物理化学学报 >> 2012, Vol. 28 >> Issue (12): 2845-2851.doi: 10.3866/PKU.WHXB20121083

理论与计算化学 上一篇    下一篇

ZnSe掺Cu与Zn空位缺陷的稳定性、电子结构与光学性质

郭雷, 胡舸, 张胜涛   

  1. 重庆大学化学化工学院, 重庆 400044
  • 收稿日期:2012-08-22 修回日期:2012-10-08 发布日期:2012-11-14
  • 通讯作者: 胡舸 E-mail:cqhuge@163.com
  • 基金资助:

    中央高校基本科研业务费(CDJZR11220003)资助项目

Defects Energetics, Electronic Structure and Optical Properties of Cu-Doping and Zn Vacancy Impurities in ZnSe

GUO Lei, HU Ge, ZHENG Sheng-Tao   

  1. College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, P. R. China
  • Received:2012-08-22 Revised:2012-10-08 Published:2012-11-14
  • Supported by:

    The project was supported by the Fundamental Research Funds of the Central Universities, China (CDJZR11220003).

摘要:

采用基于密度泛函理论框架下的第一性原理平面波超软雁势方法, 对ZnSe闪锌矿结构本体、掺入p型杂质Cu(Zn0.875Cu0.125Se)及Zn空位(Zn0.875Se)超晶胞进行结构优化处理. 计算并详细分析了缺陷体系的形成能和三种体系下ZnSe材料的态密度、能带结构、集居数、介电和吸收光谱. 结果表明: 在Zn空位与Cu掺杂ZnSe体系中, 由于空位及杂质能级的引入, 禁带宽度有所减小, 吸收光谱产生红移; 单空位缺陷结构不易形成, Zn0.875Se结构不稳定, Cu掺杂ZnSe结构相对更稳定.

关键词: 硒化锌, 空位缺陷, Cu掺杂, 电子结构, 光学性质, 第一性原理

Abstract:

Based on first-principles within the density functional theory, the geometric structures of perfect zinc blend ZnSe, that with Zn vacancies (Zn0.875Se) and Cu-doped ZnSe(Zn0.875Cu0.125Se) were optimized using the plane-wave ultrasoft pseudopotential method. The defect formation energy, band structure, density of states, mulliken charges, and optical spectra were calculated and discussed in detail. The results demonstrated that in Zn0.875Se and Zn0.875Cu0.125Se systems, because of the introduction of the vacancy acceptor level or acceptor impurity level, the band gap is reduced, and the absorption peaks show a remarkable redshift. Cu doping into the ZnSe system was found to be relatively stable, while the monovacancy system was not.

Key words: ZnSe, Vacancy defect, Cu doping, Electronic structure, Optical property, First-principles