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 by:

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 101 - 125 of 154

Measurement of the Zero Crossing in a Feshbach Resonance of Fermionic 6 Li

October 1, 2002
Author(s)
K M. O'Hara, S L. Hemmer, M E. Granade, M E. Gehm, J E. Thomas, V Venturi, Eite Tiesinga, Carl J. Williams
We measure a zero crossing in the scattering length of a mixture of the two lowest hyperfine states of 6Li. To locate the zero crossing, we monitor the decrease in temperature and atom number arising from evaporation in a CO2 laser trap as a function of

Predissociations in the 0 u + and 1 g States of K 2

October 1, 2002
Author(s)
T Bergeman, Paul S. Julienne, Carl J. Williams, Eite Tiesinga, M R. Manaa, H Wang, P L. Gould, W C. Stwalley
Recently Wang, Gould and Stwalley showed by exciting atomic fragments that predissociation occurs in the Ig and O + u states of K2. In this study, we supplement the interpretation given in the original report with a more detaileddiscussion. The

Creation of a Molecular Condensate by Dynamically Melting a Mott Insulator

July 1, 2002
Author(s)
D Jaksch, V Venturi, J I. Cirac, Carl J. Williams, W.H. Zoller
We propose creation of a molecular Bose-Einstein condensate (BEC) by loading an atomic BEC into an optical lattice and driving it into a Mott insulator (MI) phase with exactly two atoms per site. Molecules in a MI state are then created under well defined

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

Designing Neutral-Atom Nanotraps With Integrated Optical Waveguides

April 1, 2002
Author(s)
J P. Burke, S G. Chu, Garnett W. Bryant, Carl J. Williams, Paul S. Julienne
Integrated optical structures offer the intriguing potential of compact, reproducible waveguide arrays, rings, Y-junctions, etc, that could be used to design evanescent field traps to transport, store, and interact atoms in networks as complicated as any

Quantum Encounters of the Cold Kind

March 1, 2002
Author(s)
K Burnett, Paul S. Julienne, Paul D. Lett, Eite Tiesinga, Carl J. Williams
Ultra cold atomic collisions have a broad impact in experimental and theoretical atomic physics. These encounters occur in a domain where the quantum mechanical aspects of the interacting particles are manifest, since the de Broglie wavelength is enormous

Optimizing a Phase Gate Using Quantum Interference

February 1, 2002
Author(s)
E Charron, Eite Tiesinga, F H. Mies, Carl J. Williams
A controlled interference is proposed to reduce, by two orders of magnitude, the decoherence of a quantum gate for which the gate fidelity is limited by coupling to states other than the |0> and |1> qubit states. This phenomenon is demonstrated in an

Quantum Logic for Trapped Atoms Via Molecular Hyperfine Interactions

February 1, 2002
Author(s)
G K. Brennen, I H. Deutsch, Carl J. Williams
We study the deterministic entanglement of a pair of neutral atoms trapped in an optical lattice by coupling to excited-state molecular hyperfine potentials. Information can be encoded in the ground-state hyperfine levels and processed by bringing atoms

A High Speed Quantum Communication Testbed

January 1, 2002
Author(s)
Carl J. Williams, X Tang, M Hiekkero, J Rouzaud, R Lu, A Goedecke, Alan L. Migdall, A Mink, A Nakassis, Leticia S. Pibida, J Wen, Edward W. Hagley, Charles W. Clark

Quantum Gates Using Motional States in an Optical Lattice

June 1, 2001
Author(s)
E Charron, Eite Tiesinga, F H. Mies, Carl J. Williams
We Study an implementation of a two-qubit universal quantum gate with neutral 87Rb atoms trapped in a far-detuned two-color optical lattice. The qubit states and represent the ground and first excited motional states of an atom in a laser induced potential

Collisional Frequency Shifts in 133 Cs Fountain Clocks

April 1, 2001
Author(s)
P J. Leo, Paul S. Julienne, F H. Mies, Carl J. Williams
We present a theoretical analysis of the pressure shift in Cs fountain clocks using the highly constrained binary collision model described by Leo et al. [Phys. Rev. Lett. xx, xx (2000)]. We predict a reversal in the pressure shift at temperatures near 0

Trapping Atoms With Evanescent Light Fields From Integrated Optical Waveguides

January 1, 2001
Author(s)
J P. Burke, S T. Chu, Garnett W. Bryant, Carl J. Williams, P S. Julience
We theoretically investigate three approaches to trapping atoms above linear integrated optical waveguides. A two-color scheme balances the decaying evanescent fields of red-and blue-detuned light to produce a potential minimum above the guide. A one-color

Ground State Scattering Lengths for Potassium Isotopes Determined by Double-Resonance Photoassociative Spectroscopy of Ultracold 39 K

November 1, 2000
Author(s)
Haonan Wang, A N. Nikolov, J R. Ensher, P L. Gould, E E. Eyler, W C. Stwalley, J P. Burke, J L. Bohn, C H. Greene, Eite Tiesinga, Carl J. Williams, Paul S. Julienne
We use double-resonance photoassociative spectroscopy of ultracold 39K atoms to precisely determine the triplet a 3Σ scattering length for the various isotopes of potassium. Photoassociation of free 39K atoms to the pure long-range 0 (v' = O, J' = 2) level

Collision Properties of Ultracold 133 Cs Atoms

September 1, 2000
Author(s)
P J. Leo, Carl J. Williams, Paul S. Julienne
We present a theoretical analysis of numerous magnetically tunable Feshbach resonances measured by Vladan et al. at fields of up to 25 m T. This analysis provides the most accurate characterization of the collisional properties of ground state Cs atoms

Interacting Atoms Under Strong Quantum Confinement

June 1, 2000
Author(s)
Eite Tiesinga, Carl J. Williams, F H. Mies, Paul S. Julienne
We calculate the energy level shifts of a tightly-confined trapped alkali atom in the presence of a second trapped atom. A complete microscopic description of the interaction energy between the two atoms is used. This allows us to study tightly-confined

Four-Wave Mixing With Multiple Spin States

February 1, 2000
Author(s)
J P. Burke, Carl J. Williams, Paul S. Julienne, Y B. Band, M Trippenbach
Four-wave mixing is a common process in nonlinear optics wherein the nonlinear interaction between light and matter allows three light waves to interact or mix and produce a fourth wave with a different central wavevector (and/or frequency). The