Fig. 1. Evolution of DSR pulse with increase of gain^[27]. (a) Time domain; (b) frequency domain

Fig. 2. Schematic of experimental device based on NPR mode locking^[26]

Fig. 3. Schematic of experimental device based on NOLM mode locking^[41]

Fig. 4. Schematic of experimental device based on NALM mode locking^[32]

Fig. 5. Evolutions of two kinds of anti-DSR phenomena in time domain and frequency domain^[41]. (a) Pulse splitting, time domain; (b) pulse splitting, frequency domain; (c) pulse anomalous shrinkage, time domain; (d) pulse anomalous shrinkage, frequency domain

Fig. 6. Different period doubling modes^[69]

Fig. 7. Simulated results of pulse shrinkage phenomenon of DSR. (a) Filter positions and shapes at different gains；(b) evolution of DSR pulse shrinkage in time domain; (c) pulse duration versus gain

Fig. 8. Simulated results of pulse shrinkage phenomenon of DSR in period doubling state. (a) Filter positions and shapes at different gains; (b) typical period doubling state; (c) pulse duration versus gain

Fig. 9. Evolutions of left-tilt DSR pulse observed in experiment in time domain and frequency domain^[71]. (a) Time domain; (b) frequency domain

Fig. 10. Comparison of spectral shapes^[71]. (a) Spectral shape used for simulation of normal DSR; (b) spectral shapes used for simulation of tilt-top DSR pulse; (c) spectra of left-tilt DSR; (d) spectra of right-tilt DSR