摘要
贾德-奥菲尔特(Judd-Ofelt,J-O)理论是半定量地研究稀土离子掺杂基质中4f能级间跃迁光学性质的经典理论,但标准的贾德-奥菲尔特理论表达式本身含有一定的简化近似和假设,应用于Pr3+等具有特殊能级的稀土离子时会产生异常结果。制备了掺Pr3+和Tm3+的氟化镓铟玻璃,研究了玻璃的吸收光谱。应用标准的和改进后的贾德-奥菲尔特理论分别拟合得到了不同的贾德-奥菲尔特强度参量和跃迁振子强度。通过分析对比可知,“超敏感跃迁”是产生异常贾德-奥菲尔特理论计算的重要因素;当加入了“超敏感跃迁”所对应奇数项约化矩阵元后,运用改进的贾德-奥菲尔特理论可计算出氟化镓铟玻璃中Pr3+较合理的贾德-奥菲尔特强度参量,并可对Tm3+的振子强度参量进行更好的拟合。
Judd-Ofelt （J-O）theory is the classical theory which is used to semiquantitative study 4f energy levels transitions＇s spectroscopic properties of rare-earth ions doped materials. Because many approximations and assumptions were involved in standard J-O theory, there are some exceptional behaviors when it is used for special earth ions such as Pr^3＋. Pr^3＋-, Tm^3＋-doped fluorogallate glasses were fabricated and the absorption spectrum of these glasses were studied. According to standard and modified Judd-Oflet theories, the different J-O intensity parameters Ωλ and oscillator strengths of those glasses have been calculated. The results show the ＂hypersensitive transitions＂ play the important role in exceptional behaviors of J-O theory calculation. When the corresponding odd reduced matrix element of ＂hypersensitive transitions＂ is added, the Ωλ of Pr^3＋ in fluorogallate glass obtained from modified J-O theory are more reliable than other approaches; for the experimental oscillator strengths of Tm^3＋ , there is also a better fit by the modified J-O theory than other calculated ones.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2007年第7期1232-1238,共7页
Acta Optica Sinica
