Anharmonicity and local lattice distortion in strained Ge-dilute Si1-xGex alloy

	Anharmonicity and local lattice distortion in strained Ge-dilute Si1-xGex alloy
	Dong JC(董俊才); Guo ZY(郭志英); Zhang XL(张晓丽); An PF(安鹏飞); Gong Y(宫宇); Zhu HL(朱海亮); Li PS(李鹏善); Chen DL(陈栋梁); Dong; Juncai
刊名	JOURNAL OF ALLOYS AND COMPOUNDS
	2015
卷号	653 页码:117-121
关键词	Anharmonicity Local lattice distortion Substrate effect Strain relaxation mechanism Si1-xGex alloy
通讯作者	陈栋梁
英文摘要	We have investigated the anharmonicity and local lattice distortion in strained Ge-dilute Si1-xGex alloy using Ge K-edge extended x-ray absorption fine structure measurement coupled with ab initio molecular dynamics simulation. Pronounced asymmetry is for the first time revealed for the Ge-Si first nearestneighbor (NN) distribution even at room temperature, in good agreement with theoretical simulations. In comparison with harmonic approximation, the anharmonicity contributes an additional shift of 0.011 angstrom to the Ge-Si first NN bond distance, which is further found to be crucial to the qualitative change (i.e., contracting or stretching) of the Ge-Si second NN bond distance relative to the corresponding Si-Si bond distance in bulk Si. As the modifications of higher NN shells arise from the competition between the NN bond-distance stretching and the tetrahedral bond-angle deviation, those results indicate that the anharmonicity is critical in the proper determination of the local strain accommodation mode and thus the substrate effect. Farther NN shells exhibit slight asymmetry. Our findings reconcile the long-standing controversy regarding the dominant local strain relaxation mechanism in strained Ge-dilute Si1-xGex alloys. (C) 2015 Elsevier B.V. All rights reserved.
学科主题	Chemistry; Materials Science; Metallurgy & Metallurgical Engineering
类目[WOS]	Chemistry, Physical ; Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering
收录类别	SCI ; EI ; CA
WOS记录号	WOS:000363270000016
公开日期	2016-05-03
内容类型	期刊论文
源URL	[http://ir.ihep.ac.cn/handle/311005/228900]
专题	高能物理研究所_多学科研究中心
推荐引用方式 GB/T 7714	Dong JC,Guo ZY,Zhang XL,et al. Anharmonicity and local lattice distortion in strained Ge-dilute Si1-xGex alloy[J]. JOURNAL OF ALLOYS AND COMPOUNDS,2015,653:117-121.
APA	董俊才.,郭志英.,张晓丽.,安鹏飞.,宫宇.,...&Dongliang.(2015).Anharmonicity and local lattice distortion in strained Ge-dilute Si1-xGex alloy.JOURNAL OF ALLOYS AND COMPOUNDS,653,117-121.
MLA	董俊才,et al."Anharmonicity and local lattice distortion in strained Ge-dilute Si1-xGex alloy".JOURNAL OF ALLOYS AND COMPOUNDS 653(2015):117-121.