【摘要】 利用有效质量方法和变分原理,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GaN/A lxGa1-xN柱形量子点中类氢杂质的结合能随量子点高度、A l含量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,杂质结合能随量子点高度的增加先增大后减小,存在最大值;随着A l含量的增加,杂质结合能增大。而杂质从量子点下界面沿Z轴上移至上界面时,杂质结合能先增大后减小,存在最大值。更多还原

【Abstract】 In this paper,we investigate the binding energy of a hydrogenic-like impurity as function of the height of QDs,Al content and the hydrogenic-like impurity position for an cylindrical wurtzite GaN/Al_xGa_1-xN 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.With increasing Al content, the binding energy of hydrogenic-like impurity increases.The dependence of binding energy on the impurity-center position is also considered.The binding energy of hydrogenic-like impurity firstly increases,and then decreases with moving the impurity position from the bottom of QD to the top.There is a maximum.更多还原