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Displaying 926 - 950 of 956

Enhanced Quantum State Detection Efficiency Through Quantum Information Processing

October 1, 2005
Author(s)
T Schaetz, M D. Barrett, D. Leibfried, J. Britton, J. Chiaverini, W M. Itano, J. D. Jost, Emanuel Knill, C. Langer, David J. Wineland
The n-qubit concurrence canonical decomposition (CCD) is a generalization of the two-qubit canonical decomposition SU(4)=[SU(2) (x) SU(2)] ? [SU(2) (x) SU(2)], where ? is the commutative group which phases the maximally entangled Bell basis. A prequel

Quantum Computing with Realistically Noisy Devices

October 1, 2005
Author(s)
Emanuel H. Knill
There are quantum algorithms that can efficiently simulate quantum physics, factor large numbers and estimate integrals. As a result, quantum computers can solve otherwise intractable computational problems. One of the main problems of experimental quantum

Stability of Global Entanglement in Thermal States of Spin Chains

October 1, 2005
Author(s)
Stephen Bullock, G K. Brennen
The n-qubit concurrence canonical decomposition (CCD) is a generalization of the two-qubit canonical decomposition SU(4)=[SU(2) (x) SU(2)] ? [SU(2) (x) SU(2)], where ? is the commutative group which phases the maximally entangled Bell basis. A prequel

High resolution, high collection efficiency in numerical aperture increasing lens microscopy of individual quantum dots

August 9, 2005
Author(s)
Zhiheng H. Liu, B. B. Goldberg, Stephen B. Ippolito, Anthony N. Vamivakas, M. S. Unlu, Richard Mirin
We demonstrate the application of a subsurface solid immersion technique to the photoluminescence spectroscopy of individual quantum dots. Contrasted with the conventional solid immersion microscopy, we used a numerical aperture increasing lens and moved

Implementation of the Semiclassical Quantum Fourier Transform in a Scalable System

May 1, 2005
Author(s)
J. Chiaverini, J. Britton, D. Leibfried, Emanuel Knill, M D. Barrett, R. B. Blakestad, W M. Itano, J. D. Jost, C. Langer, R Ozeri, T Schaetz, D Britton, David J. Wineland
The n-qubit concurrence canonical decomposition (CCD) is a generalization of the two-qubit canonical decomposition SU(4)=[SU(2) (x) SU(2)] ? [SU(2) (x) SU(2)], where ? is the commutative group which phases the maximally entangled Bell basis. A prequel

Liquid-state NMR Simulations of Quantum Many-body Problems

April 1, 2005
Author(s)
C. Negrevergne, Rolando Somma, Gerardo Ortiz, Emanuel Knill, R. Laflamme
The n-qubit concurrence canonical decomposition (CCD) is a generalization of the two-qubit canonical decomposition SU(4)=[SU(2) (x) SU(2)] ? [SU(2) (x) SU(2)], where ? is the commutative group which phases the maximally entangled Bell basis. A prequel

Matrix Decompositions and Quantum Circuit Design

December 1, 2004
Author(s)
Stephen Bullock
The n-qubit concurrence canonical decomposition (CCD) is a generalization of the two-qubit canonical decomposition SU(4)=[SU(2) (x) SU(2)] ? [SU(2) (x) SU(2)], where ? is the commutative group which phases the maximally entangled Bell basis. A prequel

Realization of Quantum Error Correction

December 1, 2004
Author(s)
J. Chiaverini, D. Leibfried, T Schaetz, M D. Barrett, R. B. Blakestad, J. Britton, W M. Itano, J. D. Jost, Emanuel Knill, C. Langer, R Ozeri, David J. Wineland
The n-qubit concurrence canonical decomposition (CCD) is a generalization of the two-qubit canonical decomposition SU(4)=[SU(2) (x) SU(2)] ? [SU(2) (x) SU(2)], where ? is the commutative group which phases the maximally entangled Bell basis. A prequel

Photonic Technologies for Quantum Information Processing

October 2, 2004
Author(s)
Prem Kumar, P G. Kwiat, Alan L. Migdall, Sae Woo Nam, Jelena Vuckovic, F Wong
The last several years have seen tremendous research toward practical optical quantum information processing, including single- and entangled-photon sources and high-efficiency photon counting detectors, covering a range of wavelengths. We review some of

Nature and Measure of Entanglement in Quantum Phase Transactions

October 1, 2004
Author(s)
Rolando Somma, Gerardo Ortiz, Howard Barnum, Emanuel Knill, Lorenza Viola
The n-qubit concurrence canonical decomposition (CCD) is a generalization of the two-qubit canonical decomposition SU(4)=[SU(2) (x) SU(2)] ? [SU(2) (x) SU(2)], where ? is the commutative group which phases the maximally entangled Bell basis. A prequel

Temperature-dependent, single quantum dot single photon statistics

May 16, 2004
Author(s)
Richard P. Mirin
We describe temperature-dependent photon antibunching measurements from single InGaAs/GaAs quantum dots. The second order intensity correlation demonstrates single emitter emission up to 120 K and nonclassical light emission to 135 K.

Banishing Quasiparticles From Josephson-Junction Qubits: Why and How To Do It

June 1, 2003
Author(s)
Kristine Lang, Sae Woo Nam, Joe Aumentado, John M. Martinis, C Urbina
Current-biased Josephson junctions are prime candidates for the implementation of quantum bits; however, a present limitation is their coherence time. In this paper we qualitatively describe the role of quasiparticles in decoherence. We discuss two methods

Tungsten Transition-Edge Sensors for IR/Optical/UV Photon Counting

June 1, 2003
Author(s)
Aaron J. Miller, Sae Woo Nam, John M. Martinis, Alexander V. Sergienko
Tungsten transition-edge sensors have been demonstrated to have impressive photon-counting capabilities. Of particular interest is the expected impact to the applications of low-flux astronomy and photonic quantum information. The combination of high

Decoherence of a Superconducting Qubit due to Bias Noise

March 25, 2003
Author(s)
John M. Martinis, Sae Woo Nam, Joe Aumentado, Kristine Lang, C Urbina
We calculate for the current-biased Josephson junction the decoherence of the qubit state from noise and dissipation. The effect of dissipation can be entirely accounted for through a noise model of the current bias that appropriately includes the effect

Quantum Computing and Communication

June 28, 2002
Author(s)
Paul E. Black, David R. Kuhn, Carl J. Williams
A quantum computer, if built, will be to an ordinary computer as a hydrogen bomb is to gunpowder, at least for some types of computations. Today no quantum computer exists, beyond laboratory prototypes capable of solving only tiny problems, and many

Migdall Responds II: More Correlated Photon Metrology History

November 1, 1999
Author(s)
Alan L. Migdall
I appreciate the comments of Mike Gruntman (Sept., page 80) concerning the history of using correlated pairs of particles(photons) to determine absolute detector quantum efficiencies. Unfortunately there is an overall misunderstanding of the technique

Migdall Responds

May 1, 1999
Author(s)
Alan L. Migdall
I thank Duane Jaecks for pointing out earlier origins of the first of the correlated photon metrology applications described in my article - absolute detector quantum efficiency. The work in these early references is helpful in putting the technique in a
Displaying 926 - 950 of 956
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