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Search Publications by: Charles W Clark (Assoc)

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Displaying 101 - 125 of 225

Output Coupling from a Trapped Bose-Einstein Condensate in a Vortex State

August 1, 2003
Author(s)
P B. Blakie, R J. Ballagh, Charles W. Clark
We demonstrate how a topological atom laser can be realized by output coupling a trapped vortex state with a Raman scattering process. We find a linearized analytic solution from which a generalized resonance condition for Raman output coupling is

Microscopic Structure of a Vortex Line in a Dilute Superfluid Fermi Gas

May 1, 2003
Author(s)
N Nygaard, G M. Bruun, Charles W. Clark, D L. Feder
The microscopic properties of a single vortex in a dilute superfluid Fermi gas at zero temperature are examined within the framework of self-consistent Bogoliubov-de Gennes theory. Using only physical parameters as inputwe study the pair potential, the

Optimizing the Fast Rydberg Quantum Gate

April 1, 2003
Author(s)
M S. Safronova, Carl J. Williams, Charles W. Clark
The fast phase gate scheme, in which the qubits are atoms confined in sites of an optical lattice, and gate operations are mediated by excitation of Rydberg states, was proposed by Jaksch et al. Phys. Rev. Lett. 85, 2208 (2000). A potential source of

Bogoliubov Approach to Superfluidity of Atoms in an Optical Lattice

January 1, 2003
Author(s)
A M. Rey, Karen G. Burnett, R Roth, M Edwards, Carl J. Williams, Charles W. Clark
We use the Bogoliubov theory of atoms in an optical lattice to the study the approach to the Mott-insulator transition. We derive an explicit expression for the superfluid density based on the rigidity of the system under phase variations. This enables us

Linear Spin Waves in a Trapped Bose Gas

October 1, 2002
Author(s)
T Nikuni, J E. Williams, Charles W. Clark
An ultra-cold Bose gas of two level atoms can be thought of as a spin-1/2 Bose gas. It supports spin wave collective modes due to the exchange mean field. Such collective spin oscillations have been observed in recent experiments at JILA with 87Rb

Longitudinal Spin Waves in a Dilute Bose Gas

June 1, 2002
Author(s)
J E. Williams, T Nikuni, Charles W. Clark
We present a kinetic theory for a dilute noncondensed Bose gas of two-level atoms that predicts the transient spin segregation observed in a recent experiment. The underlying mechanism driving spin currents in the gas is due to a mean-field effect arising

The Bogoliubov Approach to Number Squeezing of Atoms in an Optical Lattice

April 1, 2002
Author(s)
K Burnett, M Edwards, Charles W. Clark, M Shotter
We describe an approach for finding the number squeezing for arrays of atoms in an optical lattice. It is based on a straightforward extension of the Bogoliubov method. We discuss the conditions for optimizing squeezing and how to predict what will be

Synchrotron Ultraviolet Radiation Facility SURF III

March 1, 2002
Author(s)
Uwe Arp, Charles W. Clark, Alex P. Farrell, E Fein, Mitchell L. Furst, Edward W. Hagley
The National Institute of Standards and Technology (NIST) has operated the Synchrotron Ultraviolet Radiation Facility (SURF) continuously since the early 1960s. The original accelerator was converted into a storage ring, called SURF II, in 1974. Then in

Consequence of Superfluidity on the Expansion of a Rotating Bose-Einstein Condensate

February 1, 2002
Author(s)
Mark A. Edwards, Charles W. Clark, P Pedri, L Pitaevskii, S Stringari
By solving the hydrodynamic equations of irrotational superfluids we investigate the time evolution of a rotating condensate expanding after the sudden release of the confining trap. If the condensate is initially rotating slowly its angular velocity is

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