Ion Dynamics in Superionic Conductors Studied by a Spectral Hole-Burning Effect

通过光谱烧孔效应研究超离子导体中的离子动力学

基本信息

批准号：
01460069
负责人：
SUEMOTO Tohru
金额：
$ 3.97万
依托单位：
The Institute for Solid State Physics, The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-01460069/
关键词：
Superionic conductor Hole-burning Ziroconia FLN Ceria イオン伝導ガラス発光

项目摘要

(1) The optical absorption and luminescence spectra of ^7F_0 -^5 D_0 transition in Eu^<3+> ions are studied for Eu^<3+> -doped CeO_2 -Y_2 O_3 and ZrO_2-Y_2O_3 (YSZ) systems. From a detailed study of the luminescence bands under site selective excitation, following results are obtained. In Eu^<3+> /CeO^2-Y_2O_3, three types of trivalent ion sites are found ; the site without vacancy, with one vacancy on the nearest neighbor site, and with one vacancy on the 2nd nearest site. In YSZ, trivalent ion site without vacancy and one and two vacancies on the nearest nieghbor site are found.(2) The FLN(fluorescence line narrowing) spectra are studied in Eu^<3+> -doped YSZ(ZrO_2-Y_2O_3) crystals with various compositions. The homogeneous line width is found to be proportional to T^<2.6> between 80K and 300K. Since the homogeneous and inhomogeneous line widths have different composition dependence, R(=GAMMA_<inhomo>/GAMMA_<homo>) has a maximum value at certain composition. It is found that the 19mol% YSZ has a maximum value, R=5000, at 20K. This result suggests usefulness of the Eu^<3+>/YSZ system for a frequency domain optical memory.(3) In 10mol%YSZ doped with 2%Pr^<3+>, we found a persistent hole-burning effect for ^3H_4-^1D_2 transition at 6115A. The hole can be burned below 25K and its width is 0.35GHz at 4.2K. The hole width, which is assumed to be equal to 2GAMMA_<homo>, has a T^<1.3> temperature dependence. This temperature dependence is very similar to that of the dye molecules embedded in polymers, and strongly suggests that the dephasing mechanism in this system involves a coupling of the rare-earth ions with TLS(two level system). The persistent hole can be used as a new tool to investigate the microscopic structures and the interaction of the mobile ions with the defect centers in YSZ. A demonstration as a frequency domain memory will be also a fruitful subject as a next step.

(1)研究了Eu^<3+>掺杂CeO_2-Y_2O_3和ZrO_2-Y_2O_3(YSZ)体系中Eu^<3+>离子^7F_0-^5D_0跃迁的光吸收和发光光谱。通过对位点选择性激发下的发光带的详细研究，获得以下结果。在Eu^<3+> /CeO^2-Y_2O_3中，发现了三种类型的三价离子位点；没有空位的站点，最近的相邻站点有 1 个空位，第二个最近的站点有 1 个空位。在YSZ中发现了无空位的三价离子位点以及最近邻位点上的1个和2个空位。(2)研究了Eu^<3+>掺杂YSZ(ZrO_2-Y_2O_3)晶体的FLN(荧光线窄化)光谱。具有各种成分。发现均匀线宽在80K和300K之间与T^<2.6>成比例。由于均匀线宽和非均匀线宽具有不同的成分依赖性，因此 R(=GAMMA_<inhomo>/GAMMA_<homo>) 在特定成分下具有最大值。结果发现，19mol% YSZ 在 20K 时具有最大值，R=5000。这一结果表明Eu^<3+>/YSZ系统对于频域光学存储器的有用性。(3)在掺杂2%Pr^<3+>的10mol%YSZ中，我们发现了^的持续烧孔效应。 6115A 处的 3H_4-^1D_2 转换。 25K以下可烧孔，4.2K时孔宽为0.35GHz。假设孔宽度等于 2GAMMA_<homo>，它具有 T^<1.3> 温度依赖性。这种温度依赖性与嵌入聚合物中的染料分子的温度依赖性非常相似，强烈表明该系统中的移相机制涉及稀土离子与 TLS（两级系统）的耦合。持久空穴可以作为研究微观结构以及移动离子与 YSZ 缺陷中心相互作用的新工具。作为下一步，频域存储器的演示也将是一个富有成果的主题。