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arXiv · 0806.3062

Dimer-dimer collisions at finite energies in two-component Fermi gases

J. P. D'Incao·Seth T. Rittenhouse·N. P. Mehta·Chris H. Greene
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Abstract

We introduce a major theoretical generalization of existing techniques for handling the three-body problem that accurately describes the interactions among four fermionic atoms. Application to a two-component Fermi gas accurately determines dimer-dimer scattering parameters at finite energies and can give deeper insight into the corresponding many-body phenomena. To account for finite temperature effects, we calculate the energy-dependent complex dimer-dimer scattering length, which includes contributions from elastic and inelastic collisions. Our results indicate that strong finite-energy effects and dimer dissociation are crucial for understanding the physics in the strongly interacting regime for typical experimental conditions. While our results for dimer-dimer relaxation are consistent with experiment, they confirm only partially a previously published theoretical result.

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J. P. D'Incao, Seth T. Rittenhouse, N. P. Mehta, Chris H. Greene. 2008-06-18. Dimer-dimer collisions at finite energies in two-component Fermi gases. https://doi.org/10.1103/physreva.79.030501

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