Fig. 1. (a) Experimental setup; (b) measured output power at port 1; (c) measured spectral profile at port 1

Fig. 2. (a) Variation of pulse width at port 5 after amplifying with pump power of LD1; measured (b) spectra and phase curves, (c) FROG traces and (d) spectra and phase curves when pump power of LD1 is 170, 200, 310 mW; (e) measured frequency spectra when pump power of LD1 is 170, 200 and 310 mW at port 1

Fig. 3. (a) Repetition frequency fluctuation curve and Allan variance when laser is unlocked; (b) repetition frequency fluctuation curve Allan variance when laser is locked

Fig. 4. (a) SSB phase noise measured at port 5 when the repetition rate of the laser is free-running (black line) or locked (red line); (b) the integrated phase noise measured at port 5 when the repetition rate of the laser is free-running (black line) or locked (red line)