Fig. 1. Schematic diagram of passive mode-locked laser. WDM: wavelength division multiplexer; EDF: erbium-doped fiber; OC: 10∶90 optical coupler; PC1 and PC2: polarization controller; PD-ISO: polarization dependent isolator; SMF: single-mode fiber; DCF: dispersion compensation fiber; EDFA: erbium-doped fiber amplifier; HNLF: high nonlinear fiber; OSA: optical spectrum analyzer; OSC: oscilloscope

Fig. 2. (a) Structure diagram of tapered optical fiber; (b) Physical drawing of tapered HNLF

Fig. 3. Mode-locked laser operates in the normal dispersion region. (a) Optical spectrum; (b) Time-domain diagram; (c) RF spectrum, insert (range of RF spectrum in 300 MHz); (d) Autocorrelation trace of pulse (black point), Sech² fit (red curve)

Fig. 4. (a) Time-domain diagram; (b) Autocorrelation trace of dissipative soliton in 11 m single-mode fiber

Fig. 5. (a) Evolution of DS spectrum; (b) Time-domain diagram; (c) RF spectrum, insert (0-300 MHz span range of PF spectrum); (d) Autocorrelation trace of evolution pulse (black), Gaussian fit (red)

Fig. 6. (a) Evolution of optical spectrum with pump power; (b) Autocorrelation trace at the pump power of 1 W; (c) Comparison of pump1 power vs output power between DS and wave-free breaking pulse; (d) Comparing between maximum lock-mode pump power, optical conversion efficiency, pulse width, pulse energy, peak power for DS and wave-free breaking pulse

Fig. 7. Evolution of supercontinuum with the increasing of pump power. (a) Supercontinuum generated by dissipative soliton; (b) Supercontinuum generated by wave-free breaking pulse