Article,
Internal motion within pulsating pure-quartic soliton molecules in a fiber laser
Affiliations
- [1] Tech Univ Denmark, Dept Elect & Photon Engn, DTU Electro, DK-2800 Lyngby, Denmark [NORA names: DTU Technical University of Denmark; University; Denmark; Europe, EU; Nordic; OECD];
- [2] Chinese Univ Hong Kong, Dept Mech & Automat Engn, Hong Kong, Peoples R China [NORA names: China; Asia, East];
- [3] Hebei Univ Technol, Ctr Adv Laser Technol, Tianjin 300401, Peoples R China [NORA names: China; Asia, East];
- [4] Harbin Engn Univ, Coll Phys & Optoelect Engn, Key Lab Infiber Integrated Opt, Minist Educ, Harbin 150001, Peoples R China [NORA names: China; Asia, East];
- [5] Qingdao Innovat & Dev Ctr Harbin Engn Univ, Qingdao 266000, Peoples R China [NORA names: China; Asia, East];
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Abstract
Various striking nonlinear evolution dynamics have been observed in mode-locked fiber lasers owing to the high peak power of the solitons. Herein, we numerically demonstrate the dynamical generation of dispersiondependent pure-quartic solitons (PQS) molecules in a fiber laser. We discover the evolution from a singlepulse initial condition to different types of pulsating PQS molecules with enhanced net fourth-order dispersion, indicating that the internal motion and energy exchange can be both quasi-periodical and periodical. Furthermore, we reveal that the generation of these two types of pulsating PQS molecules is associated with a gain competition effect between the two sub pulses during mode-locking. Finally, we propose a new method that can achieve the transition between a loose PQS molecule and a tight PQS molecule. Enlightened by the numerical results, we speculate that more internal motion within the PQS molecule will be discovered, which will promote a deep insight into the physical mechanism behind.