We present the results of a comprehensive spectroscopic investigation pertaining to laser potential evaluation of the 3-micron Dy³⁺ mid-IR transition in the low-maximum phonon energy host barium fluoride (BaF₂). This investigation involved absorption, fluorescence, and decay time measurements, recorded for a range of temperatures. Laser-relevant parameters such as absorption and stimulated-emission cross sections, quantum-efficiencies, and radiative lifetimes were determined for room temperature (300 K) and liquid nitrogen temperature. The peak stimulated emission cross section was found to be 0.45×10⁻²⁰ cm² at room temperature and 1.58×10⁻²⁰ cm² at 77 K. The gain cross sections, predictive of laser potential, were also derived. Finally, an examination of the nature of the non-radiative decay rates as a function of temperature was performed, showing the degree to which multi-phonon relaxation and other non-radiative pathways affect the overall fluorescence behavior.

中文翻译：

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与 3 µm 中红外激光电位有关的镝掺杂 BaF2 单​​晶的光谱研究

我们展示了与低最大声子能量宿主氟化钡 (BaF ₂ ) 中3 微米 Dy ³⁺中红外跃迁的激光电位评估有关的综合光谱研究结果。这项研究涉及吸收、荧光和衰减时间测量，记录了一系列温度。在室温 (300 K) 和液氮温度下确定了与激光相关的参数，例如吸收和受激发射截面、量子效率和辐射寿命。发现峰值受激发射截面在室温下为0.45×10 ^-20 cm ²和1.58×10 ^-20 cm ²在 77 K 处。还导出了可预测激光电位的增益截面。最后，对作为温度函数的非辐射衰减率的性质进行了检查，显示了多声子弛豫和其他非辐射途径影响整体荧光行为的程度。