[1] Dong Z K, Song Y R. Research progress of mode-locked fiber lasers based on saturable absorbers[J]. Chinese Journal of Lasers, 48, 0501006(2021).

[2] Lezius M, Wilken T, Deutsch C et al. Space-borne frequency comb metrology[J]. Optica, 3, 1381-1387(2016).

[3] Xu C, Wise F W. Recent advances in fibre lasers for nonlinear microscopy[J]. Nature Photonics, 7, 875-882(2013).

[4] Du Y S, Yuan S, Wang Y et al. 706 MHz high repetition rate femtosecond Yb-doped fiber laser[J]. Laser & Optoelectronics Progress, 58, 0914004(2021).

[5] Fan M Q, Xia H D, Xu D P et al. Research progress of new regime mode-locked fiber lasers and amplification and compression technologies[J]. Laser & Optoelectronics Progress, 58, 0300003(2021).

[6] Dai L L, Zou C H, Huang Q Q et al. Continuously tunable mode-locked fiber laser based on tilted fiber grating[J]. Chinese Journal of Lasers, 46, 0508026(2019).

[7] Han D D, Hui Z Q, Xie J H et al. Single-shot observation of stretched-pulse buildup dynamics in an ultrafast fiber laser[J]. Infrared Physics & Technology, 102, 102984(2019).

[8] Ilday F O, Buckley J R, Clark W G et al. Self-similar evolution of parabolic pulses in a laser[J]. Physical Review Letters, 92, 213902(2004).

[9] Zhu X J, Geng J, Zhang G A et al. Tunable double pulse dissipative solitons Yb-doped fiber laser based on Sagnac loop[J]. Acta Optica Sinica, 39, 0414002(2019).

[10] Zhao L M, Tang D Y, Wu J. Gain-guided soliton in a positive group-dispersion fiber laser[J]. Optics Letters, 31, 1788-1790(2006).

[11] Wise F W, Chong A, Renninger W H. High-energy femtosecond fiber lasers based on pulse propagation at normal dispersion[J]. Laser & Photonics Review, 2, 58-73(2008).

[12] Grelu P, Akhmediev N. Dissipative solitons for mode-locked lasers[J]. Nature Photonics, 6, 84-92(2012).

[13] Han D D, Ren K L, Zheng Y P et al. Simultaneous generation and real-time observation of soliton molecules and singlets in an anomalous dispersion mode-locked fiber laser[J]. Optik, 242, 167312(2021).

[14] Tang D Y, Man W S, Tam H Y et al. Observation of bound states of solitons in a passively mode-locked fiber laser[J]. Physical Review A, 64, 033814(2001).

[15] Grelu P, Belhache F, Gutty F et al. Phase-locked soliton pairs in a stretched-pulse fiber laser[J]. Optics Letters, 27, 966-968(2002).

[16] Ortaç B, Hideur A, Brunel M et al. Generation of parabolic bound pulses from a Yb-fiber laser[J]. Optics Express, 14, 6075-6083(2006).

[17] Wang K J, Wang H, Du T J et al. Effect of intracavity filtering bandwidth on bound-state soliton generation in normal dispersion regime[J]. Chinese Journal of Lasers, 46, 0806004(2019).

[18] Gui L L, Wang P, Ding Y H et al. Soliton molecules and multisoliton states in ultrafast fibre lasers: intrinsic complexes in dissipative systems[J]. Applied Sciences, 8, 201(2018).

[19] Stratmann M, Pagel T, Mitschke F. Experimental observation of temporal soliton molecules[J]. Physical Review Letters, 95, 143902(2005).

[20] Pang M, He W, Jiang X et al. All-optical bit storage in a fibre laser by optomechanically bound states of solitons[J]. Nature Photonics, 10, 454-458(2016).

[21] Herink G, Kurtz F, Jalali B et al. Real-time spectral interferometry probes the internal dynamics of femtosecond soliton molecules[J]. Science, 356, 50-54(2017).

[22] Peng J S, Zeng H P. Build-up of dissipative optical soliton molecules via diverse soliton interactions[J]. Laser & Photonics Reviews, 12, 1800009(2018).

[23] Krupa K, Nithyanandan K, Andral U et al. Real-time observation of internal motion within ultrafast dissipative optical soliton molecules[J]. Physical Review Letters, 118, 243901(2017).

[24] Wang Z Q, Nithyanandan K, Coillet A et al. Optical soliton molecular complexes in a passively mode-locked fibre laser[J]. Nature Communications, 10, 830(2019).

[25] Liu M, Li H, Luo A P et al. Real-time visualization of soliton molecules with evolving behavior in an ultrafast fiber laser[J]. Journal of Optics, 20, 034010(2018).

[26] Zeng H P, Peng J S. Time-varying dynamics of mode-locked fiber lasers[J]. Acta Optica Sinica, 41, 0114005(2021).

[27] Agrawal G P[M]. Applications of nonlinear fiber optics(2001).