纤锌矿GaN/Al_xGa_(1-x)N应变柱形量子点中杂质态结合能及其压力效应  

Binding Energies of Impurity States in a Strained Wurtzite GaN/Al_xGa_(1-x)N Cylindrical Quantum Dot Influenced by Hydrostatic Pressure

作　　者：张文强[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,内蒙古呼和浩特010021 [2]内蒙古农业大学理学院,内蒙古呼和浩特010018

出　　处：《发光学报》2011年第2期115-121,共7页Chinese Journal of Luminescence

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

摘　　要：考虑应变及流体静压力,在有效质量近似下,利用变分法计算了无限高GaN/AlxGa1-xN应变柱形量子点中类氢杂质结合能。结果表明,在量子点尺寸较小情况下,应变增加了杂质态结合能;而在量子点尺寸较大情况下,应变降低了杂质态结合能。随着Al摩尔分数的增加,杂质态结合能减小。杂质态结合能随着流体静压力的增加而增大,在量子点尺寸较小的情况下,流体静压力对杂质态结合能的影响更明显。In the framework of effective mass approximation, a variational method is adopted to discuss the binding energies of hydrogenic impurity in a strained wurtzite cylindrical quantum dot by considering the hydrostatic pressure. The results indicate that the binding energies of hydrogenic impurity with strain effect are higher than that without strain effect when the quantum dot height is small, but the bindin effect become lower than that without strain effect as the quantum dot height increases. It g energies with strain is also found that the binding energies of hydrogenic impurity decrease when the mole fraction of A1 increase. In addition, the binding energies of impurity increase obviously with hydrostatic pressure, and the hydrostatic pressure has a remarkable influence on the donor binding energy for small quantum dot.

关 键 词：量子点 类氢杂质 应变 流体静压力 

分 类 号：O471.3[理学—半导体物理]