We investigate three-body recombination loss across a Feshbach resonance in a gas of ultracold ${}^7\mathrm{Li}$ atoms prepared in the absolute ground state and perform a comparison with previously reported results of a different nuclear-spin state [N. Gross et al., Phys. Rev. Lett. 103, 163202 (2009)]. We extend the previously reported universality in three-body recombination loss across a Feshbach resonance to the absolute ground state. We show that the positions and widths of recombination minima and Efimov resonances are identical for both states which indicates that the short-range physics is nuclear-spin independent.

• Received 25 March 2010

DOI:https://doi.org/10.1103/PhysRevLett.105.103203