J-mixing Effect of the Crystal-field on the Spectroscopic Characteristics of Rare-earth Doped Laser Crystals

By using the re-derived formulae for both line-strength of electricdipole transition and simple J-mixing coefficients within the 4f shell in a rare-earthion, the spectroscopic properties of the luminescent material Eu3+ =Y2O3 and laser crystals Tb3+:=YAlO3 and Nd3+:YVO4, are investigated in detail. On the basis of three fitting Ω parameters and the effective reduced matrix elements, the spectral linestrengths, spontaneous emission probabilities, fluorescent branching ratios and lifetimeare calculated. The better agreement between theoretical results and experimental dataindicates the importance of J-mixing in the spectroscopic study of laser crystals.

掺杂对磷酸钛氧钾单晶拉曼光谱的影响

本文研究了掺金属元素Ｃｅ和Ｎｂ的磷酸钛氧钾（ＫＴｉＯＰＯ４，简称ＫＴＰ）晶体在不同几何配置下的拉曼光散射。讨论了掺杂对ＫＴＰ拉曼光谱的影响。拉曼光谱大的散射强度说明晶体有大的非线性光学特性。从掺铈和掺铌ＫＴＰ中氧八面体和氧四面体相对于ＫＴＰ的频率位移可知，稀土金属离子Ｃｅ比Ｎｂ离子对ＫＴＰ拉曼光谱的影响更大。

固态量子存储器

量子通信发展的最终目标是构建全国乃至洲际的大尺度量子通信网络,然而受限于光子损耗,目前安全量子通信的距离被限制在百公里量级。目前有两种方案可以有效拓展安全量子通信的工作距离,即量子中继方案和量子加密U盘方案。这两套方案所需要的核心器件都是高性能量子存储器,所以针对具体通信方案优化存储器技术指标,演示基于量子存储器的量子通信技术,是现阶段量子通信研究的核心任务。本项目针对以上科学问题及关键技术,以具体应用方案为导向,基于固体中的稀土离子系综研制高性能固态量子存储器。本文主要介绍项目实施以来相关方面的研究内容以及研究进展。