Abstract We report on the growth of a co-doped divalent-metal monotungstate crystal, Yb3+,Li+:ZnWO4, its structure refinement, thermo-mechanical properties and polarized Raman spectra. Yb3+,Li+:ZnWO4 crystals are grown by the Czochralski method using Pt/Rh and Pt crucibles. The nature of crystal coloration is discussed and assigned to color centers based on oxygen vacancies as well as Fe2+(Fe3+) species and, possibly, other uncontrolled impurities of transition metal ions. Oxidizing annealing at 800 °C helps to improve the transparency of Yb3+,Li+:ZnWO4 leading to a weak residual pink coloration. Yb3+,Li+:ZnWO4 was confirmed to be monoclinic (sp. gr. P2/c – C42h, No. 13) with lattice constants a = 4.702(2) A, b = 5.718(6) A, c = 4.930(4) A and β = 90.713(5)°. The coefficients of linear thermal expansion are α[100] = 11.71, α[010] = 9.90 and α[001] = 7.01 [10−6 K−1]. The melting point of the crystal is at 1166 °C and no thermal effects are found below the melting point. The Yb3+,Li+:ZnWO4 crystal shows intense and strongly polarized Raman spectra with the most intense mode at 906.0 cm−1 assigned to the W – O stretching vibrations in the [WO6] octahedra. It is thus a promising gain medium for laser emission at ∼1 μm and for self-Raman frequency conversion.

中文翻译：

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单斜晶单钨酸锌 Yb3+,Li+:ZnWO4：第一部分。直拉生长、结构细化和拉曼光谱

摘要 我们报告了共掺杂二价金属单钨酸盐晶体 Yb3+,Li+:ZnWO4 的生长、其结构细化、热机械性能和偏振拉曼光谱。Yb3+,Li+:ZnWO4 晶体使用 Pt/Rh 和 Pt 坩埚通过直拉法生长。讨论了晶体着色的性质，并根据氧空位以及 Fe2+(Fe3+) 物质以及可能的其他不受控制的过渡金属离子杂质将其分配给色心。800 °C 的氧化退火有助于提高 Yb3+,Li+:ZnWO4 的透明度，从而导致微弱的残留粉红色着色。Yb3+,Li+:ZnWO4 被证实是单斜晶系（sp. gr. P2/c – C42h, No. 13），晶格常数 a = 4.702(2) A, b = 5.718(6) A, c = 4.930(4) A 和 β = 90.713(5)°。线性热膨胀系数为 α[100] = 11.71，α[010] = 9。90 和 α[001] = 7.01 [10−6 K−1]。晶体的熔点为 1166 °C，在熔点以下未发现热效应。Yb3+,Li+:ZnWO4 晶体显示出强烈和强偏振的拉曼光谱，在 906.0 cm-1 处的最强模式分配给 [WO6] 八面体中的 W-O 伸缩振动。因此，它是一种很有前途的增益介质，用于~1μm 的激光发射和自拉曼频率转换。