摘要
利用居地-奥非脱(Judd-Ofelt)[2,3]理论计算了Er3+离子在氟化钇锂(LiYF4简写为YLF)晶体中的辐射跃迁几率AJJ′,无辐射跃迁几率ωJJ′及激发态荧光寿命τJ,并根据荧光动力学方程计算出各激发态布居数NJ与掺杂浓度x的关系。对2.7μm激光(4I11/2→4I13/2)来说,掺杂浓度要大于~3at.%,才能实现布居数反转,对波长为1.73μm的4I13/2→4I15/2跃迁,存在荧光强度最大的掺杂浓度xop,在泵浦几率为103~105s-1范围内,xop为1.8~3.0at.%。文中还计算了ErYAG晶体的光谱特征参数。
The radiative transition probabilities A JJ′ , nonradiative transition probabilities ω JJ′ and fluorescence lifetimes τ J of excited levels of Er 3+ ions in YLF crystal are calculated by using the Judd Ofelt theory. On the basis of equations of fluorescent dynamics the populations w J of excited levels, dependented on doped concentrations x, are calculated too. For 4I 11/2 → 4I 13/2 transition (at wavelength of 2.7 μm), only if doped concentration is bigger than 3 at.% the population inversion can be, and the fluorescence strength and doped concentration are increased. But for 4I 13/2 → 4I 15/2 transition (at wavelength of 1.73 μm), there is a optimal doped concentration for which the fluorescent strength is maximal. When the pump probabilty is 10 3 ̄10 5 s -1 , the x op is 1.8 ̄3.0 at.%. The spectral characteristic parameters of Er 3+ ions in YAG crystal are calculated. Based on the comparison the advantages of Er 3+ ∶YLF as a laser crystal are discussed.
出处
《光学学报》
EI
CAS
CSCD
北大核心
1996年第12期1708-1713,共6页
Acta Optica Sinica
基金
浙江省自然科学基金