Impact of Surface Passivation on the Electronic Structure and Optical Properties of the Si1-xGex Nanowires  

作　　者：赖信 张析 张依兮 向钢 

机构地区：[1]College of Physical Science and Technology,Sichuan University [2]Key Laboratory of High Energy Density Physics and Technology of Ministry of Education,Sichuan University

出　　处：《Chinese Physics Letters》2015年第2期119-122,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant No 11004142;the Program for New Century Excellent Talents in University under Grant No 11-035;the Project Sponsored by the Scientific Research Foundation for ROCS of the Ministry of Education of China

摘　　要：The electronic structures and optical properties of the [llO]-oriented Sil-xGex nanowires （NWs） passivated with different functional groups （-H, -F and-OH） are investigated by using first-principles calculations. The results show that surface passivation influences the characteristics of electronic band structures significantly： the band gap widths and types （direct or indirect） of the Si1-xGe, NWs with different terminators show complex and robust variations, and the effective masses of the electrons in the NWs can be modulated dramatically by the terminators. The study of optical absorption shows that the main peaks of the parallel polarization component of Si1-x Gex NWs passivated with the functional groups exhibit prominent changes both in height and position, and are red-shifted with respect to those of corresponding pure Si NWs, indicating the importance of both the terminators and Ge concentrations. Our results demonstrate that the electronic and optical properties of Si1-xGex NWs can be tuned by utilizing selected functional groups as well as particular Ge concentrations for customizing purposes.The electronic structures and optical properties of the [llO]-oriented Sil-xGex nanowires （NWs） passivated with different functional groups （-H, -F and-OH） are investigated by using first-principles calculations. The results show that surface passivation influences the characteristics of electronic band structures significantly： the band gap widths and types （direct or indirect） of the Si1-xGe, NWs with different terminators show complex and robust variations, and the effective masses of the electrons in the NWs can be modulated dramatically by the terminators. The study of optical absorption shows that the main peaks of the parallel polarization component of Si1-x Gex NWs passivated with the functional groups exhibit prominent changes both in height and position, and are red-shifted with respect to those of corresponding pure Si NWs, indicating the importance of both the terminators and Ge concentrations. Our results demonstrate that the electronic and optical properties of Si1-xGex NWs can be tuned by utilizing selected functional groups as well as particular Ge concentrations for customizing purposes.

关 键 词：110 OH x)Ge_x Nanowires Impact of Surface Passivation on the Electronic Structure and Optical Properties of the Si Ge 

分 类 号：TB383.1[一般工业技术—材料科学与工程]