AlAs/InSe范德华异质结构的光学和可调谐电子特性  

Optical and Tunable Electronic Properties of AlAs/InSe Van Der Waals Heterostructures

作　　者：郭瑞 魏星 曹末云 张研[1] 杨云[2] 樊继斌[1] 刘剑[3] 田野[4] 赵泽坤 段理[1] Guo Rui;Wei Xing;Cao Moyun;Zhang Yan;Yang Yun;Fan Jibin;Liu Jian;Tian Ye;Zhao Zekun;Duan Li(School of Materials Science and Engineering,Chang’an University,Xi’an 710061;School of Information Engineering,Chang’an University,Xi’an 710061;School of Physics,Shandong University,Jinan 250100;Institute of Physics,Chinese Academy of Sciences,Beijing 100190)

机构地区：[1]长安大学材料科学与工程学院,西安710061 [2]长安大学信息工程学院,西安710061 [3]山东大学物理学院,济南250100 [4]中国科学院物理研究所,北京100190

出　　处：《化学学报》2022年第4期526-534,共9页Acta Chimica Sinica

基　　金：项目国家重点研发计划(No.2018YFB1600200);国家自然科学基金(No.51802025);陕西省自然科学基础研究计划(No.2019JQ-676);陕西省国际科技合作计划重大项目(No.2020KWZ-008)资助。

摘　　要：由不同二维(2D)材料相互堆叠形成异质结构已成为目前的研究热点,使用第一性原理的计算方法探究了AlAs/In Se异质结构的几何结构、电子性能和光学性质.结果表明,AlAs/InSe异质结构具有典型的Type-Ⅱ型能带排列并且拥有着1.28eV的间接带隙.通过调节层间距或施加外部电场和应变,可以有效地改变异质结构的带隙值.有趣的是,当应用5 V/nm的电场时,异质结构实现了从Type-Ⅱ向Type-Ⅰ的转变.此外,与孤立单层相比,AlAs/InSe异质结构的吸光度明显提高,特别是在紫外区域.表明新型的二维AlAs/In Se异质结可以作为光电材料和紫外探测器件的有力候选者.The formation of heterostructures from different two-dimensional(2D) materials stacked on top of each other has become a current research hotspot.Heterojunctions can retain the characteristics of their constituent materials and produce new characteristics.Stacking AlAs monolayers on InSe monolayers to form AlAs/InSe heterojunctions is an effective way to improve the defects of its constituent materials.This project is based on density functional theory,using the first-principles plane wave ultra-soft pseudo-potential method to calculate the geometric structure,electronic properties and optical properties of AlAs/InSe heterostructures.By changing the stacking method of the heterojunction and adjusting the distance between layers,the most stable theoretical model is found.The density of states(DOS) and energy band gap are calculated,and the properties of AlAs/InSe heterojunction are analyzed by applying external conditions.The results show that the AlAs monolayer has an indirect band gap of 1.88 eV,the InSe monolayer has an indirect band gap of 2.02 eV,and the band gap of the AlAs/InSe heterostructure is significantly reduced,with a value of 1.28 eV and typical Type-Ⅱ band arrangement.When the layer spacing is adjusted or an external electric field and strain are applied,the band gap value of the heterostructure can be effectively changed.Interestingly,when an electric field of 5 V/nm is applied,the heterostructure realizes the transition from Type-Ⅱ to Type-I.And when the electric field intensity continues to increase,AlAs/InSe heterojunction can complete the transition from semiconductor to metal.At the same time,it is found that a similar situation occurred in the heterojunction when strain was applied.Taking into account the underestimation of the semiconductor band gap by the Perdew-BurkeErnzerhof(PBE) functional,the Heyd-Scuseria-Ernzerhof(HSE06) hybrid functional is used to calculate the optical properties and obtain more accurate results.Compared with the isolated monolayer,the absorbance of the AlAs/In

关 键 词：AlAs/InSe异质结 第一性原理计算 Type-Ⅱ型能带排列 电场 应变 

分 类 号：TB34[一般工业技术—材料科学与工程]