摘要
利用嵌入原子簇模型结合F心的类H离子波函数研究了α-Al2O3晶体中F3聚集型色心存在时,晶体的能带结构,态密度,Muliken电荷布居的变化,讨论了色心的光学吸收跃迁模式。结果表明,由于F3聚集心的存在,在α-Al2O3中引入了1个单能级和1个2重简并色心能级,产生了一个3.54eV的从色心能级到导带底的新的吸收跃迁。经与高能量,大注量中子辐照后的刚玉晶体的光学吸收实验结果比较,我们认为实验测得的0.356μm(3.483eV)处的吸收峰是由于F3聚集心的电子的吸收跃迁所引起的。同时,也发现F3聚集心的格点处的电荷布居比单F心格点处的电荷布居小。
This paper study the various of energy band structure,density of state, Mulliken charge density when the F 3-center is in the alumina by using the embedded-cluster of Al 2O 3 and H-like wave function of F-center,also discuss the optical transition models of color center.We find existing one single energy level and one doubly-degenerate energy level in the fundamental gap when the F 3-center in the crystal,and there is a new 3.54 eV transition from defect energy level to condition band.Comparing with the absorption spectrum of alumina by high-energy and great flux neutron radiation,we think that the 0.356 μm(3.483 eV)absorption peak is due to the F 3-center. Also,we find the charge density is more little in the site of F 3-center Than F-center in alumina crystal.
出处
《原子与分子物理学报》
CSCD
北大核心
1999年第2期211-216,共6页
Journal of Atomic and Molecular Physics