Abstract Rb4Li2TiOGe4O12 (RLTG) crystals were grown with excess Rb2CO3 and LiF by the top-seeded solution growth (TSSG) method. Several attempts of growth at different cooling rates were carried out, a crystal with better quality and dimensions of 39 × 38 × 23 mm3 was obtained at the lowest cooling rate. The transmission spectra of crystal plates with various thicknesses show that the transmittance in the infrared (IR) above 3.5 μm decreases as crystal thickness increases, but the crystal plate with thickness of 10.47 mm still shows adequate transmittance in this range. The refractive indices of the crystal were measured in the wavelength range of 0.363 - 1.014 μm, and the Sellmeier equations were obtained by fitting the measured refractive indices. The derived result shows that the crystal may have the possibility of phase matching in the mid-IR range.

中文翻译：

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非线性光学晶体Rb4Li2TiOGe4O12的生长及光学特性

摘要 Rb4Li2TiOGe4O12 (RLTG) 晶体是用过量的 Rb2CO3 和 LiF 通过顶部种子溶液生长 (TSSG) 方法生长的。进行了多次不同冷却速率下的生长尝试，在最低冷却速率下获得了质量更好、尺寸为 39 × 38 × 23 mm3 的晶体。不同厚度晶体板的透射光谱表明，3.5 μm以上的红外（IR）透射率随着晶体厚度的增加而降低，但厚度为10.47 mm的晶体板在该范围内仍表现出足够的透射率。在 0.363 - 1.014 μm 的波长范围内测量晶体的折射率，并通过拟合测量的折射率获得 Sellmeier 方程。