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: Paul S. Julienne (Assoc)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 26 - 50 of 391

Radiofrequency dressing of multiple Feshbach resonances

November 3, 2009
Author(s)
A M. Kaufman, R P. Anderson, Thomas Hanna, Eite Tiesinga, Paul S. Julienne, D S. Hall
We demonstrate and explain the coupling of several proximate Feshbach resonances in $^87}$Rb using radiofrequency (rf) radiation. We present accurate measurements of the resonances and observe the changes in the scattering properties that arise through the

Radiofrequency dressing of multiple Feshbach resonances

November 3, 2009
Author(s)
A M. Kaufman, R P. Anderson, Thomas Hanna, Eite Tiesinga, Paul S. Julienne, D S. Hall
We demonstrate and explain the coupling of several proximate Feshbach resonances in $^87}$Rb using radiofrequency (rf) radiation. We present accurate measurements of the resonances and observe the changes in the scattering properties that arise through the

Collisional cooling of ultra-cold atom ensembles using Feshbach resonances

September 8, 2009
Author(s)
Ludwig G. Mathey, Eite Tiesinga, Paul S. Julienne, Charles W. Clark
We propose a new type of cooling mechanism for ultra-cold fermionic atom ensembles, which capitalizes on the energy dependence of inelastic collisions in the presence of a Feshbach resonance. We first discuss the case of a single magnetic resonance, and

Multi-channel modeling of the formation of vibrationally cold polar KRb molecules.

May 14, 2009
Author(s)
Svetlana Kotochigova, Eite Tiesinga, Paul S. Julienne
We describe the theoretical advances that influenced the experimental creation of vibrationally and translationally cold polar 40K87Rb molecules [Nature Phys. 4, 622 (2008), Science 322, 231 (2008)]. Cold molecules were created from very-weakly bound

Prediction of Feshbach resonances from three input parameters

April 30, 2009
Author(s)
Thomas M. Hanna, Eite Tiesinga, Paul S. Julienne
We have developed a model of Feshbach resonances in gases of ultracold alkali metal atoms using the ideas of quantum defect theory. Our model requires just three parameters - the singlet and triplet scattering lengths, and the coefficient of the long range

Probing interactions between ultracold fermions

April 17, 2009
Author(s)
G K. Campbell, M M. Boyd, J W. Thomsen, M J. Martin, S Blatt, M D. Swallows, Travis L. Nicholson, Tara Fortier, Christopher W. Oates, Scott Diddams, Nathan D. Lemke, Pascal Naidon, Paul S. Julienne, Jun Ye, Andrew Ludlow
At ultracold temperatures, the Pauli exclusion principle suppresses collisions between identical fermions. This has motivated the development of atomic clocks using fermionic isotopes. However, by probing an optical clock transition with thousands of

Avoided crossings between bound states of ultracold Cesium dimers

November 5, 2008
Author(s)
Jeremy M. Hutson, Eite Tiesinga, Paul S. Julienne
We present a new computational method for calculating bound states of ultracold alkali metal dimers in the presence of magnetic fields. The new method is based on propagation of coupled differential equations and does not use a basis set for the

Comment on 'Laterally Squeezed Excitonic Wave Function in Quantum Wires'

October 16, 2008
Author(s)
Garnett W. Bryant, Y B. Band, Paul S. Julienne
Recent magnetophotoluminescence data on T-shaped quantum wires is reinterpreted based on a detailed theory of magnetoexcitons in T-shaped quantum wires. We show that the previous analysis greatly overestimates exciton squeezing in T-shaped wires.

Really Cool Molecules

October 16, 2008
Author(s)
Paul S. Julienne
Ultracold molecules have been made by applying a time-dependent magnetic field to a dilute quantum gas of ultracold trapped fermionic atoms. This raises the prospect of creating novel superfluids and molecular Bose-Einstein condensates.

Two-Body Transients in Coupled Atomic-Molecular BECs

March 3, 2008
Author(s)
Pascal Naidon, Eite Tiesinga, Paul S. Julienne
We discuss the dynamics of an atomic Bose-Einstein condensate when pairs of atoms are converted into molecules by single-color photoassociation. Three main regimes are found and it is shown that they can be understood on the basis oftime-dependent two-body

Effective-Range Description of a Bose Gas Under Strong Confinement

January 29, 2007
Author(s)
Pascal Naidon, Eite Tiesinga, William F. Mitchell, Paul S. Julienne
We point out in this paper that previous theories describing s-wave collisions of atomic bosons confined in 1D or 2D geometries can be extended to much tighter confinements by simply replacing the scattering length by the effective energy-dependent

Stationary Phase Approximation for the Strength of Optical Feshbach Resonances

August 7, 2006
Author(s)
R Ciurylo, Eite Tiesinga, Paul S. Julienne
Analytic expressions for the width and shift of a photoassociative resonance or an optically induced Feshbach resonance in ultra-cold collisions are derived using the quasi-classical stationary phase approximation. This approach is applicable over a wider