掺Eu^(3+)近化学计量比铌酸锂晶体的生长与光谱特性  

Growth and optical spectra of Eu^(3+)-doped near-stoichiometric lithium niobate crystal

作　　者：万云涛[1] 夏海平[1] 张嗣春[1] 章践立[1] 

机构地区：[1]宁波大学光电子功能材料研究所,浙江宁波315211

出　　处：《功能材料》2011年第1期112-115,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(50972061;600777030);宁波市场科技局资助项目(2009A610007;2007A22010)

摘　　要：以K2O为助熔剂,采用大的固液界面温度梯度(90～100℃),应用坩埚下降法成功地生长了含Eu3+离子(原料中初始Eu3+摩尔浓度0。95%)的近化学计量比铌酸锂单晶。测定了晶体中Eu3+离子的浓度以及晶体的室温吸收光谱、激发与发射光谱。根据晶体吸收边的位置,估算出晶体中Li2O的摩尔分数含量为约49.47%。分别在吸收光谱与激发光谱中观测到特征的Eu3+吸收与激发峰。在394nm波长光的激发下观测到5 D0—7FJ(0,1,2,3,4)的荧光发射峰。根据测得的不同部位Eu3+离子的浓度与不同部位晶片的吸收和发射峰的强度情况,可推断出Eu3+离子浓度在晶体中的分布沿着生长方向逐渐减少。根据测得的Eu3+浓度,计算得到有效分凝系数为约1.02。The near-stoichiometric LiNbO3 single crystals doped Eu3＋ in 0.95mol% concentration in the raw compositions were grown by the Bridgman method under the conditions of taking K2O as flux,and taking high temperature gradient of about 90-100℃/cm of the interface as seeding and growing of the crystal.The Eu3＋ ion concentrations,the absorption spectra,excitation spectra and emissions of Eu3＋-doped near-stoichiometric LiNbO3 were measured.Two absorption peaks at 394nm（7F0—5D3）,468nm（7F0—5D2） and the level transitions of Eu3＋ from 7F0 to 5D4,5G3,5L6,5D3,5D2,5D1 and 5D0 level were obtained from their absorption and excitation spectra.The content of Li2O in crystal,to be 49.47mol%,was estimated from the absorption edge of Eu3＋-doped LiNbO3 crystal.The sharp emission peaks from 5D0 to 7FJ（0,1,2,3,4） were observed under excitation of 394nm light.It could be deduced that the Eu3＋ concentration increased gradually along growing direction by comparing the absorption and emission intensity,and the measured Eu3＋ ion concentrations between the upper and lower parts of the crystal.The effective distribution coefficient of Eu3＋,to be about 1.02,was estimated from the measured Eu3＋ ion concentration.

关 键 词：Eu3+离子 K2O 近化学计量比铌酸锂 坩埚下降法 光谱 

分 类 号：TB381[一般工业技术—材料科学与工程]