U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications

NIST Authors in Bold

Displaying 851 - 871 of 871

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

Characterization of High-OD Ultrathin Infrared Neutral Density Filters

October 8, 1998
Author(s)
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

A Bell Inequality for a Class of Multilocal Ring Networks

Author(s)
Michael R. Frey
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
Displaying 851 - 871 of 871