摘要
为了研究InAs/InAs1-xSbxⅡ类超晶格结构的物理特性,首次采用全原子的经验赝势方法对InAs/InAs1-xSbx结构进行模拟,并对体系的近带边能级、单粒子波函数和带边跃迁矩阵元进行了计算。结果表明,量子限制效应造成超晶格带隙的宽化;超晶格中基态电子主要局域在InAs层,基态空穴主要局域在合金层,与相关体材料及I型超晶格所做的对比结果表明,电子、空穴的物理分离效应是造成体系载流子寿命较长的重要原因;将带边跃迁矩阵元作为衡量载流子寿命的重要元素,针对固定波段的超晶格系统进行优化,最终得到带边跃迁矩阵元更小的体系(163?) InAs/(82?) InAs0. 72Sb0. 28结构,其跃迁矩阵元是0. 010 684 3 a.u.。
In order to study the physical properties of the InAs/InAs 1-xSbx type-Ⅱsuperlattice,the superlattice structure of the core part was simulated for the first time by the all-atoms empirical pseudopotential method.The near band edge levels,single particle wave functions and band edge transition matrix of the system were calculated.The results show that the quantum confinement effect leads to the broadening of the band gap in the superlattice.The ground state electrons in the superlattice are mainly localized in the InAs layer while the ground state holes are mainly in the alloy layer.By comparing with the related materials and the type-Ⅰsuperlattice,it is pointed out that the electron-hole physical separation effect is an important reason for the longer carrier life of the system.The band edge transition matrix element was used as the quality factor to measure the carrier lifetime,and the system of the fixed band superlattice was optimized.Finally,the system(163A)InAs/(82A)InAs 0.72 Sb 0.28,which has smaller band edge transition matrix elements,is obtained.The transition matrix element is 0.010 684 3 a.u.
作者
马玲丽
詹锋
MA Ling-li;ZHAN Feng(Key Laboratory of Nonferrous Metal Materials andNew Processing Technology of Ministryof Education,School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China)
出处
《广西大学学报（自然科学版）》
CAS
北大核心
2018年第6期2462-2469,共8页
Journal of Guangxi University（Natural Science Edition）
基金
广西自然科学基金资助项目(2014GXNSFAA118025)。
关键词
Ⅱ型超晶格
全原子经验赝势
跃迁矩阵元
type-Ⅱsuperlattice
all-atom empirical pseudopotential method
transition matrix element
