Abstract Transparent Cr4+:YAG ceramics with high optical quality was fabricated using solid state reactive sintering. The effect of CaO/MgO ratio on Cr3+ →Cr4+ conversion efficiency was studied. In samples with fixed total amount of divalent ions, Cr4+ conversion efficiency is growing with increasing of Ca2+/Mg2+ ratio. Samples were fully transparent after sintering at 1840 °C for 8 h and annealing in air at 1400 °C for 10 h. Some rather specific defects were observed, their nature investigated and model of forming proposed. Most probable nature of these defects is tungsten inclusions in ceramics sourced by tungsten vapors inside the vacuum furnace. This is far more pronounced with high calcium oxide presence in ceramic samples. The main saturable absorber characteristics were systematically measured.

中文翻译：

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CaO/MgO比对YAG:Cr4+陶瓷可饱和吸收体中Cr3+向Cr4+转化效率的影响

摘要 采用固态反应烧结制备了具有高光学质量的透明Cr4+:YAG陶瓷。研究了CaO/MgO比例对Cr3+→Cr4+转化效率的影响。在二价离子总量固定的样品中，Cr4+转化效率随着Ca2+/Mg2+比的增加而增加。样品在 1840°C 下烧结 8 小时并在 1400°C 下在空气中退火 10 小时后完全透明。观察到了一些相当具体的缺陷，研究了它们的性质并提出了成型模型。这些缺陷最可能的性质是由真空炉内的钨蒸气产生的陶瓷中的钨夹杂物。这在陶瓷样品中氧化钙含量高的情况下更为明显。系统地测量了主要的可饱和吸收器特性。