Interface bond relaxation on the thermal conductivity of Si/Ge core-shell nanowires

Chen, Weifeng; He, Yan; Ouyang, Gang; Sun, Changqing

doi:10.1063/1.4940768

Title: Interface bond relaxation on the thermal conductivity of Si/Ge core-shell nanowires

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Abstract

The thermal conductivity of Si/Ge core-shell nanowires (CSNWs) is investigated on the basis of atomic-bond-relaxation consideration and continuum mechanics. An analytical model is developed to clarify the interface bond relaxation of Si/Ge CSNWs. It is found that the thermal conductivity of Si core can be modulated through covering with Ge epitaxial layers. The change of thermal conductivity in Si/Ge CSNWs should be attributed to the surface relaxation and interface mismatch between inner Si nanowire and outer Ge epitaxial layer. Our results are in well agreement with the experimental measurements and simulations, suggesting that the presented method provides a fundamental insight of the thermal conductivity of CSNWs from the atomistic origin.

Authors:

Chen, Weifeng; He, Yan; Ouyang, Gang ^[1]; Sun, Changqing ^[2]

Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Synergetic Innovation Center for Quantum Effects and Applications(SICQEA), Hunan Normal University, Changsha 410081 (China)
School of Electrical & Electronic Engineering, Nanyang Technological University, Singapore 639798 (Singapore)

Publication Date:: Fri Jan 15 00:00:00 EST 2016

OSTI Identifier:: 22492419

Resource Type:: Journal Article

Journal Name:: AIP Advances

Additional Journal Information:: Journal Volume: 6; Journal Issue: 1; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 2158-3226

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; EPITAXY; GERMANIUM; INTERFACES; LAYERS; NANOWIRES; RELAXATION; SILICON; SURFACES; THERMAL CONDUCTIVITY

Citation Formats


                    Chen, Weifeng, He, Yan, Ouyang, Gang, and Sun, Changqing. Interface bond relaxation on the thermal conductivity of Si/Ge core-shell nanowires.  United States: N. p., 2016. 
        Web.  doi:10.1063/1.4940768.

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                    Chen, Weifeng, He, Yan, Ouyang, Gang, & Sun, Changqing. Interface bond relaxation on the thermal conductivity of Si/Ge core-shell nanowires.  United States.  https://doi.org/10.1063/1.4940768

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                    Chen, Weifeng, He, Yan, Ouyang, Gang, and Sun, Changqing. 2016.  
        "Interface bond relaxation on the thermal conductivity of Si/Ge core-shell nanowires".  United States.  https://doi.org/10.1063/1.4940768.

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@article{osti_22492419,

  title        = {Interface bond relaxation on the thermal conductivity of Si/Ge core-shell nanowires},

  author       = {Chen, Weifeng and He, Yan and Ouyang, Gang and Sun, Changqing},

  abstractNote = {The thermal conductivity of Si/Ge core-shell nanowires (CSNWs) is investigated on the basis of atomic-bond-relaxation consideration and continuum mechanics. An analytical model is developed to clarify the interface bond relaxation of Si/Ge CSNWs. It is found that the thermal conductivity of Si core can be modulated through covering with Ge epitaxial layers. The change of thermal conductivity in Si/Ge CSNWs should be attributed to the surface relaxation and interface mismatch between inner Si nanowire and outer Ge epitaxial layer. Our results are in well agreement with the experimental measurements and simulations, suggesting that the presented method provides a fundamental insight of the thermal conductivity of CSNWs from the atomistic origin.},

  doi          = {10.1063/1.4940768},

  url          = {https://www.osti.gov/biblio/22492419},
  journal      = {AIP Advances},

  issn         = {2158-3226},

  number       = 1,

  volume       = 6,

  place        = {United States},

  year         = {Fri Jan 15 00:00:00 EST 2016},

  month        = {Fri Jan 15 00:00:00 EST 2016}

}

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