Universal few-body physics and cluster formation

  title={Universal few-body physics and cluster formation},
  author={Chris H. Greene and P. Giannakeas and Jes{\'u}s P{\'e}rez-R{\'i}os},
  journal={Reviews of Modern Physics},
A comprehensive account of the theoretical analyses of the Efimov effect and the universal properties of three-body bound states is provided. Recent experimental studies are reviewed and shown how the few-body analysis also yields insights into many-body phenomena, accessible by the experimental ability to tune the range and strength of the forces between cold atoms. 

Four-Body Scale in Universal Few-Boson Systems.

It is found that at next-to-leading order (NLO) a four-body force is needed to obtain renormalized results for binding energies, and with the associated parameter fixed to the binding energy of the four-boson system, this force is shown to renormalize the five- and six-body systems as well.

Window for Efimov physics for few-body systems with finite-range interactions

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Universal temperature dependence of the ion-neutral-neutral three-body recombination rate

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Efimov Physics in Quenched Unitary Bose Gases.

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Ultracold Heteronuclear Three-Body Systems: How Diabaticity Limits the Universality of Recombination into Shallow Dimers.

The mass-imbalanced three-body recombination process that forms a shallow dimer is shown to possess a rich Efimov-Stückelberg landscape, with corresponding spectra that differ fundamentally from the

Precision Test of the Limits to Universality in Few-Body Physics.

A refined multichannel three-body model, built on the measurement of two-body physics, can account for this difference and even successfully predict the Efimov inelasticity parameter η.



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We address the microscopic origin of the universal three-body parameter that fixes the spectrum of few-atom systems in the Efimov regime. We identify it with a nonadiabatic deformation of the

Evidence for universal four-body states tied to an Efimov trimer.

The results obtained with an ultracold sample of cesium atoms at negative scattering lengths show a resonant enhancement of losses and provide strong evidence for the existence of a pair of four-body states, which is strictly connected to Efimov trimers via universal relations.

Origin of the three-body parameter universality in Efimov physics.

This study shows that the three-body parameter universality emerges because a universal effective barrier in theThree-body potentials prevents the three particles from simultaneously getting close together, and shows limitations on this universality.

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Microscopic origin and universality classes of the Efimov three-body parameter.

The low-energy spectrum of three particles interacting via nearly resonant two-body interactions in the Efimov regime is set by the so-called three-body parameter. We show that the three-body

Efimov physics and the three-body parameter within a two-channel framework

We calculate shallow three-body bound states in the universal regime, defined by Efimov, with inclusion of both scattering length and effective range parameters. The universal spectrum is recovered

Universal aspects of Efimov states and light halo nuclei

The parametric region in the plane defined by the ratios of the energies of the subsystems and the three-body ground state, in which Efimov states can exist, is determined. We use a renormalizable

Resonant five-body recombination in an ultracold gas of bosonic atoms

We combine theory and experiment to investigate five-body recombination in an ultracold gas of atomic cesium at negative scattering length. A refined theoretical model, in combination with extensive