Note: amplification characteristics of all-normal-dispersion mode-locked Yb-doped fiber laser: influence of input...

The amplification properties of the pulses at and after the nonlinear polarization rejection (NPR) port of an all-normal-dispersion Yb-doped mode-locked fiber laser are studied. The experimental results show that the spectra of the output pulses after the NPR port are considerably resistant to distortions on amplification and can be compressed in the femtosecond regime without any significant side-lobes and hence can serve as an excellent seed source for further power amplification. The experimental results are substantiated by numerical analysis of the amplifier setup.