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+>离子中^7f_0-^5 d_0的光学吸收和发光光谱，用于EU^<3+> doped CEO_2 -Y_2 O_3和ZRO_2 -Y_2O_2O_3（YSZ）系统。从现场选择性激发下的发光波段的详细研究中获得以下结果。在EU^<3+> /CEO^2-Y_2O_3中，发现了三种三价离子位点；该地点没有空缺，最近的邻居地点有一个空缺，第二个位置有一个空缺。在YSZ中，发现最近Nieghbor位点上没有空位的三价离子位点。（2）（2）在EU^<3+>掺杂的YSZ（ZRO_2 -Y_2O_3）中，研究了FLN（荧光线变窄）光谱。发现同质线宽度与80k至300k之间的T^<2.6>成正比。由于均匀和不均匀的线宽度具有不同的组成依赖性，因此r（= gamma_ <inhomo>/gamma_ <homo>）在某些组成下具有最大值。发现19mol％ysz的最大值为r = 5000，在20k时。该结果表明EU^<3+>/YSZ系统对频域光学内存的有用性。（3）在10mol％YSZ中掺杂了2％Pr^<3+>，我们发现^3H_4-^1d_2在6115a时的持续孔燃烧效果。该孔可以在25K以下燃烧，其宽度为4.2k时为0.35GHz。假定孔宽度等于2Gamma_ <homo>，具有T^<1.3>温度依赖性。该温度依赖性与聚合物中嵌入的染料分子的依赖性非常相似，并强烈表明该系统中的脱态机理涉及将稀土离子与TLS（两个级别系统）耦合。持续的孔可以用作研究微观结构的新工具，以及移动离子与YSZ中缺陷中心的相互作用。作为频域记忆的演示也将是下一步的富有成果的主题。