Transient gain dynamics in saturated counter-pumped Raman amplifiers

Transient gain dynamics in doped-fiber amplifiers have been studied intensively in connection with sudden channel addition or removal caused by either unintentional failures, or by deliberate network reconfigurations. The main concern here is in the duration of the power transients, which may induce temporary performance degradation, and the amount of power surges, which may damage the optical components and cause system disruption. In this paper, we show that the gain dynamics are completely determined by the time behavior of a single state variable, namely the relative pump change sensed by the signals.