  Transitions to immeasurably small electrical resistance in thin films of
Ag/Au nanostructure-based films have generated significant interest because
such transitions can occur even at ambient temperature and pressure. While the
zero-bias resistance and magnetic transition in these films have been reported
recently, the non-equilibrium current-voltage ($I-V$) transport characteristics
at the transition remains unexplored. Here we report the $I-V$ characteristics
at zero magnetic field of a prototypical Ag/Au nanocluster film close to its
resistivity transition at the critical temperature $T_{C}$ of $\approx160$ K.
The $I-V$ characteristics become strongly hysteretic close to the transition
and exhibit a temperature-dependent critical current scale beyond which the
resistance increases rapidly. Intriguingly, the non-equilibrium transport
regime consists of a series of nearly equispaced resistance steps when the
drive current exceeds the critical current. We have discussed the similarity of
these observations with resistive transitions in ultra-thin superconducting
wires via phase slip centres.
