Abstract Single crystal of La3Ga5.5Ta0.5O14 (LGT) doped with Dy3+ was fabricated by the Czochralski technique and investigated employing methods of optical spectroscopy. Polarized optical absorption spectra and luminescence spectra were recorded at room temperature. Unpolarized absorption and luminescence spectra were recorded at 10 K. Spectra of blue luminescence related to transitions 4I15/2, 4F9/2 → 6H15/2 were recorded at several temperatures in the 300–773 K region. Dy3+ ions have the same symmetry sites in LGT but their spectra show inhomogeneous broadening due to structural disorder of the host and are markedly anisotropic. Results of the Judd-Ofelt treatment made it possible to assess emission cross sections for the 4F9/2 → 6H15/2 blue luminescence and for the 4F9/2 → 6H13/2 yellow luminescence employing Fuchtbauer-Ladenburg formula and reciprocity method. In particular, a spectral distribution of La3Ga5.5Ta0.5O14: Dy3+ σ-polarized luminescence band with an emission cross section σem = 0.51 × 10−20 cm2 at 573.5 nm is favorable for a laser operation in the visible. Interpretation of the effect of temperature on the blue emission spectra leads to the conclusion that La3Ga5.5Ta0.5O14: Dy3+ is promising for application as luminescent thermometer.

中文翻译：

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La3Ga5.5Ta0.5O14单晶中Dy3+离子的光谱特性

摘要 采用直拉技术制备了掺杂 Dy3+ 的 La3Ga5.5Ta0.5O14 (LGT) 单晶，并采用光谱学方法进行了研究。在室温下记录偏振光吸收光谱和发光光谱。在 10 K 处记录了非偏振吸收和发光光谱。在 300-773 K 区域的几个温度下记录了与跃迁 4I15/2、4F9/2 → 6H15/2 相关的蓝色发光光谱。Dy3+ 离子在 LGT 中具有相同的对称位点，但由于主体的结构无序，它们的光谱显示出不均匀的展宽，并且具有明显的各向异性。Judd-Ofelt 处理的结果使得使用 Fuchtbauer-Ladenburg 公式和互易法评估 4F9/2 → 6H15/2 蓝色发光和 4F9/2 → 6H13/2 黄色发光的发射截面成为可能。特别是，La3Ga5.5Ta0.5O14: Dy3+ σ 偏振发光带的光谱分布在 573.5 nm 处具有发射截面 σem = 0.51 × 10-20 cm2，有利于可见光下的激光操作。解释温度对蓝色发射光谱的影响得出的结论是，La3Ga5.5Ta0.5O14:Dy3+ 有望用作发光温度计。