key Distribution; ... Entangled photon generation in a phase-modulated, quasi ...

2013-10-23T23:59:59.000Z

299

Quantum bundles and quantum interactions  

E-Print Network (OSTI)

A geometric framework for describing quantum particles on a possibly curved background is proposed. Natural constructions on certain distributional bundles (`quantum bundles') over the spacetime manifold yield a quantum ``formalism'' along any 1-dimensional timelike submanifold (a `detector'); in the flat, inertial case this turns out to reproduce the basic results of the usual quantum field theory, while in general it could be seen as a local, ``linearized'' description of the actual physics.

Daniel Canarutto

2005-06-22T23:59:59.000Z

300

Quantum Cosmology  

E-Print Network (OSTI)

We give an introduction into quantum cosmology with emphasis on its conceptual parts. After a general motivation we review the formalism of canonical quantum gravity on which discussions of quantum cosmology are usually based. We then present the minisuperspace Wheeler--DeWitt equation and elaborate on the problem of time, the imposition of boundary conditions, the semiclassical approximation, the origin of irreversibility, and singularity avoidance. Restriction is made to quantum geometrodynamics; loop quantum gravity and string theory are discussed in other contributions to this volume.

Claus Kiefer; Barbara Sandhoefer

2008-04-04T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Si/SiGe Quantum Devices and Quantum Wells: Electron Spin Coherence  

E-Print Network (OSTI)

Si/SiGe Quantum Devices and Quantum Wells: Electron Spin Coherence J. L. Truitt1 , K. A. Slinker1 quantum wells are clad by SiGe barriers, and therefore intrinsically strained, leading to growth the current status of ESR experiments in Si/SiGe quantum wells. Many factors can effect transport in silicon

Sheridan, Jennifer

302

Coupled-channels density-matrix approach to low-energy nuclear collision dynamics: A technique for quantifying quantum decoherence effects on reaction observables  

E-Print Network (OSTI)

The coupled-channels density-matrix technique for nuclear reaction dynamics, which is based on the Liouville-von Neumann equation with Lindblad dissipative terms, is developed with the inclusion of full angular momentum couplings. It allows a quantitative study of the role and importance of quantum decoherence in nuclear scattering. Formulae of asymptotic observables that can reveal effects of quantum decoherence are given. A method for extracting energy-resolved scattering information from the time-dependent density matrix is introduced. As an example, model calculations are carried out for the low-energy collision of the $^{16}$O projectile on the $^{154}$Sm target.

Alexis Diaz-Torres

2010-10-18T23:59:59.000Z

303

Calder Hall Cooling Tower Demolition: Landmark Milestone for Decommissioning at Sellafield  

Science Conference Proceedings (OSTI)

September 2007 saw a very visible change to the Sellafield site following the culmination of a major decommissioning project; the demolition of the four Calder Hall cooling towers. A key part of the UK's nuclear industrial heritage, Calder Hall, the world's first commercial nuclear power station, was opened by Her Majesty Queen Elizabeth II in October 1953 and continued to generate electricity until its closure in 2003. Following the decision to decommission the Calder Hall site, explosive demolition was identified as the safest and most cost effective route for the removal of the towers. The technique, involving the placement of explosive in 60% of the circumference of both shell and legs, is a tried and tested method which had already been used successfully in more than 200 cooling towers in the UK in the last 30 years. The location and composition of the four 88 metre high towers also created additional challenges. Situated only 40 metres away from the UK's only nuclear Fuel Handling Plant, as well as other sensitive structures on the Sellafield site, the project had to address the impact of a number of key areas, including dust, ground vibration and air over pressure, to ensure that the demolition could be carried out safely and without significant impact on other operational areas on the site. At the same time, the towers had to be prepared for demolition in a way that minimised the amounts of radioactive or hazardous waste materials arising. This paper follows the four year journey from the initial decision to demolish the towers right through to the demolition itself as well as the clean up of the site post demolition. It will also consider the massive programme of work necessary not only to carry out the physical work safely but also to gain regulatory confidence and stakeholder support to carry out the project successfully. In summary: The demolition of the four Calder Hall cooling towers was a highly visible symbol of the changes that are occurring on the Sellafield site as it moves forward towards a decommissioning future. Although in itself the demolition was both straightforward and standard, the various complexities posed by the towers situation at Sellafield introduced an entirely new element to the project, with a number of complex challenges which had to be overcome or resolved before the demolition could take place. It is a testament to the skill and dedication of the project team and its associated contractors that the project was delivered safely and successfully without a single accident, injury or event throughout the entire four years, and with minimal impact on both site operations and the local community. (authors)

Williamson, E.J. [Nuclear Decommissioning and Major Projects Group, Sellafield Ltd, Seascale, Cumbria (United Kingdom)

2008-07-01T23:59:59.000Z

304

Quantum polar codes for arbitrary channels  

E-Print Network (OSTI)

We construct a new entanglement-assisted quantum polar coding scheme which achieves the symmetric coherent information rate by synthesizing "amplitude" and "phase" channels from a given, arbitrary quantum channel. We first demonstrate the coding scheme for arbitrary quantum channels with qubit inputs, and we show that quantum data can be reliably decoded by O(N) rounds of coherent quantum successive cancellation, followed by N controlled-NOT gates (where N is the number of channel uses). We also find that the entanglement consumption rate of the code vanishes for degradable quantum channels. Finally, we extend the coding scheme to channels with multiple qubit inputs. This gives a near-explicit method for realizing one of the most striking phenomena in quantum information theory: the superactivation effect, whereby two quantum channels which individually have zero quantum capacity can have a non-zero quantum capacity when used together.

Wilde, Mark M

2012-01-01T23:59:59.000Z

305

Centre Hall, Pennsylvania: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

Hall, Pennsylvania: Energy Resources Hall, Pennsylvania: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 40.8475635°, -77.6861093° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":40.8475635,"lon":-77.6861093,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

306

Self-Consistent C-V Characterization of Depletion Mode Buried Channel InGaAs/InAs Quantum Well FET Incorporating Strain Effects  

E-Print Network (OSTI)

We investigated Capacitance-Voltage (C-V) characteristics of the Depletion Mode Buried Channel InGaAs/InAs Quantum Well FET by using Self-Consistent method incorporating Quantum Mechanical (QM) effects. Though the experimental results of C-V for enhancement type device is available in recent literature, a complete characterization of electrostatic property of depletion type Buried Channel Quantum Well FET (QWFET) structure is yet to be done. C-V characteristics of the device is studied with the variation of three important process parameters: Indium (In) composition, gate dielectric and oxide thickness. We observed that inversion capacitance and ballistic current tend to increase with the increase in Indium (In) content in InGaAs barrier layer.

Imtiaz Ahmed; Iftikhar Ahmad Niaz; Md. Hasibul Alam; Nadim Chowdhury; Zubair Al Azim; Quazi Deen Mohd Khosru

2012-11-16T23:59:59.000Z

307

Self-Consistent C-V Characterization of Depletion Mode Buried Channel InGaAs/InAs Quantum Well FET Incorporating Strain Effects  

E-Print Network (OSTI)

We investigated Capacitance-Voltage (C-V) characteristics of the Depletion Mode Buried Channel InGaAs/InAs Quantum Well FET by using Self-Consistent method incorporating Quantum Mechanical (QM) effects. Though the experimental results of C-V for enhancement type device is available in recent literature, a complete characterization of electrostatic property of depletion type Buried Channel Quantum Well FET (QWFET) structure is yet to be done. C-V characteristics of the device is studied with the variation of three important process parameters: Indium (In) composition, gate dielectric and oxide thickness. We observed that inversion capacitance and ballistic current tend to increase with the increase in Indium (In) content in InGaAs barrier layer.

Ahmed, Imtiaz; Alam, Md Hasibul; Chowdhury, Nadim; Azim, Zubair Al; Khosru, Quazi Deen Mohd

2012-01-01T23:59:59.000Z

308

Gradient instabilities of electromagnetic waves in Hall thruster plasma  

SciTech Connect

This paper presents a linear analysis of gradient plasma instabilities in Hall thrusters. The study obtains and analyzes the dispersion equation of high-frequency electromagnetic waves based on the two-fluid model of a cold plasma. The regions of parameters corresponding to unstable high frequency modes are determined and the dependence of the increments and intrinsic frequencies on plasma parameters is obtained. The obtained results agree with those of previously published studies.

Tomilin, Dmitry [Department of Electrophysics, Keldysh Research Centre, Moscow 125438 (Russian Federation)

2013-04-15T23:59:59.000Z

309

Design and operations of Hall thruster with segmented electrodes  

DOE Green Energy (OSTI)

Principles of the Hall thruster with segmented electrodes are explored. A suitable vacuum facility was put into service. For purposes of comparison between segmented and conventional thruster approaches, a modular laboratory prototype thruster was designed and built. Under conventional operation, the thruster achieves state-of-the-art efficiencies (56% at 300 V and 890 W). Very preliminary results under operation with segmented electrodes are also described.

Fisch, N.J.; Raitses, Y.; Dorf, L.A.; Litvak, A.A.

1999-12-10T23:59:59.000Z

310

Quantum chaos in elementary quantum mechanics  

E-Print Network (OSTI)

chaos in elementary quantum mechanics so-called integrableIntroduction to Quantum Mechanics (Englewoods Cliff, NJ:Lifshitz E M 1977 Quantum Mechanics (New York: Pergamon) [

Dabaghian, Yuri A; Jensen, R

2005-01-01T23:59:59.000Z

311

From quantum graphs to quantum random walks  

E-Print Network (OSTI)

We give a short overview over recent developments on quantum graphs and outline the connection between general quantum graphs and so-called quantum random walks.

Gregor Tanner

2005-04-29T23:59:59.000Z

312

The Echo of the Quantum Bounce  

E-Print Network (OSTI)

We identify a signature of quantum gravitational effects that survives from the early universe to the current era: Fluctuations of quantum fields as seen by comoving observers are significantly influenced by the history of the early universe. In particular we will show how the existence (or not) of a quantum bounce leaves a trace in the background quantum noise that is not damped and would be non-negligible even nowadays. Furthermore, we will estimate an upper bound to the typical energy and length scales where quantum effects are relevant. We will discuss how this signature might be observed and therefore used to build falsifiability tests of quantum gravity theories.

Luis J. Garay; Mercedes Martin-Benito; Eduardo Martin-Martinez

2013-08-20T23:59:59.000Z

313

Habitat Restoration/Enhancement Fort Hall Reservation : 2001 Annual Report.  

DOE Green Energy (OSTI)

Habitat enhancement, protection and monitoring were the focus of the Resident Fisheries Program during 2001. Enhancement and protection included sloping, fencing and planting willows at sites on Diggie Creek, Clear Creek and Spring Creek. In addition, many previously constructed instream structures (rock barbs and wing dams) were repaired throughout the Fort Hall Indian Reservation (Reservation). In 2001, exclosure fences were erected on Diggie Creek (250 m barbed wire; (70 m jack), Wood Creek (500 m jack), Clear Creek (20 m jack), Ross Fork Creek (200 m jack), West Fork Creek (200 m jack)) and the Portneuf River (1 km barbed wire; 100 m jack). Jack and rail exclosure fences that had deteriorated over the past ten years were repaired at numerous areas throughout the Reservation. Physical sampling during 2001 included sediment and depth surveys (SADMS) in Big Jimmy Creek and Diggie Creek. SADMS, used to track changes in channel morphology and specifically track movements of silt through Bottoms stream systems were completed for eight and nine strata in the Big Jimmy and Diggie Creek, respectively. Baseline SADM data was collected in Diggie Creek to monitor the effects of bank sloping and revegetation on channel morphology and sediment levels through time. Water temperature was monitored (hourly) in Spring Creek, Clear Creek, Ross Fork Creek and Big Jimmy Creek. Biotic sampling included invertebrate sampling in the 200 and 300 series of Clear Creek. Fish population densities and biomass were sampled in Clear Creek 200 and 300 series. Sampling protocols were identical to methods used in past years. Numbers of fish in Clear Creek 300 series remained similar to 2000 while numbers of fish in Clear Creek 200 series dropped to near pre project levels. Salmonid fry densities were monitored near Broncho Bridge and were significantly higher than 2000. A mark-recapture study was initiated in spring 2001 to estimate numbers of spawning adults using the Head End of Spring Creek Mean catch rate by anglers on Bottoms streams increased from 0.55 in 2000 to 0.77 fish per hour in 2001. Numbers of fish 18 inches caught by anglers decreased from 0.41 in 2000 to 0.19 in 2001.

Moser, David C.

2003-03-01T23:59:59.000Z

314

Technology Commercialization and Partnerships | BSA 07-12 ...  

The experimental observation of quantum Hall effect of I=3 chiral quasiparticles in trilayer graphene (.pdf) Press Releases.

315

Quantum Communications  

Science Conference Proceedings (OSTI)

... In summary, we perform research and development (R&D) in quantum communication and related measurement areas with an emphasis on ...

2013-07-24T23:59:59.000Z

316

Quantum Electrical Measurements Portal  

Science Conference Proceedings (OSTI)

NIST Home > Quantum Electrical Measurements Portal. Quantum Electrical Measurements Portal. Subject Areas. Electrical ...

2013-03-21T23:59:59.000Z

317

Effects of external fields on the excitonic emission from single InAs/GaAs quantum dots  

Science Conference Proceedings (OSTI)

A low-temperature micro-photoluminescence (?-PL) investigation of InAs/GaAs quantum dots (QDs) exposed to a lateral external electric field is reported. It is demonstrated that the QDs PL signal could be increased several times by altering the ... Keywords: Exciton, Micro-luminescence, Quantum dot

P. O. Holtz; E. S. Moskalenko; M. Larsson; K. F. Karlsson; W. V. Schoenfeld; P. M. Petroff

2008-03-01T23:59:59.000Z

318

Quantum Networks for Generating Arbitrary Quantum States  

E-Print Network (OSTI)

Quantum protocols often require the generation of specific quantum states. We describe a quantum algorithm for generating any prescribed quantum state. For an important subclass of states, including pure symmetric states, this algorithm is efficient.

Phillip Kaye; Michele Mosca

2004-07-14T23:59:59.000Z

319

Magnetoacoustic solitons in quantum plasma  

SciTech Connect

Nonlinear magnetoacoustic waves in collisionless homogenous, magnetized quantum plasma is studied. Two fluid quantum magneto-hydrodynamic model (QMHD) is employed and reductive perturbation method is used to derive Korteweg de Vries (KdV) equation for magnetoacoustic waves. The effects of plasma density and magnetic field intensity are investigated on magnetoacoustic solitary structures in quantum plasma. The numerical results are also presented, which are applicable to explain some aspects of the propagation of nonlinear magnetoacosutic wave in dense astrophysical plasma situations.

Hussain, S.; Mahmood, S. [Theoretical Plasma Physics Division (TPPD), PINSTECH, P.O. Nilore, Islamabad (Pakistan); Department of Physics and Applied Mathematics (DPAM), PIEAS, P.O. Nilore, Islamabad (Pakistan)

2011-08-15T23:59:59.000Z

320

TBB-0042 - In the Matter of Curtis Hall | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

TBB-0042 - In the Matter of Curtis Hall TBB-0042 - In the Matter of Curtis Hall TBB-0042 - In the Matter of Curtis Hall This letter concerns the complaint of retaliation filed by Curtis Hall (the complainant or Mr. Hall) with the Department of Energy under 10 C . F. R. Part 7 0 8 , the DOE Con tractor Employee (Whistleblower) Protection Program. On March 13, 2008, the Office of Hearings and Appeals (OHA) received your Petition for Secretarial Review of the appeal decision we issued on February 13, 2008. Under Part 708 regulations, the Secretary will reverse or revise an appeal decision by the Director of OHA only in extraordinary circumstances. 10 C.F.R. § 708.35(d). tbb0042.pdf More Documents & Publications TBA-0042 - In the Matter of Curtis Hall TBB-0030 - In the Matter of Curtis Broaddus

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Diversity Town Hall Draws a Crowd at the Energy Department | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Diversity Town Hall Draws a Crowd at the Energy Department Diversity Town Hall Draws a Crowd at the Energy Department Diversity Town Hall Draws a Crowd at the Energy Department December 12, 2011 - 1:43pm Addthis Secretary Chu speaks at the Workforce Diversity and Inclusion Town Hall on December 6, 2011. | Energy Department file photo. Secretary Chu speaks at the Workforce Diversity and Inclusion Town Hall on December 6, 2011. | Energy Department file photo. Karissa Marcum Public Affairs Specialist, Office of Public Affairs "For our own good, we want as wide of a talent pool as we can get." Secretary Steven Chu The Energy Department held a Workforce Diversity and Inclusion Town Hall event on December 6th, delivering on Secretary Steven Chu's commitment to promoting a culture that strongly values diversity and inclusion.

322

Diversity Town Hall Draws a Crowd at the Energy Department | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Diversity Town Hall Draws a Crowd at the Energy Department Diversity Town Hall Draws a Crowd at the Energy Department Diversity Town Hall Draws a Crowd at the Energy Department December 12, 2011 - 1:43pm Addthis Secretary Chu speaks at the Workforce Diversity and Inclusion Town Hall on December 6, 2011. | Energy Department file photo. Secretary Chu speaks at the Workforce Diversity and Inclusion Town Hall on December 6, 2011. | Energy Department file photo. Karissa Marcum Public Affairs Specialist, Office of Public Affairs "For our own good, we want as wide of a talent pool as we can get." Secretary Steven Chu The Energy Department held a Workforce Diversity and Inclusion Town Hall event on December 6th, delivering on Secretary Steven Chu's commitment to promoting a culture that strongly values diversity and inclusion.

323

After 105 Years, Historic City Hall in West Des Moines, Iowa Goes Green |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

After 105 Years, Historic City Hall in West Des Moines, Iowa Goes After 105 Years, Historic City Hall in West Des Moines, Iowa Goes Green After 105 Years, Historic City Hall in West Des Moines, Iowa Goes Green May 9, 2011 - 5:22pm Addthis The restored Historic City Hall building in West Des Moines' Valley Junction neighborhood. | Photo credit: Vicky Saylor The restored Historic City Hall building in West Des Moines' Valley Junction neighborhood. | Photo credit: Vicky Saylor April Saylor April Saylor Former Digital Outreach Strategist, Office of Public Affairs The city of West Des Moines, Iowa is using funding from the Recovery Act to renovate the Historic City Hall building located in Valley Junction, a charming neighborhood that boasts a weekly farmer's market, a block party during the summer months and unique shopping throughout the year.

324

Multiphoton Quantum Optics and Quantum State Engineering  

E-Print Network (OSTI)

We present a review of theoretical and experimental aspects of multiphoton quantum optics. Multiphoton processes occur and are important for many aspects of matter-radiation interactions that include the efficient ionization of atoms and molecules, and, more generally, atomic transition mechanisms; system-environment couplings and dissipative quantum dynamics; laser physics, optical parametric processes, and interferometry. A single review cannot account for all aspects of such an enormously vast subject. Here we choose to concentrate our attention on parametric processes in nonlinear media, with special emphasis on the engineering of nonclassical states of photons and atoms. We present a detailed analysis of the methods and techniques for the production of genuinely quantum multiphoton processes in nonlinear media, and the corresponding models of multiphoton effective interactions. We review existing proposals for the classification, engineering, and manipulation of nonclassical states, including Fock states...

Dell'Anno, F; Illuminati, F; 10.1016/j.physrep.2006.01.004

2009-01-01T23:59:59.000Z

325

Gaussian quantum information  

E-Print Network (OSTI)

The science of quantum information has arisen over the last two decades centered on the manipulation of individual quanta of information, known as quantum bits or qubits. Quantum computers, quantum cryptography, and quantum ...

Weedbrook, Christian

326

Introduction to spin Hall effect Spin-Dependent Lorentz Force ...  

Science Conference Proceedings (OSTI)

... new generation of spintronic devices This system forms a prototype spintronics device an analogue to a transistor ...

2013-03-11T23:59:59.000Z

327

Energy and Effective Mass Dependence of Electron Tunnelling Through Multiple Quantum barriers in Different Heterostructures  

E-Print Network (OSTI)

Tunneling of electrons through the barriers in heterostructures has been studied, within unified transfer matrix approach. The effect of barrier width on the transmission coefficient of the electrons has been investigated for different pairs of semi conducting materials that are gaining much importance recently. These pairs include CdS/CdSe, AlGaAs/GaAs and InAs/AlSb. Barrier dimensions have been reduced from 20nm to 5nm to observe the effect of scaling on tunneling properties. Material depended is highlighted for electrons with energy varying from below the barrier height to above it. The electron effective mass inside the barrier and the well are often different. The results show that the coupling effect leads to significant changes on the transmission effect. . The effective-mass dependant transmission coefficient has been plotted with respect to electron energy. The computation is based on the transfer matrix method by using MATLAB.

Jatindranath Gain; Madhumita Das Sarkar; Sudakshina Kundu

2010-02-09T23:59:59.000Z

328

Quantum Path Interference through Incoherent Motions in Multilevel Quantum Systems  

E-Print Network (OSTI)

The fluctuating incoherent environment in the condensed phase plays an important role in the dynamics and steady states of open quantum systems. The most fascinating aspect in open quantum systems is quantum coherence induced by path interference of incoherent motions. We propose a modified Ehrenfest scheme to study the path interference of incoherent motions in multi-level quantum systems. The detailed balance is enforced by considering the quantum correction of two-time correction functions based on second order master (rate) equations. With the modified Ehrenfest method, we can study the steady state populations and other quantum observables under different thermal dynamic conditions, such as energy relaxation and non-Markovian effects. For the three level system under incoherent coupling, we show how the steady state populations are influenced by the quantum path interference of incoherent fluctuations (Agarwal-Fano-like interference). We discuss the modified Ehrenfest method and its connection with stochastic Langevin equations and second order master equations. Most existing quantum MD simulation methods, particularly Master equation techniques, fall into the category of the weak coupling limit due to the nature of detailed balance. Although the modified Ehrenfest method is amicable to second-order master equations, it is actually a better way to model the quantum path interference since it preserves multi-time memory kernels. Therefore, it enables us to study the quantum path interference. This method can be used as quantum MD simulators for large open quantum systems like solar cell, (organic) LED, etc. The future extension of this method beyond the modified Ehrenfest scheme can be done with efficient wavepacket propagation methods by treating the bath modes in full quantum mechanical way.

Xin Chen

2013-05-17T23:59:59.000Z

329

Recents results and future measurements for few body problems in Hall A  

Science Conference Proceedings (OSTI)

I will summarize the latest results in Hall A linked to Few-Body problems and the future measurements planned after the 12 GeV upgrade.

Alexandre Camsonne

2011-08-01T23:59:59.000Z

330

A photon calorimeter using lead tungstate crystals for the CEBAF Hall A Compton polarimeter  

E-Print Network (OSTI)

The performances of the calorimeter of the Jlab Hall A Compton Polarimeter have been measured using the Mainz tagged photon beam.

D. Neyret; T. Pussieux

1999-07-25T23:59:59.000Z

331

Investigation of Low Discharge Voltage Hall Thruster Characteristics and Evaluation of Loss Mechanisms.  

E-Print Network (OSTI)

??During the early development stages of Hall thruster technology, plasma research and propulsion advancements centered primarily on 300-V, 1600-s specific impulse operation. Since the first (more)

Brown, Daniel Lucas

2009-01-01T23:59:59.000Z

332

The Honoradle':Rudolf Juiliani City'Hall New York, New York I0007  

Office of Legacy Management (LM)

1 .' Department oft Endrgy :. ' . ' . Wasthgton, DC 20585 ' ,,' . .' . . s ,' FEi,l 6 jg& ,. . . ' I s. i ,-' .' ,, -. ,. The Honoradle':Rudolf Juiliani City'Hall New York,...

333

Building America Top Innovations Hall of Fame Profile … Low-Cost Ventilation in Production Housing  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

simple, cost-effective techniques for providing fresh air throughout the home, including exhaust-only and central fan-integrated supply ventilation. Building America has refined simple whole-house ventilation systems that cost less than $350 to install. BUILDING AMERICA TOP INNOVATIONS HALL OF FAME PROFILE INNOVATIONS CATEGORY: 1. Advanced Technologies and Practices 1.3 Assured Health, Safety, and Durability Low-Cost Ventilation in Production Housing As high-performance homes get more air-tight and better insulated, attention to good indoor air quality becomes essential. Building America has effectively guided the nation's home builders to embrace whole-house ventilation by developing low-cost options that adapt well to their production processes. When the U.S. Department of Energy's Building America research teams began

334

Quantum Mechanical Calculations of Charge Effects on gating the KcsA channel  

DOE Green Energy (OSTI)

The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. A series of ab initio (density functional) calculations were carried out on side chains of a set of amino acids, plus water, from the (intracellular) gating region of the KcsA K+ channel. Their atomic coordinates, except hydrogen, are known from X-ray structures [D.A. Doyle, J.M. Cabral, R.A. Pfuetzner, A. Kuo, J.M. Gulbis, S.L. Cohen, B.T. Chait, R. MacKinnon, The structure of the potassium channel: molecular basis of K+ conduction and selectivity, Science 280 (1998) 6977; R. MacKinnon, S.L. Cohen, A. Kuo, A. Lee, B.T. Chait, Structural conservation in prokaryotic and eukaryotic potassium channels, Science 280 (1998) 106109; Y. Jiang, A. Lee, J. Chen, M. Cadene, B.T. Chait, R. MacKinnon, The open pore conformation of potassium channels. Nature 417 (2001) 523526], as are the coordinates of some water oxygen atoms. The 1k4c structure is used for the starting coordinates. Quantum mechanical optimization, in spite of the starting configuration, places the atoms in positions much closer to the 1j95, more tightly closed, configuration. This state shows four water molecules forming a basket under the Q119 side chains, blocking the channel. When a hydrated K+ approaches this basket, the optimized system shows a strong set of hydrogen bonds with the K+ at defined positions, preventing further approach of the K+ to the basket. This optimized structure with hydrated K+ added shows an ice-like 12 molecule nanocrystal of water. If the water molecules exchange, unless they do it as a group, the channel will remain blocked. The basket itself appears to be very stable, although it is possible that the K+ with its hydrating water molecules may be more mobile, capable of withdrawing from the gate. It is also not surprising that water essentially freezes, or forms a kind of glue, in a nanometer space; this agrees with experimental results on a rather different, but similarly sized (nm dimensions) system [K.B. Jinesh, J.W.M. Frenken, Capillary condensation in atomic scale friction: how water acts like a glue, Phys. Rev. Lett. 96 (2006) 166103/14].

Kariev, Alisher M.; Znamenskiy, Vasiliy S.; Green, Michael E.

2007-02-06T23:59:59.000Z

335

Quantum Mechanics Summary/Review Spring 2009 Compton Lecture Series  

E-Print Network (OSTI)

Quantum Mechanics Summary/Review Spring 2009 Compton Lecture Series: From Quantum Mechanics one component at a time. · Planck's constant determines the scale at which quantum mechanical effects could get rid of quantum mechanical effects ­ The "wavelength" of particles given by h mv would all

336

Quantum Weak Measurements and Cosmology  

E-Print Network (OSTI)

The indeterminism of quantum mechanics generally permits the independent specification of both an initial and a final condition on the state. Quantum pre-and-post-selection of states opens up a new, experimentally testable, sector of quantum mechanics, when combined with statistical averages of identical weak measurements. In this paper I apply the theory of weak quantum measurements combined with pre-and-post-selection to cosmology. Here, pre-selection means specifying the wave function of the universe or, in a popular semi-classical approximation, the initial quantum state of a subset of quantum fields propagating in a classical back-ground spacetime. The novel feature is post-selection: the additional specification of a condition on the quantum state in the far future. I discuss "natural" final conditions, and show how they may lead to potentially large and observable effects at the present cosmological epoch. I also discuss how pre-and-post-selected quantum contrast to the expectation value of the stress-energy-momentum tensor, resolving a vigorous debate from the 1970's. The paper thus provides a framework for computing large-scale cosmological effects arising from this new sector of quantum mechanics. A simple experimental test is proposed.

Paul Davies

2013-09-03T23:59:59.000Z

337

Titanium diboride ceramic fiber composites for Hall-Heroult cells  

DOE Patents (OSTI)

An improved cathode structure is described for Hall-Heroult cells for the electrolytic production of aluminum metal. This cathode structure is a preform fiber base material that is infiltrated with electrically conductive titanium diboride using chemical vapor infiltration techniques. The structure exhibits good fracture toughness, and is sufficiently resistant to attack by molten aluminum. Typically, the base can be made from a mat of high purity silicon carbide fibers. Other ceramic or carbon fibers that do not degrade at temperatures below about 1000 C can be used.

Besmann, T.M.; Lowden, R.A.

1990-05-29T23:59:59.000Z

338

Titanium diboride ceramic fiber composites for Hall-Heroult cells  

DOE Patents (OSTI)

An improved cathode structure for Hall-Heroult cells for the electrolytic production of aluminum metal. This cathode structure is a preform fiber base material that is infiltrated with electrically conductive titanium diboride using chemical vapor infiltration techniques. The structure exhibits good fracture toughness, and is sufficiently resistant to attack by molten aluminum. Typically, the base can be made from a mat of high purity silicon carbide fibers. Other ceramic or carbon fibers that do not degrade at temperatures below about 1000 deg. C can be used.

Besmann, Theodore M. (Knoxville, TN); Lowden, Richard A. (Knoxville, TN)

1990-01-01T23:59:59.000Z

339

3D Hall MHD Modeling of Solar Wind Plasma Spectra  

E-Print Network (OSTI)

We present fully self consistent 3D simulations of compressible Hall MHD plasma that describe spectral features relevant to the solar wind plasma. We find that a $k^{-7/3}$ spectrum sets in for the fluctuations that are smaller than ion gyro radius. We further investigate scale dependent anisotropy led by nonlinear processes relevant to the solar wind plasma. Our work is important particularly in understanding the role of wave and nonlinear cascades in the evolution of the solar wind, structure formation at the largest scales.

Shaikh, Dastgeer

2009-01-01T23:59:59.000Z

340

Electric Time in Quantum Cosmology  

E-Print Network (OSTI)

Effective quantum cosmology is formulated with a realistic global internal time given by the electric vector potential. New possibilities for the quantum behavior of space-time are found, and the high-density regime is shown to be very sensitive to the specific form of state realized.

Stephon Alexander; Martin Bojowald; Antonino Marciano; David Simpson

2012-12-10T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Classical and quantum correlative capacities of quantum systems  

SciTech Connect

How strongly can one system be correlated with another? In the classical world, this basic question concerning correlative capacity has a very satisfying answer: The ''effective size'' of the marginal system, as quantified by the Shannon entropy, sets a tight upper bound to the correlations, as quantified by the mutual information. Although in the quantum world bipartite correlations, like their classical counterparts, are also well quantified by mutual information, the similarity ends here: The correlations in a bipartite quantum system can be twice as large as the marginal entropy. In the paradigm of quantum discord, the correlations are split into classical and quantum components, and it was conjectured that both the classical and quantum correlations are (like the classical mutual information) bounded above by each subsystem's entropy. In this work, by exploiting the interplay between entanglement of formation, mutual information, and quantum discord, we disprove that conjecture. We further indicate a scheme to restore harmony between quantum and classical correlative capacities. The results illustrate dramatically the asymmetric nature of quantum discord and highlight some subtle and unusual features of quantum correlations.

Li Nan; Luo Shunlong [Academy of Mathematics and Systems Science, Chinese Academy of Sciences, 100190 Beijing (China)

2011-10-15T23:59:59.000Z

342

Plasmon scattering approach to energy exchange and high frequency noise in = 2 quantum Hall edge channels  

E-Print Network (OSTI)

channels P. Degiovanni1 , Ch. Grenier1 , G. F`eve2 , C. Altimiras3 , H. le Sueur3 , and F. Pierre3 (1. Rev. B 78, 045322 (2008). [8] P. Degiovanni, C. Grenier, and G. F`eve, http://arxiv.org/abs/0907 and X.G. Wen, Phys. Rev. B. 49, 8227 (1994). [19] J. Han and D. Thouless, Phys. Rev. B 55, R1926 (1997

Paris-Sud XI, Université de

343

Quantum Hall states of bosons in rotating anharmonic traps Nicolas Rougerie  

E-Print Network (OSTI)

where the gas is no longer confined against centrifugal forces. This is the main source of difficulty term. The quartic term improves the stability of the system against centrifugal deconfinement questions [1­3]. The formal similarity between the Hamiltonian of a rotating Bose gas and that of a 2D

344

Quantum Hamiltonian diagonalization and Equations of Motion with Berry Phase Corrections  

E-Print Network (OSTI)

It has been recently found that the equations of motion of several semiclassical systems must take into account anomalous velocity terms arising from Berry phase contributions. Those terms are for instance responsible for the spin Hall effect in semiconductors or the gravitational birefringence of photons propagating in a static gravitational field. Intensive ongoing research on this subject seems to indicate that actually a broad class of quantum systems might have their dynamics affected by Berry phase terms. In this article we review the implication of a new diagonalization method for generic matrix valued Hamiltonians based on a formal expansion in power of $\\hbar$. In this approach both the diagonal energy operator and dynamical operators which depend on Berry phase terms and thus form a noncommutative algebra, can be expanded in power series in \\hbar $. Focusing on the semiclassical approximation, we will see that a large class of quantum systems, ranging from relativistic Dirac particles in strong external fields to Bloch electrons in solids have their dynamics radically modified by Berry terms.

Pierre Gosselin; Alain Berard; Herve Mohrbach

2008-05-17T23:59:59.000Z

345

Foundations of quantum theory and thermodynamics  

Science Conference Proceedings (OSTI)

Physical reasons to support the statement that Quantum theory (Quantum Gravity in particular as well as Classical Gravity) loose applicability due to Thermodynamical effects are presented. The statement is based on several points: 1. N.Bohr requirement that measuring units must have macro size is one of common fundamentals of Quantum theory. 2. The Reference Systemthe base notion of Classical and Quantum theory and of any observation process as well

Victor Olkhov

1998-01-01T23:59:59.000Z

346

Quantum Computational Complexity  

E-Print Network (OSTI)

This article surveys quantum computational complexity, with a focus on three fundamental notions: polynomial-time quantum computations, the efficient verification of quantum proofs, and quantum interactive proof systems. Properties of quantum complexity classes based on these notions, such as BQP, QMA, and QIP, are presented. Other topics in quantum complexity, including quantum advice, space-bounded quantum computation, and bounded-depth quantum circuits, are also discussed.

John Watrous

2008-04-21T23:59:59.000Z

347

Building America Top Innovations Hall of Fame Profile … Basement Insulation Systems  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Efficient Efficient and durable construction practices are critical for basements because basements can account for 10% to 30% of a home's total heat loss and provide significant risk of moisture problems due to extensive cold surfaces at the walls and slab. BUILDING AMERICA TOP INNOVATIONS HALL OF FAME PROFILE INNOVATIONS CATEGORY: 1. Advanced Technologies and Practices 1.1 Building Science Solutions Basement Insulation Systems Building America research has provided essential guidance for one of the most challenging construction assemblies in cold-climate high-performance homes. Basements can easily develop mold, rot, and odor problems if not designed properly. Building America researchers have investigated basement insulation systems that keep the space dry, healthy, and odor-free. These systems effectively address the

348

Radiation Hardness Tests of SiPMs for the JLab Hall D Barrel Calorimeter  

E-Print Network (OSTI)

We report on the measurement of the neutron radiation hardness of silicon photomultipliers (SiPMs) manufactured by Hamamatsu Corporation in Japan and SensL in Ireland. Samples from both companies were irradiated by neutrons created by a 1 GeV electron beam hitting a thin lead target at Jefferson Lab Hall A. More tests regarding the temperature dependence of the neutron radiation damage and self-annealing were performed on Hamamatsu SiPMs using a calibrated Am-Be neutron source from the Jefferson Lab Radiation Control group. As the result of irradiation both dark current and dark rate increase linearly as a function of the 1 MeV equivalent neutron fluence and a temperature dependent self-annealing effect is observed.

Yi Qiang; Carl Zorn; Fernando Barbosa; Elton Smith

2012-07-16T23:59:59.000Z

349

Radiation Hardness Tests of SiPMs for the JLab Hall D Barrel Calorimeter  

E-Print Network (OSTI)

We report on the measurement of the neutron radiation hardness of silicon photomultipliers (SiPMs) manufactured by Hamamatsu Corporation in Japan and SensL in Ireland. Samples from both companies were irradiated by neutrons created by a 1 GeV electron beam hitting a thin lead target at Jefferson Lab Hall A. More tests regarding the temperature dependence of the neutron radiation damage and self-annealing were performed on Hamamatsu SiPMs using a calibrated Am-Be neutron source from the Jefferson Lab Radiation Control group. As the results of all irradiation, both dark current and dark noise increase linearly as a function of the 1 MeV equivalent neutron fluence and a temperature dependent self-annealing effect is observed together with the radiation damage.

Qiang, Yi; Barbosa, Fernando; Smith, Elton

2012-01-01T23:59:59.000Z

350

Radiation Hardness Tests of SiPMs for the JLab Hall D Barrel Calorimeter  

SciTech Connect

We report on the measurement of the neutron radiation hardness of silicon photomultipliers (SiPMs) manufactured by Hamamatsu Corporation in Japan and SensL in Ireland. Samples from both companies were irradiated by neutrons created by a 1 GeV electron beam hitting a thin lead target at Jefferson Lab Hall A. More tests regarding the temperature dependence of the neutron radiation damage and self-annealing were performed on Hamamatsu SiPMs using a calibrated AmBe neutron source from the Jefferson Lab Radiation Control group. As the result of irradiation both dark current and dark rate increase linearly as a function of the 1 MeV equivalent neutron fluence and a temperature dependent self-annealing effect is observed

Yi Qiang, Carl Zorn, Fernando Barbosa, Elton Smith

2013-01-01T23:59:59.000Z

351

Putting Light to Work at the Quantum Scale | U.S. DOE Office...  

Office of Science (SC) Website

One author (J Rho) had support from the Samsung Scholarship Foundation, Republic of Korea. Publications X. Yin, Z. Ye, J. Rho, Y. Wang, and X. Zhang, "Photonic Spin Hall Effect...

352

Robert B. Laughlin, 1984 | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

demonstration that correlated motion of electrons can lead to a previously unknown form of quantum liquid, thereby providing an understanding of the fractional quantum Hall effect...

353

Conservation became a team sport in University of Minnesota residence halls during spring semester 2011,  

E-Print Network (OSTI)

Benefits Conservation became a team sport in University of Minnesota residence halls during spring the Conservation Madness recycling and energy reduction competition. The contest rewarded the residence hall recycling generated. The competition's goal was to encourage students to continue conserving university

Webb, Peter

354

A study of cylindrical Hall thruster for low power space applications  

DOE Green Energy (OSTI)

A 9 cm cylindrical thruster with a ceramic channel exhibited performance comparable to the state-of-the-art Hall thrusters at low and moderate power levels. Significantly, its operation is not accompanied by large amplitude discharge low frequency oscillations. Preliminary experiments on a 2 cm cylindrical thruster suggest the possibility of a high performance micro Hall thruster.

Y. Raitses; N.J. Fisch; K.M. Ertmer; C.A. Burlingame

2000-07-27T23:59:59.000Z

355

Physicalism versus quantum mechanics  

E-Print Network (OSTI)

Foundations of Quantum Mechanics. (Princeton UniversityMind, Matter, and Quantum Mechanics, (Springer, Berlin & NewMindful Universe: Quantum Mechanics and the Participating

Stapp, Henry P; Theoretical Physics Group; Physics Division

2009-01-01T23:59:59.000Z

356

The Localized Quantum Vacuum Field  

E-Print Network (OSTI)

A model for the localized quantum vacuum is proposed in which the zero-point energy of the quantum electromagnetic field originates in energy- and momentum-conserving transitions of material systems from their ground state to an unstable state with negative energy. These transitions are accompanied by emissions and re-absorptions of real photons, which generate a localized quantum vacuum in the neighborhood of material systems. The model could help resolve the cosmological paradox associated to the zero-point energy of electromagnetic fields, while reclaiming quantum effects associated with quantum vacuum such as the Casimir effect and the Lamb shift; it also offers a new insight into the Zitterbewegung of material particles.

Daniela Dragoman

2006-03-01T23:59:59.000Z

357

The design and performance of the electromagnetic calorimeters in Hall C at Jefferson Lab  

Science Conference Proceedings (OSTI)

The design and performance of the electromagnetic calorimeters in the magnetic spectrometers in Hall C at Jefferson Lab are presented. For the existing HMS and SOS spectrometers, construction information and comparisons of simulated and experimental results are presented. The design and simulated performance for a new calorimeter to be used in the new SHMS spectrometer is also presented. We have developed and constructed electromagnetic calorimeters from TF-1 type lead-glass blocks for the HMS and SOS magnetic spectrometers at JLab Hall C. The HMS/SOS calorimeters are of identical design and construction except for their total size. Blocks of dimension 10 cm 10 cm 70 cm are arranged in four planes and stacked 13 and 11 blocks high in the HMS and SOS respectively. The energy resolution of these calorimeters is better than 6%/?E, and pion/electron (?/e) separation of about 100:1 has been achieved in energy range 15 GeV. Good agreement has been observed between the experimental and GEANT4 simulated energy resolutions. The HMS/SOS calorimeters have been used nearly in all Hall C experiments, providing good energy resolution and a high pion suppression factor. No significant deterioration in their performance has been observed in the course of use since 1994. For the SHMS spectrometer, presently under construction, details on the calorimeter design and accompanying GEANT4 simulation efforts are given. A Preshower+Shower design was selected as the most cost-effective among several design choices. The preshower will consist of a layer of 28 modules with TF-1 type lead glass radiators, stacked in two columns. The shower part will consist of 224 modules with F-101 type lead glass radiators, stacked in a fly's eye configuration of 14 columns and 16 rows. The active area of 120 130 cm(2) will encompass the beam envelope at the calorimeter. The anticipated performance of the new calorimeter is simulated over the full momentum range of the SHMS, predicting resolution and yields similar to the HMS calorimeter. Good electron/hadron separation can be achieved by using energy deposition in the Preshower along with total energy deposition in the calorimeter. In this case the PID capability is similar to or better than that attainable with HMS calorimeter, with a pion suppression factor of a few hundreds predicted for 99% electron detection efficiency.

Vardan Tadevosyan, Hamlet Mkrtchyan, Arshak Asaturyan, Arthur Mkrtchyan, Simon Zhamkochyan

2012-12-01T23:59:59.000Z

358

Electric quantum walks with individual atoms  

E-Print Network (OSTI)

We report on the experimental realization of electric quantum walks, which mimic the effect of an electric field on a charged particle in a lattice. Starting from a textbook implementation of discrete-time quantum walks, we introduce an extra operation in each step to implement the effect of the field. The recorded dynamics of such a quantum particle exhibits features closely related to Bloch oscillations and interband tunneling. In particular, we explore the regime of strong fields, demonstrating contrasting quantum behaviors: quantum resonances vs. dynamical localization depending on whether the accumulated Bloch phase is a rational or irrational fraction of 2\\pi.

Maximilian Genske; Wolfgang Alt; Andreas Steffen; Albert H. Werner; Reinhard F. Werner; Dieter Meschede; Andrea Alberti

2013-02-08T23:59:59.000Z

359

WIPP Employee Inducted Into Mine Rescue Hall of Fame - WIPP Teams  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Employee Inducted Into Mine Rescue Hall of Fame - WIPP Teams Employee Inducted Into Mine Rescue Hall of Fame - WIPP Teams Recognized at National Competition WIPP Employee Inducted Into Mine Rescue Hall of Fame - WIPP Teams Recognized at National Competition August 2, 2013 - 12:00pm Addthis Waste Isolation Pilot Plant Blue Mine Rescue Team Captain Gary Kessler (right) receives an award from Neal Merrifield, administrator for the Mine Safety and Health Administration Metal/Non-Metal mines, after Kessler was inducted into the National Mine Rescue Hall of Fame on Aug. 1, 2013. Waste Isolation Pilot Plant Blue Mine Rescue Team Captain Gary Kessler (right) receives an award from Neal Merrifield, administrator for the Mine Safety and Health Administration Metal/Non-Metal mines, after Kessler was inducted into the National Mine Rescue Hall of Fame on Aug. 1, 2013.

360

G5, Challenges of Hall Measurements on Low Mobility Materials ...  

Science Conference Proceedings (OSTI)

E1, Quantum Dot Red/Green/Blue/White Light-Emitting Electroluminescent Devices with a Low Turn-on Voltage and High Brightness E2, Fabrication of Flexible...

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Efficient Estimators for Quantum Instanton Evaluation of theKinetic Isotope Effects: Application to the Intramolecular HydrogenTransfer in Pentadiene  

SciTech Connect

The quantum instanton approximation is used to compute kinetic isotope effects for intramolecular hydrogen transfer in cis-1,3-pentadiene. Due to the importance of skeleton motions, this system with 13 atoms is a simple prototype for hydrogen transfer in enzymatic reactions. The calculation is carried out using thermodynamic integration with respect to the mass of the isotopes and a path integral Monte Carlo evaluation of relevant thermodynamic quantities. Efficient 'virial' estimators are derived for the logarithmic derivatives of the partition function and the delta-delta correlation functions. These estimators require significantly fewer Monte Carlo samples since their statistical error does not increase with the number of discrete time slices in the path integral. The calculation treats all 39 degrees of freedom quantum-mechanically and uses an empirical valence bond potential based on a modified general AMBER force field.

Vanicek, Jiri; Miller, William H.

2007-06-13T23:59:59.000Z

362

Sensitivity of Quantum Walks with Perturbation  

E-Print Network (OSTI)

Quantum computers are susceptible to noises from the outside world. We investigate the effect of perturbation on the hitting time of a quantum walk and the stationary distribution prepared by a quantum walk based algorithm. The perturbation comes from quantizing a transition matrix Q with perturbation E (errors). We bound the perturbed quantum walk hitting time from above by applying Szegedy's work and the perturbation bounds with Weyl's perturbation theorem on classical matrix. Based on an efficient quantum sample preparation approach invented in {\\em speed-up via quantum sampling} and the perturbation bounds for stationary distribution for classical matrix, we find an upper bound for the total variation distance between the prepared quantum sample and the true quantum sample.

Chiang, Chen-Fu

2010-01-01T23:59:59.000Z

363

Sensitivity of Quantum Walks with Perturbation  

E-Print Network (OSTI)

Quantum computers are susceptible to noises from the outside world. We investigate the effect of perturbation on the hitting time of a quantum walk and the stationary distribution prepared by a quantum walk based algorithm. The perturbation comes from quantizing a transition matrix Q with perturbation E (errors). We bound the perturbed quantum walk hitting time from above by applying Szegedy's work and the perturbation bounds with Weyl's perturbation theorem on classical matrix. Based on an efficient quantum sample preparation approach invented in {\\em speed-up via quantum sampling} and the perturbation bounds for stationary distribution for classical matrix, we find an upper bound for the total variation distance between the prepared quantum sample and the true quantum sample.

Chen-Fu Chiang

2010-07-08T23:59:59.000Z

364

Photoluminescence enhancement of quantum dots with photonic structures  

Science Conference Proceedings (OSTI)

Photoluminescence (PL) of CdSe/ZnS quantum dots (QDs) deposited on Si and photonic crystals with packed silica spheres, are investigated with the purpose of establishing enhancement of PL. Quantum dots with size ~2.4nm are introduced into the solution ... Keywords: CdSe quantum dots, Photonic band gap, Silica spheres, Surface quantum size effects

K. Liu; R. Tsu

2009-04-01T23:59:59.000Z

365

NIF-0607-13692.ppt NIF Town Hall Meeting, June 16, 2007 1 Title page -APS, Orlando, FL, November 13,  

E-Print Network (OSTI)

NIF-0607-13692.ppt NIF Town Hall Meeting, June 16, 2007 1 Title page - APS, Orlando, FL, November, December 4, 2007, Edward I. Moses, NIC Director #12;NIF-0607-13692.ppt NIF Town Hall Meeting, June 16, 2007 on the Cosmos Limitless Clean Energy Eye on the Cosmos #12;NIF-0607-13692.ppt NIF Town Hall Meeting, June 16

366

Quantum and Classical Variance in the Quantum Realm  

E-Print Network (OSTI)

This paper examines the variance of quantum and classical predictions in the quantum realm, as well as unexpected presence and absence of variances. Some features are found that share an indirect commonality with the Aharonov-Bohm and Aharonov-Casher effects in that there is a quantum action in the absence of a force. Variances are also found in the presence of a force that are more subtle as they are of higher order. Significant variances related to the harmonic oscillator and particle in a box periods are found. This paper raises the question whether apparent quantum self-inconsistency may be examined internally, or must be empirically ascertained. These inherent variances may either point to inconsistencies in quantum mechanics that should be fixed, or that nature is manifestly more non-classical than expected. For the harmonic oscillator it is proven that the second spatial moment is the same in QM and CM.

Mario Rabinowitz

2007-07-08T23:59:59.000Z

367

Quantum discord in open quantum systems  

E-Print Network (OSTI)

Open quantum systems have attracted great attentions for the inevitable interaction between quantum systems and their environment would largely affect the features of interest in the systems. Quantum discord, as a measure of the total nonclassical correlation in a quantum system, includes but not only the distinct property of quantum entanglement. Quantum discord can exist in separated quantum states and it has been shown to play important roles in many fundamental physical problems and practical quantum information tasks. There have been plentiful investigations on the quantum discord and its counterpart classical correlation in open quantum systems. In this short review, we would focus on the recent development and applications of distinctive properties of quantum discord and classical correlation in open quantum systems. Several related experimental works are included.

Xu, Jin-Shi

2012-01-01T23:59:59.000Z

368

Quantum Coulomb Gases  

E-Print Network (OSTI)

Lectures on Quantum Coulomb gases delivered at the CIME summer school on Quantum Many Body Systems 2010

Jan Philip Solovej

2010-12-23T23:59:59.000Z

369

The Honorable'George Kubin City Hall Dear Mayor Kubin:  

Office of Legacy Management (LM)

_ Department of Energy _ Department of Energy Washington. QC 20% APR 0 3 1995 The Honorable'George Kubin City Hall Dear Mayor Kubin: Secretary.of Energy.Wazel O'Leary has.announced a new approach to openness in the Department of,Energy [DOE) and its communications with the public. In support'of this initiative, we are pleased to forward the enclosed information related to the former Mtchigan Chemical Corporation site in your jurisdiction that performed work for DOE's predecessor agencies. This information is provided for your information, use, and retention. DOE's Formerly'Utilized Sites Remedial Action Program is responsible for identification of sites used by DOE's predecessor agencies, determining their current radiological condition and, where it has authority, performing

370

Quadrupole Magnetic Center Definition Using the Hall Probe Measurement Technique  

NLE Websites -- All DOE Office Websites (Extended Search)

Quadrupole Magnetic Center Definition Quadrupole Magnetic Center Definition Using the Hall Probe Measurement Technique Isaac Vasserman Experimental Facility Division, Advanced Photon Source, Argonne National Laboratory 1. Introduction The linac coherent light source [LCLS] project [1] requires 5 µm straightness of the particle beam trajectory to achieve the desired goal of x-ray multiplication. The main source of beam trajectory distortion is misalignment of quadrupoles. The LCLS project will use a beam-based alignment technique to align the quadrupoles to the needed accuracy. An initial accuracy of the quadrupole alignment not worse than 50 µm is required [2]. A different technique could be used for this purpose. It would be though quite desirable to avoid using an additional magnetic measurement technique and to use

371

Hall MHD Stability and Turbulence in Magnetically Accelerated Plasmas  

Science Conference Proceedings (OSTI)

The object of the research was to develop theory and carry out simulations of the Z pinch and plasma opening switch (POS), and compare with experimental results. In the case of the Z pinch, there was experimental evidence of ion kinetic energy greatly in excess of the ion thermal energy. It was thought that this was perhaps due to fine scale turbulence. The simulations showed that the ion energy was predominantly laminar, not turbulent. Preliminary studies of a new Z pinch experiment with an axial magnetic field were carried out. The axial magnetic is relevant to magneto - inertial fusion. These studies indicate the axial magnetic field makes the Z pinch more turbulent. Results were also obtained on Hall magnetohydrodynamic instability of the POS.

H. R. Strauss

2012-11-27T23:59:59.000Z

372

Magnetic Blockade Mechanism for Quantum Nucleation of Superconducting Vortex-Antivortex Pairs in Zero External Magnetic Field  

E-Print Network (OSTI)

We propose a magnetic dual of the Coulomb blockade effect for quantum nucleation of flux vortex pairs in high-Tc superconducting (HTS) films and grain boundaries in zero applied field. The magnetic blockade instability occurs at {\\theta} = {\\pi}, where {\\theta} is the "vacuum" or theta angle. The {\\theta} term has recently been discussed in the context of several other systems, including charge and spin density waves, topological insulators, the quantum Hall effect, and spontaneous CP violation. Our model predicts a sharp pair creation threshold current at {\\theta} = {\\pi}, analogous to the Coulomb blockade voltage of a tunnel junction, and explains the observed thickness dependence of critical currents in HTS coated conductors. We use the Schr\\"odinger equation to compute the evolving macrostate amplitudes, coupled by a generalized tunneling matrix element. The simulations yield excellent quantitative agreement with measured voltage-current characteristics of bi-crystal and other HTS grain boundary junctions. The model also predicts non-sinusoidal behavior in the voltage oscillations resulting from time-correlated vortex tunneling.

J. H. Miller Jr.; A. I. Wijesinghe

2011-10-12T23:59:59.000Z

373

Quantum Criticality and Black Holes  

SciTech Connect

I will describe the behavior of a variety of condensed matter systems in the vicinity of zero temperature quantum phase transitions. There is a remarkable analogy between the hydrodynamics of such systems and the quantum theory of black holes. I will show how insights from this analogy have shed light on recent experiments on the cuprate high temperature superconductors. Studies of new materials and trapped ultracold atoms are yielding new quantum phases, with novel forms of quantum entanglement. Some materials are of technological importance: e.g. high temperature superconductors. Exact solutions via black hole mapping have yielded first exact results for transport coefficients in interacting many-body systems, and were valuable in determining general structure of hydrodynamics. Theory of VBS order and Nernst effect in cuprates. Tabletop 'laboratories for the entire universe': quantum mechanics of black holes, quark-gluon plasma, neutrons stars, and big-bang physics.

Sachdev, Subir (Harvard)

2007-08-22T23:59:59.000Z

374

'Dead Time' Limits Quantum Cryptography Speeds  

Science Conference Proceedings (OSTI)

... Not only does dead time limit the transmission rate of a message ... effects and paralyzability in high-speed quantum key distribution, New Journal of ...

2012-06-08T23:59:59.000Z

375

Entanglement enhances performance in microscopic quantum fridges  

E-Print Network (OSTI)

Understanding the thermodynamics of quantum systems is of fundamental importance, from both theoretical and experimental perspectives. A growing interest has been recently given to small self-contained quantum thermal machines, the functioning of which requires no external source of work or control, but only incoherent interactions with thermal baths. The simplicity of such machines makes them and ideal test-bed for exploring quantum thermodynamics. So far, however, the importance of quantum effects in these machines has remained elusive. Here we show that entanglement, the paradigmatical quantum effect, plays a fundamental role in small self-contained quantum refrigerators, as it can enhance cooling and energy transport -- except notably when the efficiency is close to the Carnot limit. Hence a truly quantum refrigerator can outperform a classical one. Furthermore, the amount of entanglement alone quantifies the enhancement in cooling. More generally, our work shows that entanglement opens new possibilities in thermodynamics.

Nicolas Brunner; Marcus Huber; Noah Linden; Sandu Popescu; Ralph Silva; Paul Skrzypczyk

2013-05-26T23:59:59.000Z

376

Functional quantum biology in photosynthesis and magnetoreception  

E-Print Network (OSTI)

Is there a functional role for quantum mechanics or coherent quantum effects in biological processes? While this question is as old as quantum theory, only recently have measurements on biological systems on ultra-fast time-scales shed light on a possible answer. In this review we give an overview of the two main candidates for biological systems which may harness such functional quantum effects: photosynthesis and magnetoreception. We discuss some of the latest evidence both for and against room temperature quantum coherence, and consider whether there is truly a functional role for coherence in these biological mechanisms. Finally, we give a brief overview of some more speculative examples of functional quantum biology including the sense of smell, long-range quantum tunneling in proteins, biological photoreceptors, and the flow of ions across a cell membrane.

Lambert, Neill; Cheng, Yuan-Chung; Li, Che-Ming; Chen, Guang-Yin; Nori, Franco

2012-01-01T23:59:59.000Z

377

Functional quantum biology in photosynthesis and magnetoreception  

E-Print Network (OSTI)

Is there a functional role for quantum mechanics or coherent quantum effects in biological processes? While this question is as old as quantum theory, only recently have measurements on biological systems on ultra-fast time-scales shed light on a possible answer. In this review we give an overview of the two main candidates for biological systems which may harness such functional quantum effects: photosynthesis and magnetoreception. We discuss some of the latest evidence both for and against room temperature quantum coherence, and consider whether there is truly a functional role for coherence in these biological mechanisms. Finally, we give a brief overview of some more speculative examples of functional quantum biology including the sense of smell, long-range quantum tunneling in proteins, biological photoreceptors, and the flow of ions across a cell membrane.

Neill Lambert; Yueh-Nan Chen; Yuan-Chung Cheng; Che-Ming Li; Guang-Yin Chen; Franco Nori

2012-05-04T23:59:59.000Z

378

Annealing effect on photovoltaic performance of CdSe quantum-dots-sensitized TiO2 nanorod solar cells  

Science Conference Proceedings (OSTI)

Large area rutile TiO2 nanorod arrays were grown on F:SnO2 (FTO) conductive glass using a hydrothermal method at low temperature. CdSe quantum dots (QDs) were deposited onto single-crystalline TiO2 nanorod arrays by a ...

Yitan Li, Lin Wei, Ruizi Zhang, Yanxue Chen, Jun Jiao

2012-01-01T23:59:59.000Z

379

Quantum control limited by quantum decoherence  

E-Print Network (OSTI)

We describe quantum controllability under the influences of the quantum decoherence induced by the quantum control itself. It is shown that, when the controller is considered as a quantum system, it will entangle with its controlled system and then cause quantum decoherence in the controlled system. In competition with this induced decoherence, the controllability will be limited by some uncertainty relation in a well-armed quantum control process. In association with the phase uncertainty and the standard quantum limit, a general model is studied to demonstrate the possibility of realizing a decoherence-free quantum control with a finite energy within a finite time. It is also shown that if the operations of quantum control are to be determined by the initial state of the controller, then due to the decoherence which results from the quantum control itself, there exists a low bound for quantum controllability.

Fei Xue; S. X. Yu; C. P. Sun

2005-07-22T23:59:59.000Z

380

Comprehending Quantum Theory from Quantum Fields  

E-Print Network (OSTI)

At the primary level of reality as described by quantum field theory, a fundamental particle like an electron represents a stable, discrete, propagating excited state of its underlying quantum field. QFT also tells us that the lowest vacuum state as well as the excited states of such a field is always very active with spontaneous, unpredictable quantum fluctuations. Also an underlying quantum field is known to be indestructible and immutable possessing the same value in each element of spacetime comprising the universe. These characteristics of the primary quantum fields together with the fact that the quantum fluctuations can be cogently substantiated to be quantum coherent throughout the universe provide a possible ontology of the quantum theory. In this picture, the wave function of a quantum particle represents the reality of the inherent quantum fluctuations at the core of the universe and endows the particle its counter intuitive quantum behavior.

Mani Bhaumik

2013-10-04T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Quantum network coding for quantum repeaters  

E-Print Network (OSTI)

This paper considers quantum network coding, which is a recent technique that enables quantum information to be sent on complex networks at higher rates than by using straightforward routing strategies. Kobayashi et al. have recently showed the potential of this technique by demonstrating how any classical network coding protocol gives rise to a quantum network coding protocol. They nevertheless primarily focused on an abstract model, in which quantum resource such as quantum registers can be freely introduced at each node. In this work, we present a protocol for quantum network coding under weaker (and more practical) assumptions: our new protocol works even for quantum networks where adjacent nodes initially share one EPR-pair but cannot add any quantum registers or send any quantum information. A typically example of networks satisfying this assumption is {\\emph{quantum repeater networks}}, which are promising candidates for the implementation of large scale quantum networks. Our results thus show, for the...

Satoh, Takahiko; Imai, Hiroshi

2012-01-01T23:59:59.000Z

382

Status of Hall B superconducting magnets for the CLAS12 detector at JLab  

Science Conference Proceedings (OSTI)

Hadron physics has been an essential part of the physics program with the CLAS detector in experimental hall B at Thomas Jefferson National Accelerator Facility (Jefferson Lab). With the 12 GeV upgrade of the CEBAF machine, hadron physics in Hall B will be extended to a new domain of higher mass resonances and the range of higher transferred momentum using up to 11 GeV electron beams and the upgraded CLAS12 detector. In this paper, status of the hall B superconducting magnets for the CLAS12 detector is presented.

Quettier, L; Kashy, D; Elouadrhiri, L; Salpietro, E; Schneider, W; Small, R; Leung, E; Juang, T; McMullin, J; Taylor, C; Xu, L; Wagner, B; Wang, B; Wang, M

2011-12-01T23:59:59.000Z

383

Hall B superconducting magnets for the CLAS12 detector at JLAB  

Science Conference Proceedings (OSTI)

Hadron physics has been an essential part of the physics program with the CLAS detector in experimental hall B at Thomas Jefferson National Accelerator Facility (Jefferson Lab). With the 12 GeV upgrade of the CEBAF machine, hadron physics in Hall B will be extended to a new domain of higher mass resonances and the range of higher transferred momentum using up to 11 GeV electron beams and the upgraded CLAS12 detector. In this paper, status of the hall B superconducting magnets for the 12 GeV upgrade is presented.

L. Quettier, V. Burkert, L. Elouadrhiri, D. Kashy, E. Leung, W. Schneider

2011-02-01T23:59:59.000Z

384

Quantum Effect Materials  

Science Conference Proceedings (OSTI)

Measurements were performed using a Fisons V8OH MBE chamber equipped with an "in-line" substrate Manipulator modified to provide optical access to the...

385

NIST Quantum Physics Division - 1998  

Science Conference Proceedings (OSTI)

... QUANTUM PHYSICS DIVISION. Fluorescence Trajectory of a Single 30 Angstrom Radius CdSe Quantum Dot. The quantum ...

386

Intervalley splittings of Si quantum wells  

E-Print Network (OSTI)

Multi-valley effective mass theory for silicon quantum well structure is studied taking into account the external fields and the quantum interfaces. It is found that the phenomenological delta function potential, employed to explain the valley splitting caused by the quantum well interface in the previous work [Ref. 10], can be derived self-consistently from the multi-valley effective mass theory. Finite element method is used to solve the multi-valley effective equations. Theoretical predictions are in a reasonably good agreement with the recent experimental observation of valley splitting in a SiO_{2}/Si/SiO_{2} quantum well, which prove the validity of our approach.

S. -H. Park; Y. Y. Lee; Doyeol Ahn

2007-11-05T23:59:59.000Z

387

Quantum computing  

E-Print Network (OSTI)

This article gives an elementary introduction to quantum computing. It is a draft for a book chapter of the "Handbook of Nature-Inspired and Innovative Computing", Eds. A. Zomaya, G.J. Milburn, J. Dongarra, D. Bader, R. Brent, M. Eshaghian-Wilner, F. Seredynski (Springer, Berlin Heidelberg New York, 2006).

J. Eisert; M. M. Wolf

2004-01-05T23:59:59.000Z

388

Quantum Geometry and Quantum Gravity  

E-Print Network (OSTI)

The purpose of this contribution is to give an introduction to quantum geometry and loop quantum gravity for a wide audience of both physicists and mathematicians. From a physical point of view the emphasis will be on conceptual issues concerning the relationship of the formalism with other more traditional approaches inspired in the treatment of the fundamental interactions in the standard model. Mathematically I will pay special attention to functional analytic issues, the construction of the relevant Hilbert spaces and the definition and properties of geometric operators: areas and volumes.

J. Fernando Barbero G.

2008-04-23T23:59:59.000Z

389

Quantum and Post Quantum Cryptography Abderrahmane Nitaj  

E-Print Network (OSTI)

Quantum and Post Quantum Cryptography Abderrahmane Nitaj Laboratoire de Math´ematiques Nicolas based on quantum mechanics for factoring large integers and computing discrete loga- rithms undermined Gamal and ECC. However, some cryptosystems, called post quantum cryptosystems, while not currently

Nitaj, Abderrahmane

390

QUANTUM STOCHASTIC CALCULUS AND QUANTUM NONLINEAR FILTERING  

E-Print Network (OSTI)

QUANTUM STOCHASTIC CALCULUS AND QUANTUM NONLINEAR FILTERING V. P. BELAVKIN Abstract. A ?­algebraic inde...nite structure of quantum stochastic (QS) cal- culus is introduced and a continuity property...nitely dimensional nuclear space. The class of nondemolition output QS processes in quantum open systems

Belavkin, Viacheslav P.

391

President Obama Talks Clean Energy At Facebook Town Hall | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

President Obama Talks Clean Energy At Facebook Town Hall President Obama Talks Clean Energy At Facebook Town Hall President Obama Talks Clean Energy At Facebook Town Hall April 25, 2011 - 10:24am Addthis Ginny Simmons Ginny Simmons Former Managing Editor for Energy.gov, Office of Public Affairs What does this mean for me? We are investing in new technologies that will help us reduce our dependence on fossil fuels. By investing in STEM education, we are investing in our future. President Obama hosted a town hall at Facebook's headquarters last Wednesday to discuss the direction of our country and the challenges we face. Importantly to us, he highlighted the importance of science education and clean energy innovation throughout the conversation. Check out the video below for President Obama's comments on why investments

392

The $?$-deformed Segal-Bargmann transform is a Hall type transform  

E-Print Network (OSTI)

We present an explanation of how the $\\mu$-deformed Segal-Bargmann spaces, that are studied in various articles of the author in collaboration with Angulo, Echevarria and Pita, can be viewed as deserving their name, that is, how they should be considered as a part of Segal-Bargmann analysis. This explanation relates the $\\mu$-deformed Segal-Bargmann transforms to the generalized Segal-Bargmann transforms introduced by B. Hall using heat kernel analysis. All the versions of the $\\mu$-deformed Segal-Bargmann transform can be understood as Hall type transforms. In particular, we define a $\\mu$-deformation of Hall's "Version C" generalized Segal-Bargmann transform which is then shown to be a $\\mu$-deformed convolution with a $\\mu$-deformed heat kernel followed by analytic continuation. Our results are generalizations and analogues of the results of Hall.

Stephen Bruce Sontz

2007-07-30T23:59:59.000Z

393

Town Hall Meeting August 6th, 2012 | OpenEI Community  

Open Energy Info (EERE)

Town Hall Meeting August 6th, 2012 Town Hall Meeting August 6th, 2012 Home > Groups > OpenEI Community Central Wzeng's picture Submitted by Wzeng(50) Contributor 30 July, 2012 - 14:37 About: OpenEI's town hall meeting is a half-hour open forum for discussions on energy topics. Find out how your fellow researchers, students, teachers and energy professionals are using energy data, maps and tools. When: Occurs every Monday 11:30 AM - 12:00 PM (GMT-07:00) Mountain Time, holidays excluded Please use the following information to call in to this meeting: 866-459-9997 #9645075 Town hall default agenda: 30 minutes 5 mins brief introductions - name, company, potential icebreaker (what's your favorite analysis tool, programming language, energy sector..) Topic will be geothermal related with Geothermal Energy Engineer Kate

394

Performance testing and internal probe measurements of a high specific impulse Hall thruster  

E-Print Network (OSTI)

The BHT-1000 high specific impulse Hall thruster was used for performance testing and internal plasma measurements to support the ongoing development of computational models. The thruster was performance tested in both ...

Warner, Noah Zachary, 1978-

2003-01-01T23:59:59.000Z

395

WIPP Employee Inducted Into Mine Rescue Hall of Fame - WIPP Teams...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Inducted Into Mine Rescue Hall of Fame - WIPP Teams Recognized at National Competition August 2, 2013 - 12:00pm Addthis Waste Isolation Pilot Plant Blue Mine Rescue Team Captain...

396

Is public space still possible? : lessons from City Hall Plaza ideas competition  

E-Print Network (OSTI)

In Autumn, 1994, the City of Boston, in partnership with the Boston Society of Architects and the Building Owners and Managers Association, sponsored the Revitalizing City Hall Plaza Ideas Competition. The Competition ...

Hurley, Timothy C. (Timothy Colyer)

1995-01-01T23:59:59.000Z

397

Hall mobility of cuprous oxide thin films deposited by reactive direct-current magnetron sputtering  

Science Conference Proceedings (OSTI)

Cuprous oxide (Cu{sub 2}O) is a promising earth-abundant semiconductor for photovoltaic applications. We report Hall mobilities of polycrystalline Cu{sub 2}O thin films deposited by reactive dc magnetron sputtering. High substrate growth temperature enhances film grain structure and Hall mobility. Temperature-dependent Hall mobilities measured on these films are comparable to monocrystalline Cu{sub 2}O at temperatures above 250 K, reaching 62 cm{sup 2}/V s at room temperature. At lower temperatures, the Hall mobility appears limited by carrier scattering from ionized centers. These observations indicate that sputtered Cu{sub 2}O films at high substrate growth temperature may be suitable for thin-film photovoltaic applications.

Lee, Yun Seog; Winkler, Mark T.; Siah, Sin Cheng; Brandt, Riley; Buonassisi, Tonio [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2011-05-09T23:59:59.000Z

398

Quantum technology and its applications  

Science Conference Proceedings (OSTI)

Quantum states of matter can be exploited as high performance sensors for measuring time, gravity, rotation, and electromagnetic fields, and quantum states of light provide powerful new tools for imaging and communication. Much attention is being paid to the ultimate limits of this quantum technology. For example, it has already been shown that exotic quantum states can be used to measure or image with higher precision or higher resolution or lower radiated power than any conventional technologies, and proof-of-principle experiments demonstrating measurement precision below the standard quantum limit (shot noise) are just starting to appear. However, quantum technologies have another powerful advantage beyond pure sensing performance that may turn out to be more important in practical applications: the potential for building devices with lower size/weight/power (SWaP) and cost requirements than existing instruments. The organizers of Quantum Technology Applications Workshop (QTAW) have several goals: (1) Bring together sponsors, researchers, engineers and end users to help build a stronger quantum technology community; (2) Identify how quantum systems might improve the performance of practical devices in the near- to mid-term; and (3) Identify applications for which more long term investment is necessary to realize improved performance for realistic applications. To realize these goals, the QTAW II workshop included fifty scientists, engineers, managers and sponsors from academia, national laboratories, government and the private-sector. The agenda included twelve presentations, a panel discussion, several breaks for informal exchanges, and a written survey of participants. Topics included photon sources, optics and detectors, squeezed light, matter waves, atomic clocks and atom magnetometry. Corresponding applications included communication, imaging, optical interferometry, navigation, gravimetry, geodesy, biomagnetism, and explosives detection. Participants considered the physics and engineering of quantum and conventional technologies, and how quantum techniques could (or could not) overcome limitations of conventional systems. They identified several auxiliary technologies that needed to be further developed in order to make quantum technology more accessible. Much of the discussion also focused on specific applications of quantum technology and how to push the technology into broader communities, which would in turn identify new uses of the technology. Since our main interest is practical improvement of devices and techniques, we take a liberal definition of 'quantum technology': a system that utilizes preparation and measurement of a well-defined coherent quantum state. This nomenclature encompasses features broader than entanglement, squeezing or quantum correlations, which are often more difficult to utilize outside of a laboratory environment. Still, some applications discussed in the workshop do take advantage of these 'quantum-enhanced' features. They build on the more established quantum technologies that are amenable to manipulation at the quantum level, such as atom magnetometers and atomic clocks. Understanding and developing those technologies through traditional engineering will clarify where quantum-enhanced features can be used most effectively, in addition to providing end users with improved devices in the near-term.

Boshier, Malcolm [Los Alamos National Laboratory; Berkeland, Dana [USG; Govindan, Tr [ARO; Abo - Shaeer, Jamil [DARPA

2010-12-10T23:59:59.000Z

399

Parity violating quantum kinetic theory in (2+1)-dimensions  

E-Print Network (OSTI)

We study the kinetic theory for a (2+1)-dimensional fermionic system with special emphasis on the parity violating properties associated with the fermion mass. The Wigner function approach is used to derive hydrodynamical transport coefficients to the first spatial derivative order. As a first attempt, the collisions between fermions are neglected. The resulting system is dissipationless. The parity violating Hall electric conductivity has the same temperature and chemical potential dependence as the quantum field theory result at one-loop. Vorticity dependent transport properties, which were not considered before, also emerge naturally in this approach.

Jiunn-Wei Chen; Jian-Hua Gao; Juan Liu; Shi Pu; Qun Wang

2013-05-08T23:59:59.000Z

400

Quantum Walks and Electric Networks  

E-Print Network (OSTI)

We prove that a quantum walk can detect the presence of a marked element in a graph in $O(\\sqrt{WR})$ steps for any initial probability distribution on vertices. Here, $W$ is the total weight of the graph, and $R$ is the effective resistance. This generalizes the result by Szegedy that is only applicable if the initial distribution is stationary. We describe a time-efficient quantum algorithm for 3-distinctness based on these ideas.

Aleksandrs Belovs

2013-02-13T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

LEDS the focus of Monday's 10 a.m. Town Hall Meeting | OpenEI Community  

Open Energy Info (EERE)

LEDS the focus of Monday's 10 a.m. Town Hall Meeting LEDS the focus of Monday's 10 a.m. Town Hall Meeting Home > Blogs > Graham7781's blog Graham7781's picture Submitted by Graham7781(1992) Super contributor 16 November, 2012 - 11:23 LEDS Town Hall meeting What: OpenEI's town hall meeting is a half-hour open forum for discussions on energy topics with NREL's OpenEI team. Find out how your fellow researchers, students, teachers and energy professionals are using energy data, maps and tools. This town hall meeting will focus on the new LEDS Finance Technical Assistance Gateway, or LEAF, being built on OpenEI. After a brief overview of the project, we will open the line to questions, comments and ideas. We will also discuss recent enhancements and near-term objectives for OpenEI. Also, feel free to comment and suggest a topic for the OpenEI Town Hall

402

Quantum Operations and Measurement  

E-Print Network (OSTI)

Quantum Operations and Measurement M.P Seevinck E-mail: M.P.Seevinck@phys.uu.nl Utrecht field in quantum physics ­ or perhaps better, a new way of doing quantum physics ­ . . . Surprisingly of these developments to the conceptual problems of quantum mechanics. In our view, the new work on quantum information

Seevinck, Michiel

403

Quantum Nanomechanics Pritiraj Mohanty  

E-Print Network (OSTI)

Quantum Nanomechanics Pritiraj Mohanty Abstract Quantum Nanomechanics is the emerging field which pertains to the me- chanical behavior of nanoscale systems in the quantum domain. Unlike the conven- tional studies of vibration of molecules and phonons in solids, quantum nanome- chanics is defined as the quantum

404

Quantum Mechanics Measurements, Mutually  

E-Print Network (OSTI)

Quantum Mechanics Measurements, Mutually Unbiased Bases and Finite Geometry Or why six is the first) #12;Quantum Mechanics for Dummies Finite dimensional quantum states are represented by trace one,1 -icS1,1[ ] #12;Quantum systems evolve and are measured. The evolution of a quantum system using

Gruner, Daniel S.

405

Quantum Operations and Measurement  

E-Print Network (OSTI)

Quantum Operations and Measurement # M.P Seevinck # E­mail: M.P.Seevinck@phys.uu.nl Utrecht in quantum physics -- or perhaps better, a new way of doing quantum physics -- . . . Surprisingly, with few to the conceptual problems of quantum mechanics. In our view, the new work on quantum information changes

Seevinck, Michiel

406

Model Theory and Quantum  

E-Print Network (OSTI)

Model Theory and Quantum Groups Sonia L'Innocente Model Theory and Quantum Groups Sonia L'Innocente (University of Mons) Model Theory and Quantum Groups 1 / 40 #12;Model Theory and Quantum Groups Sonia L quantum plane, submitted. This work is inspired by Ivo Herzog's paper: The pseudo-finite dimensional

Mons-Hainaut, Université de

407

Habitat Restoration/Enhancement Fort Hall Reservation : 2008 Annual Report.  

Science Conference Proceedings (OSTI)

Habitat enhancement, protection and monitoring were the focus of the Resident Fisheries Program during 2008. Enhancement and protection included sloping, fencing and planting wetlands plugs at sites on Spring Creek (Head-waters). Many previously constructed instream structures (rock barbs and wing dams) were repaired throughout the Fort Hall Indian Reservation (Reservation). Physical sampling during 2008 included sediment and depth measurements (SADMS) in Spring Creek at the Car Removal site. SADMS, used to track changes in channel morphology and specifically track movements of silt through Bottoms stream systems were completed for 5 strata on Spring Creek. Water temperature and chemistry were monitored monthly on Spring Creek, Clear Creek, Diggie Creek, and Portneuf (Jimmy Drinks) and Blackfoot rivers. Fish population densities and biomass were sampled in five reservation streams which included nine sites. Sampling protocols were identical to methods used in past years. Numbers of fish in Spring Creek series remained relatively low, however, there was an increase of biomass overall since 1993. Salmonid fry densities were monitored near Broncho Bridge and were similar to 2006, and 2007, however, as in years past, high densities of macrophytes make it very difficult to see fry in addition to lack of field technicians. Mean catch rate by anglers on Bottoms streams stayed the same as 2007 at 1.5/hr. Numbers of fish larger than 18-inches caught by anglers increased from 2007 at .20 to .26/hr.

Osborne, Hunter [Shoshone Bannock Tribes

2009-07-23T23:59:59.000Z

408

Quantum Buckling  

E-Print Network (OSTI)

We study the mechanical buckling of a two dimensional membrane coated with a thin layer of superfluid. It is seen that a singularity (vortex or anti-vortex defect) in the phase of the quantum order parameter, distorts the membrane metric into a negative conical singularity surface, irrespective of the defect sign. The defect-curvature coupling and the observed instability is in striking contrast with classical elasticity where, the in-plane strain induced by positive (negative) disclinations is screened by a corresponding positive (negative) conical singularity surface. Defining a dimensionless ratio between superfluid stiffness and membrane bending modulus, we derive conditions under which the quantum buckling instability occurs. An ansatz for the resulting shape of the buckled membrane is analytically and numerically confirmed.

N. Upadhyaya; V. Vitelli

2011-06-23T23:59:59.000Z

409

Quantum gravity and "singularities"  

E-Print Network (OSTI)

The paper concerns the fictitious entanglement of the so-called ``singularities'' in problems, pertaining to quantum gravity, due, in point of fact, to the way we try to employ, in that context, differential geometry, the latter being associated, in effect, by far, classically (:smooth manifolds), on the basis of an erroneous correspondence between what we may call/understand, as ``physical space'' and the ``cartesian-newtonian'' one.

Anastasios Mallios

2004-05-20T23:59:59.000Z

410

CC4, Response of Graphene-Based Field Effect Devices Exposed to ...  

Science Conference Proceedings (OSTI)

Hall effect mobility was evaluated after irradiation, while the response of FET's ..... T6, Electrochemical Graphane Conversion Using E-beam Evaporated Metals...

411

Measurement of Quantum Fluctuations in Geometry  

E-Print Network (OSTI)

A phenomenological calculation is presented of the effect of quantum fluctuations in the spacetime metric, or holographic noise, on interferometeric measurement of the relative positions of freely falling proof masses, in theories where spacetime satisfies covariant entropy bounds and can be represented as a quantum theory on 2+1D null surfaces. The quantum behavior of the 3+1D metric, represented by a commutation relation expressing quantum complementarity between orthogonal position operators, leads to a parameter-free prediction of quantum noise in orthogonal position measurements of freely falling masses. A particular quantum weirdness of this holographic noise is that it only appears in measurements that compare transverse positions, and does not appear at all in purely radial position measurements. The effect on phase signal in an interferometer that continuously measures the difference in the length of orthogonal arms resembles that of a classical random Brownian motion of the beamsplitter with a Planc...

Hogan, Craig J

2007-01-01T23:59:59.000Z

412

A lossy transmission line as a quantum open system in the standard quantum limit  

E-Print Network (OSTI)

We systematically investigate how to quantize a transmission line resonator (TLR) in a mesoscopic electrical circuits in the presence of the resistance and the conductance of the dielectric media. Developed from the quantum bath based effective Hamiltonian method for single mode harmonic oscillator, the approach we presented in this article is a microscopic theory integrating quantum fluctuation-dissipation relation. To qualitatively check the condition under which the TLR can behave as a quantum object we study the classical-quantum boundary characterized by the standard quantum limit.

Y. D. Wang; C. P. Sun

2004-06-30T23:59:59.000Z

413

Quantum Signatures of Spacetime Graininess Quantum Signatures of Spacetime  

E-Print Network (OSTI)

Quantum Signatures of Spacetime Graininess Quantum Signatures of Spacetime "Graininess" Sachindeo September 2009 #12;Quantum Signatures of Spacetime Graininess Introduction 1 Length scales in physics 2 Spacetime noncommutativity from quantum uncertainties 3 Quantum Mechanics on Noncommutative Spacetime 4

414

Quantum Locality?  

Science Conference Proceedings (OSTI)

Robert Griffiths has recently addressed, within the framework of a consistent quantum theory (CQT) that he has developed, the issue of whether, as is often claimed, quantum mechanics entails a need for faster-than-light transfers of information over long distances. He argues, on the basis of his examination of certain arguments that claim to demonstrate the existence of such nonlocal influences, that such influences do not exist. However, his examination was restricted mainly to hidden-variable-based arguments that include in their premises some essentially classical-physics-type assumptions that are fundamentally incompatible with the precepts of quantum physics. One cannot logically prove properties of a system by attributing to the system properties alien to that system. Hence Griffiths rejection of hidden-variable-based proofs is logically warranted. Griffiths mentions the existence of a certain alternative proof that does not involve hidden variables, and that uses only macroscopically described observable properties. He notes that he had examined in his book proofs of this general kind, and concluded that they provide no evidence for nonlocal influences. But he did not examine the particular proof that he cites. An examination of that particular proof by the method specified by his consistent quantum theory shows that the cited proof is valid within that restrictive framework. This necessary existence, within the consistent framework, of long range essentially instantaneous influences refutes the claim made by Griffiths that his consistent framework is superior to the orthodox quantum theory of von Neumann because it does not entail instantaneous influences. An added section responds to Griffiths reply, which cites a litany of ambiguities that seem to restrict, devastatingly, the scope of his CQT formalism, apparently to buttress his claim that my use of that formalism to validate the nonlocality theorem is flawed. But the vagaries that he cites do not upset the proof in question. It is show here in detail why the precise statement of this theorem justifies the specified application of CQT. It is also shown, in response to his challenge, why a putative proof of locality that he has proposed is not valid.

Stapp, Henry

2011-11-10T23:59:59.000Z

415

Quantum limit in continuous quantum measurement  

E-Print Network (OSTI)

The quantum noise is calculated based on the description of imprecise measurement theory, which is used to analyse the general detector's quantum limit in continuous quantum measurement. Different from the traditional description of the linear-response theory, we don't introduce the hypotheses on the properties of the susceptibilities of the detector, and first show a rigorous result: The minimum noise added by the detector in quantum measurement is precisely equal to the zero-point noise. We also discuss the statistic characters of the back-action force in quantum measurement and show how to reach the quantum limit.

Shao, ChengGang

2012-01-01T23:59:59.000Z

416

A magneto-electric quantum wheel  

E-Print Network (OSTI)

Here we show that self-propulsion in quantum vacuum may be achieved by rotating or aggregating magneto-electric nano-particles. The back-action follows from changes in momentum of electro-magnetic zero-point fluctuations, generated in magneto-electric materials. This effect may provide new tools for investigation of the quantum nature of our world. It might also serve in the future as a "quantum wheel" to correct satellite orientation in space.

Alexander Feigel

2009-12-05T23:59:59.000Z

417

A toy model for Macroscopic Quantum Coherence  

E-Print Network (OSTI)

The present article deals with Macroscopic Quantum Coherence resorting only to basic quantum mechanics. A square double well is used to illustrate the Leggett-Caldeira oscillations. The effect of thermal-radiation on two-level systems is discussed to some extent. The concept of decoherence is introduced at an elementary level. Handles are deduced for the energy, temperature and time scales involved in Macroscopic Quantum Coherence.

R. Muoz-Vega; Jos-Job J. Flores-Godoy; G. Fernndez-Anaya; Encarnacin Salinas-Hernndez

2012-10-29T23:59:59.000Z

418

Centrifugal quantum states of neutrons  

E-Print Network (OSTI)

We propose a method for observation of the quasi-stationary states of neutrons, localized near the curved mirror surface. The bounding effective well is formed by the centrifugal potential and the mirror Fermi-potential. This phenomenon is an example of an exactly solvable "quantum bouncer" problem that could be studied experimentally. It could provide a promising tool for studying fundamental neutron-matter interactions, as well as quantum neutron optics and surface physics effects. We develop formalism, which describes quantitatively the neutron motion near the mirror surface. The effects of mirror roughness are taken into account.

V. V. Nesvizhevsky; A. K. Petukhov; K. V. Protasov; A. Yu. Voronin

2008-06-24T23:59:59.000Z

419

Probabilistic bisimulations for quantum processes  

Science Conference Proceedings (OSTI)

Modeling and reasoning about concurrent quantum systems is very important for both distributed quantum computing and quantum protocol verification. As a consequence, a general framework formally describing communication and concurrency in complex quantum ... Keywords: Congruence, Probabilistic bisimulation, Quantum process

Yuan Feng; Runyao Duan; Zhengfeng Ji; Mingsheng Ying

2007-11-01T23:59:59.000Z

420

Quantum Espresso Quick Start Introduction  

E-Print Network (OSTI)

Quantum Espresso Quick Start Introduction Quantum Espresso (http://www.quantum properties eg., phonon dispersion, NMR shifts and band structure to name a few. Quantum Espresso is available. Matter 21, 395502 (2009). Online Guide for QE : http://www.quantum

Bjørnstad, Ottar Nordal

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Quantum Effect Materials: Quantum Dots II - TMS  

Science Conference Proceedings (OSTI)

TMS Logo. About the 1996 Electronic Materials Conference: Friday Afternoon Sessions (June 28). June 26-28, 1996 38TH ELECTRONIC MATERIALS...

422

Dark Energy from Quantum Uncertainty of Simultaneity  

E-Print Network (OSTI)

The observed acceleration expansion of the universe was thought attribute to a mysterious dark energy in the framework of the classical general relativity. The dark energy behaves very similar with a vacuum energy in quantum mechanics. However, once the quantum effects are seriously taken into account, it predicts a wrong order of the vacuum energy and leads to a severe fine-tuning, known as the cosmological constant problem. We abandon the standard interpretation that time is a global parameter in quantum mechanics, replace it by a quantum dynamical variable playing the role of an operational quantum clock system. In the framework of reinterpretation of time, we find that the synchronization of two quantum clocks distance apart can not be realized in all rigor at quantum level. Thus leading to an intrinsic quantum uncertainty of simultaneity between spatial interval, which implies a visional vacuum energy fluctuation and gives an observed dark energy density $\\rho_{de}=\\frac{6}{\\pi}L_{P}^{-2}L_{H}^{-2}$, where $L_{P}$ and $L_{H}$ are the Planck and Hubble scale cut-off. The expectation value of zero-point energy automatically vanishes under the quantum dynamical time variable. The fraction of the dark energy is precisely given by $\\Omega_{de}=\\frac{2}{\\pi}$, which does not evolve with the quantum dynamical time variable, so it is "always" comparable to the matter energy density or the critical density. This theory is consistent with current cosmic observations.

M. J. Luo

2014-01-11T23:59:59.000Z

423

Programmable quantum simulation by dynamic Hamiltonian engineering  

E-Print Network (OSTI)

Quantum simulation is a promising near term application for mesoscale quantum information processors, with the potential to solve computationally intractable problems at the scale of just a few dozen interacting quantum systems. Recent experiments in a range of technical platforms have demonstrated the basic functionality of quantum simulation applied to quantum magnetism, quantum phase transitions, and relativistic quantum mechanics. In all cases, the underlying hardware platforms restrict the achievable inter-particle interaction, forming a serious constraint on the ability to realize a versatile, programmable, quantum simulator. In this work, we address this problem by developing novel sequences of unitary operations that engineer desired effective Hamiltonians in the time-domain. The result is a hybrid programmable analog simulator permitting a broad class of interacting spin-lattice models to be generated starting only with an arbitrary native inter-particle interaction and single-qubit addressing. Building on previous work proving that universal simulation is possible using both entangling gates and single-qubit unitaries, we show how determining the relevant hardware "program" of unitary pulses to implement an arbitrary spin Hamiltonian on such a simulator can be formulated as a linear program that runs in polynomial time and scales efficiently in hardware resources. Our analysis extends from circuit model quantum information to adiabatic quantum evolutions, where our approach allows for the creation of non-native ground state solutions to a computation.

David L. Hayes; Steven T. Flammia; Michael J. Biercuk

2013-09-26T23:59:59.000Z

424

From Quantum Cheating to Quantum Security  

E-Print Network (OSTI)

For thousands of years, code-makers and code-breakers have been competing for supremacy. Their arsenals may soon include a powerful new weapon: quantum mechanics. We give an overview of quantum cryptology as of November 2000.

Daniel Gottesman; Hoi-Kwong Lo

2001-11-19T23:59:59.000Z

425

Correlated wavefunction quantum Monte Carlo approach to solids  

DOE Green Energy (OSTI)

A method for calculating the electronic and structural properties of solids using correlated wavefunctions together with quantum Monte Carlo techniques is described. The approach retains the exact Coulomb interaction between the electrons and employs a many-electron wavefunction of the Jastrow-Slater form. Several examples are given to illustrate the utility of the method. Topics discussed include the cohesive properties of bulk semiconductors, the magnetic-field- induced Wigner crystal in two dimensions, and the magnetic structure of bcc hydrogen. Landau level mixing is shown to be important in determining the transition between the fractional quantum Hall liquid and the Wigner crystal. Information on electron correlations such as the pair correlation functions which are not accessible to one- electron theories is also obtained. 24 refs, 5 figs, 1 tab.

Louie, S.G.

1992-10-01T23:59:59.000Z

426

Quantum Path Interference through Incoherent Motions in Multilevel Quantum Systems  

E-Print Network (OSTI)

Quantum path interferences or resonances in multilevel dissipative quantum systems play an important and intriguing role in the transport processes of nanoscale systems. Many previous minimalistic models used to describe the quantum path interference driven by incoherent fields are based on the approximations including the second order perturbation for the weak coupling limit, the ad-hoc choices of two-time correlation functions and $\\it{etc}$. On the other hand, the similar model to study the non-adiabatic molecular electronic excitation have been extensively developed and many efficient quantum molecular dynamics simulation schemes, such as the Ehrenfest scheme, have been proposed. In this paper, I aim to propose an unified model, extend the Ehrenfest scheme to study the interactions of system-light and system-phonon simultaneously and gain insight into and principles of the roles of quantum path interferences in the realistic molecular systems. I discuss how to derive the time-dependent stochastic Schr$\\ddot{o}$dinger equation from the Ehrenfest scheme as a foundation to discuss the detailed balance for the weak coupling limit and therefore the quantum correction in the Ehrenfest scheme. Different from the master equation technique, the Ehrenfest scheme doesn't need any specific assumptions about spectral densities and two time correlation functions. With simple open two-level and three-level quantum systems, I show the effect of the quantum path interference on the steady state populations. Currently I only focus on the role of the phonon thermal reservoir. The electromagnetic field (solar light) will be modeled as a thermal reservoir and discussed in detail in the future paper.

Xin Chen

2013-05-17T23:59:59.000Z

427

Scalable time reversal of Raman echo quantum memory and quantum waveform conversion of light pulse  

E-Print Network (OSTI)

We have found the new hidden symmetry of time reversal light-atom interaction in the photon echo quantum memory with Raman atomic transition. The time-reversed quantum memory provides generalized condition for ideal compression/decompression of time duration and wavelength conversion of the input light pulse. Based on a general analytical approach to this scheme, we have studied the optimal conditions of the light field compression/decompression in resonant atomic systems characterized by realistic spectral properties. The demonstrated effective quantum conversion of the light waveform and wavelength are also discussed for various possible realizations of the quantum memory scheme. The performed study promises new capabilities for fundamental study of the light-atom interaction and for deterministic quantum manipulation of the light field interested for quantum communication and quantum computing.

Moiseev, E S

2013-01-01T23:59:59.000Z

428

Quantum thermal waves in quantum corrals  

E-Print Network (OSTI)

In this paper the possibility of the generation of the thermal waves in 2D electron gas is investigated. In the frame of the quantum heat transport theory the 2D quantum hyperbolic heat transfer equation is formulated and numerically solved. The obtained solutions are the thermal waves in electron 2D gases. As an exapmle the thermal waves in quantum corrals are described. Key words: 2D electron gas, quantum corrals, thermal waves.

J. Marciak-Kozlowska; M. Kozlowski

2004-05-07T23:59:59.000Z

429

Drift solitons and shocks in inhomogeneous quantum magnetoplasmas  

Science Conference Proceedings (OSTI)

Linear and nonlinear drift waves are studied in inhomogeneous electron-ion quantum magnetoplasma with neutrals in the background. The Korteweg-de Vries-Burgers equation is derived by using the quantum hydrodynamic model for nonlinear drift waves with quantum corrections. Both soliton and shock solutions are obtained in different limits. It is noticed that the width of the solitary hump is decreased with the increase in the quantum parameter. However this effect is reversed for the solitary dip case. It is also found that oscillatory shock wave is dependent on the quantum parameter. However, the monotonic shock formation is independent of the quantum parameter.

Haque, Q.; Mahmood, S. [Theoretical Plasma Physics Division, Pakistan Institute of Nuclear Science and Technology, P.O. Nilore, Islamabad, 45320 (Pakistan)

2008-03-15T23:59:59.000Z

430

Improving Ranking Using Quantum Probability  

E-Print Network (OSTI)

The paper shows that ranking information units by quantum probability differs from ranking them by classical probability provided the same data used for parameter estimation. As probability of detection (also known as recall or power) and probability of false alarm (also known as fallout or size) measure the quality of ranking, we point out and show that ranking by quantum probability yields higher probability of detection than ranking by classical probability provided a given probability of false alarm and the same parameter estimation data. As quantum probability provided more effective detectors than classical probability within other domains that data management, we conjecture that, the system that can implement subspace-based detectors shall be more effective than a system which implements a set-based detectors, the effectiveness being calculated as expected recall estimated over the probability of detection and expected fallout estimated over the probability of false alarm.

Melucci, Massimo

2011-01-01T23:59:59.000Z

431

An environment-mediated quantum deleter  

E-Print Network (OSTI)

Environment-induced decoherence presents a great challenge to realizing a quantum computer. We point out the somewhat surprising fact that decoherence can be useful, indeed necessary, for practical quantum computation, in particular, for the effective erasure of quantum memory in order to initialize the state of the quantum computer. The essential point behind the deleter is that the environment, by means of a dissipative interaction, furnishes a contractive map towards a pure state. We present a specific example of an amplitude damping channel provided by a two-level system's interaction with its environment in the weak Born-Markov approximation. This is contrasted with a purely dephasing, non-dissipative channel provided by a two-level system's interaction with its environment by means of a quantum nondemolition interaction. We point out that currently used state preparation techniques, for example using optical pumping, essentially perform as quantum deleters.

R. Srikanth; Subhashish Banerjee

2006-11-27T23:59:59.000Z

432

Quantum Dimensions and Quantum Galois Theory  

E-Print Network (OSTI)

The quantum dimensions of modules for vertex operator algebras are defined and their properties are discussed. The possible values of the quantum dimensions are obtained for rational vertex operator algebras. A criterion for simple currents of a rational vertex operator algebra is given. A full Galois theory for rational vertex operator algebras is established using the quantum dimensions.

Dong, Chongying; Xu, Feng

2012-01-01T23:59:59.000Z

433

The evolution of the structure of quantum size effect Pb nanocrystals on Si(111) 7x7  

SciTech Connect

We have carried out diffuse X-ray scattering measurements of the growth of Pb nanocrystalline islands on Si(1 1 1). Analysis of our data shows that islands growing on an initially rough wetting layer transforms the portion of the wetting layer below them into ordered fcc sites. Therefore, the islands grow directly on top of the Si surface with a disordered wetting layer occupying the region between the islands and, consequently, the island height responsible for the quantum well depth is one layer thicker than reported by LEED and STM. These islands have an extremely good vertical order until the islands coalesce into a closed film. At that point the disorder of the film increases consistent with misfit strain relaxation.

Feng, R.; Conrad, E.H.; Kim, C.; Miceli, P.F.; Tringides, M.C. (ISU); (GIT); (UMC)

2010-07-13T23:59:59.000Z

434

Quantum information in a nutshell () Quantum mechanics + information science  

E-Print Network (OSTI)

Quantum information in a nutshell (?²¤¶) Quantum mechanics + information science = quantum information science = quantum information transfer + quantum algorithm (software) + quantum computer (hardware) + quantum simulation +... = a field rapidly growing in the last 10 years ®v½d¤j¾?ª«²z¨t ±i©ú-õ #12;Brief

Chang, Ming-Che

435

Applied Quantum Information Science  

Science Conference Proceedings (OSTI)

Applied Quantum Information Science. Summary: Theory is being developed and used to devise methods for preserving ...

2012-05-30T23:59:59.000Z

436

Quantum Dating Market  

E-Print Network (OSTI)

We consider the dating market decision problem under the quantum mechanics point of view. Quantum states whose associated amplitudes are modified by men strategies are used to represent women. Grover quantum search algorithm is used as a playing strategy. Success is more frequently obtained by playing quantum than playing classic.

O. G. Zabaleta; C. M. Arizmendi

2010-03-04T23:59:59.000Z

437

Quantum Dots Executive Overview  

E-Print Network (OSTI)

Quantum Dot Sol-Gel Nanocomposites (patent pending) n Nanocrystal Quantum Dot Light Emitting Diode (patent (CRADA) Business Opportunities LANL's quantum dot portfolio includes a high-efficiency light emitting diode (LED) design based on non-radiative energy transfer from a quantum well into a layer of colloidal

438

Ergodic Quantum Computing  

Science Conference Proceedings (OSTI)

We propose a (theoretical) model for quantum computation where the result can be read out from the time average of the Hamiltonian dynamics of a 2-dimensional crystal on a cylinder.The Hamiltonian is a spatially local interaction among Wigner--Seitz ... Keywords: Hamiltonian of a quantum computer, Quantum cellular automata, solid state quantum computing, thermodynamics of computation

Dominik Janzing; Pawel Wocjan

2005-06-01T23:59:59.000Z

439

Quantum chaology Michael Berry  

E-Print Network (OSTI)

1 Quantum chaology Michael Berry Physics Department, University of Bristol Physics pp104-5 of Quantum: a guide for the perplexed by Jim Al-Khalili (Weidenfeld and Nicolson 2003) The quantum world appears very different from the world of classical physics that it superseded. Quantum energy levels

Berry, Michael Victor

440

QUANTUM GROUPS JOHAN KUSTERMANS  

E-Print Network (OSTI)

QUANTUM GROUPS JOHAN KUSTERMANS Syllabus: #15; The de#12;nition of a locally compact quantum group: motivational ex- amples and special cases. The classical case, compact and discrete quantum groups. #15 for weights. #15; The general de#12;nition of a locally compact quantum group and its basic consequences

Schürmann, Michael

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Quantum Statistics Madalin Guta  

E-Print Network (OSTI)

Quantum Statistics Madalin Gut¸a School of Mathematics University of Nottingham 1 #12;The old paradigm Quantum Mechanics up to the 80's Quantum measurements have random results Only probability particles, any more than we can raise Ichtyosauria in the zoo 2 #12;The new paradigm Individual quantum

Guta, Madalin

442

Quantum Walks Norio Konno  

E-Print Network (OSTI)

Quantum Walks Norio Konno Yokohama National University Two types of quantum (random) walks, discrete-time (coined) or continuous- time, were introduced as the quantum mechanical extension of the corresponding classical random walks in connection with quantum computing and have been extensively studied over

Schürmann, Michael

443

Quantum Algorithms for Quantum Field Theories  

E-Print Network (OSTI)

Quantum field theory reconciles quantum mechanics and special relativity, and plays a central role in many areas of physics. We develop a quantum algorithm to compute relativistic scattering probabilities in a massive quantum field theory with quartic self-interactions (phi-fourth theory) in spacetime of four and fewer dimensions. Its run time is polynomial in the number of particles, their energy, and the desired precision, and applies at both weak and strong coupling. In the strong-coupling and high-precision regimes, our quantum algorithm achieves exponential speedup over the fastest known classical algorithm.

Stephen P. Jordan; Keith S. M. Lee; John Preskill

2011-11-15T23:59:59.000Z

444

Quantum Algorithms for Quantum Field Theories  

E-Print Network (OSTI)

Quantum field theory reconciles quantum mechanics and special relativity, and plays a central role in many areas of physics. We develop a quantum algorithm to compute relativistic scattering probabilities in a massive quantum field theory with quartic self-interactions (phi-fourth theory) in spacetime of four and fewer dimensions. Its run time is polynomial in the number of particles, their energy, and the desired precision, and applies at both weak and strong coupling. In the strong-coupling and high-precision regimes, our quantum algorithm achieves exponential speedup over the fastest known classical algorithm.

Jordan, Stephen P; Preskill, John

2011-01-01T23:59:59.000Z

445

Quantum discord and Markovianity of quantum dynamics  

E-Print Network (OSTI)

The problem of recognizing (non-)Markovianity of a quantum dynamics is revisited through analyzing quan- tum correlations. We argue that instantaneously-vanishing quantum discord provides a necessary and sufficient condition for Markovianity of a quantum map. This is used to introduce a measure of non-Markovianity. This measure, however, requires demanding knowledge about the system and the environment. By using a quantum correlation monogamy property and an ancillary system, we propose a simplified measure with less require- ments. Non-Markovianity is thereby decided by quantum state tomography of the system and the ancilla.

Alipour, S

2012-01-01T23:59:59.000Z

446

Quantum Monte Carlo simulations of solids W. M. C. Foulkes  

E-Print Network (OSTI)

Quantum Monte Carlo simulations of solids W. M. C. Foulkes CMTH Group, Department of Physics and fixed-node diffusion quantum Monte Carlo methods and how they may be used to calculate the properties of quantum many-body effects and serve as benchmarks against which other techniques may be compared

Wu, Zhigang

447

Town Hall Meeting July 9th, 2012 | OpenEI Community  

Open Energy Info (EERE)

Town Hall Meeting July 9th, 2012 Town Hall Meeting July 9th, 2012 Home > Groups > Utility Rate Rmckeel's picture Submitted by Rmckeel(297) Contributor 2 July, 2012 - 14:33 This week's focus will have Dr Dave Loomis and others of Illinois State University discussing utility rates on OpenEI! When: Occurs every Monday 11:30 AM - 12:00 PM (GMT-07:00) Mountain Time, holidays excluded Please use the following information to call in to this meeting: 866-459-9997 #9645075 Town hall default agenda: 30 minutes 5 mins brief introductions - name, company, potential icebreaker (what's your favorite analysis tool, programming language, energy sector..) Topic focus for July 9: Discussion of utility rates on OpenEI, curation process, APIs, etc Date: Monday, 9 July, 2012 - 11:30 - 12:00 Location: 866-459-9997 #9645075

448

Town Hall Meeting July 23th, 2012 | OpenEI Community  

Open Energy Info (EERE)

Town Hall Meeting July 23th, 2012 Town Hall Meeting July 23th, 2012 Home > Groups > OpenEI Community Central Wzeng's picture Submitted by Wzeng(50) Contributor 16 July, 2012 - 15:27 This week's focus is on user feedback on OpenEI. When: Occurs every Monday 11:30 AM - 12:00 PM (GMT-07:00) Mountain Time, holidays excluded Please use the following information to call in to this meeting: 866-459-9997 #9645075 Town hall default agenda: 30 minutes 5 mins brief introductions - name, company, potential icebreaker (what's your favorite analysis tool, programming language, energy sector..) Topic will be user feedback on OpenEI. Please join to speak with the OpenEI Team and discuss your thoughts, opinions, and complaints about the wiki! Date: Monday, 23 July, 2012 - 11:30 - 12:00 Location: 866-459-9997 #9645075

449

Town Hall Meeting October 1st, 2012 | OpenEI Community  

Open Energy Info (EERE)

49 49 Varnish cache server Home Groups Community Central Green Button Applications Developer Utility Rate FRED: FRee Energy Database More Public Groups Private Groups Features Groups Blog posts Content Stream Documents Discussions Polls Q & A Events Notices My stuff Energy blogs 429 Throttled (bot load) Error 429 Throttled (bot load) Throttled (bot load) Guru Meditation: XID: 2142234349 Varnish cache server Town Hall Meeting October 1st, 2012 Home > Blogs > Graham7781's blog Graham7781's picture Submitted by Graham7781(2002) Super contributor 19 September, 2012 - 13:40 OpenEI Town Hall meeting What: OpenEI's town hall meeting is a half-hour open forum for discussions on energy topics with NREL's OpenEI team. Find out how your fellow researchers, students, teachers and energy professionals are using energy

450

Operation of a Segmented Hall Thruster with Low-sputtering Carbon-velvet Electrodes  

Science Conference Proceedings (OSTI)

Carbon fiber velvet material provides exceptional sputtering resistance properties exceeding those for graphite and carbon composite materials. A 2 kW Hall thruster with segmented electrodes made of this material was operated in the discharge voltage range of 200700 V. The arcing between the floating velvet electrodes and the plasma was visually observed, especially, during the initial conditioning time, which lasted for about 1 h. The comparison of voltage versus current and plume characteristics of the Hall thruster with and without segmented electrodes indicates that the magnetic insulation of the segmented thruster improves with the discharge voltage at a fixed magnetic field. The observations reported here also extend the regimes wherein the segmented Hall thruster can have a narrower plume than that of the conventional nonsegmented thruster.

Raitses, Y.; Staack, D.; Dunaevsky, A.; Fisch, N.J.

2005-12-01T23:59:59.000Z

451

Multiscaling in Hall-Magnetohydrodynamic Turbulence: Insights from a Shell Model  

E-Print Network (OSTI)

We show that a shell-model version of the three-dimensional Hall-magnetohydrodynamic (3D Hall-MHD) equations provides a natural theoretical model for investigating the multiscaling behaviors of velocity and magnetic structure functions. We carry out extensive numerical studies of this shell model, obtain the scaling exponents for its structure functions, in both the low-$k$ and high-$k$ power-law ranges of 3D Hall-MHD, and find that the extended-self-similarity (ESS) procedure is helpful in extracting the multiscaling nature of structure functions in the high-$k$ regime, which otherwise appears to display simple scaling. Our results shed light on intriguing solar-wind measurements.

Debarghya Banerjee; Samriddhi Sankar Ray; Ganapati Sahoo; Rahul Pandit

2013-03-04T23:59:59.000Z

452

LANL | Physics | Quantum Information  

NLE Websites -- All DOE Office Websites (Extended Search)

Breakthrough quantum information Breakthrough quantum information science and technology Physics Division's quantum information science and technology capability supports present and future Laboratory missions in cyber-security, sensing, nonproliferation, information science, and materials. Collaborating with researchers throughout Los Alamos and leading institutions in the nation, Physics Division scientists are involved in projects in quantum communications, including quantum key distribution and quantum-enabled security and networking, and in quantum cold-atom physics. Recent fundamental science results include the ability to "paint" potentials that can trap Bose-Einstein condensates into geometric forms, such as the toroidal ring of clusters, the density of which is measured in

453

Quantum extended crystal PDE's  

E-Print Network (OSTI)

Our recent results on {\\em extended crystal PDE's} are generalized to PDE's in the category $\\mathfrak{Q}_S$ of quantum supermanifolds. Then obstructions to the existence of global quantum smooth solutions for such equations are obtained, by using algebraic topologic techniques. Applications are considered in details to the quantum super Yang-Mills equations. Furthermore, our geometric theory of stability of PDE's and their solutions, is also generalized to quantum extended crystal PDE's. In this way we are able to identify quantum equations where their global solutions are stable at finite times. These results, are also extended to quantum singular (super)PDE's, introducing ({\\em quantum extended crystal singular (super) PDE's}).

Agostino Prstaro

2011-05-01T23:59:59.000Z

454

Quantum Computational Complexity John Watrous  

E-Print Network (OSTI)

Quantum Computational Complexity John Watrous Institute for Quantum Computing and School of the subject and its importance II. Introduction III. The quantum circuit model IV. Polynomial-time quantum computations V. Quantum proofs VI. Quantum interactive proof systems VII. Other selected notions in quantum

Watrous, John

455

Quantum optical waveform conversion  

E-Print Network (OSTI)

Currently proposed architectures for long-distance quantum communication rely on networks of quantum processors connected by optical communications channels [1,2]. The key resource for such networks is the entanglement of matter-based quantum systems with quantum optical fields for information transmission. The optical interaction bandwidth of these material systems is a tiny fraction of that available for optical communication, and the temporal shape of the quantum optical output pulse is often poorly suited for long-distance transmission. Here we demonstrate that nonlinear mixing of a quantum light pulse with a spectrally tailored classical field can compress the quantum pulse by more than a factor of 100 and flexibly reshape its temporal waveform, while preserving all quantum properties, including entanglement. Waveform conversion can be used with heralded arrays of quantum light emitters to enable quantum communication at the full data rate of optical telecommunications.

Kielpinski, D; Wiseman, HM

2010-01-01T23:59:59.000Z

456

Quantum Ice : a quantum Monte Carlo study  

E-Print Network (OSTI)

Ice states, in which frustrated interactions lead to a macroscopic ground-state degeneracy, occur in water ice, in problems of frustrated charge order on the pyrochlore lattice, and in the family of rare-earth magnets collectively known as spin ice. Of particular interest at the moment are "quantum spin ice" materials, where large quantum fluctuations may permit tunnelling between a macroscopic number of different classical ground states. Here we use zero-temperature quantum Monte Carlo simulations to show how such tunnelling can lift the degeneracy of a spin or charge ice, stabilising a unique "quantum ice" ground state --- a quantum liquid with excitations described by the Maxwell action of 3+1-dimensional quantum electrodynamics. We further identify a competing ordered "squiggle" state, and show how both squiggle and quantum ice states might be distinguished in neutron scattering experiments on a spin ice material.

Nic Shannon; Olga Sikora; Frank Pollmann; Karlo Penc; Peter Fulde

2011-05-20T23:59:59.000Z

457

Potential contour shaping and sheath behavior with wall electrodes and near-wall magnetic fields in Hall thrusters  

SciTech Connect

Graphite electrodes are embedded within the discharge channel of a Hall effect thruster to focus ions for improved performance. Cusp-shaped magnetic fields are added around the electrodes to shield the electrodes from high electron current. Internal plasma potential measurements inside the discharge channel show that the presence of floating graphite does not significantly affect the potential contours at 150 V anode potential. Creation of closed contour pockets are observed with the electrodes biased 10 and 30 V above the anode potential. The electrodes also cause a compression of the acceleration region in the thruster. The cause of the changes in the potential contours is attributed to a shifting of discharge electrode from the anode to the electrodes and an expansion of the near-wall plasma sheath. The presence of the cusp magnetic fields is shown to affect the current collected by the electrodes, a behavior associated with modification of the plasma sheath properties due to magnetization of electrons.

Xu, K. G. [Department of Mechanical and Aerospace Engineering, University of Alabama in Huntsville, Huntsville, Alabama 35899 (United States); Dao, H.; Walker, M. L. R. [Department of Aerospace Engineering, Georgia Institute of Technology, Atlanta, Georgia 30318 (United States)

2012-10-15T23:59:59.000Z

458

Building America Top Innovations Hall of Fame Profile … Reduced Call-Backs with High-Performance Production Builders  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

When Grupe of Stockton, California, worked When Grupe of Stockton, California, worked with Building America to build 144 energy- efficient homes in its Carsten Crossings development, the site superintendent said he had the lowest call-back rate of any community he had worked on. He credited the third-party HERS inspections and testing for keeping the quality of work high and catching problems before move-in (Dakin et al. 2008). BUILDING AMERICA TOP INNOVATIONS HALL OF FAME PROFILE INNOVATIONS CATEGORY: 2. House-as-a-System Solutions 2.1 New Homes with Whole-House Packages Reduced Call-Backs with High-Performance Production Builders It is essential to engage production builders to successfully transform the market to high-performance homes. Building America has effectively addressed this

459

High precision measurements of the neutron spin structure in Hall A at Jlab  

SciTech Connect

Conclusions of this presentation are: (1) JLab energy upgrade will offer new exciting opportunities to study the nucleon (spin) structure such as high precision, unexplored phase space, flavor decomposition; (2) Large technological efforts is in progress to optimally exploit these opportunities; (3) HallA will be the first hall to get the new beam, first experiment expected to run in 2014; (4) A1n likely one of the first experiments to take data in the new 12 GeV era; and (5) SIDIS exp. will follow in couple of years.

Annand, R M; Cates, G; Cisbani, E; Franklin, G B; Liyanage, N; Puckett, A; Rosner, G; Wojtsekhowski, B

2012-04-01T23:59:59.000Z

460

Physics as Quantum Information Processing: Quantum Fields as Quantum Automata 1  

E-Print Network (OSTI)

Physics as Quantum Information Processing: Quantum Fields as Quantum Automata 1 Giacomo Mauro D Nazionale di Fisica Nucleare, Gruppo IV, Sezione di Pavia Abstract. Can we reduce Quantum Field Theory (QFT) to a quantum computation? Can physics be simulated by a quantum computer? Do we believe that a quantum field

D'Ariano, Giacomo Mauro

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Laser irradiation effects on the CdTe/ZnTe quantum dot structure studied by Raman and AFM spectroscopy  

SciTech Connect

Micro-Raman spectroscopy has been applied to investigate the impact of laser irradiation on semiconducting CdTe/ZnTe quantum dots (QDs) structures. A reference sample (without dots) was also studied for comparison. Both samples were grown by molecular beam epitaxy technique on the p-type GaAs substrate. The Raman spectra have been recorded for different time of a laser exposure and for various laser powers. The spectra for both samples exhibit peak related to the localized longitudinal (LO) ZnTe phonon of a wavenumber equal to 210 cm{sup -1}. For the QD sample, a broad band corresponding to the LO CdTe phonon related to the QD-layer appears at a wavenumber of 160 cm{sup -1}. With increasing time of a laser beam exposure and laser power, the spectra get dominated by tellurium-related peaks appearing at wavenumbers around 120 cm{sup -1} and 140 cm{sup -1}. Simultaneously, the ZnTe surface undergoes rising damage, with the formation of Te aggregates at the pinhole edge as reveal atomic force microscopy observations. Local temperature of irradiated region has been estimated from the anti-Stokes/Stokes ratio of the Te modes intensity and it was found to be close or exceeding ZnTe melting point. Thus, the laser damage can be explained by the ablation process.

Zielony, E.; Placzek-Popko, E.; Henrykowski, A.; Gumienny, Z.; Kamyczek, P.; Jacak, J. [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Nowakowski, P.; Karczewski, G. [Institute of Physics, Polish Academy of Sciences, al. Lotnikow 32/46, 02-668 Warsaw (Poland)

2012-09-15T23:59:59.000Z

462

Ultrafast Supercontinuum Spectroscopy of Carrier Multiplication and Biexcitonic Effects in Excited States of PbS Quantum Dots  

SciTech Connect

We examine the population dynamics of multiple excitons in PbS quantum dots using spectrally resolved ultrafast supercontinuum transient absorption (SC-TA) measurements. We simultaneously probe the first three excitonic transitions. The transient spectra show the presence of bleaching of absorption for the 1S{sub h}-1S{sub e} transition, as well as transients associated with the 1P{sub h}-1P{sub e} transition. We examine signatures of carrier multiplication (multiple excitons arising from a single absorbed photon) from analysis of the bleaching features in the limit of low absorbed photon numbers (

Sfeir M. Y.; Gesuele, F.; Koh, W.-K.; Murray, C.B.; Heinz, T.F.; Wong, C.W.

2012-06-01T23:59:59.000Z

463

Theoretical study of quantum molecular reaction dynamics and of the effects of intense laser radiation on a diatomic molecule  

DOE Green Energy (OSTI)

Within the very broad field of molecular dynamics, we have concentrated on two simple yet important systems. The systems are simple enough so that they are adequately described with a single Born-Oppenheimer potential energy surface and that the dynamics can be calculated accurately. They are important because they give insight into solving more complicated systems. First we discuss H + H/sub 2/ reactive scattering. We present an exact formalism for atom-diatom reactive scattering which avoids the problem of finding a coordinate system appropriate for both reactants and products. We present computational results for collinear H + H/sub 2/ reactive scattering which agree very well with previous calculations. We also present a coupled channel distorted wave Born approximation for atom-diatom reactive scattering which we show is a first order approximation to our exact formalism. We present coupled channel DWBA results for three dimensional H + H/sub 2/ reactive scattering. The second system is an isolated HF molecule in an intense laser field. Using classical trajectories and quantum dynamics, we look at energy absorbed and transition probabilities as a function of the laser pulse time and also averaged over the pulse time. Calculations are performed for both rotating and nonrotating HF. We examine one and two photon absorption about the fundamental frequency, multiphoton absorption, and overtone absorption. 127 references, 31 figures, 12 tables.

Dardi, P.S.

1984-11-01T23:59:59.000Z

464

Quantum Noise and Information in Quantum Search Algorithm  

Science Conference Proceedings (OSTI)

External influences in the form of quantum noise on Grovers search algorithm are investigated. The study shows that the algorithm can be robust under such external dissipation. The effect of noise is described by a completely positive trace preserving map

D. Ellinas; Ch. Konstandakis

2004-01-01T23:59:59.000Z

465

On kinetic description of electromagnetic processes in a quantum plasma  

E-Print Network (OSTI)

A nonlinear kinetic equation for nonrelativistic quantum plasma with electromagnetic interaction of particles is obtained in the Hartree's mean-field approximation. It is cast in a convenient form of Vlasov-Boltzmann-type equation with "quantum interference integral", that allows for relatively straightforward modification of existing classical Vlasov codes to incorporate quantum effects (quantum statistics and quantum interference of overlapping particles wave functions), without changing the bulk of the codes. Such modification (upgrade) of existing Vlasov codes may provide a direct and effective path to numerical simulations of nonlinear electrostatic and electromagnetic phenomena in quantum plasmas, especially of processes where kinetic effects are important (e.g., modulational interactions and stimulated scattering phenomena involving plasma modes at short wavelengths or high-order kinetic modes, dynamical screening and interaction of charges in quantum plasma, etc.) Moreover, numerical approaches involv...

Tyshetskiy, Y O; Kompaneets, R

2011-01-01T23:59:59.000Z

466

IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 55, NO. 6, DECEMBER 2008 3633 Radiation Effects on InGaN Quantum Wells  

E-Print Network (OSTI)

GaN Quantum Wells and GaN Simultaneously Probed by Ion Beam-Induced Luminescence J. W. Tringe, Member, IEEE, A. Stevens, and C. Wetzel, Member, IEEE Abstract--InGaN quantum well structures on GaN epilayers were exposed of the epilayer and wells. Performance was estimated by the intensity of ion-beam induced luminescence. Two

Wetzel, Christian M.

467

Optical Modulator on Si Employing Ge Quantum Wells Jonathan E. Roth1*  

E-Print Network (OSTI)

Optical Modulator on Si Employing Ge Quantum Wells Jonathan E. Roth1* , Onur Fidaner1 , Rebecca K ; (230.5590) Quantum-well devices The recently demonstrated quantum confined Stark effect (QCSE) in germanium quantum wells is a likely candidate for creating optoelectronic modulators for monolithically

Miller, David A. B.

468

Power loss of an oscillating electric dipole in a quantum plasma  

Science Conference Proceedings (OSTI)

A system of linearized quantum plasma equations (quantum hydrodynamic model) has been used for investigating the dispersion equation for electrostatic waves in the plasma. Furthermore, dispersion relations and their modifications due to quantum effects are used for calculating the power loss of an oscillating electric dipole. Finally, the results are compared in quantum and classical regimes.

Ghaderipoor, L. [Department of Physics, Faculty of Science, University of Qom, 3716146611 (Iran, Islamic Republic of); Mehramiz, A. [Department of Physics, Faculty of Science, Imam Khomeini Int'l University, Qazvin 34149-16818 (Iran, Islamic Republic of)

2012-12-15T23:59:59.000Z

469

Geometrical perspective on quantum states and quantum computation  

E-Print Network (OSTI)

We interpret quantum computing as a geometric evolution process by reformulating finite quantum systems via Connes' noncommutative geometry. In this formulation, quantum states are represented as noncommutative connections, while gauge transformations on the connections play a role of unitary quantum operations. Thereby, a geometrical model for quantum computation is presented, which is equivalent to the quantum circuit model. This result shows a geometric way of realizing quantum computing and as such, provides an alternative proposal of building a quantum computer.

Zeqian Chen

2013-11-20T23:59:59.000Z

470

Quantum Electrodynamics for Vector Mesons  

Science Conference Proceedings (OSTI)

Quantum electrodynamics for {rho} mesons is considered. It is shown that, at the tree level, the value of the gyromagnetic ratio of the {rho}{sup +} is fixed to 2 in a self-consistent effective quantum field theory. Further, the mixing parameter of the photon and the neutral vector meson is equal to the ratio of electromagnetic and strong couplings, leading to the mass difference M{sub {rho}}{sub {sup 0}}-M{sub {rho}}{sub {sup {+-}}}{approx}1 MeV at tree order.

Djukanovic, Dalibor; Schindler, Matthias R.; Scherer, Stefan [Institut fuer Kernphysik, Johannes Gutenberg-Universitaet, 55099 Mainz (Germany); Gegelia, Jambul [Institut fuer Kernphysik, Johannes Gutenberg-Universitaet, 55099 Mainz (Germany); High Energy Physics Institute, Tbilisi State University, Tbilisi (Georgia)

2005-07-01T23:59:59.000Z

471

Conservation Subdivision Survey Data Collection: Erica Christoph, Kenna Hall, Amy Salley  

E-Print Network (OSTI)

Conservation Subdivision Survey Data Collection: Erica Christoph, Kenna Hall, Amy Salley Data conservation subdivisions in Georgia and prepared a report updating information from a survey completed several years ago. Members compiled a list of developers of conservation subdivisions and telephoned them asking

Radcliffe, David

472

Reconstructing the music hall rotunda and annex at vauxhall pleasure gardens c. 1764  

Science Conference Proceedings (OSTI)

This paper summarises work in progress on the digital reconstruction of the structure, space and decorative program of the music hall and annex at Vauxhall Pleasure Gardens c. 1764. The proposed outcome will be a recreation of the space and its contents ... Keywords: animation, gallery display, historic sites, music, reconstructive architecture, visualisation

Stephen Caffey; Robert G. Graf; Charles Culp; Wei Yan; Ehsan Barekati; Matthew Marshall

2010-07-01T23:59:59.000Z

473

HIGH ACCURACY BEAM CURRENT MONITOR SYSTEM FOR CEBAF'S EXPERIMENTAL HALL A *  

E-Print Network (OSTI)

HIGH ACCURACY BEAM CURRENT MONITOR SYSTEM FOR CEBAF'S EXPERIMENTAL HALL A * J.-C. Denard , A. Saha, Université Blaise Pascal IN2P3-CNRS Abstract CEBAF accelerator delivers continuous wave (CW) electron beams for measuring accurately the linearity is described. 1 INTRODUCTION The CEBAF accelerator delivers continuous

Paris-Sud XI, Université de

474

High performance computing and the simplex method Julian Hall, Qi Huangfu and Edmund Smith  

E-Print Network (OSTI)

High performance computing and the simplex method Julian Hall, Qi Huangfu and Edmund Smith School of Mathematics University of Edinburgh 12th April 2011 High performance computing and the simplex method #12;The... ... but methods for all three depend on it! High performance computing and the simplex method 1 #12;Overview · LP

Hall, Julian

475

Diagnostic Setup for Characterization of Near-Anode Processes in Hall Thrusters  

DOE Green Energy (OSTI)

A diagnostic setup for characterization of the near-anode processes in Hall thrusters was designed and assembled. Experimental results with a single floating probe show that radial probe insertion does not cause perturbations to the discharge and therefore can be used for near-anode measurements.

L. Dorf; Y. Raitses; N. J. Fisch

2003-05-29T23:59:59.000Z

476

Neogene sutures in eastern Indonesia R. Hall*, M.E.J. Wilson1  

E-Print Network (OSTI)

Neogene sutures in eastern Indonesia R. Hall*, M.E.J. Wilson1 SE Asia Research Group, Department the Eurasian, Indian­Australian and Pacific­Philippine Sea plates within the eastern Indonesia region Indonesia; Tectonic changes 1. Introduction Eastern Indonesia is situated at the junction of three major

Royal Holloway, University of London

477

Quantum Indeterminacy of Emergent Spacetime  

E-Print Network (OSTI)

It is shown that nearly-flat 3+1D spacetime emerging from a dual quantum field theory in 2+1D displays quantum fluctuations from classical Euclidean geometry on macroscopic scales. A covariant holographic mapping is assumed, where plane wave states with wavevector k on a 2D surface map onto classical null trajectories in the emergent third dimension at an angle \\theta=l_P k relative to the surface element normal, where l_P denotes the Planck length. Null trajectories in the 3+1D world then display quantum uncertainty of angular orientation, with standard deviation \\Delta\\theta=\\sqrt{l_P/z} for longitudinal propagation distance z in a given frame. The quantum complementarity of transverse position at macroscopically separated events along null trajectories corresponds to a geometry that is not completely classical, but displays observable holographic quantum noise. A statistical estimator of the fluctuations from Euclidean behavior is given for a simple thought experiment based on measured sides of triangles. The effect can be viewed as sampling noise due to the limited degrees of freedom of such a theory, consistent with covariant bounds on entropy.

Craig J. Hogan

2007-10-22T23:59:59.000Z

478

Quantum benchmarks for Gaussian states  

E-Print Network (OSTI)

Teleportation and storage of continuous variable states of light and atoms are essential building blocks for the realization of large scale quantum networks. Rigorous validation of these implementations require identifying, and surpassing, benchmarks set by the most effective strategies attainable without the use of quantum resources. Such benchmarks have been established for special families of input states, like coherent states and particular subclasses of squeezed states. Here we solve the longstanding problem of defining quantum benchmarks for general pure Gaussian states with arbitrary phase, displacement, and squeezing, randomly sampled according to a realistic prior distribution. As a special case, we show that the fidelity benchmark for teleporting squeezed states with totally random phase and squeezing degree is 1/2, equal to the corresponding one for coherent states. We discuss the use of entangled resources to beat the benchmarks in experiments.

Chiribella, Giulio

2013-01-01T23:59:59.000Z

479

Nonstandard optics from quantum spacetime  

E-Print Network (OSTI)

We study light propagation in the picture of semi-classical space-time that emerges in canonical quantum gravity in the loop representation. In such picture, where space-time exhibits a polymer-like structure at microscales, it is natural to expect departures from the perfect non-dispersiveness of ordinary vacuum. We evaluate these departures, computing the modifications to Maxwell's equations due to quantum gravity, and showing that under certain circumstances, non-vanishing corrections appear that depend on the helicity of propagating waves. These effects could lead to observable cosmological predictions of the discrete nature of quantum spacetime. In particular, recent observations of non-dispersiveness in the spectra of gamma-ray bursts at various energies could be used to constrain the type of semi-classical state that describes the universe.

Rodolfo Gambini; Jorge Pullin

1998-09-09T23:59:59.000Z

480

Improvements to the quantum evolutionary clustering  

Science Conference Proceedings (OSTI)

In previous work, a novel approach to data clustering based on quantum evolutionary algorithm has been proposed. In a comparison to other evolutionary clustering algorithms, the approach showed a high performance in terms of effectiveness and quality ...

Chafika Ramdane, Mohamed-Khireddine Kholladi

2013-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "quantum hall effect" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

www.mdpi.com/journal/ijms Cytotoxic Effects of CdSe Quantum Dots on Maturation of Mouse Oocytes, Fertilization, and Fetal Development  

E-Print Network (OSTI)

Abstract: Quantum dots (QDs) are useful novel luminescent markers, but their embryonic toxicity is yet to be fully established, particularly in oocyte maturation and sperm fertilization. Earlier experiments by our group show that CdSe-core QDs have cytotoxic effects on mouse blastocysts and are associated with defects in subsequent development. Here, we further investigate the influence of CdSe-core QDs on oocyte maturation, fertilization, and subsequent pre- and postimplantation development. CdSe-core QDs induced a significant reduction in the rates of oocyte maturation, fertilization, and in vitro embryo development, but not ZnS-coated CdSe QDs. Treatment of oocytes with 500 nM CdSe-core QDs during in vitro maturation (IVM) led to increased resorption of postimplantation embryos and decreased placental and fetal weights. To our knowledge, this is the first study to report the negative impact of CdSe-core QDs on mouse oocyte development. Moreover, surface modification of CdSe-core QDs with ZnS effectively prevented this cytotoxicity.

Ming-shu Hsieh; Nion-heng Shiao; Wen-hsiung Chan

2009-01-01T23:59:59.000Z

482

Modeling Quantum Information Systems abstract  

Science Conference Proceedings (OSTI)

Paul E. Black and Andrew W. Lane, Modeling Quantum Information Systems, Proc. SPIE, Vol. 5436, Quantum Information ...

2013-05-07T23:59:59.000Z

483

Quantum logic and coherent control  

Science Conference Proceedings (OSTI)

... CS Wood, "Quantum Computation, Spectroscopy of ... K. Fujikawa (Elsevier Science, Amsterdam, 1999 ... of trapped atomic ions," Advances in Quantum ...

2013-06-15T23:59:59.000Z

484

NIST Quantum Physics Division Staff  

Science Conference Proceedings (OSTI)

Quantum Physics Division. Staff. Name, Position, Phone. ... Physics Laboratory. Quantum Physics Division. Thomas O'Brian, Acting Chief. ...

2013-09-10T23:59:59.000Z