Effect of pump power on gain and saturation of doubleclad fiber amplifiers

Designing and fabrication of a continuous wave double–clad oscillator–amplifier array was carried out in orderto measure the small–signal gain and saturation power. In the array, the low power fiber laser seed signal at 1082.5nm is amplified through the single–mode double–clad ytterbium–doped silica fiber amplifier. The gain and saturation parameterscan be determined using the steady–state amplification relation. It is shown that those parameters increase at stronger pump powers of the amplifier mainly due to the dominant effect of the overlapping factor