摘要
InAs/GaSb Ⅱ型超晶格是中红外谱段光电子器件的核心结构,其Ⅱ型能带排列特点使电子、空穴在实空间分离而跨过界面,其非公共原子构型使得界面态丰富。我们在Burt-Foreman包络函数理论的基础上,讨论了不同界面态对超晶格电子能态和波函数的调控作用。理论计算表明,超晶格缓变界面和界面势两种不对称界面态分布,都会导致重空穴带的自旋劈裂,而只有施加界面势时才会使得轻空穴带发生自旋劈裂。此外,研究了改变阱宽和改变势垒时超晶格体系带隙的变化趋势。结果表明,随着势垒厚度增大,陡峭界面和缓变界面两种界面态下的带隙计算结果逐渐降低,并且随着厚度增加带隙趋于收敛,而界面势下的带隙计算结果随着势垒厚度的增大而增大,与前两者呈现相反的趋势,这为中红外超晶格器件的精确设计提供了可参考的理论基础。
The InAs/GaSb type-Ⅱsuperlattice(SL)constitutes the fundamental structure for mid-infrared optoelectronic devices,characterized by its type-Ⅱband alignment that facilitates the spatial separation of electrons and holes across the interface,and a unique atomic configuration leading to a rich variety of interface states.Building upon the Burt-Foreman envelope function theory,we investigate the influence of different interface states on the electronic states and wave functions of the superlattice.Theoretical calculations indicate that both asymmetric distributions of interface states,namely gradual interface variation and interface potential,result in spin splitting of the heavy-hole band,while spin splitting in the light-hole band occurs only with the application of an interface potential.Additionally,we examine the trends in the band gap of the superlattice system when altering well width and barrier height.The results show that as the barrier thickness increases,the gap calculations under both abrupt and gradual interface states gradually decrease,converging with increasing thickness.In contrast,the gap calculated with interface potential treatment increases with the thickness of the barrier,exhibiting an opposite trend to the former two.This provides a theoretical foundation for the precise design of mid-infrared superlattice devices.
作者
马泽军
李远
朱申波
程凤敏
刘俊岐
王利军
翟慎强
卓宁
陈涌海
张锦川
刘舒曼
刘峰奇
MA Zejun;LI Yuan;ZHU Shenbo;CHENG Fengmin;LIU Junqi;WANG Lijun;ZHAI Shenqiang;ZHUO Ning;CHEN Yonghai;ZHANG Jinchuan;LIU Shuman;LIU Fengqi(Laboratory of Solid-State Optoelectronics Information Technology,Institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,China;College of Materials Science and Opto-Electronic Technology,University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《发光学报》
EI
CAS
CSCD
北大核心
2024年第5期817-823,共7页
Chinese Journal of Luminescence
基金
国家自然科学基金(12393832,62327813,62235019,62235016,61991431)。
关键词
锑化物
超晶格
界面态
前后向差分法
antimonide
superlattice
interface state
forward and backward difference method
