We present new high-resolution absorption data for the important sesquioxide laser material Yb:Lu2O3 for the spectral range of 880–1020 nm, at various temperatures between 8 and 300 K, and for the zero-phonon region from 960 to 990 nm, at temperatures from 8 to 300 K. We have experimentally observed the C3i (0,1)–(1,3) transition for the first time, located at 880.7 nm at 8 K. Based on high confidence fitting functions to the experimental data, we provide the first complete compilation of all observed electronic and electronic–vibrational transitions. Detailed fitting and plots of the C2 and C3i zero-line data show an evolution of the linewidth from being predominantly electronic below about 100 K to being dominated by thermal processes above 100 K. We have also found evidence for a “soft” phase transition between 80 and 100 K that changes the local coordination environment.

中文翻译：

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Yb:Lu2O3 水热生长的单晶高分辨率吸收光谱在 8 到 300 K 之间获得

我们提供了重要的倍半氧化物激光材料 Yb:Lu2O3 的新高分辨率吸收数据，其光谱范围为 880–1020 nm，在 8 到 300 K 之间的不同温度下，以及 960 到 990 nm 的零声子区域，在温度从 8 到 300 K。我们首次通过实验观察到 C3i (0,1)–(1,3) 转变，位于 8 K 处的 880.7 nm。基于对实验数据的高置信度拟合函数，我们提供所有观察到的电子和电子振动跃迁的第一个完整汇编。C2 和 C3i 零线数据的详细拟合和绘图显示线宽从低于约 100 K 的主要电子到高于 100 K 的热过程主导的演变。