Gd^(3+)/Y^(3+)共掺对Nd:CaF_2晶体光谱性能的影响  

Effects of Gd^(3+)/Y^(3+) codoping on the spectral properties of Nd:CaF_2 crystals

作　　者：刘坚[1,2] 刘军芳[1] 苏良碧[2] 张倩[2] 马凤凯[2] 姜大朋[2] 徐军[3] 

机构地区：[1]同济大学材料科学与工程学院,上海201802 [2]中国科学院上海硅酸盐研究所,上海201809 [3]同济大学物理科学与工程学院,上海200092

出　　处：《物理学报》2016年第5期144-150,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61178056;61422511;61008045);材料复合新技术国家重点实验室(武汉理工大学)开放基金(批准号:2015-KF-10)资助的课题~~

摘　　要：通过坩埚下降法生长了系列共掺Nd,Gd:CaF_2和Nd,Y:CaF_2晶体,研究了Gd^(3+)/Y^(3+)共掺对Nd^(3+)光谱性能以及Nd:CaF_2晶体晶胞参数的影响规律.对于0.5 at.%Nd,x at.%Gd(x=2,5,8,10):CaF_2系列晶体,当调控Gd^(3+)掺杂浓度为2 at.%时,具有最大的荧光寿命499μs;当Gd^(3+)掺杂浓度为5 at.%时,具有最大的吸收截面1.47×10^(-20)cm^2,最大的发射截面1.9×10^(-20)cm^2;当Gd^(3+)掺杂浓度为8 at.%时,具有最佳的发射带宽29.03 nm.对于0.6 at.%Nd,x at.%Y(x=2,5,8,10):CaF_2系列晶体,Y^(3+)掺杂浓度为5 at.%时,有最大的吸收截面2.41×10^(-20)cm^2,最大的发射截面3.17×10^(-20)cm^2;当Y^(3+)掺杂浓度为10 at.%时,具有最长的荧光寿命359.4μs,并且具有最大发射带宽26 nm.In the last few years,Nd^3＋ doped fluoride crystals have achieved some amazing laser performances by codoping buffer ions such as Y^3＋ and Gd^3＋ ions,which lead to the changing of local structure of Nd^3＋ ions.In this work,effects of doping concentration of Gd^3＋ and Y^3＋ 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.Among 0.5 at.%Nd,x at.%Gd（x=2,5,8,10）：CaF2 crystals,the crystal with Gd^3＋ of 2 at.%has the longest fluorescence lifetime（499（μs）.Increasing the concentration of Gd^3＋ up to 5at.%,the crystal has a maximum absorption cross section of 1.9×10^-20 cm^2,and a maximum emission cross section of1.9×10^-20 cm^2.The crystal with Gd^3＋ of 8 at.%has a maximum emission bandwidth of 29.03 nm（FWHM）.Among0.6 at.%Nd,x at.%Y（x = 2,5,8,10）：CaF2 crystal,the crystal with Y^3＋ of 5 at.%has the biggest absorption cross section（2.41×10^-20 cm^2）,and the biggest emission cross section（3.17×10^-20 cm^2）,when the concentration of Y^3＋ is5 at.%.When the Y^3＋ concentration increases up to 10 at.%,the crystal has a longest fluorescence lifetime of 359.4 μs 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 Nd^3＋ on the optical properties in a set of Nd：CaF2 single crystals with different codoping concentrations of Gd^3＋ and Y^3＋,the unit cell parameters are investigated by X-ray diffraction.With different concentrations of Gd^3＋ and Y^3＋ ions in Nd：CaF2 crystal,the local structure of Nd^3＋ changes,which leads to different optical properties.The relevant details will further be explained in this paper.

关 键 词：Nd:CaF2晶体 调控离子 晶胞参数 光谱性能 

分 类 号：O734[理学—晶体学]