摘要
通过甘氨酸燃烧法制备了Yb3＋／Li＋共掺的YzO。纳米颗粒，研究了940nm半导体激光器激发下的Yb3＋ 1μm附近的光致发光光谱，结果表明1pm附近的荧光峰在共掺Li＋的摩尔分数为5％时达到最强，比不掺杂Li＋离子时增强了大约12倍。分析了X射线主衍射峰的移动，结果表明Li＋离子的掺杂改变了Yb3＋离子的晶体场环境。求解了稳态速率方程，结果表明荧光增强的主要原因是掺杂的Li＋离子扰乱了发光中心Yb3＋离子在Y2O3晶格中的环境，打破了发光跃迁选律，致使4f组态内电偶极跃迁增强，电偶极跃迁振子强度增大，从而导致基态吸收截面的增大。
Y2O3 nanoparticles codoped with Yb3＋/Li＋ ions are synthesized by glycine combustion method. Codoping with 5% mole fraction of Li＋ ions leads to about 12 times enhancement of the photoluminescence （PL） intensity around 1 μm under diode laser excitation of 940 nm. The movements of the X-ray main diffraction peak indicate that the codoping of Li＋ ions changes the lattice environment of Yb3＋ ions. Theoretical investigations based on the steady- state rate equations indicate that the PL enhancement arises mainly from the increased ground state absorption cross section of Yb3＋ ions by codoping with Li＋ ions. The codoping of Li＋ ions can disturb the local crystal field around the Yb3＋ ions in Y2O3 crystals, change the PL transition selection rules of Yb3＋ ions, resulting in enhanced intra-4f electric-dipole transitions and oscillator strength, which leads to the increase of ground state absorption cross section.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2013年第F06期237-240,共4页
Acta Optica Sinica
基金
广东省高校优秀青年创新人才培养计划（育苗工程）（2012LYM-0131）资助课题.
关键词
材料
稀土离子
光致发光
跃迁选律
速率方程
materials
rare earth ions
photoluminescence
transition selection rule
rate equations
