Abstract Y3Al5O12 (YAG) single crystals doped with a fixed Ho3+ content of 0.5 at.% and various Yb3+ contents (Yb = 5, 10 and 15 at.%) have been successfully grown by the micro-pulling-down (μ-PD) method. The absorption spectra, fluorescence spectra and fluorescence decay curves were recorded at room temperature. The intense emission of Yb,Ho:YAG crystal centered at 2 μm corresponds to the 5I7 → 5I8 transition. Three intense emissions centered at 524–569 nm, 623–691 nm and 744–746 nm, correspond to the 5F4 + 5S2 → 5I8, 5F5 → 5I8 and 5F4 + 5S2 → 5I7 transitions, respectively. The possible energy transfer mechanisms were discussed intensively.

中文翻译：

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微下拉法生长的Yb3+、Ho3+掺杂Y3Al5O12单晶的光谱特性

摘要 Y3Al5O12 (YAG) 单晶掺杂了 0.5 at.% 的固定 Ho3+ 和各种 Yb3+ 含量（Yb = 5、10 和 15 at.%）已经通过微下拉 (μ-PD) 成功生长方法。在室温下记录吸收光谱、荧光光谱和荧光衰减曲线。以 2 μm 为中心的 Yb,Ho:YAG 晶体的强烈发射对应于 5I7 → 5I8 转变。三个集中在 524–569 nm、623–691 nm 和 744–746 nm 的强发射分别对应于 5F4 + 5S2 → 5I8、5F5 → 5I8 和 5F4 + 5S2 → 5I7 跃迁。对可能的能量转移机制进行了深入讨论。