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Search Publications by: Paul S. Julienne (Assoc)

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Displaying 1 - 25 of 213

A Two-Channel R-Matrix Analysis of Magnetic Field Induced Feshbach Resonances

October 12, 2021
Author(s)
N Nygaard, Barry I. Schneider, Paul S. Julienne
A Feshbach resonance arises in cold atom scattering due to the complex interplay between several coupled channels. However, the essential physics of the resonance may be encapsulated in a simplified model consisting of just two coupled channels. In this

Cruising Through Molecular Bound-State-Manifolds With Radio-Frequency

October 12, 2021
Author(s)
F Lang, P Van der Straten, B Brandstatter, G Thalhammer, K Winkler, Paul S. Julienne, R Grimm, J Hecker Denschlag
The emerging field of ultracold molecules with their rich internal structure is currently attracting a lot of interest. Various methods have been developed to produce ultracold molecules in pre-set quantum states. For future experiments it will be

Excited Thomas-Efimov Levels in Ultracold Gases

October 12, 2021
Author(s)
M D. Lee, T Koehler, Paul S. Julienne
Since the early days of quantum physics, the complex behavior of three interacting particles has been the subject of numerous experimental and theoretical studies. In a recent Letter to Nature, Kraemer et al. [Nature (London) 440, 315 (2006)] report on

Molecular Production in Two Component Atomic Fermi Gases

October 12, 2021
Author(s)
J Chwedenczuk, K Goral, T K hler, Paul S. Julienne
We provide a practical approach to the molecular production via linear downward sweeps of Feshbach resonances in degenerate Fermi gases containing incoherent mixtures of two atomic spin states. We show that the efficiency of the association of atoms is

Production of Cold Molecules via Magnetically Tunable Feshbach Resonances

October 12, 2021
Author(s)
T Koehler, K Goral, Paul S. Julienne
Magnetically tunable Feshbach resonances were employed to associate cold diatomic molecules in a series of experiments involving both atomic Bose as well as two spin component Fermi gases. This review illustrates theoretical concepts of both the particular

Quantum Logic via the Exchange Blockade in Ultracold Collisions

October 12, 2021
Author(s)
D Hayes, Paul S. Julienne, I H. Deutsch
A nuclear spin can act as a quantum switch that turns on or off ultracold collisions between atoms even when there is neither interaction between nuclear spins nor between the nuclear and electron spins. This exchange blockade is a new mechanism for

Radio-Frequency Output Coupling of the Bose-Einstein Condensate in Atom Lasers

October 12, 2021
Author(s)
Y B. Band, Paul S. Julienne, M Trippenbach
Experiments have conclusively demonstrated coherence properties of Bose-Einstein condensates [BECs] [1] and the radio-frequency [rf] radiation output coupling of BE condensates [2]. Hence, the concept of an atom laser [3 9] based upon a BEC that is output

Ultra-Cold Collisions of Atoms and Molecules

February 19, 2017
Author(s)
Paul S. Julienne
The study of collisions of neutral atoms and molecules at ultralow collision energies is made possible by advances in techniques for cooling and trapping such species. Excellent reviews of laser cooling of atoms are given in the Nobel Lectures of Chu 2

Hyperfine structure of weakly bound levels in the lowest 1g state of molecular 87Rb2

November 13, 2013
Author(s)
Chin-Chun Tsai, T Bergeman, Eite Tiesinga, Paul S. Julienne, D J. Heinzen
Photoassociation resonances in the 87Rb2 1g state dissociating to 52S+52P1/2 were produced by the excitation of colliding 87Rb atoms in a far-off resonance (FORT) trap. Levels down to 31 cm−1 below the dissociation limit were measured with resonance

Resonant control of polar molecules in an optical lattice

February 1, 2012
Author(s)
Thomas M. Hanna, Eite Tiesinga, William F. Mitchell, Paul S. Julienne
We study the resonant control of two nonreactive polar molecules in an optical lattice site, focussing on the example of RbCs. Collisional control can be achieved by tuning bound states of the intermolecular dipolar potential, by varying the applied

Spatial separation in a thermal mixture of ultracold174Yb and 87Rb atoms

April 21, 2011
Author(s)
F. Baumer, F. Munchow, A. Gorlitz, Stephen Maxwell, Paul S. Julienne, Eite Tiesinga
We report on the observation of unusually strong interactions in a thermal mixture of ultracold atoms which cause a significant modification of the spatial distribution. A mixture of 87Rb and 174Yb with a temperature of a few μK is prepared in a hybrid

Creation and manipulation of Feshbach resonances with radio-frequency radiation

August 12, 2010
Author(s)
Thomas M. Hanna, Eite Tiesinga, Paul S. Julienne
We present a simple technique for studying collisions of ultracold atoms in the presence of a magnetic field and radio-frequency radiation (rf ). Resonant control of scattering properties can be achieved by using rf to couple a colliding pair of atoms to a

Feshbach resonances in ultracold gases

April 29, 2010
Author(s)
Chin P. Cheng, R Grimm, Paul S. Julienne, Eite Tiesinga
Feshbach resonances are the essential tool to control the interaction between atoms in ultracold quantum gases. They have found manifold experimental applications, opening up the way to important breakthroughs. This Review gives a broad coverage of 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

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.