| Deformation-induced blueshift in emission spectrum of CdTe quantum dot composites |
| Xiao P(肖攀); Ke FJ(柯孚久); Bai YL(白以龙); Zhou M; Zhou, M (reprint author), Georgia Inst Technol, George W Woodruff Sch Mech Engn, Sch Mat Sci & Engn, Atlanta, GA 30332 USA.
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发表期刊 | COMPOSITES PART B-ENGINEERING
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| 2017-07-01
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卷号 | 120页码:54-62 |
ISSN | 1359-8368
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摘要 | Polymer or glass films impregnated with quantum dots (QDs) have potential applications for mesoscale stress/strain sensing in the interior of materials under mechanical loading. One requirement in the development of such nanocomposite sensor materials is the establishment of calibrated relations between shifts in the emission spectrum of QD systems and the input stress/strain on the composites. Here we use a multiscale computational framework to quantify the strain-dependent blueshift in the emission spectrum of CdTe QDs uniformly distributed in a matrix material under loading of a range of strain triaxiality. The framework which combines the finite element method molecular dynamics simulations and the empirical tight-binding method captures the QD/matrix interactions possible deformation induced phase transformations and strain-dependent band structures of the QDs. Calculations reveal that the response of the QDs is strongly dependent on state of input strain. Under hydrostatic compression the blueshift increases monotonically with strain. Under compression with lateral/axial strain ratios between 0.0 and 0.5 the blueshift initially increases reaches a peak at an intermediate strain and subsequently decreases with strain. This trend reflects a competition between increases in the energy levels associated with the conduction and valence bands of the QDs. The deformation-induced blueshift is also found to be dependent on QD orientations. The averaged blueshift over all orientations for the composite under uniaxial strain condition explains the blueshift variation trend observed in laser-driven shock compression experiments. Based on the simulation result guidelines for developing QD composites as stress/strain sensing materials are discussed. (C) 2017 Elsevier Ltd. All rights reserved. |
关键词 | Cdte Quantum Dot
Band Gap
Empirical Tight Binding
Molecular Dynamics
Finite Element Method
Pressure Sensor
Laser-driven Shock Compression
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DOI | 10.1016/j.compositesb.2017.03.067
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收录类别 | SCI
; EI
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语种 | 英语
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WOS记录号 | WOS:000402496700006
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关键词[WOS] | ELECTRONIC-STRUCTURE
; TIGHT-BINDING
; HIGH-PRESSURE
; SEMICONDUCTORS
; TRANSITIONS
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WOS研究方向 | Engineering
; Materials Science
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WOS类目 | Engineering, Multidisciplinary
; Materials Science, Composites
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项目资助者 | Defense Threat Reduction Agency (DTRA)(HDTRA1-12-1-0052)
; Strategic Priority Research Program (B) of the Chinese Academy of Sciences(XDB22040501)
; National Natural Science Foundation of China(11202212
; 11432014
; 11672298)
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课题组名称 | LNM材料的分子/细观统计力学行为
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论文分区 | 一类
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力学所作者排名 | 1
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引用统计 |
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文献类型 | 期刊论文
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条目标识符 | http://dspace.imech.ac.cn/handle/311007/60517
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专题 | 非线性力学国家重点实验室
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通讯作者 | Zhou, M (reprint author), Georgia Inst Technol, George W Woodruff Sch Mech Engn, Sch Mat Sci & Engn, Atlanta, GA 30332 USA. |
推荐引用方式 GB/T 7714 |
Xiao P,Ke FJ,Bai YL,et al. Deformation-induced blueshift in emission spectrum of CdTe quantum dot composites[J]. COMPOSITES PART B-ENGINEERING,2017,120:54-62.
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APA |
肖攀,柯孚久,白以龙,Zhou M,&Zhou, M .(2017).Deformation-induced blueshift in emission spectrum of CdTe quantum dot composites.COMPOSITES PART B-ENGINEERING,120,54-62.
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MLA |
肖攀,et al."Deformation-induced blueshift in emission spectrum of CdTe quantum dot composites".COMPOSITES PART B-ENGINEERING 120(2017):54-62.
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