Luminescence spectroscopy of excitons and antisite defects in Lu3Al5O12 single crystals and single-crystal films
Luminescence spectroscopy of excitons and antisite defects in Lu3Al5O12 single crystals and single-crystal films
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DOI：
10.1134/s0030400x08010116
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发表时间：
2008
影响因子：
0.6
通讯作者：
Y. Zorenko;T. Voznyak;V. Gorbenko;T. Zorenko;A. Voloshinovskii;V. Vistovsky;M. Nikl;K. Nejezchleb;V. Kolobanov;D. Spasskiĭ
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文献类型：
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作者：
Y. Zorenko;T. Voznyak;V. Gorbenko;T. Zorenko;A. Voloshinovskii;V. Vistovsky;M. Nikl;K. Nejezchleb;V. Kolobanov;D. Spasskiĭ
通过脉冲 X 射线和同步加速器辐射激发两种模型物体（LuAG 单晶和单晶薄膜）的时间分辨光谱动力学研究，分析了镥铝石榴石 Lu3Al5O12（LuAG）的本征发光性质。由于结晶机制和方法的不同，这些物体的特征是LuAlantisite缺陷浓度显着不同。 LuAG单晶中发光中心（自陷激子（STE）、反位点缺陷附近局域激子和LuAlantisite缺陷）的能量结构已经建立。对于通过含 Pb 助熔剂液相外延生长的单晶 LuAG 薄膜，已确定了以下发光中心的能量参数：石榴石晶格的规则（不受反位缺陷的存在干扰）位点的 STE 和位于 Pb2+ 离子附近的激子。与杂质 Pb2+ 离子背景发射相关的发光中心结构也已在紫外和可见光范围内建立。与双卤化物空穴自捕获相反，LuAG 中形成了类似于简单氧化物（Al2O3、Y2O3）中的 STE 的自捕获态；这种状态是由单电荷 O− 离子形式的自捕获空穴和位于 Lu3+ 阳离子激发能级的电子形成的。
The nature of the intrinsic luminescence of the lutetium aluminum garnet Lu3Al5O12(LuAG) has been analyzed on the basis of time-resolved spectral kinetic investigations upon excitation of two model objects, LuAG single crystals and single-crystal films, by pulsed X-ray and synchrotron radiations. Due to the differences in the mechanisms and methods of crystallization, these objects are characterized by significantly different concentrations of LuAlantisite defects. The energy structure of luminescence centers in LuAG single crystals (self-trapped excitons (STEs), excitons localized near antisite defects, and LuAlantisite defects) has been established. For single-crystal LuAG films, grown by liquid-phase epitaxy from a Pb-containing flux, the energy parameters of the following luminescence centers have been determined: STEs in regular (unperturbed by the presence of antisite defects) sites of the garnet lattice and excitons localized near Pb2+ions. The structure of the luminescence centers, related to the background emission of impurity Pb2+ions, has also been established in the UV and visible ranges. It is suggested that, in contrast to the two-halide hole self-trapping, a self-trapped state similar to STEs in simple oxides (Al2O3, Y2O3) is formed in LuAG; this state is formed by self-trapped holes in the form of singly charged O−ions and electrons localized at excited levels of Lu3+cations.