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Gang Chen. Henry, Asegun Sekou Famake Massachusetts Institute of Technology. Dept. of Mechanical Engineering. Massachusetts Institute of Technology. Department of Mechanical Engineering 2007-02-21T13:11:06Z 2007-02-21T13:11:06Z 2006 2006 http://hdl.handle.net/1721.1/36233 77063769 Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006. Includes bibliographical references (p. 91-95). Due to the technological significance of silicon, its heat conduction mechanisms have been studied extensively. However, there have been some lingering questions surrounding the phonon mean free path and importance of different polarizations. This research investigates phonon transport in bulk crystalline silicon using molecular dynamics and lattice dynamics. The interactions are modeled with the environment dependent interatomic potential (EDIP), which was designed to represent the bulk phases of silicon. Temperature and phonon frequency dependent relaxation times are extracted from the MD simulations and used to generate a detailed picture of phonon transport. It is found that longitudinal acoustic phonons have the highest contribution to thermal conductivity and that the phonon mean free path varies by orders of magnitude with respect to the phonon spectra. For relaxation times, we observe moderate anisotropy and good agreement with the frequency dependence predicted by scattering theories. We also find that phonons with mean free paths between .1 and 10 micron are responsible for 50% of the thermal conduction, while phonons with wavelengths less than 10 nanometers make up 80%. by Asegun Sekou Famake Henry. S.M. 95 p. eng Massachusetts Institute of Technology M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 Mechanical Engineering. Molecular dynamics analysis of spectral characteristics of phonon heat conduction in silicon Thesis application/pdf false Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="baf08613-2a9c-4f00-8063-9ed6512d26cc"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Molecular dynamics analysis of spectral characteristics of phonon heat conduction in silicon</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2006</PublicationDate> <Authors> <Author> <DisplayName>Henry, Asegun Sekou Famake</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Mechanical Engineering.</Keyword> <Abstract>Due to the technological significance of silicon, its heat conduction mechanisms have been studied extensively. However, there have been some lingering questions surrounding the phonon mean free path and importance of different polarizations. This research investigates phonon transport in bulk crystalline silicon using molecular dynamics and lattice dynamics. The interactions are modeled with the environment dependent interatomic potential (EDIP), which was designed to represent the bulk phases of silicon. Temperature and phonon frequency dependent relaxation times are extracted from the MD simulations and used to generate a detailed picture of phonon transport. It is found that longitudinal acoustic phonons have the highest contribution to thermal conductivity and that the phonon mean free path varies by orders of magnitude with respect to the phonon spectra. For relaxation times, we observe moderate anisotropy and good agreement with the frequency dependence predicted by scattering theories. We also find that phonons with mean free paths between .1 and 10 micron are responsible for 50% of the thermal conduction, while phonons with wavelengths less than 10 nanometers make up 80%.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>