应变GaN/Al_xGa_(1-x)N柱形量子点中杂质态的结合能  

Binding energy of the impurity state in a strain GaN/Al_xGa_(1-x)N cylindrical quantum dot

作　　者：张冬[1] 闫祖威[1,2] 

机构地区：[1]内蒙古大学物理科学与技术学院,呼和浩特010021 [2]内蒙古农业大学理学院,呼和浩特010018

出　　处：《内蒙古大学学报（自然科学版）》2010年第3期289-296,共8页Journal of Inner Mongolia University：Natural Science Edition

基　　金：国家自然科学基金资助项目(10964006);教育部科学技术研究重点资助项目(208025)

摘　　要：在有效质量近似下,利用变分原理研究了有限高应变GaN/AlxGa1-xN柱形量子点中杂质态的结合能,计算了结合能随量子点高度、半径和杂质位置的变化,讨论了应变对结合能的影响.数值计算表明,杂质态结合能随量子点半径的增大而减小,随量子点高度的增加将先增大到一极大值然后减小.当杂质位置在量子点中心时杂质态的结合能最大,且Al组分的增加使杂质态的结合能增大.研究还指出内建电场使得杂质态的结合能明显降低.Within the effective-mass approximation,the binding energy of a hydrogenic donor impurity state is investigated in a finite-potential GaN/AlxGa1-xN cylindrical quantum dot via a variational approach.The binding energies as functions of the height,radius of the quantum dot and location of the impurity are calculated.The strain influence on binding energies is also discussed.Numerical results show that the binding energy decreases with increasing the radius while increases to a maximum then decreases as the height increases.When the impurity locates in the center of the quantum dot,the binding energy reaches a peak value.Besides,the increase of Al concentration can enhance the binding energy.It is also found that the built-in electric field evidently reduces the binding energy.

关 键 词：量子点 类氢杂质 内建电场 结合能 

分 类 号：O471.3[理学—半导体物理]