Characterization and Manipulation of Temporal Structures of Dispersive Waves in a Soliton Fiber Laser

Dispersive waves (DWs) are ubiquitous in nonlinear optical systems that host optical solitons. In particular, DWs in soliton fiber lasers have attracted continuous interest over the past decades since they are closely related to laser soliton instabilities. Meanwhile, intra-cavity DWs also play important roles in solion interactions. While previous studies mostly focused on their spectral properties, characterizations and manipulations of the intra-cavity DWs in the time domain remain unexplored. Here, we report the experimental studies on temporal structures of intra-cavity DWs, unveiling their exponentially-decaying profiles which can be manipulated by varying cavity parameters, following a simple analytic model. We also studied the evolution dynamics of the intra-cavity DWs under abrupt cavity parameter variations. We observed that both the amplitude and the width of the DW waveform went through variations as the pump power was changed, while their evolution trajectories followed intimately that of the soliton energy. These results provide insights into the DW emission mechanism in mode-locked lasers, and the control methods of intra-cavity DWs may find potential applications in the fields of ultrafast pulse generation and soliton dynamics.