摘要
以高纯α-Al2O3、Y2O3、Nd2O3和Cr2O3粉体为原料,CaO为电荷补偿剂,正硅酸乙酯(TEOS)为烧结助剂,采用固相反应法和真空烧结技术成功制备了高质量的Cr4+,Nd3+∶YAG透明陶瓷。研究了其在室温下的吸收光谱和发射光谱性质,0.1%Cr,1.0%Nd∶YAG(Cr,Nd为摩尔分数,下同)透明陶瓷在808nm处的吸收截面为4.27×10-20cm2,1064nm处的发射截面和荧光寿命分别为1.52×10-20cm2和206μs。由Cr4+,Nd3+∶YAG透明陶瓷的吸收和发射光谱计算出的吸收和发射截面,进一步估算了材料的激光性能参数,并对其激光性能进行理论预测。Cr,Nd∶YAG透明陶瓷很可能是一种具有潜力的自调Q激光材料。
Cr^4 ＋ -doped YAG （Y3Al5O12） crystal is an ideal material used for passive-Q-switch, especially used in high power and high repetition rate lasers. Nd^3＋ -doped YAG crystal is the best gain medium at present. ceramics Since 1995 Ikesue et al. firstly demonstrated the possibility of fabricating transparent Nd： YAG of sufficient quality for solid-state lasers, polycrystalline ceramic laser materials have attracted much attention because the optical quality has been improved greatly and highly efficient laser output could be obtained whose efficiencies are comparable or superior to those of single crystal. The purpose of the work is to combine the advantages of the gain medium Nd^3＋ and the saturable absorber Cr^4＋ using ceramic technology. The transparent Cr^4＋ , Nd^3＋ ： YAG ceramics were fabricated by a solid-state reaction and vacuum sintering with CaO as a charge compensator, tetraethyl orthosilicate （TEOS） as a sintering aid and high-purity α-Al2O3, Y2O3, Nd2O3 and Cr2O3 powders as starting materials. The absorption spectra, fluorescence spectra and fluorescence of the 0.1% Cr, 1.0% Nd： YAG transparent ceramics were measured at room temperature. For the Cr^4＋, Nd^3 ＋ ： YAG transparent ceramic sintered at 1 800 ℃ for 30 h, the absorption cross section, is 4.27 × 10^-20 cm^2 at 808 nm, emission cross section and fluorescence lifetime are 1.52 × 10^-20 cm^2 and 206 μs at 1 064 nm, respectively. The laser performance parameters of the gained Cr^4＋ , Nd^3＋ ： YAG transparent ceramic were evaluated by Isat,βmin and Imin. based on the spectroscopic parameters. The pump saturation intensity parameter Isat, the βmin parameter which is defined as the minimum inversion fraction of Nd^3＋ ions that must be exited to balance the ions exactly with the ground-state absorption at the extraction wavelength, and the minimum absorption pump intensity Imin to reach the threshold at the extraction wavelength are 28.0 kW/cm^2, 52.2% and 14.6 kW/cm^2, respectively. High-quality Cr^4＋ ,
出处
《发光学报》
EI
CAS
CSCD
北大核心
2007年第2期219-224,共6页
Chinese Journal of Luminescence
基金
上海市科委光科技项目(05DZ22005)
上海市科委基础研究重大项目(04DZ14002)资助项目
关键词
CR
ND:YAG透明陶瓷
光谱性质
激光性能参数
自调Q激光
Cr, Nd： YAG transparent ceramics
spectroscopic properties
laser performance parameters
self-Q-switched laser
