Large lattice constant Y₃Al₅O₁₂, Gd₃Ga₅O₁₂ (GGG), Y₃Sc₂Ga₃O₁₂ (YSGG), Gd₃Sc₂Ga₃O₁₂, Ca_0.4Mg_0.25Zr_0.65Gd_2.6Ga_4.1O₁₂ (CaMgZr:GGG), and Gd_1.17Y_1.83Sc₂Ga₃O₁₂ (GYSGG) substrate crystals with 2 in. in diameter are grown by the Czochralski (Cz) method, their physical, chemical, and optical properties are analyzed and compared in details. The X‐ray rocking curves (XRCs) illustrate that the as‐grown crystals possess high crystalline quality. The lattice constants of six crystals are calculated and that of GYSGG can be easily adjusted in the range of 1.2450–1.2565 nm by changing the Gd/Y proportion. The dislocation densities on the (111)‐crystalline face are about 10² cm⁻² order of magnitude. The thermal conductivities of six crystals are measured to be 11.72, 8.98, 6.83, 5.45, 4.67, and 4.66 W m⁻¹ K⁻¹, respectively. It is found that the thermal expansion coefficients of six crystals can be reduced by annealing at 1273 K for 60 h. In addition, the transmission spectra show that the six crystals have excellent transparency and the coefficients of the Sellmeier equation are fitted by the calculated refractive indices. These results of the six crystals can provide the necessary parameters and references for the selection of suitable substrate materials or laser host crystals.

中文翻译：

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六种大晶格常数石榴石单晶的生长和性能研究

大晶格常数Y ₃ Al ₅ O ₁₂，Gd ₃ Ga ₅ O ₁₂（GGG），Y ₃ Sc ₂ Ga ₃ O ₁₂（YSGG），Gd ₃ Sc ₂ Ga ₃ O ₁₂，Ca _0.4 Mg _0.25 Zr _0.65 Gd _2.6 Ga _4.1 O ₁₂（CaMgZr：GGG）和Gd _1.17 Y _1.83 Sc ₂ Ga ₃ O ₁₂通过切克劳斯基（Cz）方法生长直径为2英寸（GYSGG）的衬底晶体，并对其物理，化学和光学性质进行了分析和详细比较。X射线摇摆曲线（XRC）表明，所生长的晶体具有较高的晶体质量。通过改变Gd / Y比例，可以计算出六个晶体的晶格常数，并且可以在1.2450–1.2565 nm的范围内轻松调整GYSGG的晶格常数。（111）晶面上的位错密度约为10 ²  cm ^-2数量级。测得六个晶体的热导率分别为11.72、8.98、6.83、5.45、4.67和4.66 W m ^-1  K ^-1， 分别。发现在1273 K下退火60 h可以降低六个晶体的热膨胀系数。另外，透射光谱表明这六个晶体具有优异的透明性，并且Sellmeier方程的系数通过计算的折射率拟合。六个晶体的这些结果可以为选择合适的衬底材料或激光主体晶体提供必要的参数和参考。