  We examine the dynamics of a correlated quantum dot in the mixed valence
regime. We perform numerically exact calculations of the current after a
quantum quench from equilibrium by rapidly applying a bias voltage in a wide
range of initial temperatures. The current exhibits short equilibration times
and saturates upon the decrease of temperature at all times, indicating Kondo
behavior both in the transient regime and in steady state. The time-dependent
current saturation temperature matches the Kondo temperature at small times or
small voltages; a substantially increased value is observed outside of linear
response. These signatures are directly observable by experiments in the
time-domain.
