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We investigate an efficient scheme for generating ultraviolet single-photons s,300 nmd. The scheme combines the highly efficient single-photon four-wave mixing scheme and fast developing quantum dot singlephotons on demand source technology. We show that
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
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
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
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
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.
We propose a scheme to achieve the entanglement of N photon modes (frequency modes) with perfectly efficient ultraslow multiwave mixing in a cold atomic medium. In addition, the method provides an efficient approach to realizing frequency tunability.
We propose a method to achieve quantum entanglement of two Fock states with perfectly efficient, ultraslow propagation enhanced four-wave mixing. A cold atomic medium is illuminated with a twomode cw control laser to produce coherent mixtures of excited
Aaron J. Miller, Sae Woo Nam, John M. Martinis, A. Sergeinko
We have demonstrated a system capable of directly measuring the photon-number state of a single pulse of light using a superconducting transition-edge sensor microcalorimeter. We verify the photon-number distribution of a weak pulsed-laser source at 1550
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
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
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
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
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
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
Eric Dauler, Gregg Jaeger, A Muller, Alan L. Migdall
An investigation is made of a recently introduced quantum interferometric method capable of measuring polarization mode dispersion (PMD) on sub-femtosecond scales, without the usual interferometric stability problems associated with such small time scales
Simon G. Kaplan, Leonard M. Hanssen, Alan L. Migdall, G Lefever-Button
We have performed transmittance measurements of metal-film neutral density filters on ultrathin polymer substrates using both Fourier-transform infrared spectrometer and laser-based (3.39 mm and 10.6 mm) systems. The use of ultrathin substrates, free of
Quantum networks with independent sources of entanglement (hidden variables) and nodes that execute joint quantum measurements can create strong quantum correlations spanning the breadth of the network. Understanding of these correlations has to the
Raymond W. Simmonds, Jose A. Aumentado, Kurt Jacobs, Bryan Gard
While relatively easy to engineer, transverse coupling between a qubit and a cavity mode satisfies the criteria for a quantum non-demolition (QND) measurement only if the coupling between the qubit and cavity is much less than their mutual detuning. This