In_xGa_(1-x)N/GaN量子点中类氢杂质态结合能  

Binding Energy of a Hydrogenic-like Impurity in In_xGa_(1-x)N/GaN Quantum Dots

作　　者：郑冬梅[1] 戴宪起[2] 

机构地区：[1]三明学院物理与机电工程系,福建三明365004 [2]河南师范大学物理与信息工程学院,河南新乡453007

出　　处：《三明学院学报》2008年第2期144-148,共5页Journal of Sanming University

摘　　要：在有效质量近似下,运用变分方法,考虑内建电场(BEF)效应和量子点的三维约束效应,研究了纤锌矿结构的InxGa1-xN/GaN柱形量子点中类氢杂质态结合能随量子点的结构参数(高度、半径)I、n组分和杂质位置的变化规律。结果表明:类氢杂质位于量子点中心时,杂质态结合能随量子点高度的增加先增大后减小,存在最大值;随量子点半径增大而减小;而随着In组分的增加,杂质态结合能增大;杂质从量子点下界面沿z轴移至上界面过程中,杂质态结合能增大;量子点内外材料的电子有效质量的失配使杂质态结合能减小。In this paper, we investigate the binding energy of a hydrogenic-like impurity as function of the structural parameters of QDs （height and radius）, In content and the hydrogenic-like impurity position for an cylindrical wurtzite InxGa1-xN/GaN QD within the framework of effective-mass approximation and a variational approach, including three-dimensional confinement in QDs and a strong built-in electric field effect. The numerical results show that when the hydrogenic-like impurity in the center of QDs, the binding energy first increases rapidly, reachs a maximum value, then slowly decreases with increasing the height of QDs. the binding energy decreases with increasing the radius of QDs.With increasing In content, the binding energy of hydrogenic-like impurity slowly increases. The dependence of binding energy on the impurity-center position is also considered. The binding ener- gy of hydrogenic-like impurity increases with moving the impurity position from the bottom of QD to the top. The inside and outside of QDs, the electronic effective-mass mismatch of the material makes binding energy of impurity state decrease.

关 键 词：类氢杂质态 InxGa1-xN/GaN量子点 结合能 

分 类 号：O474[理学—半导体物理]