关键词: Nd:CaF2晶体/
调控离子/
晶胞参数/
光谱性能
English Abstract
Effects of Gd3+/Y3+ codoping on the spectral properties of Nd:CaF2 crystals
Liu Jian1,2,Liu Jun-Fang1,
Su Liang-Bi2,
Zhang Qian2,
Ma Feng-Kai2,
Jiang Da-Peng2,
Xu Jun3
1.School of Materials Science and Engineering, Tongji University, Shanghai 201802, China;
2.Key Laboratory of Transparent and Opto-functional Inorganic Materials, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 201809, China;
3.School of Physics Science and Engineering, Institute for Advanced Study, Tongji University, Shanghai 200092, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant Nos. 61178056, 61422511, 61008045) and the Key Laboratory of Advanced Technology for Materials Synthesis and Processing (Wuhan University of Technology), China (Grant No. 2015-KF-10).Received Date:24 September 2015
Accepted Date:11 November 2015
Published Online:05 March 2016
Abstract:In the last few years, Nd3+ doped fluoride crystals have achieved some amazing laser performances by codoping buffer ions such as Y3+ and Gd3+ ions, which lead to the changing of local structure of Nd3+ ions. In this work, effects of doping concentration of Gd3+ and Y3+ ions on optical properties are discussed. The relationships between spectroscopic properties and the unit cells are also discussed. Nd, Y:CaF2 and Nd, Gd:CaF2 disordered crystals are grown by using temperature gradient technique (TGT). Among 0.5 at.%Nd, x at.%Gd(x=2, 5, 8, 10):CaF2 crystals, the crystal with Gd3+ of 2 at.% has the longest fluorescence lifetime (499 s). Increasing the concentration of Gd3+ up to 5 at.%, the crystal has a maximum absorption cross section of 1.910-20 cm2, and a maximum emission cross section of 1.910-20cm2. The crystal with Gd3+ of 8 at.%has a maximum emission bandwidth of 29.03 nm(FWHM). Among 0.6 at.%Nd, x at.%Y(x=2, 5, 8, 10):CaF2 crystal, the crystal with Y3+ of 5 at.%has the biggest absorption cross section (2.4110-20 cm2), and the biggest emission cross section (3.1710-20 cm2), when the concentration of Y3+ is 5 at.%. When the Y3+ concentration increases up to 10 at.%, the crystal has a longest fluorescence lifetime of 359.4 s and maximal emission bandwidth of 26 nm(FWHM).The different concentrations of codoping ions have different effects on the Nd:CaF2 crystals, for the formations of different optical centers. In order to study the effects of local structure around Nd3+ on the optical properties in a set of Nd:CaF2 single crystals with different codoping concentrations of Gd3+ and Y3+, the unit cell parameters are investigated by X-ray diffraction. With different concentrations of Gd3+ and Y3+ ions in Nd:CaF2 crystal, the local structure of Nd3+ changes, which leads to different optical properties. The relevant details will further be explained in this paper.
Keywords: Nd:CaF2 crystal/
buffer ions/
unit cell parameters/
spectrum properties
