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Note: This page contains sample records for the topic "quantum numbers shown" from the National Library of EnergyBeta (NLEBeta).
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1

Quantum Random Number Generator  

Science Conference Proceedings (OSTI)

... trusted beacon of random numbers. You could conduct secure auctions, or certify randomized audits of data. One of the most ...

2013-08-30T23:59:59.000Z

2

Faster Quantum Number Factoring via Circuit Synthesis  

E-Print Network (OSTI)

A major obstacle to implementing Shor's quantum number-factoring algorithm is the large size of modular-exponentiation circuits. We reduce this bottleneck by customizing reversible circuits for modular multiplication to individual runs of Shor's algorithm. Our circuit-synthesis procedure exploits spectral properties of multiplication operators and constructs optimized circuits from the traces of the execution of an appropriate GCD algorithm. Empirically, gate counts are reduced by 4-5 times, and circuit latency is reduced by larger factors.

Igor L. Markov; Mehdi Saeedi

2013-01-15T23:59:59.000Z

3

Higgs Quantum Numbers in Weak Boson Fusion  

E-Print Network (OSTI)

Recently, the ATLAS and CMS experiments have reported the discovery of a Higgs like resonance at the LHC. The next analysis step will include the determination of its spin and CP quantum numbers or the form of its interaction Lagrangian channel-by-channel. We show how weak-boson-fusion Higgs production and associated ZH production can be used to separate different spin and CP states.

C. Englert; D. Goncalves-Netto; K. Mawatari; T. Plehn

2012-12-04T23:59:59.000Z

4

Quantum Phase Estimation with an Arbitrary Number of Qubits  

E-Print Network (OSTI)

Due to the great difficulty in scalability, quantum computers are limited in the number of qubits during the early stages of the quantum computing regime. In addition to the required qubits for storing the corresponding eigenvector, suppose we have additional k qubits available. Given such a constraint k, we propose an approach for the phase estimation for an eigenphase of exactly n-bit precision. This approach adopts the standard recursive circuit for quantum Fourier transform (QFT) and adopts classical bits to implement such a task. Our algorithm has the complexity of O(n \\log k), instead of O(n^2) in the conventional QFT, in terms of the total invocation of rotation gates. We also design a scheme to implement the factorization algorithm by using k available qubits via either the continued fractions approach or the simultaneous diophantine approximation.

Chen-Fu Chiang

2013-06-12T23:59:59.000Z

5

Waveguide photon-number-resolving detectors for quantum photonic integrated circuits  

E-Print Network (OSTI)

Quantum photonic integration circuits are a promising approach to scalable quantum processing with photons. Waveguide single-photon-detectors (WSPDs) based on superconducting nanowires have been recently shown to be compatible with single-photon sources for a monolithic integration. While standard WSPDs offer single-photon sensitivity, more complex superconducting nanowire structures can be configured to have photon-number-resolving capability. In this work, we present waveguide photon-number-resolving detectors (WPNRDs) on GaAs/Al0.75Ga0.25As ridge waveguides based on a series connection of nanowires. The detection of 0-4 photons has been demonstrated with a four-wire WPNRD, having a single electrical read-out. A device quantum efficiency ~24 % is reported at 1310 nm for the TE polarization.

Sahin, D; Zhou, Z; Jahanmirinejad, S; Mattioli, F; Leoni, R; Beetz, J; Lermer, M; Kamp, M; Höfling, S; Fiore, A

2013-01-01T23:59:59.000Z

6

Quantum receivers with squeezing and photon-number-resolving detectors  

E-Print Network (OSTI)

We propose quantum receivers with optical squeezing and photon-number-resolving detector (PNRD) for the near-optimal discrimination of quaternary phase-shift-keyed coherent state signals. The basic scheme is similar to the previous proposals (e.g. Phys. Rev. A 84, 042328 (2012)) in which displacement operations, on-off detectors, and electrical feedforward operations were used. Here we study two types of receivers where one installs optical squeezings and the other uses PNRDs instead of on-off detectors. We show that both receivers can attain lower error rates than that by the previous scheme and in particular, the PNRD based receiver has a significant gain under the fixed number of feedfoward steps. Moreover, we show that the PNRD based receiver can suppress the errors due to dark counts, which is not possible by the on-off detector based receiver with a limited number of feedforwards.

Shuro Izumi; Masahiro Takeoka; Kazuhiro Ema; Masahide Sasaki

2013-02-12T23:59:59.000Z

7

Discriminating quantum-optical beam-splitter channels with number-diagonal signal states: Applications to quantum reading and target detection  

Science Conference Proceedings (OSTI)

We consider the problem of distinguishing, with minimum probability of error, two optical beam-splitter channels with unequal complex-valued reflectivities using general quantum probe states entangled over M signal and M' idler mode pairs of which the signal modes are bounced off the beam splitter while the idler modes are retained losslessly. We obtain a lower bound on the output state fidelity valid for any pure input state. We define number-diagonal signal (NDS) states to be input states whose density operator in the signal modes is diagonal in the multimode number basis. For such input states, we derive series formulas for the optimal error probability, the output state fidelity, and the Chernoff-type upper bounds on the error probability. For the special cases of quantum reading of a classical digital memory and target detection (for which the reflectivities are real valued), we show that for a given input signal photon probability distribution, the fidelity is minimized by the NDS states with that distribution and that for a given average total signal energy N{sub s}, the fidelity is minimized by any multimode Fock state with N{sub s} total signal photons. For reading of an ideal memory, it is shown that Fock state inputs minimize the Chernoff bound. For target detection under high-loss conditions, a no-go result showing the lack of appreciable quantum advantage over coherent state transmitters is derived. A comparison of the error probability performance for quantum reading of number state and two-mode squeezed vacuum state (or EPR state) transmitters relative to coherent state transmitters is presented for various values of the reflectances. While the nonclassical states in general perform better than the coherent state, the quantitative performance gains differ depending on the values of the reflectances. The experimental outlook for realizing nonclassical gains from number state transmitters with current technology at moderate to high values of the reflectances is argued to be good.

Nair, Ranjith [Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2011-09-15T23:59:59.000Z

8

Exact c-number Representation of Non-Markovian Quantum Dissipation  

E-Print Network (OSTI)

The reduced dynamics of a quantum system interacting with a linear heat bath finds an exact representation in terms of a stochastic Schr{\\"o}dinger equation. All memory effects of the reservoir are transformed into noise correlations and mean-field friction. The classical limit of the resulting stochastic dynamics is shown to be a generalized Langevin equation, and conventional quantum state diffusion is recovered in the Born--Markov approximation. The non-Markovian exact dynamics, valid at arbitrary temperature and damping strength, is exemplified by an application to the dissipative two-state system.

J. Stockburger; H. Grabert

2002-03-08T23:59:59.000Z

9

Quantum mechanics of layers with a finite number of point perturbations  

Science Conference Proceedings (OSTI)

We study spectral and scatteringproperties of a spinless quantum particle confined to an infinite planar layer with hard walls containing a finite number of point perturbations. A solvable character of the model follows from the explicit form of the Hamiltonian resolvent obtained by means of Krein’s formula. We prove the existence of bound states

P. Exner; K. N?mcová

2002-01-01T23:59:59.000Z

10

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

11

Manipulating atoms in an optical lattice: Fractional fermion number and its optical quantum measurement  

E-Print Network (OSTI)

We provide a detailed analysis of our previously proposed scheme [Phys. Rev. Lett. 88, 180401, (2002)] to engineer the profile of the hopping amplitudes for atomic gases in a 1D optical lattice so that the particle number becomes fractional. We consider a constructed system of a dilute two-species gas of fermionic atoms where the two components are coupled via a coherent electromagnetic field with a topologically nontrivial phase profile. We show both analytically and numerically how the resulting atomic Hamiltonian in a prepared dimerized optical lattice with a defect in the pattern of alternating hopping amplitudes exhibits a fractional fermion number. In particular, in the low-energy limit we demonstrate the equivalence of the atomic Hamiltonian to a relativistic Dirac Hamiltonian describing fractionalization in quantum field theory. Expanding on our earlier argument [Phys. Rev. Lett. 91, 150404 (2003)] we show how the fractional eigenvalues of the particle number operator can be detected via light scattering. In particular, we show how scattering of far-off resonant light can convey information about the counting statistics of the atoms in an optical lattice, including state-selective atom density profiles and atom number fluctuations. Optical detection could provide a truly quantum mechanical measurement of the particle number fractionalization in a dilute atomic gas.

J. Ruostekoski; J. Javanainen; G. V. Dunne

2007-09-13T23:59:59.000Z

12

Evolution of the deformation state and composition as a result of changes in the number of quantum wells in multilayered InGaN/GaN structures  

Science Conference Proceedings (OSTI)

The methods of high-resolution X-ray diffraction have been used to study the multilayered structures in an In{sub x}Ga{sub 1-x}N/GaN system grown by the method of metal-organic chemical-vapor deposition. A correlation between the strain state (relaxation) of the system, the indium content within quantum wells, the ratio of the barrier/well thicknesses, and the number of quantum wells in the active superlattice is established. It is shown that partial relaxation is observed even in a structure with one quantum well. The results we obtained indicate that the relaxation processes are bound to appreciably affect the optical characteristics of devices.

Kladko, V. P., E-mail: kladko@isp.kiev.ua; Kuchuk, A. V.; Safriuk, N. V.; Machulin, V. F.; Belyaev, A. E.; Konakova, R. V. [National Academy of Sciences of Ukraine, Lashkaryov Institute of Semiconductor Physics (Ukraine); Yavich, B. S. [ZAO Svetlana-Optoelectronics (Russian Federation); Ber, B. Ya.; Kazantsev, D. Yu. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation)

2011-06-15T23:59:59.000Z

13

Efficient Method for Quantum Number Projection and Its Application to Tetrahedral Nuclear States  

E-Print Network (OSTI)

We have developed an efficient method for quantum number projection from most general HFB type mean-field states, where all the symmetries like axial symmetry, number conservation, parity and time-reversal invariance are broken. Applying the method, we have microscopically calculated, for the first time, the energy spectra based on the exotic tetrahedral deformation in $^{108,110}$Zr. The nice low-lying rotational spectra, which have all characteristic features of the molecular tetrahedral rotor, are obtained for large tetrahedral deformation, $\\alpha_{32} \\gtsim 0.25$, while the spectra are of transitional nature between vibrational and rotational with rather high excitation energies for $\\alpha_{32}\\approx 0.1-0.2$

S. Tagami; Y. R. Shimizu; J. Dudek

2013-01-15T23:59:59.000Z

14

Contribution from the interaction Hamiltonian to the expectation value of particle number with the non-equilibrium quantum field theory  

SciTech Connect

We develop the method analyzing particle number non-conserving phenomena with non-equilibrium quantum field-theory. In this study, we consider a CP violating model with interaction Hamiltonian that breaks particle number conservation. To derive the quantum Boltzmann equation for the particle number, we solve Schwinger-Dyson equation, which are obtained from two particle irreducible closed-time-path (2PI CTP) effective action. In this calculation, we show the contribution from interaction Hamiltonian to the time evolution of expectation value of particle number.

Hotta, Ryuuichi; Morozumi, Takuya; Takata, Hiroyuki [Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526 (Japan); Tomsk state Pedagogical University Tomsk 634041 (Russian Federation)

2012-07-27T23:59:59.000Z

15

Number  

Office of Legacy Management (LM)

' ' , /v-i 2 -i 3 -A, This dow'at consists ~f--~-_,_~~~p.~,::, Number -------of.-&--copies, 1 Series.,-a-,-. ! 1 THE UNIVERSITY OF ROCHESTER 1; r-.' L INTRAMURALCORRESPONDENCE i"ks' 3 2.. September 25, 1947 Memo.tor Dr. A. H, Dovdy . From: Dr. H. E, Stokinger Be: Trip Report - Mayvood Chemical Works A trip vas made Nednesday, August 24th vith Messrs. Robert W ilson and George Sprague to the Mayvood Chemical F!orks, Mayvood, New Jersey one of 2 plants in the U.S.A. engaged in the production of thorium compounds. The purpose of the trip vas to: l 1. Learn the type of chemical processes employed in the thorium industry (thorium nitrate). 2. Survey conditions of eeosure of personnel associated vith these chemical processes. 3. Obtain samples of atmospheric contaminants in the plant, as

16

Photon-Number-Splitting-attack resistant Quantum Key Distribution Protocols without sifting  

E-Print Network (OSTI)

We propose a family of sifting-less quantum-key-distribution protocols which use reverse-reconciliation, and are based on weak coherent pulses (WCPs) polarized along m different directions. When m=4, the physical part of the protocol is identical to most experimental implementations of BB84 and SARG04 protocols and they differ only in classical communications and data processing. We compute their total keyrate as function of the channel transmission T, using general information theoretical arguments and we show that they have a higher keyrate than the more standard protocols, both for fixed and optimized average photon number of the WCPs. When no decoy-state protocols (DSPs) are applied, the scaling of the keyrate with transmission is improved from T2 for BB84 to T^(1+1/(m-2)). If a DSP is applied, we show how the keyrates scale linearly with T, with an improvement of the prefactor by 75.96 % for m=4. High values of $ m $ allow to asymptotically approach the keyrate obtained with ideal single photon pulses. The fact that the keyrates of these sifting-less protocols are higher compared to those of the aforementioned more standard protocols show that the latter are not optimal, since they do not extract all the available secret key from the experimental correlations.

Fabio Grazioso; Frédéric Grosshans

2013-06-25T23:59:59.000Z

17

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

18

How are lighting exemptions and allowances shown in COMcheck...  

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

Guides eLearning Model Policies Glossary Related Links ACE Learning Series How are lighting exemptions and allowances shown in COMcheck? Exemptions and allowances for lighting...

19

Quantum convolutional stabilizer codes  

E-Print Network (OSTI)

Quantum error correction codes were introduced as a means to protect quantum information from decoherance and operational errors. Based on their approach to error control, error correcting codes can be divided into two different classes: block codes and convolutional codes. There has been significant development towards finding quantum block codes, since they were first discovered in 1995. In contrast, quantum convolutional codes remained mainly uninvestigated. In this thesis, we develop the stabilizer formalism for quantum convolutional codes. We define distance properties of these codes and give a general method for constructing encoding circuits, given a set of generators of the stabilizer of a quantum convolutional stabilizer code, is shown. The resulting encoding circuit enables online encoding of the qubits, i.e., the encoder does not have to wait for the input transmission to end before starting the encoding process. We develop the quantum analogue of the Viterbi algorithm. The quantum Viterbi algorithm (QVA) is a maximum likehood error estimation algorithm, the complexity of which grows linearly with the number of encoded qubits. A variation of the quantum Viterbi algorithm, the Windowed QVA, is also discussed. Using Windowed QVA, we can estimate the most likely error without waiting for the entire received sequence.

Chinthamani, Neelima

2005-05-01T23:59:59.000Z

20

Finite groups and quantum physics  

Science Conference Proceedings (OSTI)

Concepts of quantum theory are considered from the constructive 'finite' point of view. The introduction of a continuum or other actual infinities in physics destroys constructiveness without any need for them in describing empirical observations. It is shown that quantum behavior is a natural consequence of symmetries of dynamical systems. The underlying reason is that it is impossible in principle to trace the identity of indistinguishable objects in their evolution-only information about invariant statements and values concerning such objects is available. General mathematical arguments indicate that any quantum dynamics is reducible to a sequence of permutations. Quantum phenomena, such as interference, arise in invariant subspaces of permutation representations of the symmetry group of a dynamical system. Observable quantities can be expressed in terms of permutation invariants. It is shown that nonconstructive number systems, such as complex numbers, are not needed for describing quantum phenomena. It is sufficient to employ cyclotomic numbers-a minimal extension of natural numbers that is appropriate for quantum mechanics. The use of finite groups in physics, which underlies the present approach, has an additional motivation. Numerous experiments and observations in the particle physics suggest the importance of finite groups of relatively small orders in some fundamental processes. The origin of these groups is unclear within the currently accepted theories-in particular, within the Standard Model.

Kornyak, V. V., E-mail: kornyak@jinr.ru [Joint Institute for Nuclear Physics, Laboratory of Information Tecnnologies (Russian Federation)

2013-02-15T23:59:59.000Z

Note: This page contains sample records for the topic "quantum numbers shown" 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

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

22

Universal quantum computation with shutter logic  

Science Conference Proceedings (OSTI)

We show that universal quantum logic can be achieved using only linear optics and a quantum shutter device. With these elements, we design a quantum memory for any number of qubits and a CNOT gate which are the basis of a universal quantum computer. ... Keywords: interaction-free measurement, optical CNOT gate, optical quantum computation, quantum interrogation, quantum memory, quantum shutter, universal quantum computer

Juan Carlos García-Escartín; Pedro Chamorro-Posada

2006-09-01T23:59:59.000Z

23

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

24

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

25

Thin Film Solar Cells Derived from Sintered Semiconductor Quantum Dots: Cooperative Research and Development Final Report, CRADA number CRD-07-00226  

Science Conference Proceedings (OSTI)

The NREL/Evident team will develop techniques to fabricate thin film solar cells where the absorption layers comprising the solar cells are derived from sintered semiconductor quantum dots.

Ginley, D. S.

2010-07-01T23:59:59.000Z

26

Quantum walks: a comprehensive review  

E-Print Network (OSTI)

Quantum walks, the quantum mechanical counterpart of classical random walks, is an advanced tool for building quantum algorithms that has been recently shown to constitute a universal model of quantum computation. Quantum walks is now a solid field of research of quantum computation full of exciting open problems for physicists, computer scientists, mathematicians and engineers. In this paper we review theoretical advances on the foundations of both discrete- and continuous-time quantum walks, together with the role that randomness plays in quantum walks, the connections between the mathematical models of coined discrete quantum walks and continuous quantum walks, the quantumness of quantum walks, a summary of papers published on discrete quantum walks and entanglement as well as a succinct review of experimental proposals and realizations of discrete-time quantum walks. Furthermore, we have reviewed several algorithms based on both discrete- and continuous-time quantum walks as well as a most important resul...

Venegas-Andraca, Salvador E

2012-01-01T23:59:59.000Z

27

Critical error rate of quantum-key-distribution protocols versus the size and dimensionality of the quantum alphabet  

SciTech Connect

A quantum-information analysis of how the size and dimensionality of the quantum alphabet affect the critical error rate of the quantum-key-distribution (QKD) protocols is given on an example of two QKD protocols--the six-state and {infinity}-state (i.e., a protocol with continuous alphabet) ones. In the case of a two-dimensional Hilbert space, it is shown that, under certain assumptions, increasing the number of letters in the quantum alphabet up to infinity slightly increases the critical error rate. Increasing additionally the dimensionality of the Hilbert space leads to a further increase in the critical error rate.

Sych, Denis V.; Grishanin, Boris A.; Zadkov, Victor N. [International Laser Center and Faculty of Physics, M.V. Lomonosov Moscow State University, 119899 Moscow (Russian Federation)

2004-11-01T23:59:59.000Z

28

Cavity Quantum Electrodynamics (CQED)-Based Quantum LDPC  

E-Print Network (OSTI)

Cavity Quantum Electrodynamics (CQED)-Based Quantum LDPC Encoders and Decoders Volume 3, Number 4-0655/$26.00 ©2011 IEEE #12;Cavity Quantum Electrodynamics (CQED)-Based Quantum LDPC Encoders and Decoders Ivan B: Quantum information processing (QIP) relies on delicate superposition states that are sensitive

Djordjevic, Ivan B.

29

Parabolic Quantum Cloak.  

E-Print Network (OSTI)

??It is shown that the parabolic quantum cloak can be theoretically design by using âtransformation design methodâ. We discuss the possibility to build a parabolic… (more)

Chang, Yu-Hsuan

2013-01-01T23:59:59.000Z

30

Quantum Graphical Models and Belief Propagation  

E-Print Network (OSTI)

Belief Propagation algorithms acting on Graphical Models of classical probability distributions, such as Markov Networks, Factor Graphs and Bayesian Networks, are amongst the most powerful known methods for deriving probabilistic inferences amongst large numbers of random variables. This paper presents a generalization of these concepts and methods to the quantum case, based on the idea that quantum theory can be thought of as a noncommutative, operator-valued, generalization of classical probability theory. Some novel characterizations of quantum conditional independence are derived, and definitions of Quantum n-Bifactor Networks, Markov Networks, Factor Graphs and Bayesian Networks are proposed. The structure of Quantum Markov Networks is investigated and some partial characterization results are obtained, along the lines of the Hammersely-Clifford theorem. A Quantum Belief Propagation algorithm is presented and is shown to converge on 1-Bifactor Networks and Markov Networks when the underlying graph is a tree. The use of Quantum Belief Propagation as a heuristic algorithm in cases where it is not known to converge is discussed. Applications to decoding quantum error correcting codes and to the simulation of many-body quantum systems are described.

Matthew Leifer; David Poulin

2007-08-09T23:59:59.000Z

31

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.

32

Distillability and positivity of partial transposes in general quantum field systems  

E-Print Network (OSTI)

Criteria for distillability, and the property of having a positive partial transpose, are introduced for states of general bipartite quantum systems. The framework is sufficiently general to include systems with an infinite number of degrees of freedom, including quantum fields. We show that a large number of states in relativistic quantum field theory, including the vacuum state and thermal equilibrium states, are distillable over subsystems separated by arbitrary spacelike distances. These results apply to any quantum field model. It will also be shown that these results can be generalized to quantum fields in curved spacetime, leading to the conclusion that there is a large number of quantum field states which are distillable over subsystems separated by an event horizon.

Rainer Verch; Reinhard F. Werner

2004-03-11T23:59:59.000Z

33

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

34

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

35

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

36

Atom optics kicked rotor: experimental evidence for a pendulum description of the quantum resonance  

E-Print Network (OSTI)

We present measurements of the mean energy for an atom optics kicked rotor ensemble close to quantum resonance. Oscillations in the mean energy in this regime are are shown to be in agreement with a quasi--classical pendulum approximation. The period of the oscillations is shown to scale with a single variable, which depends on the number of kicks.

S. Wayper; M. Sadgrove; W. Simpson; M. D. Hoogerland

2005-04-29T23:59:59.000Z

37

New Journal of Physics Publishes Quantum Papers  

Science Conference Proceedings (OSTI)

... NIST Quantum Cryptography Highlighted in New Journal of Physics. Recent research has shown that the security of a key ...

2010-10-05T23:59:59.000Z

38

Controlled gates for multi-level quantum computation  

Science Conference Proceedings (OSTI)

Multi-level (ML) quantum logic can potentially reduce the number of inputs/outputs or quantum cells in a quantum circuit which is a limitation in current quantum technology. In this paper we propose theorems about ML-quantum and reversible logic circuits. ... Keywords: Controlled gate, Multi-level logic gates, Quantum computing, Quantum cost, Reversible logic

Majid Mohammadi; Aliakbar Niknafs; Mohammad Eshghi

2011-04-01T23:59:59.000Z

39

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

40

Photovoltaic Cell Quantum Efficiency | Department of Energy  

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

Quantum Efficiency Photovoltaic Cell Quantum Efficiency August 20, 2013 - 3:05pm Addthis Quantum efficiency (QE) is the ratio of the number of charge carriers collected by a...

Note: This page contains sample records for the topic "quantum numbers shown" 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

Photovoltaic Cell Quantum Efficiency  

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

Quantum efficiency (QE) is the ratio of the number of charge carriers collected by a photovoltaic (PV) cell to the number of photons—or packets of light—of a given energy shining on the solar cell....

42

Transverse electric conductivity in quantum collisional plasma in Mermin approach  

E-Print Network (OSTI)

Formulas for transversal electric conductivity and dielectric permeability of quantum collisional plasma are deduced. The kinetic equation for a density matrix in relaxation approaching in momentum space is used. It is shown, that when Planck's constant tends to zero, these deduced formulas pass in classical expressions and when frequency of electron collision tends to zero (i.e. plasma passes in collisionless plasma), the deduced formulas pass in deduced earlier by Lindhard. It is shown also, that when the wave number tends to zero, quantum conductivity passes in the classical one. Graphic comparison of the deduced conductivity with Lindhard's conductivity and with classical conductivity is carry out.

A. V. Latyshev; A. A. Yushkanov

2011-09-29T23:59:59.000Z

43

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

44

Quantum Democracy Is Possible  

E-Print Network (OSTI)

It is shown that, since an ultrafilter over an operator-algebraically finite (i.e. isomorphic to the lattice of projectors of a finite Von Neumann algebra) quantum logic is not necessarily principal, Arrow's Impossibility Theorem doesn't extend to the quantum case.

Gavriel Segre

2008-06-23T23:59:59.000Z

45

Fractals and quantum mechanics  

Science Conference Proceedings (OSTI)

A new application of a fractal concept to quantum physics has been developed. The fractional path integrals over the paths of the Lévy flights are defined. It is shown that if fractality of the Brownian trajectories leads to standard quantum mechanics

Nick Laskin

2000-01-01T23:59:59.000Z

46

Secure quantum string seal exists  

E-Print Network (OSTI)

It was claimed that all quantum string seals are insecure [H. F. Chau, quant-ph/0602099]. However, here it will be shown that for imperfect quantum string seals, the information obtained by the measurement proposed in that reference is trivial. Therefore imperfect quantum string seals can be unconditionally secure.

Guang Ping He

2006-02-18T23:59:59.000Z

47

Final Rulemaking, 10 CFR Part 1021, with Amendments Shown In Tracked Changes  

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

This document presents the final rule as issued September 27, 2011, amendments shown with changes tracked (additions in blue, deletions in red). Categorical exclusions are listed in Appendices A...

48

Subthermocline Eddies in the Western Equatorial Pacific as Shown by an Eddy-Resolving OGCM  

Science Conference Proceedings (OSTI)

Sporadic in situ observations have shown evidence that subthermocline eddies exist off the Mindanao coast. These subthermocline eddies are believed to play an important role in the heat, freshwater, and other ocean property transports of the ...

Tzu-Ling Chiang; Tangdong Qu

2013-07-01T23:59:59.000Z

49

Energy flows are shown in energy units as well as dollar values...  

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

flows are shown in energy units as well as dollar values. Financial and technical management can now communicate by looking at data that is meaningful to both- One of the...

50

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 ...

51

DOE Takes Action to Stop the Sales of Air-Con Air Conditioner Models Shown  

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

Takes Action to Stop the Sales of Air-Con Air Conditioner Takes Action to Stop the Sales of Air-Con Air Conditioner Models Shown to Violate Federal Energy Efficiency Appliance Standards DOE Takes Action to Stop the Sales of Air-Con Air Conditioner Models Shown to Violate Federal Energy Efficiency Appliance Standards September 23, 2010 - 12:00am Addthis Washington, DC - The Department of Energy announced today that it has taken action against Air-Con, International, requiring the company to stop selling certain air conditioning systems in the U.S. that have been shown to violate minimum energy efficiency appliance standards. DOE is proposing a civil penalty of more than $230,000 for importing and distributing these inefficient cooling products. This action and the proposed penalties are part of the Department's continued commitment to act aggressively to remove

52

Several studies have shown that the availability of solar power plants often is  

E-Print Network (OSTI)

Several studies have shown that the availability of solar power plants often is high during times conditioning. These peaks are intensi- fied during heat waves, which are fueled by solar gain. Thus the equivalent of peaking capaci- ty via load curtailment and user-sited power generation. When dispersed PV

Perez, Richard R.

53

Modified gravity from the quantum part of the metric  

E-Print Network (OSTI)

It is shown that if a metric in quantum gravity can be decomposed as a sum of classical and quantum parts then Einstein quantum gravity looks approximately like modified gravity with a nonminimal interaction between gravity and matter.

Vladimir Dzhunushaliev; Vladimir Folomeev; Burkhard Kleihaus; Jutta Kunz

2013-12-01T23:59:59.000Z

54

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

55

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

56

All inorganic colloidal quantum dot LEDs  

E-Print Network (OSTI)

This thesis presents the first colloidal quantum dot light emitting devices (QD-LEDs) with metal oxide charge transport layers. Colloidally synthesized quantum dots (QDs) have shown promise as the active material in ...

Wood, Vanessa Claire

2007-01-01T23:59:59.000Z

57

Quantum computers: Definition and implementations  

Science Conference Proceedings (OSTI)

The DiVincenzo criteria for implementing a quantum computer have been seminal in focusing both experimental and theoretical research in quantum-information processing. These criteria were formulated specifically for the circuit model of quantum computing. However, several new models for quantum computing (paradigms) have been proposed that do not seem to fit the criteria well. Therefore, the question is what are the general criteria for implementing quantum computers. To this end, a formal operational definition of a quantum computer is introduced. It is then shown that, according to this definition, a device is a quantum computer if it obeys the following criteria: Any quantum computer must consist of a quantum memory, with an additional structure that (1) facilitates a controlled quantum evolution of the quantum memory; (2) includes a method for information theoretic cooling of the memory; and (3) provides a readout mechanism for subsets of the quantum memory. The criteria are met when the device is scalable and operates fault tolerantly. We discuss various existing quantum computing paradigms and how they fit within this framework. Finally, we present a decision tree for selecting an avenue toward building a quantum computer. This is intended to help experimentalists determine the most natural paradigm given a particular physical implementation.

Perez-Delgado, Carlos A.; Kok, Pieter [Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield, S3 7RH (United Kingdom)

2011-01-15T23:59:59.000Z

58

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

59

Is quantum mechanics exact?  

SciTech Connect

We formulate physically motivated axioms for a physical theory which for systems with a finite number of degrees of freedom uniquely lead to quantum mechanics as the only nontrivial consistent theory. Complex numbers and the existence of the Planck constant common to all systems arise naturally in this approach. The axioms are divided into two groups covering kinematics and basic measurement theory, respectively. We show that even if the second group of axioms is dropped, there are no deformations of quantum mechanics which preserve the kinematic axioms. Thus, any theory going beyond quantum mechanics must represent a radical departure from the usual a priori assumptions about the laws of nature.

Kapustin, Anton [California Institute of Technology, Pasadena, California 91125 (United States)] [California Institute of Technology, Pasadena, California 91125 (United States)

2013-06-15T23:59:59.000Z

60

A short remark on negative energy densities and quantum inequalities  

E-Print Network (OSTI)

In quantum field theory it is generally known that the energy density may be negative at a given point in spacetime. A number of papers have shown that there is a restriction on this energy density which is called a quantum inequality (QI). A QI is the lower bound to the "weighted average" of the energy density at a given point integrated over a time dependent sampling function. In this paper we give an example of a sampling function for which there is no QI.

Solomon, Dan

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "quantum numbers shown" 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

A short remark on negative energy densities and quantum inequalities  

E-Print Network (OSTI)

In quantum field theory it is generally known that the energy density may be negative at a given point in spacetime. A number of papers have shown that there is a restriction on this energy density which is called a quantum inequality (QI). A QI is the lower bound to the "weighted average" of the energy density at a given point integrated over a time dependent sampling function. In this paper we give an example of a sampling function for which there is no QI.

Dan Solomon

2009-01-05T23:59:59.000Z

62

On Quantum Integrable Systems  

SciTech Connect

Many quantum integrable systems are obtained using an accelerator physics technique known as Ermakov (or normalized variables) transformation. This technique was used to create classical nonlinear integrable lattices for accelerators and nonlinear integrable plasma traps. Now, all classical results are carried over to a nonrelativistic quantum case. In this paper we have described an extension of the Ermakov-like transformation to the Schroedinger and Pauli equations. It is shown that these newly found transformations create a vast variety of time dependent quantum equations that can be solved in analytic functions, or, at least, can be reduced to time-independent ones.

Danilov, Viatcheslav; /Oak Ridge; Nagaitsev, Sergei; /Fermilab

2011-11-01T23:59:59.000Z

63

JOB NUMBER  

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

. . . . . . . . . .: LEAVE BLANK (NARA use only) JOB NUMBER N/-&*W- 9d - 3 DATE RECEIVED " -1s - 9 J - NOTIFICATION TOAGENCY , In accordance with the provisions of 44 U.S.C. 3303a the disposition request. including amendments, is ap roved except , . l for items that may be marke,, ,"dis osition not approved" or "withdrawn in c o i m n 10. 4. NAME OF PERSON WITH WHOM TO CONFER 5 TELEPHONE Jannie Kindred (202) 5&-333 5 - 2 -96 6 AGENCYCERTIFICATION -. ~ - I hereby certify that I am authorized to act for this agency in matters pertaining to the disposition of its records and that the records roposed for disposal are not now needed for the business of this agency or wiRnot be needed after t G t r & s s d ; and that written concurrence from

64

Case Number:  

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

Name of Petitioner: Name of Petitioner: Date of Filing: Case Number: Department of Energy Washington, DC 20585 JUL 2 2 2009 DEPARTMENT OF ENERGY OFFICE OF HEARINGS AND APPEALS Appeal Dean P. Dennis March 2, 2009 TBA-0072 Dean D. Dennis filed a complaint of retaliation under the Department of Energy (DOE) Contractor Employee Protection Program, 10 C.F.R. Part 708. Mr. Dennis alleged that he engaged in protected activity and that his employer, National Security Technologies, LLC (NSTec ), subsequently terminated him. An Office of Hearings and Appeals (OHA) Hearing Officer denied relief in Dean P. Dennis, Case No. TBH-0072, 1 and Mr. Dennis filed the instant appeal. As discussed below, the appeal is denied. I. Background The DOE established its Contractor Employee Protection Program to "safeguard public

65

KPA Number  

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

Supports CMM-SW Level 3 Supports CMM-SW Level 3 Mapping of the DOE Information Systems Engineering Methodology to the Software Engineering Institute (SEI) Software Capability Maturity Model (CMM-SW) level 3. Date: September 2002 Page 1 KPA Number KPA Activity SEM Section SEM Work Product SQSE Web site http://cio.doe.gov/sqse ORGANIZATION PROCESS FOCUS OPF-1 The software process is assessed periodically, and action plans are developed to address the assessment findings. Chapter 1 * Organizational Process Management * Process Improvement Action Plan * Methodologies ! DOE Methodologies ! SEM OPF-2 The organization develops and maintains a plan for its software process development and improvement activities. Chapter 1 * Organizational Process Management * Process Improvement

66

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

67

Graph Homomorphisms for Quantum Players  

E-Print Network (OSTI)

A homomorphism from a graph X to a graph Y is an adjacency preserving mapping f:V(X)->V(Y). We consider a nonlocal game in which Alice and Bob are trying to convince a verifier with certainty that a graph X admits a homomorphism to Y. This is a generalization of the well-studied graph coloring game. Via systematic study of quantum homomorphisms we prove new results for graph coloring. Most importantly, we show that the Lovasz theta number of the complement lower bounds the quantum chromatic number, which itself is not known to be computable. We also show that other quantum graph parameters, such as quantum independence number, can differ from their classical counterparts. Finally, we show that quantum homomorphisms closely relate to zero-error channel capacity. In particular, we use quantum homomorphisms to construct graphs for which entanglement-assistance increases their one-shot zero-error capacity.

David E. Roberson; Laura Mancinska

2012-12-07T23:59:59.000Z

68

Transverse electric conductivity and dielectric function in quantum non-degenerate collisional plasma by Mermin approach  

E-Print Network (OSTI)

Formulas for transverse conductance in quantum non-degenerate collisional plasma are deduced. The kinetic equation in momentum space in the relaxation approach is used. It is shown, that at $\\hbar\\to 0$ the derived formula transfers to the classical one. It is shown also, that when values of dimensionless wave numbers are small, the conductance formula transfers in the known formula for classical non-degenerate plasmas.

A. V. Latyshev; A. A. Yushkanov

2012-06-18T23:59:59.000Z

69

Transverse electric conductivity and dielectric function in quantum Maxwellian collisional plasma by Mermin approach  

E-Print Network (OSTI)

Formulas for transverse conductance in quantum Maxwellian collisional plasma are deduced. The kinetic Von Neumann equation in momentum space with collision integral in the relaxation form is used. It is shown, that at Planck's constant tends to zero the derived formula transfers to the classical one. It is shown also, that when values of dimensionless wave numbers are small, the conductance formula transfers in the known formula for classical Maxwellian plasmas.

Latyshev, A V

2012-01-01T23:59:59.000Z

70

Transverse electric conductivity and dielectric function in quantum Maxwellian collisional plasma by Mermin approach  

E-Print Network (OSTI)

Formulas for transverse conductance in quantum Maxwellian collisional plasma are deduced. The kinetic Von Neumann equation in momentum space with collision integral in the relaxation form is used. It is shown, that at Planck's constant tends to zero the derived formula transfers to the classical one. It is shown also, that when values of dimensionless wave numbers are small, the conductance formula transfers in the known formula for classical Maxwellian plasmas.

A. V. Latyshev; A. A. Yushkanov

2012-06-26T23:59:59.000Z

71

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

72

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

73

Bohmian mechanics contradicts quantum mechanics  

E-Print Network (OSTI)

Bohmian mechanics contradicts quantum mechanics Arnold Neumaier Institut fur Mathematik, Universit://solon.cma.univie.ac.at/#24;neum/ Abstract. It is shown that, for a harmonic oscillator in the ground state, Bohmian mechanics and quantum mechanics predict values of opposite sign for certain time correlations. The discrepancy can

Neumaier, Arnold

74

Quantum Gravitational Uncertainty of Transverse Position  

E-Print Network (OSTI)

It is argued that holographic bounds on the information content of spacetime might be directly measurable. A new uncertainty principle is conjectured to arise from quantum indeterminacy of nearly flat spacetime: Angular orientations of null trajectories of spatial length L are uncertain, with standard deviation in each transverse direction \\Delta \\theta> \\sqrt{l_P/L}, where l_p denotes the Planck length. It is shown that this angular uncertainty corresponds to the information loss and nonlocality that occur if 3+1-D spacetime has a holographic dual description in terms of Planck-scale waves on a 2+1D screen with encoding close to the Planck diffraction limit, and agrees with covariant holographic entropy bounds on total number of degrees of freedom. The spectrum and spatial structure of predicted quantum-gravitational ``holographic noise'' are estimated to be directly measurable over a broad range of frequencies using interferometers with current technology.

Craig J. Hogan

2007-03-29T23:59:59.000Z

75

Languages recognized by nondeterministic quantum finite automata  

Science Conference Proceedings (OSTI)

The nondeterministic quantum finite automaton (NQFA) is the only known case wherea one-way quantum finite automaton (QFA) model has been shown to be strictly superiorin terms of language recognition power to its probabilistic counterpart. We give acharacterization ... Keywords: nondeterministic quantum finite automata, one-sided unbounded error, probabilistic automata, sublogarithmic space complexity, two-sided unbounded error

Abuzer Yakaryilmaz; A. C. Cem Say

2010-09-01T23:59:59.000Z

76

General model of quantum key distribution  

E-Print Network (OSTI)

A general mathematical framework for quantum key distribution based on the concepts of quantum channel and Turing machine is suggested. The security for its special case is proved. The assumption is that the adversary can perform only individual (in essence, classical) attacks. For this case an advantage of quantum key distribution over classical one is shown.

A. S. Trushechkin; I. V. Volovich

2005-04-20T23:59:59.000Z

77

Hyper-Hamiltonian quantum mechanics  

E-Print Network (OSTI)

We present a modification of quantum mechanics with a *possible worlds* semantics. It is shown that `gauge' degrees of freedom along possible worlds can be used to encode gravitational information.

Vladimir Trifonov

2006-03-02T23:59:59.000Z

78

Quantum computation and hidden variables  

E-Print Network (OSTI)

Many physicists limit oneself to an instrumentalist description of quantum phenomena and ignore the problems of foundation and interpretation of quantum mechanics. This instrumentalist approach results to "specialization barbarism" and mass delusion concerning the problem, how a quantum computer can be made. The idea of quantum computation can be described within the limits of quantum formalism. But in order to understand how this idea can be put into practice one should realize the question: "What could the quantum formalism describe?", in spite of the absence of an universally recognized answer. Only a realization of this question and the undecided problem of quantum foundations allows to see in which quantum systems the superposition and EPR correlation could be expected. Because of the "specialization barbarism" many authors are sure that Bell proved full impossibility of any hidden-variables interpretation. Therefore it is important to emphasize that in reality Bell has restricted to validity limits of the no- hidden-variables proof and has shown that two-state quantum system can be described by hidden variables. The later means that no experimental result obtained on two-state quantum system can prove the existence of superposition and violation of the realism. One should not assume before unambiguous experimental evidence that any two-state quantum system is quantum bit. No experimental evidence of superposition of macroscopically distinct quantum states and of a quantum bit on base of superconductor structure was obtained for the present. Moreover same experimental results can not be described in the limits of the quantum formalism.

V. V. Aristov; A. V. Nikulov

2010-07-12T23:59:59.000Z

79

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

80

Can quantum chemistry be performed on a small quantum computer?  

E-Print Network (OSTI)

As quantum computing technology improves and quantum computers with a small but non-trivial number of N > 100 qubits appear feasible in the near future the question of possible applications of small quantum computers gains importance. One frequently mentioned application is Feynman's original proposal of simulating quantum systems, and in particular the electronic structure of molecules and materials. In this paper, we analyze the computational requirements for one of the standard algorithms to perform quantum chemistry on a quantum computer. We focus on the quantum resources required to find the ground state of a molecule twice as large as what current classical computers can solve exactly. We find that while such a problem requires about a ten-fold increase in the number of qubits over current technology, the required increase in the number of gates that can be coherently executed is many orders of magnitude larger. This suggests that for quantum computation to become useful for quantum chemistry problems, drastic algorithmic improvements will be needed.

Dave Wecker; Bela Bauer; Bryan K. Clark; Matthew B. Hastings; Matthias Troyer

2013-12-05T23:59:59.000Z

Note: This page contains sample records for the topic "quantum numbers shown" 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 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

82

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

83

Classical and quantum description of electron trapping during the Cherenkov beam instability in plasma  

SciTech Connect

A nonlinear quantum theory of the Cherenkov instability of a nonrelativistic monoenergetic electron beam in a cold plasma is constructed. It is shown that the instability of a low-density beam is almost purely quantum in nature and results from the emission of one quantum of a plasma wave-a plasmon-by the beam electrons. The number of emitted (and absorbed) plasmons increases with beam density, so, in the limit of high-density beams, the instability becomes a classical Cherenkov beam instability in plasma. Some analytic solutions and estimates are found, detailed numerical results are obtained, and the evolution of the quantum distribution function of the beam electrons in different regimes of the beam instability is investigated.

Bobylev, Yu. V.; Kuzelev, M. V. [Moscow State University (Russian Federation)

2010-11-15T23:59:59.000Z

84

Quantum Statistical Testing of a QRNG Algorithm  

Science Conference Proceedings (OSTI)

We present the algorithmic design of a quantum random number generator, the subsequent synthesis of a physical design and its verification using quantum statistical testing. We also describe how quantum statistical testing can be used to diagnose channel noise in QKD protocols.

Humble, Travis S [ORNL; Pooser, Raphael C [ORNL; Britt, Keith A [ORNL

2013-01-01T23:59:59.000Z

85

Adiabatic Quantum Simulation of Quantum Chemistry  

E-Print Network (OSTI)

We show how to apply the quantum adiabatic algorithm directly to the quantum computation of molecular properties. We describe a procedure to map electronic structure Hamiltonians to 2-local qubit Hamiltonians with a small set of physically realizable couplings. By combining the Bravyi-Kitaev construction to map fermions to qubits with perturbative gadgets to reduce the Hamiltonian to 2-local, we obtain precision requirements on the coupling strengths and a number of ancilla qubits that scale polynomially in the problem size. Hence our mapping is efficient. The required set of controllable interactions includes only two types of interaction beyond the Ising interactions required to apply the quantum adiabatic algorithm to combinatorial optimization problems. Our mapping may also be of interest to chemists directly as it defines a dictionary from electronic structure to spin Hamiltonians with physical interactions.

Ryan Babbush; Peter J. Love; Alán Aspuru-Guzik

2013-11-15T23:59:59.000Z

86

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

87

Glossary Term - Atomic Number  

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

Particle Previous Term (Alpha Particle) Glossary Main Index Next Term (Avogadro's Number) Avogadro's Number Atomic Number Silver's atomic number is 47 The atomic number is equal to...

88

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

89

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

90

On unentangled Gleason theorems for quantum information theory  

E-Print Network (OSTI)

It is shown here that a strengthening of Wallach's Unentangled Gleason Theorem can be obtained by applying results of the present authors on generalised Gleason theorems for quantum multi-measures arising from investigations of quantum decoherence functionals.

Oliver Rudolph; J. D. M. Wright

2000-04-07T23:59:59.000Z

91

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

92

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

93

Dynamics of quantum discord in the purification process  

E-Print Network (OSTI)

We investigate the dynamics of quantum discord during the purification process. In the case of Werner states, it is shown that quantum discord is increased after a round of purification protocol. We call this process quantum correlation purification in analogy with entanglement purification. Furthermore, quantum mutual information and classical correlation is also increased during this process. We also give an analytic expression for a class of higher dimensional states which have additive quantum discord.

Wei Song; Lin Chen; Ming Yang; Zhuo-Liang Cao

2011-01-13T23:59:59.000Z

94

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

95

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

96

On reconciling quantum mechanics and local realism  

E-Print Network (OSTI)

A necessary and natural change in our application of quantum mechanics to separated systems is shown to reconcile quantum mechanics and local realism. An analysis of separation and localization justifies the proposed change in application of quantum mechanics. An important EPRB experiment is reconsidered and it is seen that when it is correctly interpreted it supports local realism. This reconciliation of quantum mechanics with local realism allows the axiom sets of quantum mechanics, probability, and special relativity to be joined in a consistent global axiom set for physics.

Donald A. Graft

2013-09-04T23:59:59.000Z

97

Entanglement Cost of Quantum Channels  

E-Print Network (OSTI)

The entanglement cost of a quantum channel is the minimal rate at which entanglement (between sender and receiver) is needed in order to simulate many copies of a quantum channel in the presence of free classical communication. In this paper we show how to express this quantity as a regularized optimization of the entanglement formation over states that can be generated between sender and receiver. Our formula is the channel analog of a well-known formula for the entanglement cost of quantum states in terms of the entanglement of formation; and shares a similar relation to the recently shattered hope for additivity. The entanglement cost of a quantum channel can be seen as the analog of the quantum reverse Shannon theorem in the case where free classical communication is allowed. The techniques used in the proof of our result are then also inspired by a recent proof of the quantum reverse Shannon theorem and feature the one-shot formalism for quantum information theory, the post-selection technique for quantum channels as well as von Neumann's minimax theorem. We discuss two applications of our result. First, we are able to link the security in the noisy-storage model to a problem of sending quantum rather than classical information through the adversary's storage device. This not only improves the range of parameters where security can be shown, but also allows us to prove security for storage devices for which no results were known before. Second, our result has consequences for the study of the strong converse quantum capacity. Here, we show that any coding scheme that sends quantum information through a quantum channel at a rate larger than the entanglement cost of the channel has an exponentially small fidelity.

Mario Berta; Fernando Brandao; Matthias Christandl; Stephanie Wehner

2011-08-26T23:59:59.000Z

98

Joint probabilities and quantum cognition  

E-Print Network (OSTI)

In this paper we discuss the existence of joint probability distributions for quantum-like response computations in the brain. We do so by focusing on a contextual neural-oscillator model shown to reproduce the main features of behavioral stimulus-response theory. We then exhibit a simple example of contextual random variables not having a joint probability distribution, and describe how such variables can be obtained from neural oscillators, but not from a quantum observable algebra.

J. Acacio de Barros

2012-06-26T23:59:59.000Z

99

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

100

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

Note: This page contains sample records for the topic "quantum numbers shown" 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

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

102

Parts of Quantum States  

E-Print Network (OSTI)

It is shown that generic N-party pure quantum states (with equidimensional subsystems) are uniquely determined by their reduced states of just over half the parties; in other words, all the information in almost all N-party pure states is in the set of reduced states of just over half the parties. For N even, the reduced states in fewer than N/2 parties are shown to be an insufficient description of almost all states (similar results hold when N is odd). It is noted that Real Algebraic Geometry is a natural framework for any analysis of parts of quantum states: two simple polynomials, a quadratic and a cubic, contain all of their structure. Algorithmic techniques are described which can provide conditions for sets of reduced states to belong to pure or mixed states.

Nick S. Jones; Noah Linden

2004-07-15T23:59:59.000Z

103

Parts of quantum states  

Science Conference Proceedings (OSTI)

It is shown that generic N-party pure quantum states (with equidimensional subsystems) are uniquely determined by their reduced states of just over half the parties; in other words, all the information in almost all N-party pure states is in the set of reduced states of just over half the parties. For N even, the reduced states in fewer than N/2 parties are shown to be an insufficient description of almost all states (similar results hold when N is odd). It is noted that real algebraic geometry is a natural framework for any analysis of parts of quantum states: two simple polynomials, a quadratic and a cubic, contain all of their structure. Algorithmic techniques are described which can provide conditions for sets of reduced states to belong to pure or mixed states.

Jones, Nick S.; Linden, Noah [Department of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW (United Kingdom)

2005-01-01T23:59:59.000Z

104

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

105

From quantum Bayesian inference to quantum tomography  

E-Print Network (OSTI)

We derive an expression for a density operator estimated via Bayesian quantum inference in the limit of an infinite number of measurements. This expression is derived under the assumption that the reconstructed system is in a pure state. In this case the estimation corresponds to an averaging over a generalized microcanonical ensemble of pure states satisfying a set of constraints imposed by the measured mean values of the observables under consideration. We show that via the ``purification'' ansatz, statistical mixtures can also be consistently reconstructed via the quantum Bayesian inference scheme. In this case the estimation corresponds to averaging over the generalized canonical ensemble of states satisfying the given constraints, and the reconstructed density operator maximizes the von Neumann entropy (i.e., this density operator is equal to the generalized canonical density operator which follows from the Jaynes principle of maximum entropy). We study in detail the reconstruction of the spin-1/2 density operator and discuss the logical connection between the three reconstruction schemes, i.e., (1) quantum Bayesian inference, (2) reconstruction via the Jaynes principle of maximum entropy, and (3) discrete quantum tomography.

R. Derka; V. Buzek; G. Adam; P. L. Knight

1997-01-23T23:59:59.000Z

106

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

107

Glossary Term - Avogadro's Number  

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

Atomic Number Previous Term (Atomic Number) Glossary Main Index Next Term (Beta Decay) Beta Decay Avogadro's Number Avogadro's number is the number of particles in one mole of a...

108

Experimental Quantum Process Discrimination  

E-Print Network (OSTI)

Discrimination between unknown processes chosen from a finite set is experimentally shown to be possible even in the case of non-orthogonal processes. We demonstrate unambiguous deterministic quantum process discrimination (QPD) of non-orthogonal processes using properties of entanglement, additional known unitaries, or higher dimensional systems. Single qubit measurement and unitary processes and multipartite unitaries (where the unitary acts non-separably across two distant locations) acting on photons are discriminated with a confidence of $\\geq97%$ in all cases.

Anthony Laing; Terry Rudolph; Jeremy L. O'Brien

2008-01-24T23:59:59.000Z

109

Free motion in deformed (quantum) four-dimensional space  

E-Print Network (OSTI)

It is shown that trajectories of free motion of the particles in deformed ("quantum") four dimensional space-time are quadratic curves.

A. N. Leznov

2007-07-23T23:59:59.000Z

110

The initial momentum dependence of the quantum resonance in the delta-kicked rotor  

E-Print Network (OSTI)

The influence of an initial momentum on the appearance of "quantum resonances" in the delta-kicked rotor system is explored experimentally. We show that for certain initial momenta, a resonance can be negated entirely, whereas at others a resonance can be made to appear. At a larger number of kicks, all resonances are shown to narrow. We show that as a consequence, the individual "diffraction peaks" may split. We compare our results to numerical simulations as well as analytical theory.

J-A. Currivan; A. Ullah; M. D. Hoogerland

2008-06-18T23:59:59.000Z

111

Simultaneous classical-quantum capacities of quantum multiple access channels  

E-Print Network (OSTI)

The rates at which classical and quantum information can be simultaneously transmitted from two spatially separated senders to a single receiver over an arbitrary quantum channel are characterized. Two main results are proved in detail. The first describes the region of rates at which one sender can send classical information while the other sends quantum information. The second describes those rates at which both senders can send quantum information. For each of these situations, an example of a channel is given for which the associated region admits a single-letter description. This is the author's Ph.D. dissertation, submitted to the Department of Electrical Engineering at Stanford University in March, 2005. It represents an expanded version of the paper quant-ph/0501045, containing a number of tutorial chapters which may be of independent interest for those learning about quantum Shannon theory.

Jon Yard

2005-06-06T23:59:59.000Z

112

Light-Matter Quantum Interface  

E-Print Network (OSTI)

We propose a quantum interface which applies multiple passes of a pulse of light through an atomic sample with phase/polarization rotations in between the passes. Our proposal does not require nonclassical light input or measurements on the system, and it predicts rapidly growing unconditional entanglement of light and atoms from just coherent inputs. The proposed interface makes it possible to achieve a number of tasks within quantum information processing including teleportation between light and atoms, quantum memory for light and squeezing of atomic and light variables.

K. Hammerer; K. Molmer; E. S. Polzik; J. I. Cirac

2003-12-18T23:59:59.000Z

113

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

114

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

115

Analysis of limiting information characteristics of quantum-cryptography protocols  

SciTech Connect

The problem of increasing the critical error rate of quantum-cryptography protocols by varying a set of letters in a quantum alphabet for space of a fixed dimensionality is studied. Quantum alphabets forming regular polyhedra on the Bloch sphere and the continual alphabet equally including all the quantum states are considered. It is shown that, in the absence of basis reconciliation, a protocol with the tetrahedral alphabet has the highest critical error rate among the protocols considered, while after the basis reconciliation, a protocol with the continual alphabet possesses the highest critical error rate. (quantum optics and quantum computation)

Sych, D V; Grishanin, Boris A; Zadkov, Viktor N [Department of Physics, M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

2005-01-31T23:59:59.000Z

116

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

117

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

118

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

119

REVIEW OF BARRY MAZUR'S IMAGINING NUMBERS (PARTICULARLY THE SQUARE ROOT OF MINUS FIFTEEN) AND  

E-Print Network (OSTI)

profile in the world's imagination. And it has brought in its train a number of philosophical questions of the explanatory load of quantum mechanics,

Franklin, James

120

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

Note: This page contains sample records for the topic "quantum numbers shown" 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 Knots and Riemann Hypothesis  

E-Print Network (OSTI)

In this paper we propose a quantum gauge system from which we construct generalized Wilson loops which will be as quantum knots. From quantum knots we give a classification table of knots where knots are one-to-one assigned with an integer such that prime knots are bijectively assigned with prime numbers and the prime number 2 corresponds to the trefoil knot. Then by considering the quantum knots as periodic orbits of the quantum system and by the identity of knots with integers and an approach which is similar to the quantum chaos approach of Berry and Keating we derive a trace formula which may be called the von Mangoldt-Selberg-Gutzwiller trace formula. From this trace formula we then give a proof of the Riemann Hypothesis. For our proof of the Riemann Hypothesis we show that the Hilbert-Polya conjecture holds that there is a self-adjoint operator for the nontrivial zeros of the Riemann zeta function and this operator is the Virasoro energy operator with central charge $c=\\frac12$. Our approach for proving the Riemann Hypothesis can also be extended to prove the Extended Riemann Hypothesis. We also investigate the relation of our approach for proving the Riemann Hypothesis with the Random Matrix Theory for $L$-functions.

Sze Kui Ng

2006-03-12T23:59:59.000Z

122

Inequalities for quantum skew information  

E-Print Network (OSTI)

We study quantum information inequalities and show that the basic inequality between the quantum variance and the metric adjusted skew information generates all the multi-operator matrix inequalities or Robertson type determinant inequalities studied by a number of authors. We introduce an order relation on the set of functions representing quantum Fisher information that renders the set into a lattice with an involution. This order structure generates new inequalities for the metric adjusted skew informations. In particular, the Wigner-Yanase skew information is the maximal skew information with respect to this order structure in the set of Wigner-Yanase-Dyson skew informations. Key words and phrases: Quantum covariance, metric adjusted skew information, Robertson-type uncertainty principle, operator monotone function, Wigner-Yanase-Dyson skew information.

Koenraad Audenaert; Liang Cai; Frank Hansen

2008-03-07T23:59:59.000Z

123

Gaussian random number generators  

Science Conference Proceedings (OSTI)

Rapid generation of high quality Gaussian random numbers is a key capability for simulations across a wide range of disciplines. Advances in computing have brought the power to conduct simulations with very large numbers of random numbers and with it, ... Keywords: Gaussian, Random numbers, normal, simulation

David B. Thomas; Wayne Luk; Philip H.W. Leong; John D. Villasenor

2007-11-01T23:59:59.000Z

124

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

125

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

126

Quantum Key Distribution Highly Sensitive to Eavesdropping  

E-Print Network (OSTI)

We introduce a new quantum key distribution protocol that uses d-level quantum systems to encode an alphabet with c letters. It has the property that the error rate introduced by an intercept-and-resend attack tends to one as the numbers c and d increase. In dimension d=2, when the legitimate parties use a complete set of three mutually unbiased bases, the protocol achieves a quantum bit error rate of 57.1%. This represents a significant improvement over the 25% quantum bit error rate achieved in the BB84 protocol or 33% in the six-state protocol.

Brierley, Stephen

2009-01-01T23:59:59.000Z

127

Quantum Key Distribution Highly Sensitive to Eavesdropping  

E-Print Network (OSTI)

We introduce a new quantum key distribution protocol that uses d-level quantum systems to encode an alphabet with c letters. It has the property that the error rate introduced by an intercept-and-resend attack tends to one as the numbers c and d increase. In dimension d=2, when the legitimate parties use a complete set of three mutually unbiased bases, the protocol achieves a quantum bit error rate of 57.1%. This represents a significant improvement over the 25% quantum bit error rate achieved in the BB84 protocol or 33% in the six-state protocol.

Stephen Brierley

2009-10-14T23:59:59.000Z

128

Relativistic Quantum Communication  

E-Print Network (OSTI)

In this Ph.D. thesis, I investigate the communication abilities of non-inertial observers and the precision to which they can measure parametrized states. I introduce relativistic quantum field theory with field quantisation, and the definition and transformations of mode functions in Minkowski, Schwarzschild and Rindler spaces. I introduce information theory by discussing the nature of information, defining the entropic information measures, and highlighting the differences between classical and quantum information. I review the field of relativistic quantum information. We investigate the communication abilities of an inertial observer to a relativistic observer hovering above a Schwarzschild black hole, using the Rindler approximation. We compare both classical communication and quantum entanglement generation of the state merging protocol, for both the single and dual rail encodings. We find that while classical communication remains finite right up to the horizon, the quantum entanglement generation tends to zero. We investigate the observers' abilities to precisely measure the parameter of a state that is communicated between Alice and Rob. This parameter was encoded to either the amplitudes of a single excitation state or the phase of a NOON state. With NOON states the dual rail encoding provided greater precision, which is different to the results for the other situations. The precision was maximum for a particular number of excitations in the NOON state. We calculated the bipartite communication for Alice-Rob and Alice-AntiRob beyond the single mode approximation. Rob and AntiRob are causally disconnected counter-accelerating observers. We found that Alice must choose in advance with whom, Rob or AntiRob she wants to create entanglement using a particular setup. She could communicate classically to both.

Dominic Hosler

2013-06-20T23:59:59.000Z

129

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 ...

130

Covariant Macroscopic Quantum Geometry  

E-Print Network (OSTI)

A covariant noncommutative algebra of position operators is presented, and interpreted as the macroscopic limit of a geometry that describes a collective quantum behavior of the positions of massive bodies in a flat emergent space-time. The commutator defines a quantum-geometrical relationship between world lines that depends on their separation and relative velocity, but on no other property of the bodies, and leads to a transverse uncertainty of the geometrical wave function that increases with separation. The number of geometrical degrees of freedom in a space-time volume scales holographically, as the surface area in Planck units. Ongoing branching of the wave function causes fluctuations in transverse position, shared coherently among bodies with similar trajectories. The theory can be tested using appropriately configured Michelson interferometers.

Hogan, Craig J

2012-01-01T23:59:59.000Z

131

Energy Basics: Photovoltaic Cell Quantum Efficiency  

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

by a photovoltaic (PV) cell to the number of photons-or packets of light-of a given energy shining on the solar cell. Quantum efficiency therefore relates to the response of a...

132

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

133

Quantum field theory without divergences  

E-Print Network (OSTI)

It is shown that loop divergences emerging in the Green functions in quantum field theory originate from correspondence of the Green functions to {\\em unmeasurable} (and hence unphysical) quantities. This is because no physical quantity can be measured in a point, but in a region, the size of which is constrained by the resolution of measuring equipment. The incorporation of the resolution into the definition of quantum fields $\\phi(x)\\to\\phi^{(A)}(x)$ and appropriate change of Feynman rules results in finite values of the Green functions. The Euclidean $\\phi^4$-field theory is taken as an example.

Altaisky, M V

2010-01-01T23:59:59.000Z

134

Quantum field theory without divergences  

E-Print Network (OSTI)

It is shown that loop divergences emerging in the Green functions in quantum field theory originate from correspondence of the Green functions to {\\em unmeasurable} (and hence unphysical) quantities. This is because no physical quantity can be measured in a point, but in a region, the size of which is constrained by the resolution of measuring equipment. The incorporation of the resolution into the definition of quantum fields $\\phi(x)\\to\\phi^{(A)}(x)$ and appropriate change of Feynman rules results in finite values of the Green functions. The Euclidean $\\phi^4$-field theory is taken as an example.

M. V. Altaisky

2010-02-12T23:59:59.000Z

135

Photon-number tomography and fidelity  

E-Print Network (OSTI)

The scheme of photon-number tomography is discussed in the framework of star-product quantization. The connection of dual quantization scheme and observables is reviewed. The quantizer and dequantizer operators and kernels of star product of tomograms in photon-number tomography scheme and its dual one are presented in explicit form. The fidelity and state purity are discussed in photon{number tomographic scheme, and the expressions for fidelity and purity are obtained in the form of integral of the product of two photon-number tomograms with integral kernel which is presented in explicit form. The properties of quantumness are discussed in terms of inequalities on state photon{number tomograms.

O. V. Man'ko

2012-12-23T23:59:59.000Z

136

Strongly Correlated Quantum Fluids: Ultracold Quantum Gases, Quantum Chromodynamic Plasmas, and Holographic Duality  

E-Print Network (OSTI)

Strongly correlated quantum fluids are phases of matter that are intrinsically quantum mechanical, and that do not have a simple description in terms of weakly interacting quasi-particles. Two systems that have recently attracted a great deal of interest are the quark-gluon plasma, a plasma of strongly interacting quarks and gluons produced in relativistic heavy ion collisions, and ultracold atomic Fermi gases, very dilute clouds of atomic gases confined in optical or magnetic traps. These systems differ by more than 20 orders of magnitude in temperature, but they were shown to exhibit very similar hydrodynamic flow. In particular, both fluids exhibit a robustly low shear viscosity to entropy density ratio which is characteristic of quantum fluids described by holographic duality, a mapping from strongly correlated quantum field theories to weakly curved higher dimensional classical gravity. This review explores the connection between these fields, and it also serves as an introduction to the Focus Issue of New Journal of Physics on Strongly Correlated Quantum Fluids: from Ultracold Quantum Gases to QCD Plasmas. The presentation is made accessible to the general physics reader and includes discussions of the latest research developments in all three areas.

Allan Adams; Lincoln D. Carr; Thomas Schaefer; Peter Steinberg; John E. Thomas

2012-05-23T23:59:59.000Z

137

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

138

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

139

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

140

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.

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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
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141

Quantum Algorithms for Quantum Chemistry based on the sparsity of the CI-matrix  

E-Print Network (OSTI)

Quantum chemistry provides a target for quantum simulation of considerable scientific interest and industrial importance. The majority of algorithms to date have been based on a second-quantized representation of the electronic structure Hamiltonian - necessitating qubit requirements that scale linearly with the number of orbitals. The scaling of the number of gates for such methods, while polynomial, presents some serious experimental challenges. However, because the number of electrons is a good quantum number for the electronic structure problem it is unnecessary to store the full Fock space of the orbitals. Representation of the wave function in a basis of Slater determinants for fixed electron number suffices. However, to date techniques for the quantum simulation of the Hamiltonian represented in this basis - the CI-matrix - have been lacking. We show how to apply techniques developed for the simulation of sparse Hamiltonians to the CI-matrix. We prove a number of results exploiting the structure of the CI-matrix, arising from the Slater rules which define it, to improve the application of sparse Hamiltonian simulation techniques in this case. We show that it is possible to use the minimal number of qubits to represent the wavefunction, and that these methods can offer improved scaling in the number of gates required in the limit of fixed electron number and increasing basis set size relevant for high-accuracy calculations. We hope these results open the door to further investigation of sparse Hamiltonian simulation techniques in the context of the quantum simulation of quantum chemistry.

Borzu Toloui; Peter J. Love

2013-12-09T23:59:59.000Z

142

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. Cryptography — the art of code-making — has a long history of military and diplomatic applications, dating back to the Babylonians. In World World Two, the Allies ’ feat of breaking the legendary German code, Enigma, contributed greatly to the final Allied victory. Nowadays, cryptography is becoming increasingly important in commercial applications for electronic business and electronic commerce. Sensitive data such as credit card numbers and personal identification numbers (PINs) are routinely transmitted in encrypted form. Quantum mechanics is a new tool for both code-breakers and code-makers in their eternal arms race. It has the potential to revolutionize cryptography both by creating perfectly secure codes and by breaking standard encryption schemes. The most well-known application of cryptography is secure communication [1]. Suppose Alice would like to send a message to Bob, but there is an eavesdropper, Eve, who is wiretapping the channel. To prevent Eve from knowing the message, Alice and Bob may perform encryption, i.e., transform the message to something that is not intelligible to Eve during the communication. On receiving the message, Bob inverts the transformation and recovers the message (see figure 1). Bob’s advantage over Eve lies in his knowledge of a secret, commonly called the key, that he shares with Alice. The key tells him how to decode the message. For example: The rumble of Soviet tanks shook the Prague hotel room (number 117) as secret agent John Blond finished decoding his orders from his superior N. He tore the used page from the codebook and immediately burned it with his lighter. Blond is using a perfectly unbreakable cipher, a “one-time pad. ” The secret codebook allows N and Blond to share a long secret binary string — the key —

Daniel Gottesman; Hoi-kwong Lo

2000-01-01T23:59:59.000Z

143

Priors in quantum Bayesian inference  

E-Print Network (OSTI)

In quantum Bayesian inference problems, any conclusions drawn from a finite number of measurements depend not only on the outcomes of the measurements but also on a prior. Here we show that, in general, the prior remains important even in the limit of an infinite number of measurements. We illustrate this point with several examples where two priors lead to very different conclusions given the same measurement data.

Christopher A. Fuchs; Ruediger Schack

2009-06-09T23:59:59.000Z

144

Quantum Reality, Complex Numbers, and the Meteorological Butterfly Effect  

Science Conference Proceedings (OSTI)

Meteorology is a wonderfully interdisciplinary subject. But can nonlinear thinking about predictability of weather and climate contribute usefully to issues in fundamental physics? Although this might seem extremely unlikely at first sight, ...

T. N. Palmer

2005-04-01T23:59:59.000Z

145

Quantum mechanics needs no interpretation  

E-Print Network (OSTI)

Probabilistic description of results of measurements and its consequences for understanding quantum mechanics are discussed. It is shown that the basic mathematical structure of quantum mechanics like the probability amplitude, Born rule, probability density current, commutation relations, momentum operator, uncertainty relations, rules for including the scalar and vector potentials and existence of antiparticles can be derived from the definition of the mean values of the space coordinates and time. Equations of motion of quantum mechanics, the Klein-Gordon equation, Schroedinger equation and Dirac equation are obtained from requirement of the relativistic invariance of the theory. Limit case of localized probability densities leads to the Hamilton-Jacobi equation of classical mechanics. Many particle systems are also discussed.

L. Skala; V. Kapsa

2004-12-22T23:59:59.000Z

146

Quadratic control of quantum processes  

E-Print Network (OSTI)

Within the framework of the Accardi-Fagnola-Quaegebeur (AFQ) representation free calculus of \\cite{b}, we consider the problem of controlling the size of a quantum stochastic flow generated by a unitary stochastic evolution affected by quantum noise. In the case when the evolution is driven by first order white noise (which includes quantum Brownian motion) the control is shown to be given in terms of the solution of an algebraic Riccati equation. This is done by first solving the problem of controlling (by minimizing an associated quadratic performance criterion) a stochastic process whose evolution is described by a stochastic differential equation of the type considerd in \\cite{b}. The solution is given as a feedback control law in terms of the solution of a stochastic Riccati equation.

Luigi Accardi; Andreas Boukas

2013-08-07T23:59:59.000Z

147

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

148

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

149

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.

150

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

151

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

152

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

153

Quantum rotor theory of spinor condensates in tight traps  

Science Conference Proceedings (OSTI)

In this work, we theoretically construct exact mappings of many-particle bosonic systems onto quantum rotor models. In particular, we analyze the rotor representation of spinor Bose-Einstein condensates. In a previous work [R. Barnett et al., Phys. Rev. A 82, 031602(R) (2010)] it was shown that there is an exact mapping of a spin-one condensate of fixed particle number with quadratic Zeeman interaction onto a quantum rotor model. Since the rotor model has an unbounded spectrum from above, it has many more eigenstates than the original bosonic model. Here we show that for each subset of states with fixed spin F{sub z}, the physical rotor eigenstates are always those with the lowest energy. We classify three distinct physical limits of the rotor model: the Rabi, Josephson, and Fock regimes. The last regime corresponds to a fragmented condensate and is thus not captured by the Bogoliubov theory. We next consider the semiclassical limit of the rotor problem and make connections with the quantum wave functions through the use of the Husimi distribution function. Finally, we describe how to extend the analysis to higher-spin systems and derive a rotor model for the spin-two condensate. Theoretical details of the rotor mapping are also provided here.

Barnett, Ryan; Hui, Hoi-Yin; Lin, Chien-Hung; Sau, Jay D.; Das Sarma, S. [Joint Quantum Institute and Condensed Matter Theory Center, Department of Physics, University of Maryland, College Park, Maryland 20742-4111 (United States)

2011-02-15T23:59:59.000Z

154

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

155

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. ...

Hogan, Craig J

2007-01-01T23:59:59.000Z

156

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

157

Is Quantum Logic a Logic?  

E-Print Network (OSTI)

It is shown that quantum logic is a logic in the very same way in which classical logic is a logic. Soundness and completeness of both quantum and classical logics have been proved for novel lattice models that are not orthomodular and therefore cannot be distributive either - as opposed to the standard lattice models that are orthomodular and distributive for the respective logics. Hence, we cannot attribute the orthomodularity to quantum logic itself, and we cannot attribute the distributivity to classical logic itself. The valuations of logics with respect of novel models turn out to be non-numerical, and therefore truth values and truth tables cannot in general be ascribed to the propositions of logics themselves but only to the variables of some of their models -for example, the two-valued Boolean algebra. Logics are, first of all, axiomatic deductive systems, and if we stop short of considering their semantics (models, valuations, etc.), then both quantum and classical logics will have a completely equal footing in the sense of being two deductive systems that differ from each other in a few axioms and nothing else. There is no ground for considering either of the two logics more "proper" than the other. Semantics of these logics belong to their models, and we show that there are bigger differences between the two aforementioned classical models than between two corresponding quantum and classical models.

Mladen Pavicic; Norman D. Megill

2008-12-15T23:59:59.000Z

158

A quantum model for the stock market  

E-Print Network (OSTI)

Beginning with several basic hypotheses of quantum mechanics, we give a new quantum model in econophysics. In this model, we define wave functions and operators of the stock market to establish the Schr\\"odinger equation for the stock price. Based on this theoretical framework, an example of a driven infinite quantum well is considered, in which we use a cosine distribution to simulate the state of stock price in equilibrium. After adding an external field into the Hamiltonian to analytically calculate the wave function, the distribution and the average value of the rate of return are shown.

Chao Zhang; Lu Huang

2010-09-24T23:59:59.000Z

159

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

160

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

Note: This page contains sample records for the topic "quantum numbers shown" 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

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

162

Quantum Gravity at the LHC  

E-Print Network (OSTI)

It has recently been shown that if there is a large hidden sector in Nature, the scale of quantum gravity could be much lower than traditionally expected. We study the production of massless gravitons at the LHC and compare our results to those obtained in extra dimensional models. The signature in both cases is missing energy plus jets. In case of non observation, the LHC could be used to put the tightest limit to date on the value of the Planck mass.

Xavier Calmet; Priscila de Aquino

2009-06-02T23:59:59.000Z

163

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

164

Joint probabilities and quantum cognition  

SciTech Connect

In this paper we discuss the existence of joint probability distributions for quantumlike response computations in the brain. We do so by focusing on a contextual neural-oscillator model shown to reproduce the main features of behavioral stimulus-response theory. We then exhibit a simple example of contextual random variables not having a joint probability distribution, and describe how such variables can be obtained from neural oscillators, but not from a quantum observable algebra.

Acacio de Barros, J. [Liberal Studies, 1600 Holloway Ave., San Francisco State University, San Francisco, CA 94132 (United States)

2012-12-18T23:59:59.000Z

165

Texas Natural Gas Number of Industrial Consumers (Number of Elements...  

Annual Energy Outlook 2012 (EIA)

View History: Annual Download Data (XLS File) Texas Natural Gas Number of Industrial Consumers (Number of Elements) Texas Natural Gas Number of Industrial Consumers (Number of...

166

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

167

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

168

The quantum capacity of channels with arbitrarily correlated noise  

E-Print Network (OSTI)

We study optimal rates for quantum communication over a single use of a channel, which itself can correspond to a finite number of uses of a channel with arbitrarily correlated noise. The corresponding capacity is often referred to as the one-shot quantum capacity. In this paper, we prove bounds on the one-shot quantum capacity of an arbitrary channel. This allows us to compute the quantum capacity of a channel with arbitrarily correlated noise, in the limit of asymptotically many uses of the channel. In the memoryless case, we explicitly show that our results reduce to known expressions for the quantum capacity.

Francesco Buscemi; Nilanjana Datta

2009-02-02T23:59:59.000Z

169

Number | Department of Energy  

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

Number More Documents & Publications Analysis of Open Office of Inspector General Recommendations, OAS-L-08-07 Policy and International Affairs (WFP) Open Government Plan 2.0...

170

Expected Frobenius numbers  

E-Print Network (OSTI)

We show that for large instances the order of magnitude of the expected Frobenius number is (up to a constant depending only on the dimension) given by its lower bound.

Aliev, Iskander; Hinrichs, Aicke

2009-01-01T23:59:59.000Z

171

Quantum state estimation with unknown measurements  

E-Print Network (OSTI)

Improved measurement techniques are central to technological development and foundational scientific exploration. Quantum optics relies upon detectors sensitive to non-classical features of light, enabling precise tests of physical laws and quantum-enhanced technologies such as precision measurement and secure communications. Accurate detector response calibration for quantum-scale inputs is key to future research and development in these cognate areas. To address this requirement quantum detector tomography (QDT) has been recently introduced. However, the QDT approach becomes increasingly challenging as the complexity of the detector response and input space grows. Here we present the first experimental implementation of a versatile alternative characterization technique to address many-outcome quantum detectors by limiting the input calibration region. To demonstrate the applicability of this approach the calibrated detector is subsequently used to estimate non-classical photon number states.

Merlin Cooper; Michal Karpinski; Brian J. Smith

2013-06-27T23:59:59.000Z

172

Mode Competition in Dual-Mode Quantum Dots Semiconductor Microlaser  

E-Print Network (OSTI)

This paper describes the modeling of quantum dots lasers with the aim of assessing the conditions for stable cw dual-mode operation when the mode separation lies in the THz range. Several possible models suited for InAs quantum dots in InP barriers are analytically evaluated, in particular quantum dots electrically coupled through a direct exchange of excitation by the wetting layer or quantum dots optically coupled through the homogeneous broadening of their optical gain. A stable dual-mode regime is shown possible in all cases when quantum dots are used as active layer whereas a gain medium of quantum well or bulk type inevitably leads to bistable behavior. The choice of a quantum dots gain medium perfectly matched the production of dual-mode lasers devoted to THz generation by photomixing.

Chusseau, Laurent; Viktorovitch, P; Letartre, Xavier

2013-01-01T23:59:59.000Z

173

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

174

Quantum probabilities of composite events in quantum measurements with multimode states  

E-Print Network (OSTI)

The problem of defining quantum probabilities of composite events is considered. This problem is of high importance for the theory of quantum measurements and for quantum decision theory that is a part of measurement theory. We show that the Luders probability of consecutive measurements is a transition probability between two quantum states and that this probability cannot be treated as a quantum extension of the classical conditional probability. The Wigner distribution is shown to be a weighted transition probability that cannot be accepted as a quantum extension of the classical joint probability. We suggest the definition of quantum joint probabilities by introducing composite events in multichannel measurements. The notion of measurements under uncertainty is defined. We demonstrate that the necessary condition for the mode interference is the entanglement of the composite prospect together with the entanglement of the composite statistical state. As an illustration, we consider an example of a quantum game. A special attention is payed to the application of the approach to systems with multimode states, such as atoms, molecules, quantum dots, or trapped Bose-condensed atoms with several coherent modes.

V. I. Yukalov; D. Sornette

2013-08-26T23:59:59.000Z

175

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

176

Finite size scaling for quantum criticality using the finite-element method  

E-Print Network (OSTI)

Finite size scaling for the Schr\\"{o}dinger equation is a systematic approach to calculate the quantum critical parameters for a given Hamiltonian. This approach has been shown to give very accurate results for critical parameters by using a systematic expansion with global basis-type functions. Recently, the finite element method was shown to be a powerful numerical method for ab initio electronic structure calculations with a variable real-space resolution. In this work, we demonstrate how to obtain quantum critical parameters by combining the finite element method (FEM) with finite size scaling (FSS) using different ab initio approximations and exact formulations. The critical parameters could be atomic nuclear charges, internuclear distances, electron density, disorder, lattice structure, and external fields for stability of atomic, molecular systems and quantum phase transitions of extended systems. To illustrate the effectiveness of this approach we provide detailed calculations of applying FEM to approximate solutions for the two-electron atom with varying nuclear charge; these include Hartree-Fock, density functional theory under the local density approximation, and an "exact"' formulation using FEM. We then use the FSS approach to determine its critical nuclear charge for stability; here, the size of the system is related to the number of elements used in the calculations. Results prove to be in good agreement with previous Slater-basis set calculations and demonstrate that it is possible to combine finite size scaling with the finite-element method by using ab initio calculations to obtain quantum critical parameters. The combined approach provides a promising first-principles approach to describe quantum phase transitions for materials and extended systems.

Edwin Antillon; Birgit Wehefritz-Kaufmann; Sabre Kais

2011-09-12T23:59:59.000Z

177

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

178

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

179

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

180

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

Note: This page contains sample records for the topic "quantum numbers shown" 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

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

182

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

183

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

184

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

185

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

186

Report number codes  

SciTech Connect

This publication lists all report number codes processed by the Office of Scientific and Technical Information. The report codes are substantially based on the American National Standards Institute, Standard Technical Report Number (STRN)-Format and Creation Z39.23-1983. The Standard Technical Report Number (STRN) provides one of the primary methods of identifying a specific technical report. The STRN consists of two parts: The report code and the sequential number. The report code identifies the issuing organization, a specific program, or a type of document. The sequential number, which is assigned in sequence by each report issuing entity, is not included in this publication. Part I of this compilation is alphabetized by report codes followed by issuing installations. Part II lists the issuing organization followed by the assigned report code(s). In both Parts I and II, the names of issuing organizations appear for the most part in the form used at the time the reports were issued. However, for some of the more prolific installations which have had name changes, all entries have been merged under the current name.

Nelson, R.N. (ed.)

1985-05-01T23:59:59.000Z

187

Indeterminacy of Quantum Geometry  

E-Print Network (OSTI)

An effective theory of quantum spacetime geometry based on wave optics is used to describe fundamental limits on propagation and measurement of information in holographic spacetimes. Wavefunctions describing spacetime event positions are modeled as complex disturbances of quasi-monochromatic Planck wavelength radiation. The transverse position on a two-dimensional geometrical wavefront, represented by the optical complex degree of coherence, is related to a prepared state represented by a transverse distribution of intensity on an initial wavefront. The transverse position distributions describing two macroscopically null-separated events are shown to approximate Fourier transforms of each other. This relationship is interpreted as an uncertainty inherent to spacetime: the product of standard deviations of transverse position of two events is equal to the product of their separation and the Planck length. For macroscopically separated events the uncertainty is much larger than the Planck length, and is predic...

Hogan, Craig J

2008-01-01T23:59:59.000Z

188

Markov’s maximon and quantum black holes  

Science Conference Proceedings (OSTI)

It is shown that the modern theory predicts the existence of a minimum mass of quantum black holes. Such minimal black holes are a natural candidate for the maximon

V. A. Berezin

1998-01-01T23:59:59.000Z

189

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

190

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 Prástaro

2011-05-01T23:59:59.000Z

191

Number | Open Energy Information  

Open Energy Info (EERE)

Number Number Jump to: navigation, search Properties of type "Number" Showing 200 properties using this type. (previous 200) (next 200) A Property:AvgAnnlGrossOpCpcty Property:AvgTempGeoFluidIntoPlant Property:AvgWellDepth B Property:Building/FloorAreaChurchesChapels Property:Building/FloorAreaGroceryShops Property:Building/FloorAreaHealthServices24hr Property:Building/FloorAreaHealthServicesDaytime Property:Building/FloorAreaHeatedGarages Property:Building/FloorAreaHotels Property:Building/FloorAreaMiscellaneous Property:Building/FloorAreaOffices Property:Building/FloorAreaOtherRetail Property:Building/FloorAreaResidential Property:Building/FloorAreaRestaurants Property:Building/FloorAreaSchoolsChildDayCare Property:Building/FloorAreaShops Property:Building/FloorAreaSportCenters

192

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

193

Directional Entanglement of Quantum Fields with Quantum Geometry  

E-Print Network (OSTI)

A modification of quantum field theory on large scales is conjectured to result from effects of Planck scale limits on directional information. Transversely localized solutions of the relativistic wave equation are used to show that the path of a massless particle with wavelength $\\lambda$ that travels a distance $z$ has a wave function with indeterminacy in direction given by the diffraction scale, $\\langle \\Delta \\theta^2\\rangle > \\sqrt{2}\\lambda /\\pi z$. It is conjectured that the spatial structure of all quantum field states is influenced by a new kind of directional indeterminacy of quantum geometry set by the Planck length, $l_P$, that does not occur in the usual classical background geometry. Entanglement of field and geometry states is described in the small angle approximation. It is shown to have almost no effect on local measurements, microscopic particle interactions, or measurements of propagating states that depend only on longitudinal coordinates, but to significantly alter field states in systems larger than $\\approx \\lambda^2/l_P $ that depend on transverse coordinates or direction. It reduces the information content of fields in large systems, consistent with holographic bounds from gravitation theory, and may lead to quantum-geometrical directional fluctuations of massive bodies detectable with interferometers. Possible connections are discussed with field vacuum energy, black hole information, and inflationary fluctuations.

Craig J. Hogan

2013-12-30T23:59:59.000Z

194

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

195

The capacity of hybrid quantum memory  

E-Print Network (OSTI)

The general stable quantum memory unit is a hybrid consisting of a classical digit with a quantum digit (qudit) assigned to each classical state. The shape of the memory is the vector of sizes of these qudits, which may differ. We determine when N copies of a quantum memory A embed in N(1+o(1)) copies of another quantum memory B. This relationship captures the notion that B is as at least as useful as A for all purposes in the bulk limit. We show that the embeddings exist if and only if for all p >= 1, the p-norm of the shape of A does not exceed the p-norm of the shape of B. The log of the p-norm of the shape of A can be interpreted as the maximum of S(\\rho) + H(\\rho)/p (quantum entropy plus discounted classical entropy) taken over all mixed states \\rho on A. We also establish a noiseless coding theorem that justifies these entropies. The noiseless coding theorem and the bulk embedding theorem together say that either A blindly bulk-encodes into B with perfect fidelity, or A admits a state that does not visibly bulk-encode into B with high fidelity. In conclusion, the utility of a hybrid quantum memory is determined by its simultaneous capacity for classical and quantum entropy, which is not a finite list of numbers, but rather a convex region in the classical-quantum entropy plane.

Greg Kuperberg

2002-03-21T23:59:59.000Z

196

Using Fractional Numbers of . . .  

E-Print Network (OSTI)

One of the design parameters in closed queueing networks is Np, the number of customers of class p. It has been assumed that Np must be an integer. However, integer choices will usually not achieve the target throughput for each class simultaneously. We use Mean Value Analysis with the Schweitzer-Bard approximation and nonlinear programming to determine the value of Np needed to achieve the production targets exactly, although the values of Np may be fractional. We interpret these values to represent the average number of customers of each class in the network. We implement a control rule to achieve these averages and verify our approach through simulation.

Rajan Suri; Rahul Shinde; Mary Vernon

2005-01-01T23:59:59.000Z

197

Mass gap in quantum energy-mass spectrum of relativistic Yang-Mills fields  

E-Print Network (OSTI)

A relativistic quantum Yang-Mills theory with a simple compact gauge Lie group on the four-dimensional Minkowski spacetime is set up in a framework of infinite-dimensional pseudodifferential operators in a nuclear Kree-Gelfand triple. The linear quantum Yang-Mills energy-mass operator is defined as the anti-normal quantization of the non-linear Yang-Mills energy-mass functional of consrained Cauchy data supported by an euclidean ball of a radius R. It is shown that expectation functional of the Yang-Mills energy-mass operator majorises the expectation functional of a scaled occupation number operator so that, by variational spectral principles, the quantum Yang-Mills spectral mass gap is positive. The mass gap is proportional to 1/R. The running coupling constant is proportional to the square root of R, leading to an asymptotic freedom for quantum Yang-Mills theory at short distances. This mathematically rigorous theory is non-perturbative and provides a solution for the 7th Clay Institute Millennium problem.

Alexander Dynin

2013-08-29T23:59:59.000Z

198

A number of organizations,  

E-Print Network (OSTI)

buying power to purchase green power. The city of Chicago has formed an alliance with 47 other local installed solar electric systems on a number of the city's buildings, including the Chicago Center for Green to competition, the city of Chicago and 47 other local government agencies formed the Local Government Power

199

CHEMICAL SAFETY Emergency Numbers  

E-Print Network (OSTI)

- 1 - CHEMICAL SAFETY MANUAL 2010 #12;- 2 - Emergency Numbers UNBC Prince George Campus Security Prince George Campus Chemstores 6472 Chemical Safety 6472 Radiation Safety 5530 Biological Safety 5530 use, storage, handling, waste and emergency management of chemicals on the University of Northern

Bolch, Tobias

200

Disjunctive Rado numbers  

Science Conference Proceedings (OSTI)

If L1 and L2 are linear equations, then the disjunctive Rado number of the set {L1, L2} is the least integer n, provided that it exists, such that for every 2-coloring of ... Keywords: Rado, Ramsey, Schur, disjunctive

Brenda Johnson; Daniel Schaal

2005-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "quantum numbers shown" 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

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

202

Adiabatic quantum state transfer in non-uniform triple-quantum-dot system  

E-Print Network (OSTI)

We introduce an adiabatic quantum state transfer scheme in a non-uniform coupled triple-quantum-dot system. By adiabatically varying the external gate voltage applied on the sender and receiver, the electron can be transferred between them with high fidelity. By numerically solving the master equation for a system with always-on interaction, it is indicated that the transfer fidelity depends on the ration between the peak voltage and the maximum coupling constants. The effect of coupling mismatch on the transfer fidelity is also investigated and it is shown that there is a relatively large tolerance range to permit high fidelity quantum state transfer.

Bing Chen; Wei Fan; Yan Xu

2010-10-18T23:59:59.000Z

203

Is Quantum Logic a Logic?  

E-Print Network (OSTI)

It is shown that quantum logic is a logic in the very same way in which classical logic is a logic. Soundness and completeness of both quantum and classical logics have been proved for novel lattice models that are not orthomodular and therefore cannot be distributive either - as opposed to the standard lattice models that are orthomodular and distributive for the respective logics. Hence, we cannot attribute the orthomodularity to quantum logic itself, and we cannot attribute the distributivity to classical logic itself. The valuations of logics with respect of novel models turn out to be non-numerical, and therefore truth values and truth tables cannot in general be ascribed to the propositions of logics themselves but only to the variables of some of their models -for example, the two-valued Boolean algebra. Logics are, first of all, axiomatic deductive systems, and if we stop short of considering their semantics (models, valuations, etc.), then both quantum and classical logics will have a completely equa...

Pavicic, Mladen

2008-01-01T23:59:59.000Z

204

A new approach to quantum gravity  

E-Print Network (OSTI)

A new idea of quantum gravity is developed based on Gravitational Complementary Principle. This principle states that gravity has dual complement features: The quantum and classical aspects of gravity are complement and absolutely separated by the planck length into planckian and over-planckian domains, respectively. The classical Einstein equations are correct at the fundamental level at over-planckian domain and general relativity is not a low energy limit of a more fundamental theory. The quantum gravity is totally confined to the planckian domain with a new kind of ultra-short range interaction, mediated by massive (Planck mass) particles, through the virtual microscopic wormholes of the Planck scale with action ¯h. There is no room for gravitons or extra dimensions in ?e-mail:f.darabi@azaruniv.edu 1this scenario. It is shown that the hierarchy problem can solve the cosmological constant problem via this new quantum gravity. 2 1

F. Darabi

2008-01-01T23:59:59.000Z

205

Structure of propagators for quantum nondemolition systems  

E-Print Network (OSTI)

In the scheme of a quantum nondemolition (QND) measurement, an observable is measured without perturbing its evolution. In the context of studies of decoherence in quantum computing, we examine the `open' quantum system of a two-level atom, or equivalently, a spin-1/2 system, in interaction with quantum reservoirs of either oscillators or spins, under the QND condition of the Hamiltonian of the system commuting with the system-reservoir interaction. The propagators for these QND Hamiltonians are shown to be connected to the squeezing and rotation operators for the two baths, respectively. Squeezing and rotation being both phase space area-preserving canonical transformations, this brings out an interesting analogy between the energy-preserving QND Hamiltonians and the homogeneous linear canonical transformations.

Subhashish Banerjee; R. Ghosh

2006-11-11T23:59:59.000Z

206

South Dakota Natural Gas Number of Commercial Consumers (Number...  

Gasoline and Diesel Fuel Update (EIA)

View History: Annual Download Data (XLS File) South Dakota Natural Gas Number of Commercial Consumers (Number of Elements) South Dakota Natural Gas Number of Commercial Consumers...

207

South Dakota Natural Gas Number of Residential Consumers (Number...  

Annual Energy Outlook 2012 (EIA)

View History: Annual Download Data (XLS File) South Dakota Natural Gas Number of Residential Consumers (Number of Elements) South Dakota Natural Gas Number of Residential...

208

South Dakota Natural Gas Number of Industrial Consumers (Number...  

U.S. Energy Information Administration (EIA) Indexed Site

View History: Annual Download Data (XLS File) South Dakota Natural Gas Number of Industrial Consumers (Number of Elements) South Dakota Natural Gas Number of Industrial Consumers...

209

Quantum circuit optimization by topological compaction in the surface code  

E-Print Network (OSTI)

The fragile nature of quantum information limits our ability to construct large quantities of quantum bits suitable for quantum computing. An important goal, therefore, is to minimize the amount of resources required to implement quantum algorithms, many of which are serial in nature and leave large numbers of qubits idle much of the time unless compression techniques are used. Furthermore, quantum error-correcting codes, which are required to reduce the effects of noise, introduce additional resource overhead. We consider a strategy for quantum circuit optimization based on topological deformation in the surface code, one of the best performing and most practical quantum error-correcting codes. Specifically, we examine the problem of minimizing computation time on a two-dimensional qubit lattice of arbitrary, but fixed dimension, and propose two algorithms for doing so.

Adam Paetznick; Austin G. Fowler

2013-04-09T23:59:59.000Z

210

Preventive Action Number:  

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

7 Corrective Action Report Planning Worksheet 11_0414 1 of 3 7 Corrective Action Report Planning Worksheet 11_0414 1 of 3 EOTA - Business Form Document Title: Corrective Action Report Planning Worksheet Document Number: F-017 Rev 11_0414 Document Owner: Elizabeth Sousa Backup Owner: Melissa Otero Approver(s): Melissa Otero Parent Document: P-008, Corrective/Preventive Action Notify of Changes: EOTA Employees Referenced Document(s): N/A F-017 Corrective Action Report Planning Worksheet 11_0414 2 of 3 Revision History: Rev. Description of Change 08_0613 Initial Release 11_0414 Added problem statement to first block. F-017 Corrective Action Report Planning Worksheet 11_0414 3 of 3 Corrective Action Report Planning Worksheet Corrective Action Number: Source: Details/Problem Statement: Raised By: Raised Date: Target Date:

211

ELECTRICAL DISTRICT NUMBER EIGHT  

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

ELECTRICAL DISTRICT NUMBER EIGHT ELECTRICAL DISTRICT NUMBER EIGHT Board of Directors Reply to: Ronald Rayner C. W. Adams James D. Downing, P.E. Chairman Billy Hickman 66768 Hwy 60 Brian Turner Marvin John P.O. Box 99 Vice-Chairman Jason Pierce Salome, AZ 85348 Denton Ross Jerry Rovey Secretary James N. Warkomski ED8@HARCUVARCO.COM John Utz Gary Wood PHONE:(928) 859-3647 Treasurer FAX: (928) 859-3145 Sent via e-mail Mr. Darrick Moe, Regional Manager Western Area Power Administration Desert Southwest Region P. O. Box 6457 Phoenix, AZ 85005-6457 moe@wapa.gov; dswpwrmrk@wapa.gov Re: ED5-Palo Verde Hub Project Dear Mr. Moe, In response to the request for comments issued at the October 6 Parker-Davis Project customer th meeting, and in conjunction with comments previously submitted by the Southwest Public Power

212

Preventive Action Number:  

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

8 Preventive Action Report Planning Worksheet 11_0414 1 of 3 8 Preventive Action Report Planning Worksheet 11_0414 1 of 3 EOTA - Business Form Document Title: Preventive Action Report Planning Worksheet Document Number: F-018 Rev 11_0414 Document Owner: Elizabeth Sousa Backup Owner: Melissa Otero Approver(s): Melissa Otero Parent Document: P-008, Corrective/Preventive Action Notify of Changes: EOTA Employees Referenced Document(s): N/A F-018 Preventive Action Report Planning Worksheet 11_0414 2 of 3 Revision History: Rev. Description of Change 08_0613 Initial Release 09_0924 Worksheet modified to reflect External Audit recommendation for identification of "Cause for Potential Nonconformance". Minor editing changes. 11_0414 Added Preventive Action Number block to match Q-Pulse

213

Quantum kinetic theory model of a continuous atom laser  

E-Print Network (OSTI)

We investigate the feasible limits for realising a continuously evaporated atom laser with high-temperature sources. A plausible scheme for realising a truly continuous atom laser is to outcouple atoms from a partially condensed Bose gas, whilst continuously reloading the system with non-condensed thermal atoms and performing evaporative cooling. Here we use quantum kinetic theory to model this system and estimate feasible limits for the operation of such a scheme. For sufficiently high temperatures, the figure of merit for the source is shown to be the phase-space flux. The dominant process limiting the usage of sources with low phase-space flux is the three-body loss of the condensed gas. We conclude that certain double-magneto-optical trap (MOT) sources may produce substantial mean condensate numbers through continuous evaporation, and provide an atom laser source with a narrow linewidth and reasonable flux.

G. R. Dennis; Matthew J. Davis; J. J. Hope

2010-11-24T23:59:59.000Z

214

Improving the efficiency of decoding quantum error correction code  

E-Print Network (OSTI)

To improve the efficiency of the encoding and the decoding is the important problem in the quantum error correction. In a preceding work, a general algorithm for decoding the stabilizer code is shown. This paper will show an decoding which is more efficient for some codes. The proposed decoding as well as the conventional decoding consists of the eigenvalue output step and the entanglement dissolution step. The proposed decoding outputs a part of the eigenvalues into a part of the code qubits in contrast to the conventional method's outputting into the ancilla. Besides, the proposed decoding dissolves a part of the entanglement in the eigenvalue output step in contrast to the conventional method which does not dissolve in the eigenvalue output step. With these improvements, the number of gates was reduced for some codes.

Kenichiro Furuta

2006-08-21T23:59:59.000Z

215

Improving the efficiency of decoding quantum error correction code  

E-Print Network (OSTI)

To improve the efficiency of the encoding and the decoding is the important problem in the quantum error correction. In a preceding work, a general algorithm for decoding the stabilizer code is shown. This paper will show an decoding which is more efficient for some codes. The proposed decoding as well as the conventional decoding consists of the eigenvalue output step and the entanglement dissolution step. The proposed decoding outputs a part of the eigenvalues into a part of the code qubits in contrast to the conventional method's outputting into the ancilla. Besides, the proposed decoding dissolves a part of the entanglement in the eigenvalue output step in contrast to the conventional method which does not dissolve in the eigenvalue output step. With these improvements, the number of gates was reduced for some codes.

Furuta, K

2006-01-01T23:59:59.000Z

216

Energy Content of Quantum Systems and the Alleged Collapse of the Wavefunction  

E-Print Network (OSTI)

It is shown that within a quantum system, the wave field has a (potential) energy content that can be exchanged with quantum particles. Energy conservation in quantum systems holds if potential energy is correctly taken to be a field attribute. From this perspective, a transfer of energy occurs on measurement from the wave field to a quantum particle and this provides a physical explanation of what is commonly referred to as the collapse of the wavefunction.

Peter J. Riggs

2009-10-15T23:59:59.000Z

217

Chern numbers hiding in time-of-flight images  

SciTech Connect

We present a technique for detecting topological invariants--Chern numbers--from time-of-flight images of ultracold atoms. We show that the Chern numbers of integer quantum Hall states of lattice fermions leave their fingerprints in the atoms' momentum distribution. We analytically demonstrate that the number of local maxima in the momentum distribution is equal to the Chern number in two limiting cases, for large hopping anisotropy and in the continuum limit. In addition, our numerical simulations beyond these two limits show that these local maxima persist for a range of parameters. Thus, an everyday observable in cold atom experiments can serve as a useful tool to characterize and visualize quantum states with nontrivial topology.

Zhao Erhai; Satija, Indubala I. [School of Physics, Astronomy, and Computational Sciences, George Mason University, Fairfax, Virginia 22030 (United States); Joint Quantum Institute, National Institute of Standards and Technology and University of Maryland, Gaithersburg, Maryland 20899 (United States); Bray-Ali, Noah; Williams, Carl J.; Spielman, I. B. [Joint Quantum Institute, National Institute of Standards and Technology and University of Maryland, Gaithersburg, Maryland 20899 (United States)

2011-12-15T23:59:59.000Z

218

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

219

A Quantum Particle Undergoing Continuous Observation  

E-Print Network (OSTI)

A stochastic model for the continuous nondemolition ohservation of the position of a quantum particle in a potential field and a boson reservoir is given. lt is shown that any Gaussian wave function evolving according to the posterior wave equation with a quadratic potential collapses to a Gaussian wave packet given by the stationary solution of this equation.

V. P. Belavkin; P. Staszewski

2005-12-17T23:59:59.000Z

220

Entanglement Distillation Protocols and Number Theory  

E-Print Network (OSTI)

We show that the analysis of entanglement distillation protocols for qudits of arbitrary dimension $D$ benefits from applying basic concepts from number theory, since the set $\\zdn$ associated to Bell diagonal states is a module rather than a vector space. We find that a partition of $\\zdn$ into divisor classes characterizes the invariant properties of mixed Bell diagonal states under local permutations. We construct a very general class of recursion protocols by means of unitary operations implementing these local permutations. We study these distillation protocols depending on whether we use twirling operations in the intermediate steps or not, and we study them both analitically and numerically with Monte Carlo methods. In the absence of twirling operations, we construct extensions of the quantum privacy algorithms valid for secure communications with qudits of any dimension $D$. When $D$ is a prime number, we show that distillation protocols are optimal both qualitatively and quantitatively.

H. Bombin; M. A. Martin-Delgado

2005-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "quantum numbers shown" 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

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

222

Quantum dynamics in dual spaces  

Science Conference Proceedings (OSTI)

Quantum mechanics gives us information about spectra of dynamical variables and transition rates including scattering cross sections. They can be exhibited as spectral information in analytically continued spaces and their duals. Quantum mechanics formulated in these generalized spaces is used to study scattering and time evolution. It is shown that the usual asymptotic condition is inadequate to deal with scattering of composite or unstable particles. Scattering theory needs amendment when the interacting system is not isospectral with the free Hamiltonian, and the amendment is formulated. Perturbation theory in generalized spaces is developed and used to study the deletion and augmentation of the spectrum of the Hamiltonian. A complete set of algebraically independent constants for an interacting system is obtained. The question of the breaking of time symmetry is discussed.

Sudarshan, E.C.G.

1993-12-31T23:59:59.000Z

223

Finite Neutrosophic Complex Numbers  

E-Print Network (OSTI)

In this book for the first time the authors introduce the notion of real neutrosophic complex numbers. Further the new notion of finite complex modulo integers is defined. For every $C(Z_n)$ the complex modulo integer $i_F$ is such that $2F_i = n - 1$. Several algebraic structures on $C(Z_n)$ are introduced and studied. Further the notion of complex neutrosophic modulo integers is introduced. Vector spaces and linear algebras are constructed using these neutrosophic complex modulo integers.

W. B. Vasantha Kandasamy; Florentin Smarandache

2011-11-01T23:59:59.000Z

224

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. Martín-Ruiz; J. Bernal; Adrián Carbajal-Domínguez

2013-09-02T23:59:59.000Z

225

Adiabatic Quantum Programming: Minor Embedding With Hard Faults  

SciTech Connect

Adiabatic quantum programming defines the time-dependent mapping of a quantum algorithm into the hardware or logical fabric. An essential programming step is the embedding of problem-specific information into the logical fabric to define the quantum computational transformation. We present algorithms for embedding arbitrary instances of the adiabatic quantum optimization algorithm into a square lattice of specialized unit cells. Our methods are shown to be extensible in fabric growth, linear in time, and quadratic in logical footprint. In addition, we provide methods for accommodating hard faults in the logical fabric without invoking approximations to the original problem. These hard fault-tolerant embedding algorithms are expected to prove useful for benchmarking the adiabatic quantum optimization algorithm on existing quantum logical hardware. We illustrate this versatility through numerical studies of embeddabilty versus hard fault rates in square lattices of complete bipartite unit cells.

Klymko, Christine F [ORNL] [ORNL; Sullivan, Blair D [ORNL] [ORNL; Humble, Travis S [ORNL] [ORNL

2013-01-01T23:59:59.000Z

226

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

227

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

228

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

229

What is a quantum computer, and how do we build one?  

E-Print Network (OSTI)

The DiVincenzo criteria for implementing a quantum computer have been seminal in focussing both experimental and theoretical research in quantum information processing. These criteria were formulated specifically for the circuit model of quantum computing. However, several new models for quantum computing (paradigms) have been proposed that do not seem to fit the criteria well. The question is therefore what are the general criteria for implementing quantum computers. To this end, a formal operational definition of a quantum computer is introduced. It is then shown that according to this definition a device is a quantum computer if it obeys the following four criteria: Any quantum computer must (1) have a quantum memory; (2) facilitate a controlled quantum evolution of the quantum memory; (3) include a method for cooling the quantum memory; and (4) provide a readout mechanism for subsets of the quantum memory. The criteria are met when the device is scalable and operates fault-tolerantly. We discuss various existing quantum computing paradigms, and how they fit within this framework. Finally, we lay out a roadmap for selecting an avenue towards building a quantum computer. This is summarized in a decision tree intended to help experimentalists determine the most natural paradigm given a particular physical implementation.

Carlos A. Perez-Delgado; Pieter Kok

2009-06-24T23:59:59.000Z

230

Resources required for topological quantum factoring  

Science Conference Proceedings (OSTI)

We consider a hypothetical topological quantum computer composed of either Ising or Fibonacci anyons. For each case, we calculate the time and number of qubits (space) necessary to execute the most computationally expensive step of Shor's algorithm, modular exponentiation. For Ising anyons, we apply Bravyi's distillation method [S. Bravyi, Phys. Rev. A 73, 042313 (2006)] which combines topological and nontopological operations to allow for universal quantum computation. With reasonable restrictions on the physical parameters we find that factoring a 128-bit number requires approximately 10{sup 3} Fibonacci anyons versus at least 3x10{sup 9} Ising anyons. Other distillation algorithms could reduce the resources for Ising anyons substantially.

Baraban, M. [Department of Physics, Yale University, 217 Prospect Street, New Haven, Connecticut 06511 (United States); Bonesteel, N. E. [Department of Physics and National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310 (United States); Simon, S. H. [Rudolf Peierls Centre for Theoretical Physics, Oxford University, 1 Keble Road, Oxford OX1 3NP (United Kingdom)

2010-06-15T23:59:59.000Z

231

Number fluctuations of cold, spatially split bosonic objects  

Science Conference Proceedings (OSTI)

We investigate the number fluctuations of spatially split many-boson systems employing a theorem about the maximally and minimally attainable variances of an observable. The number fluctuations of many-boson systems are given for different numbers of lattice sites and both mean-field and many-body wave functions. It is shown which states maximize the particle number fluctuations, both in lattices and double wells. The fragmentation of the states is discussed, and it is shown that the number fluctuations of some fragmented states are identical to those of fully condensed states.

Sakmann, Kaspar; Streltsov, Alexej I.; Cederbaum, Lorenz S. [Theoretische Chemie, Physikalisch-Chemisches Institut, Universitaet Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg (Germany); Alon, Ofir E. [Department of Physics, University of Haifa at Oranim, Tivon 36006 (Israel)

2011-11-15T23:59:59.000Z

232

Quantum Gravitational Uncertainty of Transverse Position  

E-Print Network (OSTI)

It is argued that holographic bounds on the information content of spacetime might be directly measurable. A new holographic uncertainty principle is conjectured as a quantum property of nearly flat spacetime: The spatial wavefunction of a body at rest at position L relative to any observer has a width in directions transverse to L greater than Delta x_H=C(Ll_P)^{1/2}, where l_p denotes the Planck length and C is of the order of unity. It is shown that this angular uncertainty Delta theta > C (l_P/L)^{1/2} corresponds to the information loss and nonlocality that occur if 3D space has a holographic dual description in terms of Planck-scale waves on a 2D screen with encoding close to the diffraction limit, and agrees with covariant holographic entropy bounds on total number of degrees of freedom. It is estimated that this effect can be precisely tested by interferometers capable of transverse position measurements, such as the Laser Interferometer Space Antenna.

Hogan, Craig J

2007-01-01T23:59:59.000Z

233

QUANTUM CONVERSION IN PHOTOSYNTHESIS  

E-Print Network (OSTI)

W _7405-eng- 4B QUANTUM CONVERSION IN PHOTOSYNTHESIS Melvint r UCRL-9 533 QUANrUM CONVERSION IN PHWOSYNTHESIS * Melvinitself. The primary quantum conversion act is an ionization

Calvin, Melvin

2008-01-01T23:59:59.000Z

234

Instrumentation for quantum computers  

E-Print Network (OSTI)

Quantum computation poses challenging engineering and basic physics issues for the control of nanoscale systems. In particular, experimental realizations of up to seven-qubit NMR quantum computers have acutely illustrated ...

Huang, Wei-Han, 1979-

2004-01-01T23:59:59.000Z

235

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

236

Searching with Quantum Computers  

E-Print Network (OSTI)

This article introduces quantum computation by analogy with probabilistic computation. A basic description of the quantum search algorithm is given by representing the algorithm as a C program in a novel way.

Lov K. Grover

2000-11-30T23:59:59.000Z

237

Construction Project Number  

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

North Execution - (2009 - 2011) North Execution - (2009 - 2011) Construction Project Number 2009 2010 2011 Project Description ANMLPL 0001C 76,675.32 - - Animas-Laplata circuit breaker and power rights CRGRFL 0001C - - 7,177.09 Craig Rifle Bay and transfer bay upgrade to 2000 amps; / Convert CRG RFL to 345 kV out of Bears Ear Sub FGE 0019C - - 39,207.86 Replace 69/25kV transformer KX2A at Flaming Gorge FGE 0020C - - 52,097.12 Flaming Gorge: Replace failed KW2A transformer HDN 0069C 16,638.52 208,893.46 3,704,578.33 Replace failed transformer with KZ1A 250 MVA 230/138kv

238

KPA Activity Number  

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

supports CMM-SW Level 2 supports CMM-SW Level 2 Mapping of the DOE Systems Engineering Methodology to the Software Engineering Institute (SEI) Software Capability Maturity Model (CMM- SW) level 2. Date: September 2002 Page 1 KPA Activity Number KPA Activity SEM Section SME Work Product SQSE Web Site http://cio.doe.gov/sqse REQUIREMENTS MANAGEMENT RM-1 The software engineering group reviews the allocated requirements before they are incorporated in the software project. Chapter 3.0 * Develop High-Level Project Requirements Chapter 4.0 * Establish Functional Baseline * Project Plan * Requirements Specification Document * Requirements Management awareness * Defining Project Requirements RM-2 The software engineering group uses the allocated requirements as the basis for

239

A Graphic Representation of States for Quantum Copying Machines  

E-Print Network (OSTI)

The aim of this paper is to introduce a new graphic representation of quantum states by means of a specific application: the analysis of two models of quantum copying machines. The graphic representation by diagrams of states offers a clear and detailed visualization of quantum information's flow during the unitary evolution of not too complex systems. The diagrams of states are exponentially more complex in respect to the standard representation and this clearly illustrates the discrepancy of computational power between quantum and classical systems. After a brief introductive exposure of the general theory, we present a constructive procedure to illustrate the new representation by means of concrete examples. Elementary diagrams of states for single-qubit and two-qubit systems and a simple scheme to represent entangled states are presented. Quantum copying machines as imperfect cloners of quantum states are introduced and the quantum copying machines of Griffiths and Niu and of Buzek and Hillery are analyzed, determining quantum circuits of easier interpretation. The method has indeed shown itself to be extremely successful for the representation of the involved quantum operations and it has allowed to point out the characteristic aspects of the quantum computations examined.

Sara Felloni; Giuliano Strini

2006-09-29T23:59:59.000Z

240

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

Note: This page contains sample records for the topic "quantum numbers shown" from the National Library of EnergyBeta (NLEBeta).
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241

Quantum discord as a resource in quantum protocols  

E-Print Network (OSTI)

We show quantum discord to be a resource in quantum information processing. This is accomplished by proving a relation between quantum discord and the yield of the quantum protocols. Our results are derived by studying the fully quantum Slepian-Wolf protocol -- a unification of all bipartite, unidirectional and memoryless quantum communication protocols -- in the presence of noise. As examples, we elucidate the significance of quantum discord in quantum teleportation, superdense coding, and entanglement distillation. Finally, we provide the first quantitative relation between quantum discord and the query complexity of quantum computations.

Madhok, Vaibhav

2012-01-01T23:59:59.000Z

242

Quantum repeaters and quantum key distribution: the impact of entanglement distillation on the secret key rate  

E-Print Network (OSTI)

We investigate quantum repeaters in the context of quantum key distribution. We optimize the secret key rate per memory per second with respect to different distillation protocols and distillation strategies. For this purpose, we also derive an analytical expression for the average number of entangled pairs created by the quantum repeater, including classical communication times for entanglement swapping and entanglement distillation. We investigate the impact of this classical communication time on the secret key rate. We finally study the effect of the detector efficiency on the secret key rate.

Sylvia Bratzik; Silvestre Abruzzo; Hermann Kampermann; Dagmar Bruß

2013-03-14T23:59:59.000Z

243

Quantum money from knots  

E-Print Network (OSTI)

Quantum money is a cryptographic protocol in which a mint can produce a quantum state, no one else can copy the state, and anyone (with a quantum computer) can verify that the state came from the mint. We present a concrete quantum money scheme based on superpositions of diagrams that encode oriented links with the same Alexander polynomial. We expect our scheme to be secure against computationally bounded adversaries.

Farhi, Edward; Hassidim, Avinatan; Lutomirski, Andrew; Shor, Peter

2010-01-01T23:59:59.000Z

244

Quantum money from knots  

E-Print Network (OSTI)

Quantum money is a cryptographic protocol in which a mint can produce a quantum state, no one else can copy the state, and anyone (with a quantum computer) can verify that the state came from the mint. We present a concrete quantum money scheme based on superpositions of diagrams that encode oriented links with the same Alexander polynomial. We expect our scheme to be secure against computationally bounded adversaries.

Edward Farhi; David Gosset; Avinatan Hassidim; Andrew Lutomirski; Peter Shor

2010-04-28T23:59:59.000Z

245

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

246

Testing quantum mechanics  

E-Print Network (OSTI)

As experiments continue to push the quantum-classical boundary to include increasingly complex dynamical systems, the interpretation of experimental data becomes more and more challenging: when the observations are noisy, indirect, and limited, how can we be sure that we are observing quantum behavior? This tutorial highlights some of the difficulties in such experimental tests of quantum mechanics, using optomechanics as the central example, and discusses how the issues can be resolved using techniques from statistics and insights from quantum information theory.

Mankei Tsang

2013-06-12T23:59:59.000Z

247

Quantum Algorithm Zoo  

Science Conference Proceedings (OSTI)

... 27 Andrew M. Childs, Richard Cleve, Stephen P. Jordan, and David Yeung Discrete-query quantum algorithm for NAND trees. ...

2013-11-11T23:59:59.000Z

248

Quantum Physics Portal  

Science Conference Proceedings (OSTI)

... for Science and Technology (CODATA) issues recommended values of the fundamental physical constants ... see all Quantum Physics programs and ...

2013-03-07T23:59:59.000Z

249

Quantum Physics Division Homepage  

Science Conference Proceedings (OSTI)

... Contact. Physical Measurement Laboratory Quantum Physics Division General Information: 303-735-1985 Telephone 303-492-5235 Facsimile. ...

2013-06-28T23:59:59.000Z

250

Quantum Physics Theory  

Science Conference Proceedings (OSTI)

Quantum Physics Theory. Summary: Theoretical work ... constant. The database is available at http://physics.nist.gov/hdel. Precise ...

2010-10-05T23:59:59.000Z

251

Vacuum energy: quantum hydrodynamics vs quantum gravity  

E-Print Network (OSTI)

We compare quantum hydrodynamics and quantum gravity. They share many common features. In particular, both have quadratic divergences, and both lead to the problem of the vacuum energy, which in the quantum gravity transforms to the cosmological constant problem. We show that in quantum liquids the vacuum energy density is not determined by the quantum zero-point energy of the phonon modes. The energy density of the vacuum is much smaller and is determined by the classical macroscopic parameters of the liquid including the radius of the liquid droplet. In the same manner the cosmological constant is not determined by the zero-point energy of quantum fields. It is much smaller and is determined by the classical macroscopic parameters of the Universe dynamics: the Hubble radius, the Newton constant and the energy density of matter. The same may hold for the Higgs mass problem: the quadratically divergent quantum correction to the Higgs potential mass term is also cancelled by the microscopic (trans-Planckian) degrees of freedom due to thermodynamic stability of the whole quantum vacuum.

G. E. Volovik

2005-05-20T23:59:59.000Z

252

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

253

Stephen Hawking Quantum Gravity  

E-Print Network (OSTI)

Stephen Hawking and Quantum Gravity Matt Visser Physics Department Washington University Saint Louis USA Science Saturdays 4 Nov 2000 #12; Stephen Hawking and Quantum Gravity Abstract: Through research, Stephen Hawking has captured a place in the popular imagina- tion. Quantum gravity in its various

Visser, Matt

254

Quantum money from knots  

E-Print Network (OSTI)

Quantum money is a cryptographic protocol in which a mint can produce a quantum state, no one else can copy the state, and anyone (with a quantum computer) can verify that the state came from the mint. We present a concrete ...

Farhi, Edward

255

Quantum Computing Computer Scientists  

E-Print Network (OSTI)

Quantum Computing for Computer Scientists Noson S. Yanofsky and Mirco A. Mannucci #12;© May 2007 Noson S. Yanofsky Mirco A. Mannucci #12;Quantum Computing for Computer Scientists Noson S. Yanofsky of Vector Spaces 3 The Leap From Classical to Quantum 3.1 Classical Deterministic Systems 3.2 Classical

Yanofsky, Noson S.

256

Topological Quantum Distillation  

E-Print Network (OSTI)

We construct a class of topological quantum codes to perform quantum entanglement distillation. These codes implement the whole Clifford group of unitary operations in a fully topological manner and without selective addressing of qubits. This allows us to extend their application also to quantum teleportation, dense coding and computation with magic states.

H. Bombin; M. A. Martin-Delgado

2006-05-16T23:59:59.000Z

257

Control Landscapes for Observable Preparation with Open Quantum Systems  

E-Print Network (OSTI)

A quantum control landscape is defined as the observable as a function(al) of the system control variables. Such landscapes were introduced to provide a basis to understand the increasing number of successful experiments controlling quantum dynamics phenomena. This paper extends the concept to encompass the broader context of the environment having an influence. For the case that the open system dynamics are fully controllable, it is shown that the control landscape for open systems can be lifted to the analysis of an equivalent auxiliary landscape of a closed composite system that contains the environmental interactions. This inherent connection can be analyzed to provide relevant information about the topology of the original open system landscape. Application to the optimization of an observable expectation value reveals the same landscape simplicity observed in former studies on closed systems. In particular, no false sub-optimal traps exist in the system control landscape when seeking to optimize an observable, even in the presence of complex environments. Moreover, a quantitative study of the control landscape of a system interacting with a thermal environment shows that the enhanced controllability attainable with open dynamics significantly broadens the range of the achievable observable values over the control landscape.

Rebing Wu; Alexander Pechen; Herschel Rabitz; Michael Hsieh; Benjamin Tsou

2007-08-16T23:59:59.000Z

258

The use of bulk states to accelerate the band edge state calculation of a semiconductor quantum dot  

E-Print Network (OSTI)

conduction band. For large CdSe quantum dots, the number ofidate our approach on both CdSe bulk systems and colloidala physical point of view, CdSe quantum dots are one of the

Vomel, Christof; Tomov, Stanimire Z.; Wang, Lin-Wang; Marques, Osni A.; Dongarra, Jack J.

2008-01-01T23:59:59.000Z

259

The Propagation of Quantum Information Through a Spin System  

E-Print Network (OSTI)

It has been recently suggested that the dynamics of a quantum spin system may provide a natural mechanism for transporting quantum information. We show that one dimensional rings of qubits with fixed (time-independent) interactions, constant around the ring, allow high fidelity communication of quantum states. We show that the problem of maximising the fidelity of the quantum communication is related to a classical problem in fourier wave analysis. By making use of this observation we find that if both communicating parties have access to limited numbers of qubits in the ring (a fraction that vanishes in the limit of large rings) it is possible to make the communication arbitrarily good.

Tobias J. Osborne; Noah Linden

2003-12-16T23:59:59.000Z

260

MASSIVE QUANTUM MEMORIES BY PERIODICALLY INVERTED DYNAMIC EVOLUTIONS  

E-Print Network (OSTI)

We introduce a general scheme to realize perfect quantum state reconstruction and storage in systems of interacting qubits. This novel approach is based on the idea of controlling the residual interactions by suitable external controls that, acting on the inter-qubit couplings, yield time-periodic inversions in the dynamical evolution, thus cancelling exactly the effects of quantum state diffusion. We illustrate the method for spin systems on closed rings with XY residual interactions, showing that it enables the massive storage of arbitrarily large numbers of local states, and we demonstrate its robustness against several realistic sources of noise and imperfections. Keywords: Quantum Information; Quantum Control; Spin Systems. 1.

S. M. Giampaolo; F. Illuminati; A. Di Lisi; G. Mazzarella

2005-01-01T23:59:59.000Z

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We encourage you to perform a real-time search of NLEBeta
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261

Efficient classical simulation of the approximate quantum Fourier transform  

E-Print Network (OSTI)

We present a method for classically simulating quantum circuits based on the tensor contraction model of Markov and Shi (quant-ph/0511069). Using this method we are able to classically simulate the approximate quantum Fourier transform in polynomial time. Moreover, our approach allows us to formulate a condition for the composability of simulable quantum circuits. We use this condition to show that any circuit composed of a constant number of approximate quantum Fourier transform circuits and log-depth circuits with limited interaction range can also be efficiently simulated.

Nadav Yoran; Anthony J. Short

2006-11-23T23:59:59.000Z

262

Utah Natural Gas Number of Commercial Consumers (Number of Elements...  

Gasoline and Diesel Fuel Update (EIA)

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263

Utah Natural Gas Number of Industrial Consumers (Number of Elements...  

U.S. Energy Information Administration (EIA) Indexed Site

Industrial Consumers (Number of Elements) Utah Natural Gas Number of Industrial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8...

264

Utah Natural Gas Number of Residential Consumers (Number of Elements...  

Annual Energy Outlook 2012 (EIA)

Residential Consumers (Number of Elements) Utah Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

265

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266

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267

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268

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U.S. Energy Information Administration (EIA) Indexed Site

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269

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U.S. Energy Information Administration (EIA) Indexed Site

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270

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U.S. Energy Information Administration (EIA) Indexed Site

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271

Wisconsin Natural Gas Number of Residential Consumers (Number...  

U.S. Energy Information Administration (EIA) Indexed Site

Residential Consumers (Number of Elements) Wisconsin Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

272

Wisconsin Natural Gas Number of Commercial Consumers (Number...  

Annual Energy Outlook 2012 (EIA)

Commercial Consumers (Number of Elements) Wisconsin Natural Gas Number of Commercial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

273

Michigan Natural Gas Number of Residential Consumers (Number...  

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Residential Consumers (Number of Elements) Michigan Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

274

Michigan Natural Gas Number of Industrial Consumers (Number of...  

Annual Energy Outlook 2012 (EIA)

Industrial Consumers (Number of Elements) Michigan Natural Gas Number of Industrial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

275

Idaho Natural Gas Number of Industrial Consumers (Number of Elements...  

Annual Energy Outlook 2012 (EIA)

Industrial Consumers (Number of Elements) Idaho Natural Gas Number of Industrial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

276

Idaho Natural Gas Number of Commercial Consumers (Number of Elements...  

Annual Energy Outlook 2012 (EIA)

Commercial Consumers (Number of Elements) Idaho Natural Gas Number of Commercial Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

277

Idaho Natural Gas Number of Residential Consumers (Number of...  

Annual Energy Outlook 2012 (EIA)

Residential Consumers (Number of Elements) Idaho Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

278

Connecticut Natural Gas Number of Residential Consumers (Number...  

U.S. Energy Information Administration (EIA) Indexed Site

Residential Consumers (Number of Elements) Connecticut Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6...

279

Hawaii Natural Gas Number of Residential Consumers (Number of...  

U.S. Energy Information Administration (EIA) Indexed Site

Residential Consumers (Number of Elements) Hawaii Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

280

Kentucky Natural Gas Number of Residential Consumers (Number...  

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Residential Consumers (Number of Elements) Kentucky Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

Note: This page contains sample records for the topic "quantum numbers shown" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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281

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282

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283

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284

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285

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286

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287

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288

Illinois Natural Gas Number of Residential Consumers (Number...  

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289

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290

Florida Natural Gas Number of Residential Consumers (Number of...  

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Residential Consumers (Number of Elements) Florida Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

291

Iowa Natural Gas Number of Residential Consumers (Number of Elements...  

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Residential Consumers (Number of Elements) Iowa Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

292

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Residential Consumers (Number of Elements) Georgia Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

293

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Residential Consumers (Number of Elements) Arkansas Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7...

294

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295

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296

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297

Mississippi Natural Gas Number of Residential Consumers (Number...  

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298

Arizona Natural Gas Number of Residential Consumers (Number of...  

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299

Pennsylvania Natural Gas Number of Residential Consumers (Number...  

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300

Nebraska Natural Gas Number of Residential Consumers (Number...  

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301

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302

Massachusetts Natural Gas Number of Residential Consumers (Number...  

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303

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304

Vermont Natural Gas Number of Residential Consumers (Number of...  

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305

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308

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309

Colorado Natural Gas Number of Commercial Consumers (Number of...  

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310

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311

New Mexico Natural Gas Number of Industrial Consumers (Number...  

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New Mexico Natural Gas Number of Residential Consumers (Number...  

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314

Texas Natural Gas Number of Commercial Consumers (Number of Elements...  

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315

Texas Natural Gas Number of Residential Consumers (Number of...  

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316

Satellite-Based Quantum Communications  

SciTech Connect

Single-photon quantum communications (QC) offers the attractive feature of 'future proof', forward security rooted in the laws of quantum physics. Ground based quantum key distribution (QKD) experiments in optical fiber have attained transmission ranges in excess of 200km, but for larger distances we proposed a methodology for satellite-based QC. Over the past decade we have devised solutions to the technical challenges to satellite-to-ground QC, and we now have a clear concept for how space-based QC could be performed and potentially utilized within a trusted QKD network architecture. Functioning as a trusted QKD node, a QC satellite ('QC-sat') could deliver secret keys to the key stores of ground-based trusted QKD network nodes, to each of which multiple users are connected by optical fiber or free-space QC. A QC-sat could thereby extend quantum-secured connectivity to geographically disjoint domains, separated by continental or inter-continental distances. In this paper we describe our system concept that makes QC feasible with low-earth orbit (LEO) QC-sats (200-km-2,000-km altitude orbits), and the results of link modeling of expected performance. Using the architecture that we have developed, LEO satellite-to-ground QKD will be feasible with secret bit yields of several hundred 256-bit AES keys per contact. With multiple ground sites separated by {approx} 100km, mitigation of cloudiness over any single ground site would be possible, potentially allowing multiple contact opportunities each day. The essential next step is an experimental QC-sat. A number of LEO-platforms would be suitable, ranging from a dedicated, three-axis stabilized small satellite, to a secondary experiment on an imaging satellite. to the ISS. With one or more QC-sats, low-latency quantum-secured communications could then be provided to ground-based users on a global scale. Air-to-ground QC would also be possible.

Hughes, Richard J [Los Alamos National Laboratory; Nordholt, Jane E [Los Alamos National Laboratory; Mc Cabe, Kevin P [Los Alamos National Laboratory; Newell, Raymond T [Los Alamos National Laboratory; Pterson, Charles G [Los Alamos National Laboratory

2010-09-20T23:59:59.000Z

317

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

318

Microscopic quantum structure of black hole and vacuum versus quantum statistical origin of gravity  

E-Print Network (OSTI)

The Planckon densely piled model of vacuum is proposed. Based on it, the microscopic quantum structure of Schwarzschild black hole and quantum statistical origin of its gravity are studied. It is shown that thermodynamic temperature equilibrium and mechanical acceleration balance make the space-time of the black hole horizon singular and Casimir effect works inside the horizon. This effect makes the inside vacuum have less zero fluctuation energy than the outside vacuum, and a temperature difference as well as gravity as thermal pressure are created. A dual relation between inside and outside regions of the black hole is found. By the dual relation, an attractor behaviour of the horizon surface is unveiled. Outside horizon, there exist thermodynamic non-equilibrium and mechanical non-balance which lead to outward centrifugal energy flow and inward gravitation energy flow, their compensation establishes local equilibrium. The lost vacuum energy in negative gravitation potential regions has been removed to the black hole surface to form a spherical Planckon shell with the thickness of Planckon diameter. All the particles absorbed by the black hole have fallen down to the horizon and converted into spin 1/2 radiation quanta made of standing waves on the horizon sphere with the mean energy related to Hawking-Unruh temperature, thermodynamic equilibrium and mechanical balance keep them stable and be tightly bound in the horizon. The gravitation mass 2M and physical mass $M$ of the black hole are calculated. The entropy of the black hole, calculated from the microscopic state number of the many-body system of radiation fermion quanta, is well consistent with Hawking. A radical modification of the temperature law of the black hole is made. The accelerating expansion of the universe yields the expansion cosmon and its energy density agrees with dark energy density.

Shun-Jin Wang

2012-12-24T23:59:59.000Z

319

Quantum Information Science | ornl.gov  

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

Engineering Analysis Behavioral Sciences Geographic Information Science and Technology Quantum Information Science Quantum Communication and Security Quantum-Enhanced Sensing...

320

High freestream turbulence levels have been shown to greatly augment the heat transfer along a gas turbine airfoil, particularly for the first stage  

E-Print Network (OSTI)

along a gas turbine airfoil, particularly for the first stage nozzle guide vane. For this study of the variables affecting boundary layer development on gas turbine airfoils, studies need to be performed of a variety of gas turbine combustors have shown that the levels can range between 8% and 40% (Kuotmos and Mc

Thole, Karen A.

Note: This page contains sample records for the topic "quantum numbers shown" from the National Library of EnergyBeta (NLEBeta).
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321

Causal signal transmission by quantum fields. II. Quantum-statistical response of interacting bosons  

E-Print Network (OSTI)

We analyse nonperturbatively signal transmission patterns in Green's functions of interacting quantum fields. Quantum field theory is re-formulated in terms of the nonlinear quantum-statistical response of the field. This formulation applies equally to interacting relativistic fields and nonrelativistic models. Of crucial importance is that all causality properties to be expected of a response formulation indeed hold. Being by construction equivalent to Schwinger's closed-time-loop formalism, this formulation is also shown to be related naturally to both Kubo's linear response and Glauber's macroscopic photodetection theories, being a unification of the two with generalisation to the nonlinear quantum-statistical response problem. In this paper we introduce response formulation of bosons; response reformulation of fermions will be subject of a separate paper.

L. I. Plimak; S. Stenholm

2008-04-25T23:59:59.000Z

322

Integral Transforms in Relativistic Quantum Constraint Mechanics  

E-Print Network (OSTI)

In relativistic quantum constraint mechanics the state of a physical system is constrained to a 3-dimensional subspace of Minkowski 4-space. Fourier transformation can be used to relate this state between constraint spaces in 4-position and 4-momentum space. It is shown that integral transforms of this nature can be carried out using Lorentz-invariant 3-dimensional constraint space coordinates such that a complete equivalence class of 4-space representations can be constructed from the transform. This method is further applied to develop a relativistic generalization of the Segal-Bargmann transformation that leads to the representation of quantum systems in a three-dimensional subspace of Bargmann 4-space.

Robert J. Ducharme

2011-01-29T23:59:59.000Z

323

Quantum Capacities of Channels with small Environment  

E-Print Network (OSTI)

We investigate the quantum capacity of noisy quantum channels which can be represented by coupling a system to an effectively small environment. A capacity formula is derived for all cases where both system and environment are two-dimensional--including all extremal qubit channels. Similarly, for channels acting on higher dimensional systems we show that the capacity can be determined if the channel arises from a sufficiently small coupling to a qubit environment. Extensions to instances of channels with larger environment are provided and it is shown that bounds on the capacity with unconstrained environment can be obtained from decompositions into channels with small environment.

Michael M. Wolf; David Perez-Garcia

2006-07-11T23:59:59.000Z

324

Kicked rotor quantum resonances in position space  

E-Print Network (OSTI)

We present an approach of the kicked rotor quantum resonances in position-space, based on its analogy with the optical Talbot effect. This approach leads to a very simple picture of the physical mechanism underlying the dynamics and to analytical expressions for relevant physical quantities, such as mean momentum or kinetic energy. The ballistic behavior, which is closely associated to quantum resonances, is analyzed and shown to emerge from a coherent adding of successive kicks applied to the rotor thanks to a periodic reconstruction of the spatial wavepacket.

Maxence Lepers; Véronique Zehnlé; Jean Claude Garreau

2007-11-11T23:59:59.000Z

325

Kicked rotor quantum resonances in position space  

E-Print Network (OSTI)

We present an approach of the kicked rotor quantum resonances in position-space, based on its analogy with the optical Talbot effect. This approach leads to a very simple picture of the physical mechanism underlying the dynamics and to analytical expressions for relevant physical quantities, such as mean momentum or kinetic energy. The ballistic behavior, which is closely associated to quantum resonances, is analyzed and shown to emerge from a coherent adding of successive kicks applied to the rotor thanks to a periodic reconstruction of the spatial wavepacket.

Lepers, Maxence; Garreau, Jean Claude

2007-01-01T23:59:59.000Z

326

Quantum-Classical Correspondence in Nonrelativistic Electrodynamics  

SciTech Connect

A form of classical electrodynamic field exists which gives exact agreement with the operator field of quantum electrodynamics (QED) for the Lamb shift of a harmonically bound point electron. Here it is pointed out that this form of classical theory with its physically acceptable interpretation is the result of an unconventional resolution of a mathematically ambiguous term in classical field theory. Finally a quantum-classical correspondence principle is shown to exist in the sense that the classical field and expectation value of the QED operator field are identical if retardation is neglected in the latter.

Ritchie, A.B.; Weatherford, C.A.

1999-10-14T23:59:59.000Z

327

Quantum classical correspondence in nonrelativistic electrodynamics  

SciTech Connect

A form of classical electrodynamic field exists which gives exact agreement with the operator field of quantum electrodynamics (QED) for the Lamb shift of a harmonically bound point electron. Here it is pointed out that this form of classical theory, with its physically acceptable interpretation, is the result of an unconventional resolution of a mathematically ambiguous term in classical field theory. Finally, a quantum classical correspondence principle is shown to exist in the sense that the classical field and expectation value of the QED operator field are identical, if retardation is neglected in the latter.

Ritchie, B.; Weatherford, C.A.

1999-12-01T23:59:59.000Z

328

Biased nonlocal quantum games  

E-Print Network (OSTI)

We address the question of when quantum entanglement is a useful resource for information processing tasks by presenting a new class of nonlocal games that are simple, direct, generalizations of the Clauser Horne Shimony Holt game. For some ranges of the parameters that specify the games, quantum mechanics offers an advantage, while, surprisingly, for others quantum mechanics is no more powerful than classical mechanics in performing the nonlocal task. This sheds new light on the difference between classical, quantum and super-quantum correlations.

Thomas Lawson; Noah Linden; Sandu Popescu

2010-11-29T23:59:59.000Z

329

Quantum Operation Time Reversal  

E-Print Network (OSTI)

The dynamics of an open quantum system can be described by a quantum operation, a linear, complete positive map of operators. Here, I exhibit a compact expression for the time reversal of a quantum operation, which is closely analogous to the time reversal of a classical Markov transition matrix. Since open quantum dynamics are stochastic, and not, in general, deterministic, the time reversal is not, in general, an inversion of the dynamics. Rather, the system relaxes towards equilibrium in both the forward and reverse time directions. The probability of a quantum trajectory and the conjugate, time reversed trajectory are related by the heat exchanged with the environment.

Crooks, Gavin E

2007-01-01T23:59:59.000Z

330

Quantum Operation Time Reversal  

E-Print Network (OSTI)

The dynamics of an open quantum system can be described by a quantum operation, a linear, complete positive map of operators. Here, I exhibit a compact expression for the time reversal of a quantum operation, which is closely analogous to the time reversal of a classical Markov transition matrix. Since open quantum dynamics are stochastic, and not, in general, deterministic, the time reversal is not, in general, an inversion of the dynamics. Rather, the system relaxes towards equilibrium in both the forward and reverse time directions. The probability of a quantum trajectory and the conjugate, time reversed trajectory are related by the heat exchanged with the environment.

Gavin E. Crooks

2007-06-26T23:59:59.000Z

331

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

332

'Photosynthetic' Quantum Computers?  

E-Print Network (OSTI)

Do quantum computers already exist in Nature? It is proposed that they do. Photosynthesis is one example in which a 'quantum computer' component may play a role in the 'classical' world of complex biological systems. A 'translation' of the standard metabolic description of the 'front-end' light harvesting complex in photosynthesis into the language of quantum computers is presented. Biological systems represent an untapped resource for thinking about the design and operation of hybrid quantum-classical computers and expanding our current conceptions of what defines a 'quantum computer' in Nature.

Scott M. Hitchcock

2001-08-20T23:59:59.000Z

333

Optimal design and quantum benchmarks for coherent state amplifiers  

E-Print Network (OSTI)

We establish the ultimate quantum limits to the amplification of an unknown coherent state, both in the deterministic and probabilistic case, investigating the realistic scenario where the expected photon number is finite. In addition, we provide the benchmark that experimental realizations have to surpass in order to beat all classical amplification strategies and to demonstrate genuine quantum amplification. Our result guarantees that a successful demonstration is in principle possible for every finite value of the expected photon number.

Giulio Chiribella; Jinyu Xie

2013-01-07T23:59:59.000Z

334

Success Stories: Quantum Dots  

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

Quantum Dots Outshine the Competition for Biomedical Assays Quantum Dots Outshine the Competition for Biomedical Assays Quantum Dots (Qdots), nano-scale semiconductor crystals that emit a range of bright colors when excited by a light source such as a laser, are shining brightly these days. The Berkeley Lab developed technology has been licensed by Quantum Dot Corporation and is being used as fluorescence probes for biomedical assays. The technology just won an R & D 100 Award and Quantum Dot Corporation was named by Fortune magazine as one of 2004's "Cool Companies." Science honored the technology as one of the Top 10 Breakthroughs of the Year in 2003, and Nanotechnology Now named Quantum Dots as the Best Nanotech Product in 2003, among other honors. Quantum Dot Corporation (QDC) is a 1998 start-up biotechnology company

335

Photovoltaic Cell Quantum Efficiency Basics | Department of Energy  

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

Cell Quantum Efficiency Basics Cell Quantum Efficiency Basics Photovoltaic Cell Quantum Efficiency Basics August 20, 2013 - 3:05pm Addthis Quantum efficiency (QE) is the ratio of the number of charge carriers collected by a photovoltaic (PV) cell to the number of photons-or packets of light-of a given energy shining on the solar cell. Quantum efficiency therefore relates to the response of a solar cell to the various wavelengths in the spectrum of light shining on the cell. The QE is given as a function of either wavelength or energy. If all the photons of a certain wavelength are absorbed and the resulting minority carriers (for example, electrons in a p-type material) are collected, then the QE at that particular wavelength has a value of one. The QE for photons with energy below the bandgap is zero.

336

Quantum Discord for Investigating Quantum Correlations without Entanglement in Solids  

E-Print Network (OSTI)

Quantum systems unfold diversified correlations which have no classical counterparts. These quantum correlations have various different facets. Quantum entanglement, as the most well known measure of quantum correlations, plays essential roles in quantum information processing. However, it has recently been pointed out that quantum entanglement cannot describe all the nonclassicality in the correlations. Thus the study of quantum correlations in separable states attracts widely attentions. Herein, we experimentally investigate the quantum correlations of separable thermal states in terms of quantum discord. The sudden change of quantum discord is observed, which captures ambiguously the critical point associated with the behavior of Hamiltonian. Our results display the potential applications of quantum correlations in studying the fundamental properties of quantum system, such as quantum criticality of non-zero temperature.

Rong, Xing; Jin, Fangzhou; Geng, Jianpei; Feng, Pengbo; Xu, Nanyang; Wang, Ya; Ju, Chenyong; Shi, Mingjun; Du, Jiangfeng

2012-01-01T23:59:59.000Z

337

Quantum chaos in the nuclear collective model: I. Classical-quantum correspondence  

E-Print Network (OSTI)

Spectra of the geometric collective model of atomic nuclei are analyzed to identify chaotic correlations among nonrotational states. The model has been previously shown to exhibit a high degree of variability of regular and chaotic classical features with energy and control parameters. Corresponding signatures are now verified also on the quantum level for different schemes of quantization and with a variable classicality constant.

Pavel Stransky; Petr Hruska; Pavel Cejnar

2009-02-23T23:59:59.000Z

338

Thermal Correlation Functions of Twisted Quantum Fields  

E-Print Network (OSTI)

We derive the thermal correlators for twisted quantum fields on noncommutative spacetime. We show that the thermal expectation value of the number operator is same as in commutative spacetime, but that higher correlators are sensitive to the noncommutativity parameters $\\theta^{\\mu\

Basu, Prasad; Vaidya, Sachindeo

2010-01-01T23:59:59.000Z

339

Quantum information and stabilization of quantum states by feedback control  

E-Print Network (OSTI)

Quantum information and stabilization of quantum states by feedback control Hans Maassen September) Karol Zyczkowski (Krakow) #12;Overview #12;Overview 1. Finite quantum systems #12;Overview 1. Finite quantum systems 2. Flow diagrams #12;Overview 1. Finite quantum systems 2. Flow diagrams 3. What

Maassen, Hans

340

Exploring a Full-Sized Black Hole 30 This black ball shown below is the exact size of a black hole with a  

E-Print Network (OSTI)

Exploring a Full-Sized Black Hole 30 This black ball shown below is the exact size of a black hole with a diameter of 9.0 centimeters. Such a black hole would have a mass of 5 times the mass of our Earth. All of this mass would be INSIDE the ball below. Although it looks pretty harmless, if this black hole were at arms

Note: This page contains sample records for the topic "quantum numbers shown" 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

Quantum model of microcavity intersubband electroluminescent devices  

E-Print Network (OSTI)

We present a quantum theoretical analysis of the electroluminescence from an intersubband transition of a quantum well structure embedded in a planar microcavity. By using a cluster factorization method, we have derived a closed set of dynamical equations for the quantum well carrier and cavity photon occupation numbers, the correlation between the cavity field and the intersubband polarization, as well as polarization-polarization contributions. In order to model the electrical excitation, we have considered electron population tunneling from an injector and into an extractor contact. The tunneling rates have been obtained by considering the bare electronic states in the quantum well and the limit of validity of this approximation (broad-band injection) are discussed in detail. We apply the present quantum model to provide a comprehensive description of the electronic transport and optical properties of an intersubband microcavity light emitting diode, accounting for non-radiative carrier relaxation and Pauli blocking. We study the enhancement of the electroluminescence quantum efficiency passing from the weak to the strong polariton coupling regime.

Simone De Liberato; Cristiano Ciuti

2007-11-20T23:59:59.000Z

342

Quantum logarithmic Sobolev inequalities and rapid mixing  

Science Conference Proceedings (OSTI)

A family of logarithmic Sobolev inequalities on finite dimensional quantum state spaces is introduced. The framework of non-commutative L{sub p}-spaces is reviewed and the relationship between quantum logarithmic Sobolev inequalities and the hypercontractivity of quantum semigroups is discussed. This relationship is central for the derivation of lower bounds for the logarithmic Sobolev (LS) constants. Essential results for the family of inequalities are proved, and we show an upper bound to the generalized LS constant in terms of the spectral gap of the generator of the semigroup. These inequalities provide a framework for the derivation of improved bounds on the convergence time of quantum dynamical semigroups, when the LS constant and the spectral gap are of the same order. Convergence bounds on finite dimensional state spaces are particularly relevant for the field of quantum information theory. We provide a number of examples, where improved bounds on the mixing time of several semigroups are obtained, including the depolarizing semigroup and quantum expanders.

Kastoryano, Michael J. [Dahlem Center for Complex Quantum Systems, Freie Universitaet Berlin, 14195 Berlin (Germany)] [Dahlem Center for Complex Quantum Systems, Freie Universitaet Berlin, 14195 Berlin (Germany); Temme, Kristan [Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)] [Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2013-05-15T23:59:59.000Z

343

Spectrum of electron-hole states of the Si/Ge structure with Ge quantum dots  

Science Conference Proceedings (OSTI)

The lateral photoconductivity spectra of Si/Ge multilayer structures with Ge quantum dots of various sizes are investigated. We observed optical transition lines between the hole levels of quantum dots and electronic states of Si. This enabled us to construct a detailed energy level diagram of the electron-hole spectrum of the Si/Ge structures. It is shown that the hole levels of Ge quantum dots are successfully described by the 'quantum box' model using the actual sizes of Ge islands. It I found that the position of the longwavelength photosensitivity boundary of Si/Ge structures with Ge quantum dots can be controlled by changing the growth parameters.

Talochkin, A. B., E-mail: tal@thermo.isp.nsc.ru; Chistokhin, I. B., E-mail: igor@thermo.isp.nsc.ru [Russian Academy of Sciences, Institute of Semiconductor Physics, Siberian Branch (Russian Federation)

2011-09-15T23:59:59.000Z

344

Photoconductivity of Si/Ge multilayer structures with Ge quantum dots pseudomorphic to the Si matrix  

SciTech Connect

Longitudinal photoconductivity spectra of Si/Ge multilayer structures with Ge quantum dots grown pseudomorphically to the Si matrix are studied. Lines of optical transitions between hole levels of quantum dots and Si electronic states are observed. This allowed us to construct a detailed energy-level diagram of electron-hole levels of the structure. It is shown that hole levels of pseudomorphic Ge quantum dots are well described by the simplest 'quantum box' model using actual sizes of Ge islands. The possibility of controlling the position of the long-wavelength photosensitivity edge by varying the growth parameters of Si/Ge structures with Ge quantum dots is determined.

Talochkin, A. B., E-mail: tal@thermo.isp.nsc.ru; Chistokhin, I. B. [Russian Academy of Sciences, Rzhanov Institute of Semiconductor Physics, Siberian Branch (Russian Federation)

2011-07-15T23:59:59.000Z

345

Quantum Fine-Grained Entropy  

E-Print Network (OSTI)

Regarding the strange properties of quantum entropy and entanglement, e.g., the negative quantum conditional entropy, we revisited the foundations of quantum entropy, namely, von Neumann entropy, and raised the new method of quantum fine-grained entropy. With the applications in entanglement theory, quantum information processing, and quantum thermodynamics, we demonstrated the capability of quantum fine-grained entropy to resolve some notable confusions and problems, including the measure of entanglement and quantumness, the additivity conjecture of entanglement of formation etc, and the definition of temperature for single quantum system.

Wang, Dong-Sheng

2012-01-01T23:59:59.000Z

346

Spin Chains as Perfect Quantum State Mirrors  

E-Print Network (OSTI)

Quantum information transfer is an important part of quantum information processing. Several proposals for quantum information transfer along linear arrays of nearest-neighbor coupled qubits or spins were made recently. Perfect transfer was shown to exist in two models with specifically designed strongly inhomogeneous couplings. We show that perfect transfer occurs in an entire class of chains, including systems whose nearest-neighbor couplings vary only weakly along the chain. The key to these observations is the Jordan-Wigner mapping of spins to noninteracting lattice fermions which display perfectly periodic dynamics if the single-particle energy spectrum is appropriate. After a half-period of that dynamics any state is transformed into its mirror image with respect to the center of the chain. The absence of fermion interactions preserves these features at arbitrary temperature and allows for the transfer of nontrivially entangled states of several spins or qubits.

Peter Karbach; Joachim Stolze

2005-01-03T23:59:59.000Z

347

Radiation reaction in nonrelativistic quantum theory. [Review  

SciTech Connect

Some recent work is reviewed on the quantum theory of radiation reaction. The starting point is the Heisenberg operator equation of motion for a nonrelativistic point electron coupled to the quantized electromagnetic field. It is shown that this equation, in contrast to its classical counterpart, leads to a finite value for the electrostatic self-energy of a point electron and, for values of the fine structure constant ..cap alpha.. approximately less than 1, admits neither runaway behavior nor noncausal motion. Furthermore, the correspondence limit of the solution to the quantum mechanical equation of motion agrees with that of the Lorentz--Dirac theory in the classical regime, but without the imposition of additional conditions and with no possibility of observable noncausality. Thus, a consistent picture of a classical point electron emerges in the correspondence limit of the quantum mechanical theory. 17 references.

Sharp, D.H.

1979-01-01T23:59:59.000Z

348

Quantum process tomography with coherent states  

E-Print Network (OSTI)

We develop an enhanced technique for characterizing quantum optical processes based on probing unknown quantum processes only with coherent states. Our method substantially improves the original proposal [M. Lobino et al., Science 322, 563 (2008)], which uses a filtered Glauber-Sudarshan decomposition to determine the effect of the process on an arbitrary state. We introduce a new relation between the action of a general quantum process on coherent state inputs and its action on an arbitrary quantum state. This relation eliminates the need to invoke the Glauber-Sudarshan representation for states; hence it dramatically simplifies the task of process identification and removes a potential source of error. The new relation also enables straightforward extensions of the method to multi-mode and non-trace-preserving processes. We illustrate our formalism with several examples, in which we derive analytic representations of several fundamental quantum optical processes in the Fock basis. In particular, we introduce photon-number cutoff as a reasonable physical resource limitation and address resource vs accuracy trade-off in practical applications. We show that the accuracy of process estimation scales inversely with the square root of photon-number cutoff.

Saleh Rahimi-Keshari; Artur Scherer; Ady Mann; Ali T. Rezakhani; A. I. Lvovsky; Barry C. Sanders

2010-09-17T23:59:59.000Z

349

Fidelity criterion for quantum-domain transmission and storage of coherent states beyond unit-gain constraint  

E-Print Network (OSTI)

We generalize the experimental success criterion for quantum teleportation/memory in continuous-variable quantum systems to be suitable for non-unit-gain condition by considering attenuation/amplification of the coherent-state amplitude. The new criterion can be used for a non-ideal quantum memory and long distance quantum communication as well as quantum devices with amplification process. It is also shown that the framework to measure the average fidelity is capable of detecting all Gaussian channels in quantum domain.

Ryo Namiki; Masato Koashi; Nobuyuki Imoto

2007-03-17T23:59:59.000Z

350

Generalized quantum defect methods in quantum chemistry  

E-Print Network (OSTI)

The reaction matrix of multichannel quantum defect theory, K, gives a complete picture of the electronic structure and the electron - nuclear dynamics for a molecule. The reaction matrix can be used to examine both bound ...

Altunata, Serhan

2006-01-01T23:59:59.000Z

351

Quantum transfer operators and quantum scattering  

E-Print Network (OSTI)

These notes describe a new method to investigate the spectral properties if quantum scattering Hamiltonians, developed in collaboration with J. Sj\\"ostrand and M.Zworski. This method consists in constructing a family of "quantized transfer operators" $\\{M(z,h)\\}$ associated with a classical Poincar\\'e section near some fixed classical energy E. These operators are finite dimensional, and have the structure of "open quantum maps". In the semiclassical limit, the family $\\{M(z,h)\\}$ encode the quantum dynamics near the energy E. In particular, the quantum resonances of the form $E+z$, for $z=O(h)$, are obtained as the roots of $\\det(1-M(z,h))=0$.

Stéphane Nonnenmacher

2010-01-22T23:59:59.000Z

352

Quantum Copy-Protection and Quantum Money  

E-Print Network (OSTI)

Forty years ago, Wiesner proposed using quantum states to create money that is physically impossible to counterfeit, something that cannot be done in the classical world. However, Wiesner's scheme required a central bank ...

Aaronson, Scott

353

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

354

Quantum Gravity An introductory survey  

E-Print Network (OSTI)

Quantum Gravity An introductory survey Hermann Nicolai Max-Planck-Institut f¨ur Gravitationsphysik (Albert­Einstein­Institut, Potsdam) . ­ p.1/25 #12;Why Quantum Gravity? . ­ p.2/25 #12;Why Quantum Gravity theories: . ­ p.2/25 #12;Why Quantum Gravity? General Relativity and Quantum Theory: not only very

Rossak, Wilhelm R.

355

Quantum Circuit Model Topological Model  

E-Print Network (OSTI)

Quantum Circuit Model Topological Model Comparison of Models Topological Quantum Computation Eric Rowell Texas A&M University October 2010 Eric Rowell Topological Quantum Computation #12;Quantum Circuit Model Topological Model Comparison of Models Outline 1 Quantum Circuit Model Gates, Circuits

Rowell, Eric C.

356

Number: 305 Most Dangerous Vehicles ...  

Science Conference Proceedings (OSTI)

... top> Number: 314 Marine Vegetation Description: Commercial harvesting of marine vegetation such as algae, seaweed and ...

2002-12-12T23:59:59.000Z

357

Quantum Copy-Protection and Quantum Money  

E-Print Network (OSTI)

Forty years ago, Wiesner proposed using quantum states to create money that is physically impossible to counterfeit, something that cannot be done in the classical world. However, Wiesner's scheme required a central bank to verify the money, and the question of whether there can be unclonable quantum money that anyone can verify has remained open since. One can also ask a related question, which seems to be new: can quantum states be used as copy-protected programs, which let the user evaluate some function f, but not create more programs for f? This paper tackles both questions using the arsenal of modern computational complexity. Our main result is that there exist quantum oracles relative to which publicly-verifiable quantum money is possible, and any family of functions that cannot be efficiently learned from its input-output behavior can be quantumly copy-protected. This provides the first formal evidence that these tasks are achievable. The technical core of our result is a "Complexity-Theoretic No-Cloning Theorem," which generalizes both the standard No-Cloning Theorem and the optimality of Grover search, and might be of independent interest. Our security argument also requires explicit constructions of quantum t-designs. Moving beyond the oracle world, we also present an explicit candidate scheme for publicly-verifiable quantum money, based on random stabilizer states; as well as two explicit schemes for copy-protecting the family of point functions. We do not know how to base the security of these schemes on any existing cryptographic assumption. (Note that without an oracle, we can only hope for security under some computational assumption.)

Scott Aaronson

2011-10-24T23:59:59.000Z

358

Quantum Key Distribution Using Quantum Faraday Rotators  

E-Print Network (OSTI)

We propose a new quantum key distribution (QKD) protocol based on the fully quantum mechanical states of the Faraday rotators. The protocol is unconditionally secure against eavesdropping for single-photon source on a noisy environment and robust against impersonation attacks. It also allows for unconditionally secure key distribution for multiphoton source up to two photons. The protocol could be implemented experimentally with the current spintronics technology on semiconductors.

Choi, T; Choi, Mahn-Soo; Choi, Taeseung

2006-01-01T23:59:59.000Z

359

Quantum spins mimic refrigerator magnets - Argonne National Laboratories,  

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

Highlights > Quantum spins mimic refrigerator Highlights > Quantum spins mimic refrigerator magnets Quantum spins mimic refrigerator magnets By Joseph Bernstein * October 11, 2012 The behavior of magnetic moments in metal oxides such as layered iridium is dominated by strong spin-orbit coupling effects. In layered compounds such as Sr3Ir2O7 (shown on the left), the direction of these moments (blue arrows) is controlled at the quantum level by dipolar interactions that are akin to those of classical bar magnets. Another outcome is an unprecedented 'magnon gap' (shown at right), which was measured at the Argonne Advanced Photon Source and reveals that these underlying dipolar magnetic interactions are extremely strong. Current electronic devices depend on manipulating charge. Alternative approaches may rely on not only charge but also the spin of electrons.

360

Quantum Copy-Protection and Quantum Money  

E-Print Network (OSTI)

Forty years ago, Wiesner proposed using quantum states to create money that is physically impossible to counterfeit, something that cannot be done in the classical world. However, Wiesner's scheme required a central bank to verify the money, and the question of whether there can be unclonable quantum money that anyone can verify has remained open since. One can also ask a related question, which seems to be new: can quantum states be used as copy-protected programs, which let the user evaluate some function f, but not create more programs for f? This paper tackles both questions using the arsenal of modern computational complexity. Our main result is that there exist quantum oracles relative to which publicly-verifiable quantum money is possible, and any family of functions that cannot be efficiently learned from its input-output behavior can be quantumly copy-protected. This provides the first formal evidence that these tasks are achievable. The technical core of our result is a "Complexity-Theoretic No-Clon...

Aaronson, Scott

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "quantum numbers shown" 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

Thermodynamics of discrete quantum processes  

E-Print Network (OSTI)

We define thermodynamic configurations and identify two primitives of discrete quantum processes between configurations for which heat and work can be defined in a natural way. This allows us to uncover a general second law for any discrete trajectory that consists of a sequence of these primitives, linking both equilibrium and non-equilibrium configurations. Moreover, in the limit of a discrete trajectory that passes through an infinite number of configurations, i.e. in the reversible limit, we recover the saturation of the second law. Finally, we show that for a discrete Carnot cycle operating between four configurations one recovers Carnot's thermal efficiency.

Janet Anders; Vittorio Giovannetti

2012-11-01T23:59:59.000Z

362

Randomized Benchmarking of Quantum Gates  

E-Print Network (OSTI)

A key requirement for scalable quantum computing is that elementary quantum gates can be implemented with sufficiently low error. One method for determining the error behavior of a gate implementation is to perform process tomography. However, standard process tomography is limited by errors in state preparation, measurement and one-qubit gates. It suffers from inefficient scaling with number of qubits and does not detect adverse error-compounding when gates are composed in long sequences. An additional problem is due to the fact that desirable error probabilities for scalable quantum computing are of the order of 0.0001 or lower. Experimentally proving such low errors is challenging. We describe a randomized benchmarking method that yields estimates of the computationally relevant errors without relying on accurate state preparation and measurement. Since it involves long sequences of randomly chosen gates, it also verifies that error behavior is stable when used in long computations. We implemented randomized benchmarking on trapped atomic ion qubits, establishing a one-qubit error probability per randomized pi/2 pulse of 0.00482(17) in a particular experiment. We expect this error probability to be readily improved with straightforward technical modifications.

E. Knill; D. Leibfried; R. Reichle; J. Britton; R. B. Blakestad; J. D. Jost; C. Langer; R. Ozeri; S. Seidelin; D. J. Wineland

2007-07-06T23:59:59.000Z

363

Quantum frequency conversion of quantum memory compatible photons to telecommunication wavelengths  

E-Print Network (OSTI)

We report an experiment demonstrating quantum frequency conversion of weak light pulses compatible with atomic quantum memories to telecommunication wavelengths. We use a PPLN nonlinear waveguide to convert weak coherent states at the single photon level with a duration of 30ns from a wavelength of 780nm to 1552nm. We measure a maximal waveguide internal (external) conversion efficiency eta_int = 0.41 (eta_ext = 0.25), and we show that the signal to noise ratio (SNR) is good enough to reduce the input photon number below 1. In addition, we show that the noise generated by the pump beam in the crystal is proportional to the spectral bandwidth of the device, suggesting that narrower filtering could significantly increase the SNR. Finally, we demonstrate that the quantum frequency converter can operate in the quantum regime by converting a time-bin qubit and measuring the qubit fidelity after conversion.

Xavier Fernandez-Gonzalvo; Giacomo Corrielli; Boris Albrecht; Marcelli Grimau; Matteo Cristiani; Hugues de Riedmatten

2013-08-05T23:59:59.000Z

364

Nonclassical correlation of cascaded photon pairs emitted from quantum dots  

SciTech Connect

We studied the quantum correlation of the photon pairs generated by biexciton cascade decays of self-assembled quantum dots, and determined the correlation sudden-change temperature, which is shown to be independent of the background noise, far lower than the entanglement sudden-death temperature, and therefore, easier to be observed in experiments. The relationship between the fine-structure splitting and the sudden-change temperature is also provided.

Li, Chuan-Feng; Zou, Yang; Xu, Jin-Shi; Ge, Rong-Chun; Guo, Guang-Can [Key Laboratory of Quantum Information, University of Science and Technology of China, CAS, Hefei 230026 (China)

2011-11-15T23:59:59.000Z

365

Quantum Energy Inequality for the Massive Ising Model  

E-Print Network (OSTI)

A Quantum Energy Inequality (QEI) is derived for the massive Ising model, giving a state-independent lower bound on suitable averages of the energy density; the first QEI to be established for an interacting quantum field theory with nontrivial S-matrix. It is shown that the Ising model has one-particle states with locally negative energy densities, and that the energy density operator is not additive with respect to combination of one-particle states into multi-particle configurations.

Bostelmann, Henning; Fewster, Christopher J

2013-01-01T23:59:59.000Z

366

Motion in Quantum Gravity  

E-Print Network (OSTI)

We tackle the question of motion in Quantum Gravity: what does motion mean at the Planck scale? Although we are still far from a complete answer we consider here a toy model in which the problem can be formulated and resolved precisely. The setting of the toy model is three dimensional Euclidean gravity. Before studying the model in detail, we argue that Loop Quantum Gravity may provide a very useful approach when discussing the question of motion in Quantum Gravity.

Karim Noui

2010-03-31T23:59:59.000Z

367

CHANGE OF NAME TIAA Annuity Number CREF Annuity Number TIAA Policy Number  

E-Print Network (OSTI)

CHANGE OF NAME TIAA Annuity Number CREF Annuity Number TIAA Policy Number Social Security Number and only use black or dark blue ink. Return this form to: TIAA-CREF P.O. Box 1264 Charlotte, NC 28201 NOTE City State Zip Code For TIAA-CREF USE ONLY Accepted -- Teachers Insurance and Annuity Association

Snider, Barry B.

368

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  ...

369

Can quantum computer perform better than classical?  

E-Print Network (OSTI)

A theoretical model of a quantum device which can factorize any number N in two steps i.e. by preparing an input state and performing a measurement is discussed. The analysis reveals that the duration of state preparation and measurement is proportional to N while the energy consumption grows like log N. These results suggest the existence of Heisenberg-type relation putting limits on the efficiency of a quantum computer in terms of a total computation time, a total energy consumption and a classical complexity of the problem.

Robert Alicki

2000-06-05T23:59:59.000Z

370

Can quantum computer perform better than classical?  

E-Print Network (OSTI)

A theoretical model of a quantum device which can factorize any number N in two steps i.e. by preparing an input state and performing a measurement is discussed. The analysis reveals that the duration of state preparation and measurement is proportional to N while the energy consumption grows like log N. These results suggest the existence of Heisenberg-type relation putting limits on the efficiency of a quantum computer in terms of a total computation time, a total energy consumption and a classical complexity of the problem.

Alicki, R

2000-01-01T23:59:59.000Z

371

Some New Aspects of Degenerate Quantum Plasma  

Science Conference Proceedings (OSTI)

Answers to some salient questions, which arise in quantum plasmas, are given. Starting from the Schroedinger equation for a single particle it is demonstrated how the Wigner-Moyal equation can be derived. It is shown that the Wigner-Moyal type of equation also exists in the classical field theory. As an example, from the Maxwell equations the Wigner-Moyal type of equation is obtained for a dense photon gas, which is classical, concluding that the Wigner-Moyal type of equation can be derived for any system, classical or quantum. A new type of quantum kinetic equations are presented. These novel kinetic equations allows to obtain a set of quantum hydrodynamic equations, which is impossible to derive by the Wigner-Moyal equation. The propagation of small perturbations and instabilities of these perturbations are then discussed, presenting new modes of quantum plasma waves. In the case of low frequency oscillations with ions, a new Bogolyubov type of spectrum is found. Furthermore, the Korteweg-de Vries (KdV) equation is derived and the contribution of the Madelung term in the formation of the KdV solitons is discussed.

Tsintsadze, Nodar L. [Department of Plasma Physics, E. Andronikashvii Institute of Physics, Tbilisi (Georgia)

2010-12-14T23:59:59.000Z

372

Quantum Money with Classical Verification  

E-Print Network (OSTI)

We construct a quantum money scheme that allows verification through classical communication with bank. This is the first demonstration that a secure quantum money scheme exists that does not require quantum communication for coin verification.

Gavinsky, Dmitry

2011-01-01T23:59:59.000Z

373

Quantum gravity on the lattice  

E-Print Network (OSTI)

the Conference Quantum Gravity: Challenges and Perspectives.divergences in quantum gravity. In: Hawking, S.W. , Israel,f ) V n?1 ( f ) = Quantum gravity on the lattice Similarly,

Hamber, Herbert W.

2009-01-01T23:59:59.000Z

374

Quantum Communication Technology  

E-Print Network (OSTI)

Quantum communication is built on a set of disruptive concepts and technologies. It is driven by fascinating physics and by promising applications. It requires a new mix of competencies, from telecom engineering to theoretical physics, from theoretical computer science to mechanical and electronic engineering. First applications have already found their way to niche markets and university labs are working on futuristic quantum networks, but most of the surprises are still ahead of us. Quantum communication, and more generally quantum information science and technologies, are here to stay and will have a profound impact on the XXI century.

Gisin, Nicolas

2010-01-01T23:59:59.000Z

375

Quantum Devices Group Homepage  

Science Conference Proceedings (OSTI)

... Quantum Information and Measurements—America's future prosperity and security may ... For magnetic sensors, spin-based transport in metals and ...

2011-10-03T23:59:59.000Z

376

Quantum-based Measurements  

Science Conference Proceedings (OSTI)

... The physical and biological sciences are converging on the nanoscale and the decades ... A new technology frontier is opening—the quantum world. ...

2010-10-05T23:59:59.000Z

377

Recommended Quantum Communications Links  

Science Conference Proceedings (OSTI)

... qubit.nist.gov. NIST's Physical Measurement Laboratory Quantum Physics Division. www.nist.gov/pml/div689/index.cfm. ...

2013-03-14T23:59:59.000Z

378

QUANTUM CONVERSION IN PHOTOSYNTHESIS  

E-Print Network (OSTI)

QUANTUM CONVERSION IN PHOTOSYNTHESIS Melvin Calvin Januaryas it occurs in modern photosynthesis can only take place inof the problem or photosynthesis, or any specific aspect of

Calvin, Melvin

2008-01-01T23:59:59.000Z

379

Quantum Exotic PDE's  

E-Print Network (OSTI)

Following the previous works on the A. Pr\\'astaro's formulation of algebraic topology of quantum (super) PDE's, it is proved that a canonical Heyting algebra ({\\em integral Heyting algebra}) can be associated to any quantum PDE. This is directly related to the structure of its global solutions. This allows us to recognize a new inside in the concept of quantum logic for microworlds. Furthermore, the Prastaro's geometric theory of quantum PDE's is applied to the new category of {\\em quantum hypercomplex manifolds}, related to the well-known Cayley-Dickson construction for algebras. Theorems of existence for local and global solutions are obtained for (singular) PDE's in this new category of noncommutative manifolds. Finally the extension of the concept of exotic PDE's, recently introduced by A.Pr\\'astaro, has been extended to quantum PDE's. Then a smooth quantum version of the quantum (generalized) Poincar\\'e conjecture is given too. These results extend ones for quantum (generalized) Poincar\\'e conjecture, previously given by A. Pr\\'astaro.

Agostino Prástaro

2011-06-04T23:59:59.000Z

380

Quantum Monte Carlo for  

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

Quantum Monte Carlo for the Electronic Structure of Atoms and Molecules Brian Austin Lester Group, U.C. Berkeley BES Requirements Workshop Rockville, MD February 9, 2010 Outline...

Note: This page contains sample records for the topic "quantum numbers shown" 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 Confined Structures  

Science Conference Proceedings (OSTI)

Sep 14, 2009 ... Classification of Energy Levels in Quantum Dot Structures by Means of Depleted Layer Spectroscopy Methods: Maria Kaniewska1; Olof ...

382

NMR Quantum Information Processing  

E-Print Network (OSTI)

Nuclear Magnetic Resonance (NMR) has provided a valuable experimental testbed for quantum information processing (QIP). Here, we briefly review the use of nuclear spins as qubits, and discuss the current status of NMR-QIP. Advances in the techniques available for control are described along with the various implementations of quantum algorithms and quantum simulations that have been performed using NMR. The recent application of NMR control techniques to other quantum computing systems are reviewed before concluding with a description of the efforts currently underway to transition to solid state NMR systems that hold promise for scalable architectures.

Chandrasekhar Ramanathan; Nicolas Boulant; Zhiying Chen; David G. Cory; Isaac Chuang; Matthias Steffen

2004-08-26T23:59:59.000Z

383

Some topics in thermodynamics and quantum mechanics  

E-Print Network (OSTI)

We sketch some connecting relations involving fractional and quantum calculi, fractal structure, thermodynamics, and quantum mechanics.

Robert Carroll

2012-10-29T23:59:59.000Z

384

Quantum mechanics in curved space-time II  

E-Print Network (OSTI)

This paper is a sequence of the work presented in [1], where, the principles of the general relativity have been used to formulate quantum wave equations taking into account the effect of the electromagnetic and strong interactions in the space-time metric of quantum systems. Now, the role of the energy-momentum tensor in this theory is studied, and it is consistent with the formulation of the general quantum mechanics shown in [1]. With this procedure, a dynamical cut-off is generated and the constant $A$ of the field equation is calculated.

C. C. Barros Jr

2005-09-01T23:59:59.000Z

385

Number  

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

NATIONAL ENERGY POLICY NATIONAL ENERGY POLICY STATUS REPORT on Implementation of NEP Recommendations January, 2005 1 NEP RECOMMENDATIONS: STATUS OF IMPLEMENTATION Chapter 1 1. That the President issue an Executive Order to direct all federal agencies to include in any regulatory action that could significantly and adversely affect energy supplies, distribution, or use, a detailed statement of energy effects and alternatives in submissions to the Office of Management and Budget of proposed regulations covered and all notices of proposed regulations published in the Federal Register. STATUS: IMPLEMENTED. In May 2001, President Bush issued Executive Order 13211 requiring federal agencies to include, in any regulatory action that could significantly and

386

The Distribution of Ramsey Numbers  

E-Print Network (OSTI)

We prove that the number of integers in the interval [0,x] that are non-trivial Ramsey numbers r(k,n) (3 order of magnitude (x ln x)**(1/2).

Clark, Lane

2013-01-01T23:59:59.000Z

387

Topological methods in quantum gravity.  

E-Print Network (OSTI)

??The main technical problem with background independent approaches to quantum gravity is inapplicability of standard quantum field theory methods. New methods are needed which would… (more)

Starodubtsev, Artem

2005-01-01T23:59:59.000Z

388

Quantum physics and human values  

Science Conference Proceedings (OSTI)

This report discusses the following concepts: the quantum conception of nature; the quantum conception of man; and the impact upon human values. (LSP).

Stapp, H.P.

1989-09-01T23:59:59.000Z

389

Quantum Mechanics and Black Holes  

E-Print Network (OSTI)

This paper discusses the existence of black holes from the foundations of quantum mechanics. It is found that quantum mechanics rule out a possible gravitational collapse.

Jose N. Pecina-Cruz

2005-11-11T23:59:59.000Z

390

FOURIER TRANSFORM MULTIPLE QUANTUM NMR  

E-Print Network (OSTI)

TRANSFORM MULTIPLE QUANTUM NMR G. Drobny, A. Pines, S.TRANSFO~~ MULTIPLE QUANTUM NMR G. Drobny, A. Pines, S.

Drobny, G.

2011-01-01T23:59:59.000Z

391

Loss of Quantum Coherence and Positivity of Energy Density in Semiclassical Quantum Gravity  

E-Print Network (OSTI)

In the semiclassical quantum gravity derived from the Wheeler-DeWitt equation, the energy density of a matter field loses quantum coherence due to the induced gauge potential from the parametric interaction with gravity in a non-static spacetime. It is further shown that the energy density takes only positive values and makes superposition principle hold true. By studying a minimal massive scalar field in a FRW spacetime background, we illustrate the positivity of energy density and obtain the classical Hamiltonian of a complex field from the energy density in coherent states.

Sang Pyo Kim; Kwang-Sup Soh

1998-07-09T23:59:59.000Z

392

Quantum teleportation between remote atomic-ensemble quantum memories  

E-Print Network (OSTI)

Quantum teleportation and quantum memory are two crucial elements for large-scale quantum networks. With the help of prior distributed entanglement as a "quantum channel", quantum teleportation provides an intriguing means to faithfully transfer quantum states among distant locations without actual transmission of the physical carriers. Quantum memory enables controlled storage and retrieval of fast-flying photonic quantum bits with stationary matter systems, which is essential to achieve the scalability required for large-scale quantum networks. Combining these two capabilities, here we realize quantum teleportation between two remote atomic-ensemble quantum memory nodes, each composed of 100 million rubidium atoms and connected by a 150-meter optical fiber. The spinwave state of one atomic ensemble is mapped to a propagating photon, and subjected to Bell-state measurements with another single photon that is entangled with the spinwave state of the other ensemble. Two-photon detection events herald the succe...

Bao, Xiao-Hui; Li, Che-Ming; Yuan, Zhen-Sheng; Lu, Chao-Yang; Pan, Jian-Wei

2012-01-01T23:59:59.000Z

393

Number: 1394 Description: In what ...  

Science Conference Proceedings (OSTI)

... Number: 1752 Description: When was the Oklahoma City bombing? ... name of the plane that dropped the Atomic Bomb on Hiroshima? ...

2003-02-12T23:59:59.000Z

394

Data Compression with Prime Numbers  

E-Print Network (OSTI)

A compression algorithm is presented that uses the set of prime numbers. Sequences of numbers are correlated with the prime numbers, and labeled with the integers. The algorithm can be iterated on data sets, generating factors of doubles on the compression.

Gordon Chalmers

2005-11-16T23:59:59.000Z

395

Quantum capacity under adversarial quantum noise: arbitrarily varying quantum channels  

E-Print Network (OSTI)

We investigate entanglement transmission over an unknown channel in the presence of a third party (called the adversary), which is enabled to choose the channel from a given set of memoryless but non-stationary channels without informing the legitimate sender and receiver about the particular choice that he made. This channel model is called arbitrarily varying quantum channel (AVQC). We derive a quantum version of Ahlswede's dichotomy for classical arbitrarily varying channels. This includes a regularized formula for the common randomness-assisted capacity for entanglement transmission of an AVQC. Quite surprisingly and in contrast to the classical analog of the problem involving the maximal and average error probability, we find that the capacity for entanglement transmission of an AVQC always equals its strong subspace transmission capacity. These results are accompanied by different notions of symmetrizability (zero-capacity conditions) as well as by conditions for an AVQC to have a capacity described by a single-letter formula. In he final part of the paper the capacity of the erasure-AVQC is computed and some light shed on the connection between AVQCs and zero-error capacities. Additionally, we show by entirely elementary and operational arguments motivated by the theory of AVQCs that the quantum, classical, and entanglement-assisted zero-error capacities of quantum channels are generically zero and are discontinuous at every positivity point.

Rudolf Ahlswede; Igor Bjelakovic; Holger Boche; Janis Noetzel

2010-10-03T23:59:59.000Z

396

Quantum cryptographic system with reduced data loss  

DOE Patents (OSTI)

A secure method for distributing a random cryptographic key with reduced data loss. Traditional quantum key distribution systems employ similar probabilities for the different communication modes and thus reject at least half of the transmitted data. The invention substantially reduces the amount of discarded data (those that are encoded and decoded in different communication modes e.g. using different operators) in quantum key distribution without compromising security by using significantly different probabilities for the different communication modes. Data is separated into various sets according to the actual operators used in the encoding and decoding process and the error rate for each set is determined individually. The invention increases the key distribution rate of the BB84 key distribution scheme proposed by Bennett and Brassard in 1984. Using the invention, the key distribution rate increases with the number of quantum signals transmitted and can be doubled asymptotically.

Lo, Hoi-Kwong (1309, Low Block, Lei Moon House Ap Lei Chau Estate, Hong Kong, HK); Chau, Hoi Fung (Flat C, 42nd Floor, Tower 1, University Heights 23 Pokfield Road, Pokfulam, Hong Kong, HK)

1998-01-01T23:59:59.000Z

397

Quantum cryptographic system with reduced data loss  

DOE Patents (OSTI)

A secure method for distributing a random cryptographic key with reduced data loss is disclosed. Traditional quantum key distribution systems employ similar probabilities for the different communication modes and thus reject at least half of the transmitted data. The invention substantially reduces the amount of discarded data (those that are encoded and decoded in different communication modes e.g. using different operators) in quantum key distribution without compromising security by using significantly different probabilities for the different communication modes. Data is separated into various sets according to the actual operators used in the encoding and decoding process and the error rate for each set is determined individually. The invention increases the key distribution rate of the BB84 key distribution scheme proposed by Bennett and Brassard in 1984. Using the invention, the key distribution rate increases with the number of quantum signals transmitted and can be doubled asymptotically. 23 figs.

Lo, H.K.; Chau, H.F.

1998-03-24T23:59:59.000Z

398

Quantum Invariants of the Pairing Hamiltonian  

E-Print Network (OSTI)

Quantum invariants of the orbit dependent pairing problem are identified in the limit where the orbits become degenerate. These quantum invariants are simultaneously diagonalized with the help of the Bethe ansatz method and a symmetry in their spectra relating the eigenvalues corresponding to different number of pairs is discussed. These quantum invariants are analogous to the well known rational Gaudin magnet Hamiltonians which play the same role in the reduced pairing case (i.e., orbit independent pairing with non degenerate energy levels). It is pointed out that although the reduced pairing and the degenerate cases are opposite of each other, the Bethe ansatz diagonalization of the invariant operators in both cases are based on the same algebraic structure described by the rational Gaudin algebra.

Y. Pehlivan

2008-06-11T23:59:59.000Z

399

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

400

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

Note: This page contains sample records for the topic "quantum numbers shown" 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

QUICK QUANTUM MECHANICS ---Introduction ---  

E-Print Network (OSTI)

QUICK QUANTUM MECHANICS --- Introduction --- The following notes are intended to be a supplement to your study of Liboff's ``Introductory Quantum Mechanics.'' They are not an alternative! My purpose here of Classical Mechanics After Newton found his equations of motion, physicists knew they would have to wait

Jackson, Andrew D.

402

Quantum Physics Einstein's Gravity  

E-Print Network (OSTI)

Quantum Physics confronts Einstein's Gravity Matt Visser Physics Department Washington University Saint Louis USA Science Saturdays 13 October 2001 #12; Quantum Physics confronts Einstein's Gravity and with Einstein's theory of gravity (the general relativity) is still the single biggest theoretical problem

Visser, Matt

403

Ultraviolet Complete Quantum Gravity  

E-Print Network (OSTI)

An ultraviolet complete (UV) quantum gravity theory is formulated in which vertex functions in Feynman graphs are entire functions and the propagating gravitons are described by local, causal propagators. A scalar-tensor action describes classical gravity theory. The cosmological constant problem is investigated in the context of the UV complete quantum gravity.

Moffat, J W

2010-01-01T23:59:59.000Z

404

Quantum Gravity and Turbulence  

E-Print Network (OSTI)

We apply recent advances in quantum gravity to the problem of turbulence. Adopting the AdS/CFT approach we propose a string theory of turbulence that explains the Kolmogorov scaling in 3+1 dimensions and the Kraichnan and Kolmogorov scalings in 2+1 dimensions. In the gravitational context, turbulence is intimately related to the properties of spacetime, or quantum, foam.

Vishnu Jejjala; Djordje Minic; Y. Jack Ng; Chia-Hsiung Tze

2010-05-18T23:59:59.000Z

405

Quantum Game Theory  

E-Print Network (OSTI)

Quantum game theory is the study of strategic behavior by agents with access to quantum technology. Broadly speaking, this technology can be employed in either of two ways: As part of a randomization device or as part of a communications protocol. We survey some of the main ideas from both branches of the subject.

Landsburg, Steven E

2011-01-01T23:59:59.000Z

406

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

407

Is Quantum Search Practical?  

Science Conference Proceedings (OSTI)

Gauging a quantum algorithm's practical significance requires weighing it against the best conventional techniques applied to useful instances of the same problem. The authors show that several commonly suggested applications of Grover's quantum search algorithm fail to offer computational improvements over the best conventional algorithms.

George F. Viamontes; Igor L. Markov; John P. Hayes

2005-01-01T23:59:59.000Z

408

Quantum Spin Systems  

E-Print Network (OSTI)

This article is a short introduction to the general topic of quantum spin systems. After a brief sketch of the history of the subject, the standard mathematical framework for formulating problems and results in quantum spin systems is described. Then, three short sections are devoted to Spontaneaous Symmetry Breaking, Phase transitions, and Dynamcis.

Bruno Nachtergaele

2004-09-02T23:59:59.000Z

409

Quantum solution to a three player Kolkata restaurant problem using entangled qutrits  

E-Print Network (OSTI)

Three player quantum Kolkata restaurant problem is modeled using three entangled qutrits. This first use of three level quantum states in this context is a step towards a $N$-choice generalization of the $N$-player quantum minority game. It is shown that a better than classical payoff is achieved by a Nash equilibrium solution where the space of available strategies is spanned by subsets of SU(3) and the players share a tripartite entangled initial state.

Puya Sharif; Hoshang Heydari

2011-11-08T23:59:59.000Z

410

Features of the electronic spectrum in a type-I core - shell quantum dot  

Science Conference Proceedings (OSTI)

The model is proposed, which allows one to solve the problem of finding the energy spectrum and the wave function of an electron in a type-I core - shell quantum dot. It is shown that the size of the core and shell can serve as control parameters for the optimisation of the energy structure of the quantum dot in order to obtain the real structures with desired electrophysical and optical properties. (quantum dots)

Igoshina, S E; Karmanov, A A [Penza State University, Penza (Russian Federation)

2013-01-31T23:59:59.000Z

411

Quantum scholasticism: On quantum contexts, counterfactuals, and the absurdities of quantum omniscience  

Science Conference Proceedings (OSTI)

Unlike classical information, quantum knowledge is restricted to the outcome of measurements of maximal observables corresponding to single contexts. Keywords: Context, Maximal observables, Omniscience, Quantum information

Karl Svozil

2009-02-01T23:59:59.000Z

412

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

413

Universality in metallic nanocohesion: a quantum chaos approach  

E-Print Network (OSTI)

Convergent semiclassical trace formulae for the density of states and cohesive force of a narrow constriction in an electron gas, whose classical motion is either chaotic or integrable, are derived. It is shown that mode quantization in a metallic point contact or nanowire leads to universal oscillations in its cohesive force: the amplitude of the oscillations depends only on a dimensionless quantum parameter describing the crossover from chaotic to integrable motion, and is of order 1 nano-Newton, in agreement with recent experiments. Interestingly, quantum tunneling is shown to be described quantitatively in terms of the instability of the classical periodic orbits.

C. A. Stafford; F. Kassubek; J. Bürki; H. Grabert

1999-07-07T23:59:59.000Z

414

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

415

Quantum Cryptographic Network based on Quantum Memories Computer Science Department  

E-Print Network (OSTI)

Quantum Cryptographic Network based on Quantum Memories Eli Biham Computer Science Department, Switzerland Tal Mor Department of Physics Technion Haifa 32000, Israel (September 24, 1996) Abstract Quantum transmission of information. We present a quantum cryptographic system, in which users store particles

Biham, Eli

416

Quantum optical experiments and fundamentals of quantum theory  

E-Print Network (OSTI)

Quantum optical experiments and fundamentals of quantum theory Miloslav Dusek Department of Optics, Palacky University 17. listopadu 50, 772 00 Olomouc, Czech Republic ABSTRACT Quantum optics has o ered new possibilities for experimental tests of basic principles of quantum mechanics. It enables us to experimentally

Dusek, Miloslav

417

Quantum Statistical Mechanics and Quantum Computation Thursday, 22 March 2012  

E-Print Network (OSTI)

Quantum Statistical Mechanics and Quantum Computation Thursday, 22 March 2012 8:50 am Welcoming:30 ­ 5:30 "Criticality without frustration for quantum spin-1 chains" Sergey Bravyi 6:30 pm Dinner at Triumph Brewery 138 Nassau Street Princeton, NJ 08542 609-924-7855 Quantum Statistical Mechanics

418

QUANTUM FILTERING OF MARKOV SIGNALS WITH WHITE QUANTUM NOISE  

E-Print Network (OSTI)

QUANTUM FILTERING OF MARKOV SIGNALS WITH WHITE QUANTUM NOISE V. P. BELAVKIN Abstract. Time-continuous non-anticipating quantum processes of nonde- molition measurements are introduced as the dynamical-valued probability measures on the trajectory spaces of the gener- alized temporal observations in quantum open

Belavkin, Viacheslav P.

419

Quantum Imaging: Enhanced Image Formation Using Quantum States of Light  

E-Print Network (OSTI)

Quantum Imaging: Enhanced Image Formation Using Quantum States of Light Robert W. Boyd, Kam Wai, University of Rochester, Rochester, NY 14627, USA ABSTRACT We review recent research in the field of quantum imaging. Quantum imaging deals with the formation of images that possess higher resolution or better

Boyd, Robert W.

420

Projective Plane And Planar Quantum Codes  

E-Print Network (OSTI)

Cellulations of the projective plane RP 2 define single qubit topological quantum error correcting codes since there is a unique essential cycle in H 1 (RP 2 ; Z 2 ). We construct three of the smallest such codes, show they are inequivalent, and identify one of them as Shor's original 9 qubit repetition code. We observe that Shor's code can be constructed in a planar domain and generalize to planar constructions of higher genus codes for multiple qubits. PACS numbers: 03.67.Lx, 89.70.+c, 89.80.+h. AMS subject classification: 94Bxx, 81P99, 57M20. KEY WORDS: topological code, quantum error correction, planar code. Projective plane and planar quantum codes Freedman & Meyer Kitaev has constructed a class of quantum error correcting codes using qubits arranged on the edges of square lattices embedded in the two dimensional torus [1]. While these toric codes are not particularly efficient---they do not come close to saturating the quantum Hamming bound [2]---they are nevertheless inte...

Michael H. Freedman; David A. Meyer

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "quantum numbers shown" 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

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; Fève, Gwendal; Degiovanni, Pascal

2011-01-01T23:59:59.000Z

422

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; Rémy Hervé; Gwendal Fève; Pascal Degiovanni

2011-02-02T23:59:59.000Z

423

General quantum modeling of combining concepts: A quantum field model in Fock space  

E-Print Network (OSTI)

We extend a quantum model in Hilbert space developed in Aerts (2007a) into a quantum field theoric model in Fock space for the modeling of the combination of concepts. Items and concepts are represented by vectors in Fock space and membership weights of items are modeled by quantum probabilities. We apply this theory to model the disjunction of concepts and show that the predictions of our theory for the membership weights of items regarding the disjunction of concepts match with great accuracy the complete set of results of an experiment conducted by Hampton (1988b). It are the quantum effects of interference and superposition of that are at the origin of the effects of overextension and underextension observed by Hampton as deviations from a classical use of the disjunction. It is essential for the perfect matches we obtain between the predictions of the quantum field model and Hampton’s experimental data that items can be in superpositions of ‘different numbers states ’ which proves that the genuine structure of quantum field theory is needed to match predictions with experimental data.

Diederik Aerts

2007-01-01T23:59:59.000Z

424

Quantum discord and other measures of quantum correlation  

E-Print Network (OSTI)

One of the best signatures of nonclassicality in a quantum system is the existence of correlations that have no classical counterpart. Different methods for quantifying the quantum and classical parts of the correlations are amongst the most actively-studied topics of quantum information theory in the past decade. Entanglement is the most prominent of these correlations, but in many cases unentangled states exhibit nonclassical behavior. Thus distinguishing quantum correlation other than entanglement provides a better division between the quantum and classical worlds, especially when considering mixed states. Here we review different notions of classical and quantum correlations quantified by quantum discord and other related measures. In the first half we review the mathematical properties of the measures of quantum correlation, relate them to each other, and discuss the classical-quantum division that is common among them. In the second half, we show that the measures quantum correlation identify and quanti...

Modi, Kavan; Cable, Hugo; Paterek, Tomasz; Vedral, Vlatko

2011-01-01T23:59:59.000Z

425

Nano-wires with surface disorder: Giant localization lengths and quantum-to-classical crossover  

E-Print Network (OSTI)

We investigate electronic quantum transport through nano-wires with one-sided surface roughness. A magnetic field perpendicular to the scattering region is shown to lead to exponentially diverging localization lengths in the quantum-to-classical crossover regime. This effect can be quantitatively accounted for by tunneling between the regular and the chaotic components of the underlying mixed classical phase space.

J. Feist; A. Bäcker; R. Ketzmerick; S. Rotter; B. Huckestein; J. Burgdörfer

2006-06-22T23:59:59.000Z

426

The Quantum Governor: Automatic quantum control and reduction of the influence of noise without measuring  

E-Print Network (OSTI)

The problem of automatically protecting a quantum system against noise in a closed circuit is analyzed. A general scheme is developed built from two steps. At first, a distillation step is induced in which undesired components are removed to another degree of freedom of the system. Later a recovering step is employed which the system gains back its initial density. An Optimal-Control method is used to generate the distilling operator. The scheme is demonstrated by a simulation of a two level byte influenced by white noise. Undesired deviations from the target were shown to be reduced by at least two orders of magnitude on average. The relations between the quantum version of the classical Watt's Governor and the field of quantum information are also discussed.

Kallush, S

2005-01-01T23:59:59.000Z

427

The Quantum Governor: Automatic quantum control and reduction of the influence of noise without measuring  

E-Print Network (OSTI)

The problem of automatically protecting a quantum system against noise in a closed circuit is analyzed. A general scheme is developed built from two steps. At first, a distillation step is induced in which undesired components are removed to another degree of freedom of the system. Later a recovering step is employed which the system gains back its initial density. An Optimal-Control method is used to generate the distilling operator. The scheme is demonstrated by a simulation of a two level byte influenced by white noise. Undesired deviations from the target were shown to be reduced by at least two orders of magnitude on average. The relations between the quantum version of the classical Watt's Governor and the field of quantum information are also discussed.

S. Kallush; R. Kosloff

2005-11-21T23:59:59.000Z

428

Universal Characteristics of Fractal Fluctuations in Prime Number Distribution  

E-Print Network (OSTI)

The frequency of occurrence of prime numbers at unit number spacing intervals exhibits selfsimilar fractal fluctuations concomitant with inverse power law form for power spectrum generic to dynamical systems in nature such as fluid flows, stock market fluctuations, population dynamics, etc. The physics of long-range correlations exhibited by fractals is not yet identified. A recently developed general systems theory visualises the eddy continuum underlying fractals to result from the growth of large eddies as the integrated mean of enclosed small scale eddies, thereby generating a hierarchy of eddy circulations, or an inter-connected network with associated long-range correlations. The model predictions are as follows: (i) The probability distribution and power spectrum of fractals follow the same inverse power law which is a function of the golden mean. The predicted inverse power law distribution is very close to the statistical normal distribution for fluctuations within two standard deviations from the mean of the distribution. (ii) Fractals signify quantumlike chaos since variance spectrum represents probability density distribution, a characteristic of quantum systems such as electron or photon. (ii) Fractal fluctuations of frequency distribution of prime numbers signify spontaneous organisation of underlying continuum number field into the ordered pattern of the quasiperiodic Penrose tiling pattern. The model predictions are in agreement with the probability distributions and power spectra for different sets of frequency of occurrence of prime numbers at unit number interval for successive 1000 numbers. Prime numbers in the first 10 million numbers were used for the study.

A. M. Selvam

2008-11-12T23:59:59.000Z

429

Quantum Complexity and Fundamental Physics  

Science Conference Proceedings (OSTI)

Quantum Complexity and Fundamental Physics. Scott Aaronson Computer Science and Artificial Intelligence Laboratory ...

2010-10-05T23:59:59.000Z

430

Gravity and the quantum potential  

E-Print Network (OSTI)

We review some material connecting gravity and the quantum potential and provide a few new observations.

Robert Carroll

2004-06-02T23:59:59.000Z

431

NIST Quantum Physics Division - 2001  

Science Conference Proceedings (OSTI)

"Technical Activities 2001" - Table of Contents, Division home page. Quantum Physics Division. Division Overview | Program ...

432

NIST Quantum Physics Division - 1999  

Science Conference Proceedings (OSTI)

TECHNICAL ACTIVITIES 1999 - NISTIR 6438 QUANTUM PHYSICS DIVISION. Fermi surface. Absorption images of the ...

433

Direct measure of quantum correlation  

SciTech Connect

The quantumness of the correlation known as quantum correlation is usually measured by quantum discord. So far various quantum discords can be roughly understood as indirect measure by some special discrepancy of two quantities. We present a direct measure of quantum correlation by revealing the difference between the structures of classically and quantum correlated states. Our measure explicitly includes the contributions of the inseparability and local nonorthogonality of the eigenvectors of a density matrix. Besides its relatively easy computability, our measure can provide a unified understanding of quantum correlation of all the present versions.

Yu, Chang-shui [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Zhao, Haiqing [School of Science, Dalian Jiaotong University, Dalian 116028 (China)

2011-12-15T23:59:59.000Z

434

Quantum Process Tomography via L1-norm Minimization  

E-Print Network (OSTI)

For an initially well designed but imperfect quantum information system, the process matrix is almost sparse in an appropriate basis. Existing theory and associated computational methods (L1-norm minimization) for reconstructing sparse signals establish conditions under which the sparse signal can be perfectly reconstructed from a very limited number of measurements (resources). Although a direct extension to quantum process tomography of the L1-norm minimization theory has not yet emerged, the numerical examples presented here, which apply L1-norm minimization to quantum process tomography, show a significant reduction in resources to achieve a desired estimation accuracy over existing methods.

Robert L. Kosut

2008-12-23T23:59:59.000Z

435

Quantum transducer in circuit optomechanics  

E-Print Network (OSTI)

Mechanical resonators are macroscopic quantum objects with great potential. They couple to many different quantum systems such as spins, optical photons, cold atoms, and Bose Einstein condensates. It is however difficult to measure and manipulate the phonon state due to the tiny motion in the quantum regime. On the other hand, microwave resonators are powerful quantum devices since arbitrary photon state can be synthesized and measured with a quantum tomography. We show that a linear coupling, strong and controlled with a gate voltage, between the mechanical and the microwave resonators enables to create quantum phonon states, manipulate hybrid entanglement between phonons and photons and generate entanglement between two mechanical oscillators. In circuit quantum optomechanics, the mechanical resonator acts as a quantum transducer between an auxiliary quantum system and the microwave resonator, which is used as a quantum bus.

Didier, Nicolas; Blanter, Yaroslav M; Fazio, Rosario

2012-01-01T23:59:59.000Z

436

Experimental verification of quantum computations  

E-Print Network (OSTI)

Quantum computers are expected to offer substantial speedups over their classical counterparts and to solve problems that are intractable for classical computers. Beyond such practical significance, the concept of quantum computation opens up new fundamental questions, among them the issue whether or not quantum computations can be certified by entities that are inherently unable to compute the results themselves. Here we present the first experimental verification of quantum computations. We show, in theory and in experiment, how a verifier with minimal quantum resources can test a significantly more powerful quantum computer. The new verification protocol introduced in this work utilizes the framework of blind quantum computing and is independent of the experimental quantum-computation platform used. In our scheme, the verifier is only required to generate single qubits and transmit them to the quantum computer. We experimentally demonstrate this protocol using four photonic qubits and show how the verifier can test the computer's ability to perform measurement-based quantum computations.

Stefanie Barz; Joseph F. Fitzsimons; Elham Kashefi; Philip Walther

2013-08-30T23:59:59.000Z

437

Quantum Suppression of the Rayleigh Instability in Nanowires  

E-Print Network (OSTI)

A linear stability analysis of metallic nanowires is performed in the free-electron model using quantum chaos techniques. It is found that the classical instability of a long wire under surface tension can be completely suppressed by electronic shell effects, leading to stable cylindrical configurations whose electrical conductance is a magic number 1, 3, 5, 6,... times the quantum of conductance. Our results are quantitatively consistent with recent experiments with alkali metal nanowires.

F. Kassubek; C. A. Stafford; Hermann Grabert; Raymond E. Goldstein

2000-06-14T23:59:59.000Z

438

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

439

Quantum Process Nonclassicality  

E-Print Network (OSTI)

We propose a definition of nonclassicality for a single-mode quantum-optical process based on its action on coherent states. If a quantum process transforms a coherent state to a nonclassical state, it is verified to be nonclassical. To identify nonclassical processes, we introduce a representation for quantum processes, called the process-nonclassicality quasiprobability distribution, whose negativities indicate nonclassicality of the process. Using this distribution, we derive a relation for predicting nonclassicality of the output states for a given input state. We experimentally demonstrate our method by considering the single-photon addition as a nonclassical process, and predicting nonclassicality of the output state for an input thermal state.

Saleh Rahimi-Keshari; Thomas Kiesel; Werner Vogel; Samuele Grandi; Alessandro Zavatta; Marco Bellini

2013-02-05T23:59:59.000Z

440

Quantum Mechanics Without Observers  

E-Print Network (OSTI)

The measurement problem and the role of observers have plagued quantum mechanics since its conception. Attempts to resolve these have introduced anthropomorphic or non-realist notions into physics. A shift of perspective based upon process theory and utilizing methods from combinatorial games, interpolation theory and complex systems theory results in a novel realist version of quantum mechanics incorporating quasi-local, nondeterministic hidden variables that are compatible with the no-hidden variable theorems and relativistic invariance, and reproduce the standard results of quantum mechanics to a high degree of accuracy without invoking observers.

W. H. Sulis

2013-02-18T23:59:59.000Z

Note: This page contains sample records for the topic "quantum numbers shown" 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

Dynamic virtual credit card numbers  

Science Conference Proceedings (OSTI)

Theft of stored credit card information is an increasing threat to e-commerce.We propose a dynamic virtual credit card number scheme that reduces the damage caused by stolen credit card numbers. A user can use an existing credit card account to generate ... Keywords: credit card theft, e-commerce

Ian Molloy; Jiangtao Li; Ninghui Li

2007-02-01T23:59:59.000Z

442

On the hypothesis that quantum mechanism manifests classical mechanics: Numerical approach to the correspondence in search of quantum chaos  

SciTech Connect

Quantum manifestation of classical chaos has been one of the extensively studied subjects for more than a decade. Yet clear understanding of its nature still remains to be an open question partly due to the lack of a canonical definition of quantum chaos. The classical definition seems to be unsuitable in quantum mechanics partly because of the Heisenberg quantum uncertainty. In this regard, quantum chaos is somewhat misleading and needs to be clarified at the very fundamental level of physics. Since it is well known that quantum mechanics is more fundamental than classical mechanics, the quantum description of classically chaotic nature should be attainable in the limit of large quantum numbers. The focus of my research, therefore, lies on the correspondence principle for classically chaotic systems. The chaotic damped driven pendulum is mainly studied numerically using the split operator method that solves the time-dependent Schroedinger equation. For classically dissipative chaotic systems in which (multi)fractal strange attractors often emerge, several quantum dissipative mechanisms are also considered. For instance, Hoover`s and Kubo-Fox-Keizer`s approaches are studied with some computational analyses. But the notion of complex energy with non-Hermiticity is extensively applied. Moreover, the Wigner and Husimi distribution functions are examined with an equivalent classical distribution in phase-space, and dynamical properties of the wave packet in configuration and momentum spaces are also explored. The results indicate that quantum dynamics embraces classical dynamics although the classicalquantum correspondence fails to be observed in the classically chaotic regime. Even in the semi-classical limits, classically chaotic phenomena would eventually be suppressed by the quantum uncertainty.

Lee, Sang-Bong

1993-09-01T23:59:59.000Z

443

Quantum Enabled Security (QES) for Optical Communications  

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

Quantum Enabled Security (QES) for Optical Communications Quantum Enabled Security (QES) for Optical Communications Los Alamos National Laboratory has developed Quantum Enabled...

444

Quantum Condensed Matter Division | Neutron Science | ORNL  

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

Quantum Condensed Matter Division SHARE Quantum Condensed Matter Division QCMD Director Steve Nagler The Quantum Condensed Matter Division (QCMD) enables and conducts a broad...

445

Analysis of mechanisms of carrier emission in the p-i-n structures with In(Ga)As quantum dots  

SciTech Connect

With the help of the photocurrent spectroscopy, the mechanism of emission of charge carriers from energy levels of the (In,Ga)As/(Al,Ga)As quantum dots of different design are studied. Thermal activation is shown to be the main mechanism of carrier emission from the quantum dots for the isolated layer of quantum dots separated by wide (Al,Ga)As spacer layers. At a small width of the (Al,Ga)As spacer layer, when electron binding of separate layers of the quantum dots in the vertical direction takes place, the role of the tunneling mechanism of carrier emission between the vertically coupled quantum dots increases.

Shatalina, E. S., E-mail: Shatalina@mail.ioffe.ru; Blokhin, S. A.; Nadtochy, A. M.; Payusov, A. S.; Savelyev, A. V.; Maximov, M. V.; Zhukov, A. E. [St. Petersburg Academic University, Nanotechnology Research and Education Centre (Russian Federation); Ledentsov, N. N. [Russian Academy of Sciences, Ioffe Physical Technical Institute (Russian Federation); Kovsh, A. R.; Mikhrin, S. S.; Ustinov, V. M. [Innolume GmbH (Germany)

2010-10-15T23:59:59.000Z

446

Non-local correlation and quantum discord in two atoms in the non-degenerate model  

SciTech Connect

By using geometric quantum discord (GQD) and measurement-induced nonlocality (MIN), quantum correlation is investigated for two atoms in the non-degenerate two-photon Tavis-Cummings model. It is shown that there is no asymptotic decay for MIN while asymptotic decay exists for GQD. Quantum correlations can be strengthened by introducing the dipole-dipole interaction. The evolvement period of quantum correlation gets shorter with the increase in the dipole-dipole parameter. It is found that there exists not only quantum nonlocality without entanglement but also quantum nonlocality without quantum discord. Also, the MIN and GQD are raised rather than entanglement, and also with weak initial entanglement, there are MIN and entanglement in a interval of death quantum discord. - Highlights: Black-Right-Pointing-Pointer Geometric quantum discord (GQD) and measurement induced nonlocality (MIN) are used to investigate the correlations of two two-level atoms. Black-Right-Pointing-Pointer There is no asymptotic decay for MIN while asymptotic decay exists for GQD. Black-Right-Pointing-Pointer Quantum correlations can be strengthened by introducing the dipole-dipole interaction. Black-Right-Pointing-Pointer There exists not only quantum nonlocality without entanglement but also without discord. Black-Right-Pointing-Pointer Weak initial entanglement leads to MIN and entanglement in intervals of death discord.

Mohamed, A.-B.A., E-mail: Abdelbastm@yahoo.com

2012-12-15T23:59:59.000Z

447

Physical Interpretations of Nilpotent Quantum Mechanics  

E-Print Network (OSTI)

Nilpotent quantum mechanics provides a powerful method of making efficient calculations. More importantly, however, it provides insights into a number of fundamental physical problems through its use of a dual vector space and its explicit construction of vacuum. Physical interpretation of the nilpotent formalism is discussed with respect to boson and baryon structures, the mass-gap problem, zitterbewgung, Berry phase, renormalization, and related issues.

Peter Rowlands

2010-04-09T23:59:59.000Z

448

Integrability vs Quantum Thermalization  

E-Print Network (OSTI)

Non-integrability is often taken as a prerequisite for quantum thermalization. Still, a generally accepted definition of quantum integrability is lacking. With the basis in the driven Rabi model we discuss this careless usage of the term "integrability" in connection to quantum thermalization. The model would be classified as non-integrable according to the most commonly used definitions, for example, the only preserved quantity is the total energy. Despite this fact, a thorough analysis conjectures that the system will not thermalize. Thus, our findings suggest first of all (i) that care should be paid when linking non-integrability with thermalization, and secondly (ii) that the standardly used definitions for quantum integrability are unsatisfactory.

Jonas Larson

2013-04-12T23:59:59.000Z

449

Nonlocality of quantum correlations  

E-Print Network (OSTI)

We show that only those composite quantum systems possessing nonvanishing quantum correlations have the property that any nontrivial local unitary evolution changes their global state. This type of nonlocality occurs also for states that do not violate a Bell inequality, such as, for instance, Werner states with a low degree of entanglement. We derive the exact relation between the global state change induced by local unitary evolutions and the amount of quantum correlations. We prove that the minimal change coincides with the geometric measure of discord, thus providing the latter with an operational interpretation in terms of the capability of a local unitary dynamics to modify a global state. We establish rigorously that Werner states are the maximally quantum correlated two-qubit states, and thus are the ones that maximize this novel type of nonlocality.

Streltsov, A; Roga, W; Bruß, D; Illuminati, F

2012-01-01T23:59:59.000Z

450

Quantum Geometry and Interferometry  

E-Print Network (OSTI)

All existing experimental results are currently interpreted using classical geometry. However, there are theoretical reasons to suspect that at a deeper level, geometry emerges as an approximate macroscopic behavior of a quantum system at the Planck scale. If directions in emergent quantum geometry do not commute, new quantum-geometrical degrees of freedom can produce detectable macroscopic deviations from classicality: spatially coherent, transverse position indeterminacy between any pair of world lines, with a displacement amplitude much larger than the Planck length. Positions of separate bodies are entangled with each other, and undergo quantum-geometrical fluctuations that are not describable as metric fluctuations or gravitational waves. These fluctuations can either be cleanly identified or ruled out using interferometers. A Planck-precision test of the classical coherence of space-time on a laboratory scale is now underway at Fermilab.

Hogan, Craig

2012-01-01T23:59:59.000Z

451

Quantum mechanical Universal constructor  

E-Print Network (OSTI)

Arbitrary quantum states cannot be copied. In fact, to make a copy we must provide complete information about the system. However, can a quantum system self-replicate? This is not answered by the no-cloning theorem. In the classical context, Von Neumann showed that a `universal constructor' can exist which can self-replicate an arbitrary system, provided that it had access to instructions for making copy of the system. We question the existence of a universal constructor that may allow for the self-replication of an arbitrary quantum system. We prove that there is no deterministic universal quantum constructor which can operate with finite resources. Further, we delineate conditions under which such a universal constructor can be designed to operate dterministically and probabilistically.

Pati, A K; Pati, Arun K.; Braunstein, Samuel L.

2003-01-01T23:59:59.000Z

452

Quantum mechanical Universal constructor  

E-Print Network (OSTI)

Arbitrary quantum states cannot be copied. In fact, to make a copy we must provide complete information about the system. However, can a quantum system self-replicate? This is not answered by the no-cloning theorem. In the classical context, Von Neumann showed that a `universal constructor' can exist which can self-replicate an arbitrary system, provided that it had access to instructions for making copy of the system. We question the existence of a universal constructor that may allow for the self-replication of an arbitrary quantum system. We prove that there is no deterministic universal quantum constructor which can operate with finite resources. Further, we delineate conditions under which such a universal constructor can be designed to operate dterministically and probabilistically.

Arun K. Pati; Samuel L. Braunstein

2003-03-19T23:59:59.000Z

453

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

454

TORSION AND QUANTUM GRAVITY  

E-Print Network (OSTI)

more restrictive context of Einstein's theory of gravity.6782 TORSION AND QUANTUM GRAVITY Andrevr J, Him son Lawrencetorsion in conventional gravity cou~d in fact be dynamicaL A

Hanson, Andrew J.

2011-01-01T23:59:59.000Z

455

Quantum-Dense Metrology  

E-Print Network (OSTI)

Quantum metrology utilizes entanglement for improving the sensitivity of measurements. Up to now the focus has been on the measurement of just one out of two non-commuting observables. Here we demonstrate a laser interferometer that provides information about two non-commuting observables, with uncertainties below that of the meter's quantum ground state. Our experiment is a proof-of-principle of quantum dense metrology, and uses the additional information to distinguish between the actual phase signal and a parasitic signal due to scattered and frequency shifted photons. Our approach can be readily applied to improve squeezed-light enhanced gravitational-wave detectors at non-quantum noise limited detection frequencies in terms of a sub shot-noise veto-channel.

Sebastian Steinlechner; Jöran Bauchrowitz; Melanie Meinders; Helge Müller-Ebhardt; Karsten Danzmann; Roman Schnabel

2012-11-15T23:59:59.000Z

456

Terahertz quantum cascade lasers  

E-Print Network (OSTI)

The development of the terahertz frequency range has long been impeded by the relative dearth of compact, coherent radiation sources of reasonable power. This thesis details the development of quantum cascade lasers (QCLs) ...

Williams, Benjamin S. (Benjamin Stanford), 1974-

2003-01-01T23:59:59.000Z

457

Stiff Quantum Polymers  

E-Print Network (OSTI)

At ultralow temperatures, polymers exhibit quantum behavior, which is calculated here for the moments and of the end-to-end distribution in the large-stiffness regime. The result should be measurable for polymers in wide optical traps.

H. Kleinert

2007-01-02T23:59:59.000Z

458

Interpretive Themes in Quantum Physics: Curriculum Development and Outcomes  

E-Print Network (OSTI)

A common learning goal for modern physics instructors is for students to recognize a difference between the experimental uncertainty of classical physics and the fundamental uncertainty of quantum mechanics. Our prior work has shown that student perspectives on the physical interpretation of quantum mechanics can be characterized, and are differentially influenced by the myriad ways instructors approach interpretive themes in their introductory courses. We report how a transformed modern physics curriculum (recently implemented at the University of Colorado) has positively impacted student perspectives on quantum physics, by making questions of classical and quantum reality a central theme of the course, but also by making the beliefs of students (and not just those of scientists) an explicit topic of discussion.

Charles Baily; Noah D. Finkelstein

2011-08-26T23:59:59.000Z

459

Quantum phase transitions in Bose-Fermi systems  

SciTech Connect

Research Highlights: > We study quantum phase transitions in a system of N bosons and a single-j fermion. > Classical order parameters and correlation diagrams of quantum levels are determined. > The odd fermion strongly influences the location and nature of the phase transition. > Experimental evidence for the U(5)-SU(3) transition in odd-even nuclei is presented. - Abstract: Quantum phase transitions in a system of N bosons with angular momentum L = 0, 2 (s, d) and a single fermion with angular momentum j are investigated both classically and quantum mechanically. It is shown that the presence of the odd fermion strongly influences the location and nature of the phase transition, especially the critical value of the control parameter at which the phase transition occurs. Experimental evidence for the U(5)-SU(3) (spherical to axially-deformed) transition in odd-even nuclei is presented.

Petrellis, D., E-mail: dimitris.petrellis@yale.edu [Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06520-8120 (United States); Leviatan, A., E-mail: ami@phys.huji.ac.il [Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel); Iachello, F., E-mail: francesco.iachello@yale.edu [Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06520-8120 (United States)

2011-04-15T23:59:59.000Z

460

Why Do the Quantum Observables Form a Jordan Operator Algebra?  

E-Print Network (OSTI)

The Jordan algebra structure of the bounded real quantum observables was recognized already in the early days of quantum mechanics. While there are plausible reasons for most parts of this structure, the existence of the distributive nonassociative multiplication operation is hard to justify from a physical or statistical point of view. Considering the non-Boolean extension of classical probabilities, presented in a recent paper, it is shown in this paper that such a multiplication operation can be derived from certain properties of the conditional probabilities and the observables, i.e., from postulates with a clear statistical interpretation. The well-known close relation between Jordan operator algebras and C*-algebras then provides the connection to the quantum-mechanical Hilbert space formalism, thus resulting in a novel axiomatic approach to general quantum mechanics that includes the types II and III von Neumann algebras.

Gerd Niestegge

2010-01-21T23:59:59.000Z

Note: This page contains sample records for the topic "quantum numbers shown" 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.


461

Interpretive Themes in Quantum Physics: Curriculum Development and Outcomes  

E-Print Network (OSTI)

A common learning goal for modern physics instructors is for students to recognize a difference between the experimental uncertainty of classical physics and the fundamental uncertainty of quantum mechanics. Our prior work has shown that student perspectives on the physical interpretation of quantum mechanics can be characterized, and are differentially influenced by the myriad ways instructors approach interpretive themes in their introductory courses. We report how a transformed modern physics curriculum (recently implemented at the University of Colorado) has positively impacted student perspectives on quantum physics, by making questions of classical and quantum reality a central theme of the course, but also by making the beliefs of students (and not just those of scientists) an explicit topic of discussion.

Baily, Charles

2011-01-01T23:59:59.000Z

462

Quantum dot conjugates in a sub-micrometer fluidic channel  

DOE Patents (OSTI)

A nanofluidic channel fabricated in fused silica with an approximately 500 nm square cross section was used to isolate, detect and identify individual quantum dot conjugates. The channel enables the rapid detection of every fluorescent entity in solution. A laser of selected wavelength was used to excite multiple species of quantum dots and organic molecules, and the emission spectra were resolved without significant signal rejection. Quantum dots were then conjugated with organic molecules and detected to demonstrate efficient multicolor detection. PCH was used to analyze coincident detection and to characterize the degree of binding. The use of a small fluidic channel to detect quantum dots as fluorescent labels was shown to be an efficient technique for multiplexed single molecule studies. Detection of single molecule binding events has a variety of applications including high throughput immunoassays.

Stavis, Samuel M. (Ithaca, NY); Edel, Joshua B. (Brookline, MA); Samiee, Kevan T. (Ithaca, NY); Craighead, Harold G. (Ithaca, NY)

2008-07-29T23:59:59.000Z

463

Toward fault-tolerant quantum computation without concatenation  

E-Print Network (OSTI)

It has been known that quantum error correction via concatenated codes can be done with exponentially small failure rate if the error rate for physical qubits is below a certain accuracy threshold. Other, unconcatenated codes with their own attractive features—improved accuracy threshold, local operations—have also been studied. By iteratively distilling a certain two-qubit entangled state it is shown how to perform an encoded Toffoli gate, important for universal computation, on CSS codes that are either unconcatenated or, for a range of very large block sizes, singly concatenated. 1 Codes and computation At the end of the long tunnel of experimental quantum computing there is the light of accuracy thresholds provided by quantum error correcting codes. The lengthy computations necessary for efficient factorization and simulation of quantum systems are all of a sudden possible if error rates for qubits are reduced

Eric Dennis

1999-01-01T23:59:59.000Z

464

Quantum bit string sealing  

E-Print Network (OSTI)

Though it was proven that secure quantum sealing of a single classical bit is impossible in principle, here we propose an unconditionally secure quantum sealing protocol which seals a classical bit string. Any reader can obtain each bit of the sealed string with an arbitrarily small error rate, while reading the string is detectable. The protocol is simple and easy to be implemented. The possibility of using this protocol to seal a single bit in practical is also discussed.

Guang-Ping He

2005-02-15T23:59:59.000Z

465

Quantum Harmonic Black Holes  

E-Print Network (OSTI)

Inspired by the recent conjecture that black holes are condensates (of gravitons), we investigate a simple model for the black hole degrees of freedom that is consistent both from the point of view of Quantum mechanics and of General Relativity. Since the two perspectives should converge for small, Planck size, black holes, we expect our construction is useful for understanding the physics of microscopic, quantum black holes.

Casadio, R

2013-01-01T23:59:59.000Z

466

Transverse electric conductivity in quantum collisional plasma in Mermin approach  

E-Print Network (OSTI)

Formulas for transverse conductance in quantum collisional plasma are deduced. The kinetic equation in momentum space in the relaxation approach is used. It is shown, that at $\\hbar\\to 0$ the derived formula transfers to the classical one. It is shown also, that when electron collision frequency tends to null (i.e. plasma becomes collisionless), the conductance formula transfers in the known formula inferred earlier by Lindhard.

Latyshev, A V

2011-01-01T23:59:59.000Z

467

Constant-Energy Quantum Fingerprinting  

E-Print Network (OSTI)

We present a protocol for quantum fingerprinting that, in an ideal implementation, requires only a constant total mean photon number in the communicated signals, independently of the size $n$ of the input bit-strings. The protocol uses states that are arbitrarily close in trace distance to states of $\\order{\\log_2 n}$ qubits, thus exhibiting an exponential separation in communication complexity compared to the classical case. The protocol is robust against experimental imperfections and functions with arbitrarily low probability of error. The basis of our scheme is an implementation of the signal states in terms of a coherent state in a superposition of time-bin modes. Experimentally, this requires only the ability to prepare coherent states of arbitrarily low amplitude and fixed phase, and to interfere them in a balanced beam splitter. The scheme is therefore ready to be realized with current technology. In fact, even in the presence of realistic experimental errors, there exist a large range of input sizes for which our quantum protocol requires communication that can be more than two orders of magnitude smaller than a classical fingerprinting protocol that requires only $2\\sqrt{n}+\\order{1}$ bits of communication.

Juan Miguel Arrazola; Norbert Lütkenhaus

2013-09-19T23:59:59.000Z

468

Hydrodynamical interpretation of quantum mechanics: the momentum distribution  

E-Print Network (OSTI)

The quantum mechanics is considered to be a partial case of the stochastic system dynamics. It is shown that the wave function describes the state of statistically averaged system $$, but not that of the individual stochastic system $\\mathcal{S}_{st}$. It is a common practice to think that such a construction of quantum mechanics contains hidden variables, and it is incompatible with the von Neumann's theorem on hidden variables. It is shown that the original conditions of the von Neumann's theorem are not satisfied. In particular, the quantum mechanics cannot describe the particle momentum distribution. The distribution $w(\\mathbf{p}) =| \\psi_{p%}| ^{2}$ is not a particle momentum distribution at the state $\\psi $, because it cannot be attributed to a wave function. It is closer to the mean momentum distribution, although the two distributions do not coincide exactly.

Yuri A. Rylov

2004-02-15T23:59:59.000Z

469

Gaussian Quantum Reading beyond the Standard Quantum Limit  

E-Print Network (OSTI)

Quantum reading aims at retrieving classical information stored in an optical memory with low energy and high accuracy by exploiting the inherently quantum properties of light. We provide an optimal Gaussian strategy for quantum reading with phase-shift keying encoding that makes use of squeezed coherent light and homodyne detectors to largely outperform the Standard Quantum Limit, even in the presence of loss. This strategy, being feasible with current quantum optical technology, represents a viable prototype for a highly efficient and reliable quantum-enhanced optical reader.

Michele Dall'Arno

2013-02-07T23:59:59.000Z

470

California Natural Gas Number of Residential Consumers (Number of Elements)  

U.S. Energy Information Administration (EIA) Indexed Site

Residential Consumers (Number of Elements) Residential Consumers (Number of Elements) California Natural Gas Number of Residential Consumers (Number of Elements) Decade Year-0 Year-1 Year-2 Year-3 Year-4 Year-5 Year-6 Year-7 Year-8 Year-9 1980's 7,626 7,904,858 8,113,034 8,313,776 1990's 8,497,848 8,634,774 8,680,613 8,726,187 8,790,733 8,865,541 8,969,308 9,060,473 9,181,928 9,331,206 2000's 9,370,797 9,603,122 9,726,642 9,803,311 9,957,412 10,124,433 10,329,224 10,439,220 10,515,162 10,510,950 2010's 10,542,584 10,625,190 10,681,916 - = No Data Reported; -- = Not Applicable; NA = Not Available; W = Withheld to avoid disclosure of individual company data. Release Date: 12/12/2013 Next Release Date: 1/7/2014 Referring Pages: Number of Natural Gas Residential

471

Troubles with quantum anisotropic cosmological models: loss of unitarity  

E-Print Network (OSTI)

The anisotropic Bianchi I cosmological model coupled with perfect fluid is quantized in the minisuperspace. The perfect fluid is described by using the Schutz formalism which allows to attribute dynamical degrees of freedom to matter. It is shown that the resulting model is non-unitary. This breaks the equivalence between the many-worlds and dBB interpretations of quantum mechanics.

F. G. Alvarenga; A. B. Batista; J. C. Fabris; S. V. B. Goncalves

2004-02-25T23:59:59.000Z

472

Asymptotic freedom in low-energy quantum gravity  

E-Print Network (OSTI)

It is suggested in the model of low-energy quantum gravity by the author, that the background of super-strong interacting gravitons exists. It is shown here that micro-particles at very small distances should be almost free if the gravitational attraction is caused by a pressure of these gravitons.

Ivanov, Michael A

2008-01-01T23:59:59.000Z

473

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. Côté; H. A. Fertig

2008-01-01T23:59:59.000Z

474

Decoherence in quantum walks – a review  

Science Conference Proceedings (OSTI)

The development of quantum walks in the context of quantum computation, as generalisations of random walk techniques, has led rapidly to several new quantum algorithms. These all follow a unitary quantum evolution, apart from the final measurement. Since ...

Viv Kendon

2007-12-01T23:59:59.000Z

475

Quantum Mechanics and Representation Theory Columbia University  

E-Print Network (OSTI)

Quantum Mechanics and Representation Theory Peter Woit Columbia University Texas Tech, November 21 2013 Peter Woit (Columbia University) Quantum Mechanics and Representation Theory November 2013 1 / 30 #12;Does Anyone Understand Quantum Mechanics? "No One Understands Quantum Mechanics" "I think

Woit, Peter

476

Quantum computation beyond the circuit model  

E-Print Network (OSTI)

The quantum circuit model is the most widely used model of quantum computation. It provides both a framework for formulating quantum algorithms and an architecture for the physical construction of quantum computers. However, ...

Jordan, Stephen Paul

2008-01-01T23:59:59.000Z

477

Multiparty quantum protocols for assisted entanglement distillation  

Science Conference Proceedings (OSTI)

Quantum information theory is a multidisciplinary field whose objective is to understand what happens when information is stored in the state of a quantum system. Quantum mechanics provides us with a new resource, called quantum entanglement, ...

Nicolas Dutil

2011-01-01T23:59:59.000Z

478

Quantum Information Paradox: Real or Fictitious?  

E-Print Network (OSTI)

One of the outstanding puzzles of theoretical physics is whether quantum information indeed gets lost in the case of Black Hole (BH) evaporation or accretion. Let us recall that Quantum Mechanics (QM) demands an upper limit on the acceleration of a test particle. On the other hand, it is pointed out here that, if a Schwarzschild BH would exist, the acceleration of the test particle would blow up at the event horizon in violation of QM. Thus the concept of an exact BH is in contradiction of QM and quantum gravity (QG). It is also reminded that the mass of a BH actually appears as an INTEGRATION CONSTANT of Einstein equations. And it has been shown that the value of this integration constant is actually zero. Thus even classically, there cannot be finite mass BHs though zero mass BH is allowed. It has been further shown that during continued gravitational collapse, radiation emanating from the contracting object gets trapped within it by the runaway gravitational field. As a consequence, the contracting body attains a quasi-static state where outward trapped radiation pressure gets balanced by inward gravitational pull and the ideal classical BH state is never formed in a finite proper time. In other words, continued gravitational collapse results in an "Eternally Collapsing Object" which is a ball of hot plasma and which is asymptotically approaching the true BH state with M=0 after radiating away its entire mass energy. And if we include QM, this contraction must halt at a radius suggested by highest QM acceleration. In any case no EH is ever formed and in reality, there is no quantum information paradox.

Abhas Mitra

2009-11-18T23:59:59.000Z

479

Conservation-Law-Induced Quantum Limits for Physical Realizations of the Quantum NOT Gate  

E-Print Network (OSTI)

In recent investigations, it has been found that conservation laws generally lead to precision limits on quantum computing. Lower bounds of the error probability have been obtained for various logic operations from the commutation relation between the noise operator and the conserved quantity or from the recently developed universal uncertainty principle for the noise-disturbance trade-off in general measurements. However, the problem of obtaining the precision limit to realizing the quantum NOT gate has eluded a solution from these approaches. Here, we develop a new method for this problem based on analyzing the trace distance between the output state from the realization under consideration and the one from the ideal gate. Using the mathematical apparatus of orthogonal polynomials, we obtain a general lower bound on the error probability for the realization of the quantum NOT gate in terms of the number of qubits in the control system under the conservation of the total angular momentum of the computational qubit plus the the control system along the direction used to encode the computational basis. The lower bound turns out to be more stringent than one might expect from previous results. The new method is expected to lead to more accurate estimates for physical realizations of various types of quantum computations under conservation laws, and to contribute to related problems such as the accuracy of programmable quantum processors.

Tokishiro Karasawa; Masanao Ozawa

2007-05-14T23:59:59.000Z

480

Hyper-parallel photonic quantum computation with coupled quantum dots  

E-Print Network (OSTI)

It is well known that a parallel quantum computer is more powerful than a classic computer. By far, there are some important works about the construction of universal quantum logic gates, key elements in quantum computation. However, all existing quantum gates are focused on operating on one degree of freedom (DOF) of quantum systems. Here, we investigate the possibility of achieving the scalable hyper-parallel quantum computation based on two DOFs of photon systems. We construct a deterministic hyper-controlled-not (hyper-CNOT) gate operating on both the spatial-mode and the polarization DOFs of a two-photon system simultaneously, by exploiting the giant optical circular birefringence induced by quantum-dot spins in double-sided optical microcavities as a result of cavity quantum electrodynamics. We analyze the experimental feasibility of this hyper-CNOT gate, concluding that it can be implemented with current technology.

Bao-Cang Ren; Fu-Guo Deng

2013-09-01T23:59:59.000Z

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481

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

482

The Small Quantum Group as a Quantum Double  

E-Print Network (OSTI)

We prove that the quantum double of the quasi-Hopf algebra View the MathML source of We prove that the quantum double of the quasi-Hopf algebra Aq(g)

Etingof, Pavel I.

483

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

484

Multiple Vertically Stacked Quantum Dots, Quantum Wires and ...  

Science Conference Proceedings (OSTI)

On the other hand, it is proposed that the presence of quantum dots in the InGaN active region result in high external quantum efficiency despite the high ...

485

Quantum Electronics and Photonics Division Homepage  

Science Conference Proceedings (OSTI)

... The mission of the Quantum Electronics and Photonics Division is to ... quantum information and computing, optical and electrical waveform metrology ...

2013-02-20T23:59:59.000Z

486

An algorithm for minimization of quantum cost  

E-Print Network (OSTI)

A new algorithm for minimization of quantum cost of quantum circuits has been designed. The quantum cost of different quantum circuits of particular interest (eg. circuits for EPR, quantum teleportation, shor code and different quantum arithmetic operations) are computed by using the proposed algorithm. The quantum costs obtained using the proposed algorithm is compared with the existing results and it is found that the algorithm has produced minimum quantum cost in all cases.

Anindita Banerjee; Anirban Pathak

2009-10-12T23:59:59.000Z

487

Quantum Nature of Light and Matter  

Science Conference Proceedings (OSTI)

Quantum Nature of Light and Matter. to explore fundamental aspects of the quantum nature of light and its interaction with ...

2012-05-30T23:59:59.000Z

488

References - symmetrization postulate of quantum mechanics  

Science Conference Proceedings (OSTI)

... Paul Teller, An Interpretative Introduction to Quantum ... Body Systems, 2nd ed. (Academic Press ... Edward Witten, "Duality, Spacetime and Quantum ...

489

On a New Form of Quantum Mechanics  

E-Print Network (OSTI)

We propose a new form of nonrelativistic quantum mechanics which is based on a quantum version of the action principle.

N. N. Gorobey; A. S. Lukyanenko

2008-07-22T23:59:59.000Z

490

Quantum Computation and Simulation with Neutral Atoms  

Science Conference Proceedings (OSTI)

... Summary: Quantum information processing seeks to use the features of quantum physics to accomplish otherwise intractable computational tasks. ...

2013-01-29T23:59:59.000Z

491

Quantum Dot Fluorescence Lifetime Engineering with DNA ...  

Science Conference Proceedings (OSTI)

Quantum Dot Fluorescence Lifetime Engineering with DNA Origami ... such as metal nanoparticles and semiconductor quantum dots – is challenging ...

492

NIST Demonstrates Better Memory with Quantum Computer ...  

Science Conference Proceedings (OSTI)

... to demonstrate a quantum physics version of computer memory lasting ... prospects for making practical, reliable quantum computers (which make ...

2013-01-03T23:59:59.000Z

493

NIST 'Quantum Tuning Forks' Demonstrate Directly Coupling ...  

Science Conference Proceedings (OSTI)

... for quantum simulations, which may help explain the mechanisms of complex quantum systems such as high-temperature superconductors. ...

2011-03-02T23:59:59.000Z

494

A bird's eye view of quantum computers  

E-Print Network (OSTI)

Quantum computers are discussed in the general framework of computation, the laws of physics and the foundations of quantum mechanics.

Giuliano Benenti; Giuliano Strini

2007-03-13T23:59:59.000Z

495

Interferometers as Probes of Planckian Quantum Geometry  

E-Print Network (OSTI)

A theory of position of massive bodies is proposed that results in an observable quantum behavior of geometry at the Planck scale, $t_P$. Departures from classical world lines in flat spacetime are described by Planckian noncommuting operators for position in different directions, as defined by interactions with null waves. The resulting evolution of position wavefunctions in two dimensions displays a new kind of directionally-coherent quantum noise of transverse position. The amplitude of the effect in physical units is predicted with no parameters, by equating the number of degrees of freedom of position wavefunctions on a 2D spacelike surface with the entropy density of a black hole event horizon of the same area. In a region of size $L$, the effect resembles spatially and directionally coherent random transverse shear deformations on timescale $\\approx L/c$ with typical amplitude $\\approx \\sqrt{ct_PL}$. This quantum-geometrical "holographic noise" in position is not describable as fluctuations of a quantized metric, or as any kind of fluctuation, dispersion or propagation effect in quantum fields. In a Michelson interferometer the effect appears as noise that resembles a random Planckian walk of the beamsplitter for durations up to the light crossing time. Signal spectra and correlation functions in interferometers are derived, and predicted to be comparable with the sensitivities of current and planned experiments. It is proposed that nearly co-located Michelson interferometers of laboratory scale, cross-correlated at high frequency, can test the Planckian noise prediction with current technology.

Craig J. Hogan

2010-02-25T23:59:59.000Z

496

Discrete Quantum Spectrum of Observable Correlations from Inflation  

E-Print Network (OSTI)

The decoherence of quantum fluctuations into classical perturbations during inflation is discussed. A simple quantum mechanical argument, using a spatial particle wavefunction rather than a field description, shows that observable correlations from inflation must have a discrete spectrum, since they originate and freeze into the metric within a compact region. The number of discrete modes is estimated using a holographic bound on the number of degrees of freedom. The discreteness may be detectable in some models; for example, if there is a fundamental universal frequency spectrum, the inflationary gravitational wave background may be resolvable into discrete emission lines.

Craig J. Hogan

2005-04-16T23:59:59.000Z

497

Stochastic Low Reynolds Number Swimmers  

E-Print Network (OSTI)

As technological advances allow us to fabricate smaller autonomous self-propelled devices, it is clear that at some point directed propulsion could not come from pre-specified deterministic periodic deformation of the swimmer's body and we need to develop strategies to extract a net directed motion from a series of random transitions in the conformation space of the swimmer. We present a theoretical formulation to describe the "stochastic motor" that drives the motion of low Reynolds number swimmers based on this concept, and use it to study the propulsion of a simple low Reynolds number swimmer, namely, the three-sphere swimmer model. When the detailed-balanced is broken and the motor is driven out of equilibrium, it can propel the swimmer in the required direction. The formulation can be used to study optimal design strategies for molecular-scale low Reynolds number swimmers.

Ramin Golestanian; Armand Ajdari

2009-01-12T23:59:59.000Z

498

Document ID Number: RL-721  

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

Document ID Number: Document ID Number: RL-721 REV 4 NEPA REVIEW SCREENING FORM DOE/CX-00066 I. Project Title: Nesting Bird Deterrent Study at the 241-C Tank Farm CX B3.8, "Outdoor Terrestrial Ecological and Environmental Research" II. Project Description and Location (including Time Period over which proposed action will occur and Project Dimensions - e.g., acres displaced/disturbed, excavation length/depth, area/location/number of buildings, etc.): Washington River Protection Solutions LLC (WRPS) will perform an outdoor, terrestrial ecological research study to attempt to control and deter nesting birds at the 241-C Tank Farm. This will be a preventative study to test possible methods for controlling &/or minimizing the presence and impacts of nesting birds inside the tank farm. A nesting bird

499

The Quantum Configuration Space of Loop Quantum Cosmology  

E-Print Network (OSTI)

The article gives an account of several aspects of the space known as the Bohr compactification of the line, featuring as the quantum configuration space in loop quantum cosmology, as well as of the corresponding configuration space realization of the so-called polymer representation. Analogies with loop quantum gravity are explored, providing an introduction to (part of) the mathematical structure of loop quantum gravity, in a technically simpler context.

J. M. Velhinho

2007-04-18T23:59:59.000Z

500

Quantum Feedback Networks John Gough,Wales  

E-Print Network (OSTI)

Quantum Feedback Networks John Gough,Wales Matt James,ANU #12;· Quantum Feedback · Quantum Networks - I · Classical Electrical Networks · Quantum Networks - II · Examples in Quantum Control Outline #12;· J. Gough and M.R. James, The Series Product and Its Application to Quantum Feedforward and Feedback

James, Matthew