This paper discusses a unified theoretical approach to model the spectral and temporal properties of various quasi-continuous-wave (quasi-CW) fiber lasers. The unified spectral evolution model and temporal evolution model of quasi-CW fiber lasers are established by demonstrating the nonlinear propagation equations with gain coefficient and analyzing the corresponding definite conditions and computation methods for effective simulations. Simulation results based on the two unified models are given to show their capacities and application scope in describing the basic spectral and temporal properties of typical quasi-CW fiber lasers involving single gain mechanism with a simple structure. Furthermore, the two unified models could also be extended to analyze the spectral and temporal properties of quasi-CW fiber lasers involving a hybrid gain mechanism or with a composite structure. Overall, the unified spectral evolution model and temporal evolution model could provide a useful tool to describe and design quasi-CW fiber lasers and quasi-CW fiber amplifiers.

中文翻译：

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准连续光纤激光器光谱和时间特性的统一模型

本文讨论了一种统一的理论方法来模拟各种准连续波（准连续波）光纤激光器的光谱和时间特性。通过论证带增益系数的非线性传播方程，分析相应的确定条件和计算方法，建立了准连续光纤激光器统一的光谱演化模型和时间演化模型，以进行有效的模拟。给出了基于这两种统一模型的仿真结果，展示了它们在描述具有简单结构的单增益机制的典型准连续光纤激光器的基本光谱和时间特性方面的能力和应用范围。此外，这两个统一模型还可以扩展到分析准连续光纤激光器的光谱和时间特性，包括混合增益机制或复合结构。总的来说，统一的光谱演化模型和时间演化模型可以为描述和设计准连续光纤激光器和准连续光纤放大器提供有用的工具。