The present invention relates to a cascaded optical amplifier system having at least two optical amplifying stages with two pulsed pump sources provided and two amplifying media, the first of which receives the injection and at least one pump signal wherein the injection pulsed signal is amplified to a first power and energy lever. The second amplifying medium, optically coupled to the first, amplifies the first level signal to a second level amplified, injection pulsed signal. The duty cycle of the injection pulsed signal is synchronized with the first and second pulsed pump signals with the first pulsed pump signal having a different duration in the duty cycle than the second pulsed pump signal.
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