title: Symmetric and asymmetric optical multipeak solitons on a continuous wave background in the femtosecond regime.
abstract: We study symmetric and asymmetric optical multipeak solitons on a continuous wave background in the femtosecond regime of a single-mode fiber. Key characteristics of such multipeak solitons, such as the formation mechanism, propagation stability, and shape-changing collisions, are revealed in detail. Our results show that this multipeak (symmetric or asymmetric) mode could be regarded as a single pulse formed by a nonlinear superposition of a periodic wave and a single-peak (W-shaped or antidark) soliton. In particular, a phase diagram for different types of nonlinear excitations on a continuous wave background, including the unusual multipeak soliton, the W-shaped soliton, the antidark soliton, the periodic wave, and the known breather rogue wave, is established based on the explicit link between exact solution and modulation instability analysis. Numerical simulations are performed to confirm the propagation stability of the multipeak solitons with symmetric and asymmetric structures. Further, we unveil a remarkable shape-changing feature of asymmetric multipeak solitons. It is interesting that these shape-changing interactions occur not only in the intraspecific collision (soliton mutual collision) but also in the interspecific interaction (soliton-breather interaction). Our results demonstrate that each multipeak soliton exhibits the coexistence of shape change and conservation of the localized energy of a light pulse against the continuous wave background.
authors.affiliation: School of Physics, Northwest University, Xi'an 710069, China.|Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi'an 710069, China.
authors.forename: Chong
authors.initials: C
authors.lastname: Liu
authors.affiliation: School of Physics, Northwest University, Xi'an 710069, China.|Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi'an 710069, China.
authors.forename: Zhan-Ying
authors.initials: ZY
authors.lastname: Yang
authors.affiliation: School of Physics, Northwest University, Xi'an 710069, China.|Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi'an 710069, China.
authors.forename: Li-Chen
authors.initials: LC
authors.lastname: Zhao
authors.affiliation: School of Physics, Northwest University, Xi'an 710069, China.|Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi'an 710069, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Duan
authors.affiliation: Department of Physics, Shanxi Medical University, Taiyuan, Shanxi 030001, China.
authors.forename: Guangye
authors.initials: G
authors.lastname: Yang
authors.affiliation: Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi'an 710069, China.|Institute of Modern Physics, Northwest University, Xi'an 710069, China.
authors.forename: Wen-Li
authors.initials: WL
authors.lastname: Yang