Fig. 1. Evolution of pulse in optical fiber main amplifier. (a) When γ=0 and α=0, γ=3 and α=0, γ=3 and α=2, and γ=3 and α=4, pulse width changes with fiber length; (b) when fiber length is 2.5 m, 3.0 m, 3.5 m, and 4.0 m, pulse width changes with gain coefficient of fiber amplifier; (c) when fiber length (gain) is 2.5 m (24 dB), 3.5 m (18 dB), and 4.0 m (15 dB), the gain is 15 dB, pulse width changes with gain coefficient of fiber amplifier

Fig. 2. Schematic diagram of experimental device

Fig. 3. Experimental results. (a) Pulse spectrum output by single-mode fiber power amplifier (inset: autocorrelation curve); (b) partial autocorrelation curve of the sub-pulse train after 64 pulses are separated

Fig. 4. Experimental results. (a) Output spectrum and (b) autocorrelation curve of main amplifier under low non-linearity condition; (c) output spectrum and (d) autocorrelation curve of main amplifier under high non-linearity condition

Fig. 5. Experimental results. (a) Output spectrum of 778 nm pulse; (b) autocorrelation curve of 778 nm pulse; (c) power stability of 1560 nm pulse; (d) power stability of 778 nm pulse