English

A Mixture of Bose and Fermi Superfluids

Quantum Gases 2016-09-15 v2

Abstract

Superconductivity and superfluidity of fermionic and bosonic systems are remarkable many-body quantum phenomena. In liquid helium and dilute gases, Bose and Fermi superfluidity has been observed separately, but producing a mixture in which both the fermionic and the bosonic components are superfluid is challenging. Here we report on the observation of such a mixture with dilute gases of two Lithium isotopes, 6Li and 7Li. We probe the collective dynamics of this system by exciting center-of-mass oscillations that exhibit extremely low damping below a certain critical velocity. Using high precision spectroscopy of these modes we observe coherent energy exchange and measure the coupling between the two superfluids. Our observations can be captured theoretically using a sum-rule approach that we interpret in terms of two coupled oscillators.

Keywords

Cite

@article{arxiv.1404.2548,
  title  = {A Mixture of Bose and Fermi Superfluids},
  author = {Igor Ferrier-Barbut and Marion Delehaye and Sebastien Laurent and Andrew T. Grier and Matthieu Pierce and Benno S. Rem and Frédéric Chevy and Christophe Salomon},
  journal= {arXiv preprint arXiv:1404.2548},
  year   = {2016}
}