高折射率Nd,La共掺杂氧化钇透明陶瓷的光谱性质及其Judd-Ofelt理论分析

采用液相法和真空烧结技术制备了2.0%Nd,3.0%La共掺杂Y2O3透明陶瓷样品.样品晶粒均匀,大小在22μm左右,在晶粒和晶界处都未见气孔.元素线扫描结果表明,Nd离子和La离子均匀地分布于陶瓷晶粒和晶界处.并测试了样品的吸收光谱和荧光光谱.样品在主吸收峰821nm处的吸收截面为4.3×10-24m2,主荧光发射峰位于1078nm处,实测荧光寿命为0.287ms.采用Judd-Ofelt理论计算了Nd3+在掺La氧化钇陶瓷晶体场中的强度参数Ωλ(λ=2,4,6),自发辐射概率、辐射寿命、荧光分支比等光谱参数.通过F-L公式计算得到2.0%Nd,3.0%La共掺杂Y2O3透明陶瓷中Nd3+的4F3/2→4I11/2跃迁对应的受激发射截面大小为2.0×10-24m2.结果表明,La离子的掺入可以调节氧化钇透明陶瓷的晶体场,有助于制备符合实际需求的固体激光器材料.

Spectroscopic properties and Judd-Ofelt theory analysis of La, Nd codoped Y_2O_3 high refractivity transparent ceramics

Nd, La:Y_2O_3 nanocrystaUine powder was prepared by co-precipitation method. The transparent ceramic was fabricated by vacuum sintefing at 1700℃ for 4 h in vacuum. Transparent polyerystalline ceramics with uniform lanthanum distribution was obtained. The grain size was around 22 μm. No pores were found in the grain and grain boundary. The absorption spectrum and the fluorescence spectrum of the sample were measured. The highest absorption peak is centered at 821 nm and the absorption cross section is 4.3 × 10~(24)m~2. The main emission peak is at 1078 rim, and the fluoreseenee lifetime is 0.287 ms. The Judd-Ofelt intensity parameter Ω_λ(λ = 2,4,6), spontaneous transition probability, radiative lifetime and fluorescence branching ratio of Nd~(3+) were calculated by Judd-Ofelt theory. The calculated emission cross section Of ~4F_(3/2)→~4_(11/2) transition is 2.0 ×10~(-24) m~2. It was found that the addition of La ion can change the crystalline field of yttria, which helps to obtain suitable solid laser materials.