【摘要】 采用Czochralski法生长出光学质量的BaWO4:Tm3+单晶,利用X粉末衍射实验确定了不同掺杂浓度晶体的晶胞参数.测定了晶体的室温吸收光谱,应用Juud-Ofelt理论,拟合了光谱的3个强度参数,其值分别为Ω2=4.04×10-20cm2,Ω4=0.509×10-20cm2,Ω6=0.134×10-20cm2,计算了光学参数,如各个能级跃迁的谱线强度、振子强度、吸收截面,得到荧光寿命、荧光分支比和受激发射截面.测定了紫外可见荧光谱,分析了可能的发光机理.在钛宝石激光和LD激光激发时,室温下观察到BaWO4:Tm3+晶体的红色上转换发光,相应于3F3到3H6的能级跃迁.更多还原

【Abstract】 The BaWO4:Tm3+ single crystals of optical quality have been grown by the Czochralski technique. The lattice parameters of crystals with different doping concentrations were determined by XRD. The absorption spectra were measured at room temperature. And the optical parameters,such as transition line intensity,oscillator strength and absorption section were calculated by using Juud-Ofelt theory. The three intensity parameters were fitted to be Ω2=4.04×10-20cm2,Ω4=0.509×10-20cm2,Ω6=0.134×10-20cm2,respectively. The lifetime,branching ratio and integrated stimulated-emission cross section were obtained. Ultra-visible fluorescence was measured and analyzed. The red up-conversion luminescence with wavelengths 689 nm and 704 nm corresponding to the transition from 3F3 to 3H6 was observed under Ti-sapphire laser and LD laser,respectively.更多还原