Genetic Analysis of the Accompanying of (Lu,Y)3Al5O12:Ce in LuxY1-xAlO3:Ce Single Crystals
LuxY1-xAl 3:Ce晶体中伴生(Lu,Y3 Al5O12:Ce相成因研究

LuxY1-xAlO3:Ce single crystal samples were prepared by the Czochralski method. Based on X-ray diffraction (XRD) and composition analyses, and analysis of phase diagram of Lu2O 3-Al2O3 and the structural stability of LuxY1-xAlO3:Ce, it is supposed that as the content of Lu increase, the melt delamination is exacerbated, and the crystallization interval of Lux 1-xAlO3:Ce in the phase diagram may shift towards the interval rich in Lu, resulting in the accompaniment of (Lu,Y)3Al5O12:Ce on the top of LuxY1-xAlO3 :Ce single crystals. With the increase of the content of Lu, the thermal stability of LuxY1-xAlO3:Ce single crystals decreases, the oxygen vacancy in those crystals furthers the decrease, so the seed surface tends to decompose into (Lu,Y3 Al5O12:Ce and (Lu,Y)4Al2O9:Ce while seeding, and the former decomposition product provides the crystal nucleus to induce crystallization of (Lu,Y3Al 5O12:Ce, resulting in the accompaniment of (Lu,Y)3Al5O12:Ce on the coat of LuxY1-xAlO3:Ce single crystals. An adjustment of the melt composition to make the mol ratio n((Lu,Y)2O3):n(Al2O3) equal to 1.17--1.00, and a greater temperature gradient inside the melt and at the solid liquid interface to improve melt convection, restrain melt delamination and the decomposition on the seed surface may contribute to the acquisition of Lux Y1-xAlO3:Ce with high Lu content.