物理化学学报 >> 2014, Vol. 30 >> Issue (9): 1752-1757.doi: 10.3866/PKU.WHXB201406183

光化学和辐射化学 上一篇    下一篇

不同掺杂浓度Tm3+:LiLuF4单晶的1800 nm荧光发射

李珊珊1, 夏海平1, 符立1, 董艳明1, 张加忠1, 谷雪梅1, 章践立1, 王冬杰1, 江浩川2, 陈宝玖3   

  1. 1. 宁波大学光电子功能重点实验室, 浙江宁波 315211;
    2. 中国科学院宁波材料所, 浙江宁波 315211;
    3. 大连海事大学物理系, 辽宁大连 116026
  • 收稿日期:2014-05-08 修回日期:2014-06-18 发布日期:2014-08-29
  • 通讯作者: 夏海平 E-mail:hpxcm@nbu.edu.cn
  • 基金资助:

    国家自然科学基金(51272109),宁波市自然科学基金(201401A6105016,2013A610126)及宁波大学王宽诚幸福基金(NBUWC001)资助项目

Fluorescent Emissions (1800 nm) of LiLuF4 Single Crystals Doped with Various Tm3+ Concentrations

LI Shan-Shan1, XIA Hai-Ping1, FU Li1, DONG Yan-Ming1, ZHANG Jia-Zhong1, GU Xue-Mei1, ZHANG Jian-Li1, WANG Dong-Jie1, JIANG Hao-Chuan2, CHEN Bao-Jiu3   

  1. 1. Key Laboratory of Photo-electronic Materials, Ningbo University, Ningbo 315211, Zhejiang Province, P. R. China;
    2. Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315211, Zhejiang Province, P. R. China;
    3. Department of Physics, Dalian Maritime University, Dalian 116026, Liaoning Province, P. R. China
  • Received:2014-05-08 Revised:2014-06-18 Published:2014-08-29
  • Contact: XIA Hai-Ping E-mail:hpxcm@nbu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (51272109), Natural Science Foundation of Ningbo City, China (201401A6105016, 2013A610126), and K. C.Wong Magna Fund in Ningbo University, China (NBUWC001).

摘要:

采用坩埚下降法生长了Tm3+掺杂浓度为0.45%,0.90%,1.63%与3.25%(摩尔分数,x)的LiLuF4单晶.测试了样品的电感耦合等离子体原子发射光谱(ICP-AES)、X射线衍射(XRD)谱、吸收光谱(1400-2000 nm),并且分析比较了808 nm半导体激光器(LD)激发下荧光光谱. 结果表明:当Tm3+的浓度从0.45%变化到3.25%时,1800 nm处的荧光强度呈现了先增后减的趋势,当掺杂浓度约为0.90%时达到最大值,而位于1470 nm处的荧光强度则呈现了相反的趋势. Tm3+3F4能级的荧光衰减寿命随着掺杂浓度的增加不断减小. 1800 nm处的这种荧光强度变化归结于Tm3+离子间的交叉驰豫效应(3H63H43F43F4)和自身的浓度猝灭效应. 同时计算得到了浓度为0.90%的样品在1890 nm处的最大发射截面为0.392×10-20 cm2. 并且根据Judd-Ofelt 理论所得寿命和测定的荧光寿命计算得到了3F43H6的最大量子效率约为120%.

关键词: Tm3+:LiLuF4单晶, 交叉驰豫, 荧光强度, 浓度猝灭

Abstract:

LiLuF4 single crystals doped with molar fractions of 0.45%, 0.90%, 1.63%, and 3.25% (x, molar fraction) Tm3+ ions were fabricated by an improved Bridgman method. Absorption spectra in the 400-2000 nm region of the crystals were measured. The emissions from 1400 to 2000 nm under excitation of an 808-nm laser diode (LD) were carried out and compared. Two emission bands at 1470 and 1800 nm were observed. First, the emission intensity at 1800 nm increased with the increase in Tm3+ concentration, reaching a maximum value when the Tm3+ concentration was ca 0.90%. Thereafter, it decreased considerably as the Tm3+ doping levels further increased to 3.25%. However, the emission intensity at 1470 nm showed the contrary tendency to that at 1800 nm. It was found that the 1800-nm emission lifetime of the Tm3+:3F4 manifold systematically decreased with an increase in Tm3+ concentration. The trend in the fluorescent intensity change can be explained by the cross-relaxation (3H6, 3H43F4, 3F4) between the Tm3+ ions and the concentration quenching effect of Tm3+. Meanwhile, the emission cross-section was calculated, providing a maximum of 0.392×10-20 cm2 at 1890 nm for the 0.90% doped sample. Based on the measured lifetime and calculated radiative lifetime, the largest quantum efficiency between Tm3+ ions reached ~120%.

Key words: Tm3+-doped LiLuF4 crystal, Cross-relaxation, Fluorescent intensity, Concentration quenching