Recombination in the universal four-fermion system

In the systems of spin 12 fermions with resonant S-wave interactions supporting only weakly bound dimers the antisymmetry forbids recombination of three (or more) fermions at zero energy. However, the fermion-fermion-dimer recombination is only partially suppressed. It is studied in the framework of...

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Bibliographic Details
Main Author: A. Deltuva
Format: Article
Language:English
Published: Elsevier 2021-09-01
Series:Physics Letters B
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0370269321005396
Description
Summary:In the systems of spin 12 fermions with resonant S-wave interactions supporting only weakly bound dimers the antisymmetry forbids recombination of three (or more) fermions at zero energy. However, the fermion-fermion-dimer recombination is only partially suppressed. It is studied in the framework of momentum-space integral equations for the four-particle transition operators. In the vicinity of the unitary limit the fermion-fermion-dimer recombination rate, rescaled to build dimensionless quantity, is found to be linear in the effective range parameter, enabling a simple and accurate parametrization as well as evaluation of finite-range effects for any potential model. This feature makes the present results very useful in benchmarking different methods for three-cluster breakup and recombination calculations in four-particle systems. The interplay of the three-fermion and fermion-fermion-dimer recombination processes and their consequences for ultracold mixtures of fermions and dimers is discussed.
ISSN:0370-2693