Final-state effects in the radio frequency spectrum of strongly interacting fermions

We model the impact of final state interactions on the radio frequency spectrum of a strongly interacting two-component superfluid Fermi gas. In addition to a broad asymmetric peak coming from the break-up of Cooper pairs we find that, for appropriate parameters, one can observe a sharp symmetric "bound-bound" spectral line coming from the conversion of Cooper pairs in one channels to pairs/molecules in another.