Atom-dimer scattering and long-lived trimers in fermionic mixtures

J. Levinsen 1, T. G. Tiecke 2, J. T. M. Walraven 2, D. S. Petrov 1, 3

Physical Review Letters 103 (2009) 153202

We consider a heteronuclear fermionic mixture on the molecular side of an interspecies Feshbach resonance and discuss atom-dimer scattering properties in uniform space and in the presence of an external confining potential, restricting the system to a quasi-2D geometry. We find that there is a peculiar atom-dimer p-wave resonance which can be tuned by changing the frequency of the confinement. Our results have implications for the ongoing experiments on Lithium-Potassium mixtures, where this mechanism allows for switching the p-wave interaction between a K atom and Li-K dimer from attractive to repulsive, and forming a weakly bound trimer with unit angular momentum. We show that such trimers are long-lived and the atom-dimer resonance does not enhance inelastic relaxation in the mixture, making it an outstanding candidate for studies of p-wave resonance effects in a many-body system.

  • 1. Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS),
    CNRS : UMR8626 – Université Paris XI - Paris Sud
  • 2. Van der Waals-Zeeman Institute,
    University of Amsterdam
  • 3. National Research Centre "Kurchatov Institute" (NRC KI),
    University of Moscow