Cr∶Nd∶YCa_4O(BO_3)_3光谱参数的计算

Optical Parameters of Cr∶Nd∶YCa_4O(BO_3)_3 Crystal

采用Czochralski法生长了透明均匀的Cr∶Nd∶YCaO(BO3) 3晶体 ,生长的晶体尺寸为4 2 .5×50mm ,生长参数为提拉速度为 0 .6mm/h ,转速为 2 5r/min。测定了其室温吸收谱。根据Judd -Ofelt理论拟合了Nd3+ 离子的强度参数Ωλ:Ω2 =0 .734× 10 - 2 0 ,Ω4 =6 .814× 10 - 2 0 ,Ω6 =2 .4 76× 10 - 2 0 ;并计算了各能级跃迁的自发辐射跃迁几率、辐射寿命、荧光分支比。其中4 F3/2 能级的寿命τtot=2 71.6 4 μs,4 F3/2 →4 I9/2 的荧光分支比 βc=58.0 1%。并对实验结果进行了讨论。

The transparent and homogeneous Cr∶Nd∶YCa 4O(BO 3) 3 (Cr∶Nd∶YCOB) crystal is grown by Czochralski method.The crystal grown size is 42.5mm in diameter and 59mm long.The growth parameters of Cr∶Nd∶YCOB crystal are:the pulling rate is 0.6mm/h and the rotation rate is 25r/min.The room temperature absorption spectra are measured.The optical parameters of Cr∶Nd∶YCOB crystal were calculated by following Judd Ofelt theory.The three optical parameters are Ω 2=0.734×10 -20 , Ω 4=6.814×10 -20 , Ω 6=2.476×10 -20 (REM=1.4×10 -21 );and the total transition rate of 4 F 3/2 level is 271.64μs,the branching ratio β( 4 F 3/2 → 4 I 9/2) is 58.01%.The result of this experiment is discussed.