Semianalytic theory of laser-assisted resonant cold collisions

Bohn, John L.; Julienne, Paul S.

doi:10.1103/physreva.60.414

Cited by 219 publications

(313 citation statements)

References 39 publications

Supporting

Mentioning

300

Contrasting

Order By: Relevance

“…Both numerical and analytic calculations, similar to those used in the Appendix of Ref. [16], show that the magnitude of the FranckCondon factor (ignoring an oscillating phase factor) increases as the binding energy of the excited level decreases. To operate at sufficiently large detuning to satisfy Eqs.…”

mentioning

confidence: 93%

“…We also require that |∆ − ∆ e | be much larger than other contributions to the width of the photoassociation line such as the thermal width, Doppler width [20], light induced shift [16,22], and the mean-field shift in the case of BEC [23].…”

mentioning

confidence: 99%

“…Optical Feshbach control can be also applied to other atomic systems having a similar electronic structure. The recent Bose-Einstein condensation of ytterbium [21] makes this system especially interesting.The theoretical description of optical Feshbach resonances and the closely related photoassociation (PA) process is well established [14,15,16]. The elastic and inelastic scattering rates due to a single photoassociation resonance level depends on (1) the natural line width Γ e,nat ≈ 2Γ A of the excited molecular level e, (2) the stimulated width Γ eg (ε r ) that couples the excited level to the s-wave collision of the ground state g at relative kinetic energy ε r , and (3) the detuning ∆ − ∆ e from optical resonance.…”

mentioning

confidence: 99%

“…These optical Feshbach resonances are theoretically analyzed in Refs. [15,16] and implemented experimentally in Refs. [17,18].…”

mentioning

confidence: 99%

See 3 more Smart Citations

Optical tuning of the scattering length of cold alkaline-earth-metal atoms

2005

View full text Add to dashboard Cite

It is possible to tune the scattering length for the collision of ultra-cold 1 S0 ground state alkaline-earth atoms using an optical Feshbach resonance. This is achieved with a laser far detuned from an excited molecular level near the frequency of the atomic intercombination 1 S0-3 P1 transition. Simple resonant scattering theory, illustrated by the example of 40 Ca, allows an estimate of the magnitude of the effect. Unlike alkali metal species, large changes of the scattering length are possible while atom loss remains small, because of the very narrow line width of the molecular photoassociation transition. This raises prospects for control of atomic interactions for a system without magnetically tunable Feshbach resonance levels.PACS numbers: 34.50. Rk, 34.10.+x, 32.80.Pj In recent years the ability to change the interaction between ultra-cold colliding atoms has opened the way for new and exciting experiments with ultra-cold atomic gases. The observation of a Bose-Einstein condensate (BEC) in atomic cesium [1] would have been impossible without the ability to change the interaction from being attractive to being repulsive. More impressively, time-varying interactions have allowed the creation of condensates of two-atom molecules starting from an atomic Bose condensate [2,3]. Most recently, the observation of the condensation of pairs of fermionic [4] atoms has started investigations into the so-called BEC-BCS crossover [5], where BCS is the abbreviation for the BardeenCooper-Schrieffer phase transition in a fermionic gas [6].The key to these developments has been the ability to change the interaction between atoms by a magnetically-tuned Feshbach resonance [7]. Theoretical discussion of the properties of these resonances can be found in Refs. [8,9,10,11]. The interaction between the atoms at ultra-cold temperature can be characterized by a single parameter, the scattering length [12,13], which can be controlled in sign and magnitude using these resonances.Another way to change the scattering length of two colliding atoms is to optically couple the ground scattering state with an excited bound state [14]. These optical Feshbach resonances are theoretically analyzed in Refs. [15,16] and implemented experimentally in Refs. [17,18]. The recent experiment of Theis et al. [18] with 87 Rb atoms showed, however, that a significant change of the scattering length is accompanied with substantial loss of atoms. The same is true if a twocolor Raman process is used [19].In this paper we discuss the optical tuning of scattering lengths in ultra-cold alkaline-earth atom vapors. To do so we will assume that the laser is far detuned from excited molecular states near the intercombination transition, 1 S 0 -3 P 1 , as recently analyzed in Ref. [20]. We show that significant changes of the scattering strength can be achieved without the excessive atom loss that plagues experiments with alkali-metal gases [18]. Prospects for an optically tuned scattering length in ultra-cold alkaline-earth vapors seems to be particularly a...

show abstract

mentioning

confidence: 93%

mentioning

confidence: 99%

mentioning

confidence: 99%

“…These optical Feshbach resonances are theoretically analyzed in Refs. [15,16] and implemented experimentally in Refs. [17,18].…”

mentioning

confidence: 99%

See 2 more Smart Citations

Optical tuning of the scattering length of cold alkaline-earth-metal atoms

2005

View full text Add to dashboard Cite

show abstract

“…This sudden increase of the inelastic transition rates can be reproduced semiquantitatively by applying the distorted wave Born approximation (DWBA) [22], as has been successfully done for the magnetic dipolar interaction of cold alkali atoms [10,11] as well as in a number of problems in cold collisions [25,26]. The first order DWBA is a simple two state perturbation approximation applicable in cases where inelastic scattering is weak in comparison with elastic scattering.…”

Section: A Magnetic Field Dependencementioning

confidence: 99%

Magnetic-field effects in ultracold molecular collisions

Volpi

Bohn

2002

Phys. Rev. A

Self Cite

View full text Add to dashboard Cite

We investigate the collisional stability of magnetically trapped ultracold molecules, taking into account the influence of magnetic fields. We compute elastic and spin-state-changing inelastic rate constants for collisions of the prototype molecule 17 O 2 with a 3 He buffer gas as a function of the magnetic field and the translational collision energy. We find that spin-state-changing collisions are suppressed by Wigner's threshold laws as long as the asymptotic Zeeman splitting between incident and final states does not exceed the height of the centrifugal barrier in the exit channel. In addition, we propose a useful one-parameter fitting formula that describes the threshold behavior of the inelastic rates as a function of the field and collision energy. Results show a semi-quantitative agreement of this formula with the full quantum calculations, and suggest useful applications also to different systems. As an example, we predict the low-energy rate constants relevant to evaporative cooling of molecular oxygen.

show abstract

Production of RbCs Molecules in the Rovibronic Ground State via Short‐Range Photoassociation to the 2 ¹Π₁, 2 ³Π₁, and 3 ³Σ States

2016

View full text Add to dashboard Cite

We report the production of ultracold Rb Cs molecules in their rovibronic ground state X Σ (v=0; J=0), by short-range photoassociation (PA) to the 2 Π , 2 Π , and 3 Σ1+ states. In the PA frequency range from 11650 to 12150 cm (corresponding to energy levels 15500-16000 cm above the bottom of the X potential), we have observed 40 sets of new PA lines. For selected PA states, we investigate vibrational branching, rotational branching, and saturation behavior. Among these 40 new PA lines, the 3 Σ1+ (v=3) state has the highest molecule production rate of 2 x 10 molecules s into the rovibronic ground state.

show abstract

Semianalytic theory of laser-assisted resonant cold collisions

Cited by 219 publications

References 39 publications

Optical tuning of the scattering length of cold alkaline-earth-metal atoms

Optical tuning of the scattering length of cold alkaline-earth-metal atoms

Magnetic-field effects in ultracold molecular collisions

Production of RbCs Molecules in the Rovibronic Ground State via Short‐Range Photoassociation to the 2 ¹Π₁, 2 ³Π₁, and 3 ³Σ States

Contact Info

Product

Resources

About

Semianalytic theory of laser-assisted resonant cold collisions

Cited by 219 publications

References 39 publications

Optical tuning of the scattering length of cold alkaline-earth-metal atoms

Optical tuning of the scattering length of cold alkaline-earth-metal atoms

Magnetic-field effects in ultracold molecular collisions

Production of RbCs Molecules in the Rovibronic Ground State via Short‐Range Photoassociation to the 2 1Π1, 2 3Π1, and 3 3Σ States

Contact Info

Product

Resources

About

Production of RbCs Molecules in the Rovibronic Ground State via Short‐Range Photoassociation to the 2 ¹Π₁, 2 ³Π₁, and 3 ³Σ States