Abstract Optical properties of YAG crystals grown and annealed under different atmosphere conditions have been compared. Simultaneously we have registered the surface composition of crystals and content of basic admixtures in the crystals grown under the reducing conditions. Unlike YAG grown under weakly oxidizing conditions in Ir crucibles and bleached under oxidizing annealing, YAG Mo crystals grown in Mo crucibles under reducing Ar + CO atmosphere can be bleached by both oxidizing and reducing thermal annealing. The bleaching of YAG Mo is not reversed by further annealing under any available conditions. Mechanisms of this phenomenon have been discussed, including a possible role of admixtures in elimination of color centers in YAG grown under the reducing conditions.

中文翻译：

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通过热退火控制 YAG 晶体的光学性能

摘要 比较了不同气氛条件下生长和退火的YAG晶体的光学性能。同时，我们记录了晶体的表面组成和在还原条件下生长的晶体中基本混合物的含量。与在 Ir 坩埚中弱氧化条件下生长并在氧化退火下漂白的 YAG 不同，在还原 Ar + CO 气氛下在 Mo 坩埚中生长的 YAG Mo 晶体可以通过氧化和还原热退火来漂白。在任何可用条件下，进一步退火都不会逆转 YAG Mo 的漂白。已经讨论了这种现象的机制，包括混合物在消除还原条件下生长的 YAG 中的色心方面的可能作用。