Transition Between Quadratic and Quartic Solitons With OAM Modes in Passive Driven Fiber Resonator

Solitons are particular wave packets that can propagate and maintain stable shape by complex balance between dispersion and nonlinear effects. Very recently, the new concept of pure-quartic soliton has been widely discussed due to its extraordinary energy scaling law, arising from the interaction between quartic dispersion and nonlinear Kerr effects. In our work, we numerically investigate the nonlinear dynamics of pure-quartic solitons with orbital angular momentum (OAM) in passive driven fiber resonator. The dual-concentric Germania-doped ring-core fiber (GRF) is specially designed to support OAM modes in the resonator. Since different OAM modes are related to different dispersion conditions, the transition between conventional quadratic soliton and pure-quartic soliton can be achieved by changing the OAM mode orders of the driving continuous wave source. Our work provides a promising method to control the dispersion for soliton formation through transverse structured mode conversion, and might benefit the investigation of spatio-temporal solitons in the future.