We propose an energy transfer model with a cubic atomic population dependence to accurately model the behavior of various reported high-power erbium-doped fluoride fiber lasers operating near 2.8 microns. We first show that the previously introduced weakly interacting (WI) and strongly interacting (SI) models are not adequate for precisely modeling such high-power erbium-doped fluoride fiber lasers. We compare results obtained with the WI and SI models to the proposed model by simulating 4 different highly doped (7 mol.%) fiber lasers previously reported in the literature. Laser efficiencies and powers are reproduced with great accuracy. In addition, four other fiber laser systems based on erbium concentrations varying from 1–6 mol.% are also simulated with good accuracy using the proposed model with the exact same set of spectroscopic parameters, which confirms its validity for various erbium doping concentrations. Redshifting of laser wavelength is also taken into account by considering the full cross section spectra and computing signal powers over several wavelength channels.

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对具有立方能量传输率依赖性的 3 微米级掺铒氟化物光纤激光器进行建模

我们提出了一种具有立方原子布居依赖性的能量转移模型，以准确模拟各种报道的在 2.8 微米附近工作的高功率掺铒氟化物光纤激光器的行为。我们首先表明，先前引入的弱相互作用（WI）和强相互作用（SI）模型不足以精确建模此类高功率掺铒氟化物光纤激光器。我们通过模拟文献中先前报道的 4 种不同的高掺杂 (7 mol.%) 光纤激光器，将 WI 和 SI 模型获得的结果与所提出的模型进行比较。激光效率和功率可以非常精确地再现。此外，还使用具有完全相同的一组光谱参数的所提出的模型对其他四种基于铒浓度从 1-6 mol.% 变化的光纤激光系统进行了高精度模拟，这证实了其对于各种铒掺杂浓度的有效性。通过考虑全截面光谱并计算多个波长通道上的信号功率，还考虑了激光波长的红移。