  We investigate the properties of the metallic state obtained by photo-doping
carriers into a Mott insulator. In a strongly interacting system, these
carriers have a long life-time, so that they can dissipate their kinetic energy
to a phonon bath. In the relaxed state, the scattering rate saturates at a
non-zero temperature-independent value, and the momentum-resolved spectral
function features broad bands which differ from the well-defined quasi-particle
bands of a chemically doped system. Our results indicate that a photo-doped
Mott insulator behaves as a bad metal, in which strong scattering between
doublons and holes inhibits Fermi-liquid behavior down to low temperature.
