基于被动锁模掺镱光纤激光器集总模型，仿真研究了掺杂光纤的有限增益带宽对激光器输出特性的影响。仿真结果表明，被动锁模掺镱光纤激光器的输出脉冲宽度和激光器运行状态都受到增益带宽的影响。激光器输出脉冲宽度随增益带宽的增大而增大；通过线性调控腔内净色散的大小，发现在较大增益带宽情况下，较小的色散值就可以使激光器工作在自相似状态，即激光器工作在自相似状态时所需的腔内净色散条件范围更大。另外，对不同增益带宽下的激光器输出脉冲对之间的相互作用情况进行了仿真。仿真结果表明，非线性相移在抛物线形脉冲间的作用中起着关键的作用，而非线性相移受增益带宽的影响，因此较大的增益带宽下脉冲之间的相互作用力更强。

Based on a lumped model of a passively mode-locked Yb-doped fiber laser, the influence of the limited gain bandwidth on the laser′s output characteristics is investigated numerically. Simulation results show that the duration of the output pulse and the operating regimes are determined by the gain bandwidth. The pulse duration increases with the gain bandwidth increasing. By changing the intra-cavity average dispersion monotonically, it is demonstrated that under the condition of wide gain bandwidth, the laser operates in the self-similar regimes under a large range of cavity parameters. In addition, the interaction of pulse pair in distinct gain bandwidth is also studied. Simulation results show that the nonlinear phase shift plays an important role in pulses interaction, and the nonlinear phase shift is determined by the gain bandwidth, therefore the wider gain bandwidth leads to the stronger interaction forces between the pulses.