English

Observation of a Strong Atom-Dimer Attraction in a Mass-Imbalanced Fermi-Fermi Mixture

Quantum Gases 2014-03-05 v3

Abstract

We investigate a mixture of ultracold fermionic 40^{40}K atoms and weakly bound 6^{6}Li40^{40}K dimers on the repulsive side of a heteronuclear atomic Feshbach resonance. By radio-frequency spectroscopy we demonstrate that the normally repulsive atom-dimer interaction is turned into a strong attraction. The phenomenon can be understood as a three-body effect in which two heavy 40^{40}K fermions exchange the light 6^{6}Li atom, leading to attraction in odd partial-wave channels (mainly p-wave). Our observations show that mass imbalance in a fermionic system can profoundly change the character of interactions as compared to the well-established mass-balanced case.

Keywords

Cite

@article{arxiv.1311.5146,
  title  = {Observation of a Strong Atom-Dimer Attraction in a Mass-Imbalanced Fermi-Fermi Mixture},
  author = {Michael Jag and Matteo Zaccanti and Marko Cetina and Rianne S. Lous and Florian Schreck and Rudolf Grimm and Dmitry S. Petrov and Jesper Levinsen},
  journal= {arXiv preprint arXiv:1311.5146},
  year   = {2014}
}