The dynamic characteristics of pure-quartic solitons and soliton molecules

• Published in: Applied Mathematical Modelling Vol. 102; pp. 305 - 312
• Main Authors: Liu, Xiaoyan, Zhang, Hongxin, Liu, Wenjun
• Format: Journal Article
• Language: English
• Published: New York Elsevier Inc 01.02.2022; Elsevier BV
• Subjects: Bilinear forms; Dynamic characteristics; Fiber lasers; Hirota’s bilinear method; Laser mode locking; Molecular interactions; Optical communication; Optical fibers; Parameters; Pulse duration; Pure-quartic solitons; Schrodinger equation; Short pulses; Solitary waves; Soliton molecules; Hirota’s bilinear method; Soliton molecules; Pure-quartic solitons; Bilinear forms
• DOI: 10.1016/j.apm.2021.09.042
• ISSN: 0307-904X; 1088-8691

•The one- and two-PQS solutions of the fourth-order nonlinear Schrödinger equation are obtained.•The PQS molecules are obtained by using the velocity resonance conditions.•The interaction states of PQSs and PQS molecules are analyzed respectively.•It is found that PQS molecules will interact with each other to transfer like threesolitons under certain parameter.•By means of parameter control, the soliton-asymmetric soliton molecule is obtained. Pure-quartic solitons (PQSs) with higher energy in short pulse width have been generated in the mode-locked fiber laser recently, and soliton molecules have been found as a means to improve the communication capacity of the optical fiber, which has attracted much attention. In this paper, we consider the fourth-order nonlinear Schrödinger equation (FNLSE) derived from Lakshmanan-Porsezian-Daniel equation which is describing the propagation of PQS in optical fiber systems. Through the Hirota’s bilinear method, the bilinear forms and the one- and two-PQS solutions of the FNLSE are obtained. Then, the dynamic characteristics of the PQSs are discussed by using parameter control. Besides, through the velocity resonance conditions, the static and non-static PQS molecules are obtained. Under the condition of different parameters, the dynamic characteristics of the PQS molecules transmission process are analyzed. An interesting phenomenon of the PQS molecular interaction is found. We find that under the certain conditions, the PQS molecule composed of two solitons can evolve into the stable new form. Moreover, the soliton-asymmetric soliton molecule are obtained by the parameters control.