Cluster expansion and optimization of thermal conductivity in SiGe nanowires
We investigate the parametrization and optimization of thermal conductivity in silicon-germanium alloy nanowires by the cluster-expansion technique. Si1−xGex nanowires are of interest for thermoelectric applications and the reduction in lattice thermal conductivity (κL) is desired for enhancing the...
| Main Authors: | , , , , , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
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American Physical Society
2010
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| Online Access: | http://hdl.handle.net/1721.1/58591 |
| _version_ | 1811082122478223360 |
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| author | Chan, Maria K. Reed, J. Donadio, D. Mueller, Timothy K. Meng, Ying Shirley Galli, G. Ceder, Gerbrand |
| author2 | Massachusetts Institute of Technology. Department of Materials Science and Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Materials Science and Engineering Chan, Maria K. Reed, J. Donadio, D. Mueller, Timothy K. Meng, Ying Shirley Galli, G. Ceder, Gerbrand |
| author_sort | Chan, Maria K. |
| collection | MIT |
| description | We investigate the parametrization and optimization of thermal conductivity in silicon-germanium alloy nanowires by the cluster-expansion technique. Si1−xGex nanowires are of interest for thermoelectric applications and the reduction in lattice thermal conductivity (κL) is desired for enhancing the thermoelectric figure of merit. We seek the minimization of κL with respect to arrangements of Si and Ge atoms in 1.5 nm diameter [111] Si1−xGex nanowires, by obtaining κL from equilibrium classical molecular-dynamics (MD) simulations via the Green-Kubo formalism, and parametrizing the results with a coarse-grained cluster expansion. Using genetic algorithm optimization with the coarse-grained cluster expansion, we are able to predict configurations that significantly decrease κL as verified by subsequent MD simulations. Our results indicate that superlatticelike configurations with planes of Ge show drastically lowered κL. |
| first_indexed | 2024-09-23T11:57:55Z |
| format | Article |
| id | mit-1721.1/58591 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T11:57:55Z |
| publishDate | 2010 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/585912022-09-27T23:06:49Z Cluster expansion and optimization of thermal conductivity in SiGe nanowires Chan, Maria K. Reed, J. Donadio, D. Mueller, Timothy K. Meng, Ying Shirley Galli, G. Ceder, Gerbrand Massachusetts Institute of Technology. Department of Materials Science and Engineering Massachusetts Institute of Technology. Department of Physics Ceder, Gerbrand Chan, Maria K. Mueller, Timothy K. Meng, Ying Shirley Ceder, Gerbrand We investigate the parametrization and optimization of thermal conductivity in silicon-germanium alloy nanowires by the cluster-expansion technique. Si1−xGex nanowires are of interest for thermoelectric applications and the reduction in lattice thermal conductivity (κL) is desired for enhancing the thermoelectric figure of merit. We seek the minimization of κL with respect to arrangements of Si and Ge atoms in 1.5 nm diameter [111] Si1−xGex nanowires, by obtaining κL from equilibrium classical molecular-dynamics (MD) simulations via the Green-Kubo formalism, and parametrizing the results with a coarse-grained cluster expansion. Using genetic algorithm optimization with the coarse-grained cluster expansion, we are able to predict configurations that significantly decrease κL as verified by subsequent MD simulations. Our results indicate that superlatticelike configurations with planes of Ge show drastically lowered κL. United States. Defense Advanced Research Projects Agency (W911NF-06-1-0175) United States. Dept. of Energy. SciDAC (DEFC02-06ER25794) 2010-09-17T19:00:08Z 2010-09-17T19:00:08Z 2010-05 2010-03 Article http://purl.org/eprint/type/JournalArticle 1098-0121 1550-235X http://hdl.handle.net/1721.1/58591 Chan, M.K.Y. et al. "Cluster expansion and optimization of thermal conductivity in SiGe nanowires." Physical Review B 81.17 (2010): 174303. © 2010 The American Physical Society en_US http://dx.doi.org/10.1103/PhysRevB.81.174303 Physical Review B Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Physical Society APS |
| spellingShingle | Chan, Maria K. Reed, J. Donadio, D. Mueller, Timothy K. Meng, Ying Shirley Galli, G. Ceder, Gerbrand Cluster expansion and optimization of thermal conductivity in SiGe nanowires |
| title | Cluster expansion and optimization of thermal conductivity in SiGe nanowires |
| title_full | Cluster expansion and optimization of thermal conductivity in SiGe nanowires |
| title_fullStr | Cluster expansion and optimization of thermal conductivity in SiGe nanowires |
| title_full_unstemmed | Cluster expansion and optimization of thermal conductivity in SiGe nanowires |
| title_short | Cluster expansion and optimization of thermal conductivity in SiGe nanowires |
| title_sort | cluster expansion and optimization of thermal conductivity in sige nanowires |
| url | http://hdl.handle.net/1721.1/58591 |
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