We present Emission and absorption cross sections of thulium doped calcium fluoride (Tm:CaF2) in the visible to short wave infrared (SWIR) wavelength range for temperatures between 80 K and 300 K. For spectral regions of high and low absorption the McCumber relation and the Fuchtbauer–Ladenburg equation have been used to give reliable results. Furthermore, an estimation for the cross relaxation efficiency is derived from the emission spectra as a function of doping concentration and temperature. In addition, nearly re-absorption-free fluorescence lifetimes for various doping concentrations were studied. It was found that a double exponential fit model is better suited than a migration model to represent the fluorescence decay curves. The measurement results are interpreted in the light of the application of Tm:CaF2 as an efficient active medium in high-energy class diode-pumped solid state lasers.

中文翻译：

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Tm:CaF2 的温度相关吸收和发射光谱

我们展示了掺铥氟化钙 (Tm:CaF2) 在可见光到短波红外 (SWIR) 波长范围内的发射和吸收截面，温度介于 80 K 和 300 K 之间。对于高吸收和低吸收的光谱区域，McCumber 关系和Fuchtbauer-Ladenburg 方程已被用于给出可靠的结果。此外，交叉弛豫效率的估计是从作为掺杂浓度和温度函数的发射光谱得出的。此外，研究了各种掺杂浓度下几乎无重吸收的荧光寿命。发现双指数拟合模型比迁移模型更适合表示荧光衰减曲线。根据 Tm 的应用解释测量结果：