Experimental study of the amplification of femtosecond laser pulses in fiber amplifier

The Experimental results of amplification of 1.531 μm femtosecond laser pulses using Er3+-doped fiber amplifier were reported. The femtosecond pulses generated by a self-starting additive pulses mode-locked Er3 PLU fiber laser with pulse duration of 410 fs injected into the Er3+-doped fiber amplifier (6 m, high doping concentration Er3+-doped fiber), the maximum amplification gain of 55(17.4 dB) and 64.4 (18.1 dB) and the maximum single pulse energy (peak power) of 0.384 nJ(752 W) and 0.452 nJ(1295 W) have been obtained with forward and backward pumping respectively. The shortest output pulses duration are 501 fs and 309 fs with forward and backward pumping respectively.