We theoretically investigate the pair-superfluid phase of two-component
ultracold gases with negative inter-species interactions in an optical lattice.
We establish the phase diagram for filling n=1 at zero and finite
temperature, by applying Bosonic Dynamical Mean-Field Theory, and confirm the
stability of pair-superfluidity for asymmetric hopping of the two species.
While the pair superfluid is found to be robust in the presence of a harmonic
trap, we observe that it is destroyed already by a small population imbalance
of the two species.Comment: 7 pages, 11 figure