We explore the possibility of using the luminescence of LiYF:Er to measure cryogenic temperatures. Temperature dependences (2.5 K → 190 K) of the luminescence intensity ratios and linewidths are studied in the regions of infrared transitions I → I (∼1.5 μm) and I → I (∼0.98 μm) using high-resolution Fourier spectroscopy. Pairs of spectral lines 6550–6510 cm, 10176–10161 cm, and 6482–6478 cm can be used for ratiometric Boltzmann thermometry with maximum absolute sensitivity at temperatures of 28.8, 10.8, and 2.9 K, respectively, and corresponding relative sensitivities of 6.9, 18.5, and 70% K at these temperatures. The temperature dependence of the linewidth of 6510 cm line is favorable for measuring higher temperatures.

中文翻译：

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LiYF4:Er3+ 用于近红外发光低温测定法

我们探索利用 LiYF:Er 的发光来测量低温的可能性。使用高分辨率傅里叶光谱研究了红外跃迁 I → I (∼1.5 μm) 和 I → I (∼0.98 μm) 区域中发光强度比和线宽的温度依赖性 (2.5 K → 190 K)。 6550–6510 cm、10176–10161 cm 和 6482–6478 cm 的谱线对可用于比例玻尔兹曼测温，分别在 28.8、10.8 和 2.9 K 的温度下具有最大绝对灵敏度，相应的相对灵敏度为 6.9，在这些温度下，K 值分别为 18.5 和 70%。 6510 cm 线的线宽的温度依赖性有利于测量更高的温度。