1307.5153 (G. Zürn et al.)

Pairing in few-fermion systems with attractive interactions    [PDF]

G. Zürn, A. N. Wenz, S. Murmann, T. Lompe, S. Jochim

We have studied quasi one-dimensional few-particle systems consisting of one to six ultracold fermionic atoms in two different spin states with attractive interactions. We probe the system by deforming the trapping potential and by observing the tunneling of particles out of the trap. For even particle numbers we observe a tunneling behavior which deviates from uncorrelated single-particle tunneling indicating the existence of pair correlations in the system. From the tunneling timescales of the systems we infer the single particle dissociation energies for different particle numbers which show a strong odd-even effect, similar to the one observed for neutron separation experiments in nuclei.

View original: http://arxiv.org/abs/1307.5153