Interfacial thermal transport with strong system-bath coupling: A phonon delocalization effect
We study the effect of system-bath coupling strength on quantum thermal transport through the interface of two weakly coupled anharmonic molecular chains by using a quantum self-consistent phonon approach. The approach inherently assumes that the two segments (anharmonic molecular chains) are approx...
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| Other Authors: | |
| Format: | Article |
| Language: | English |
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American Physical Society
2018
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| Online Access: | http://hdl.handle.net/1721.1/115891 https://orcid.org/0000-0001-7616-7809 |
| _version_ | 1826199281293328384 |
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| author | He, Dahai Thingna, Juzar Cao, Jianshu |
| author2 | Massachusetts Institute of Technology. Department of Chemistry |
| author_facet | Massachusetts Institute of Technology. Department of Chemistry He, Dahai Thingna, Juzar Cao, Jianshu |
| author_sort | He, Dahai |
| collection | MIT |
| description | We study the effect of system-bath coupling strength on quantum thermal transport through the interface of two weakly coupled anharmonic molecular chains by using a quantum self-consistent phonon approach. The approach inherently assumes that the two segments (anharmonic molecular chains) are approximately in local thermal equilibrium with respect to the baths that they are connected to and transforms the strongly anharmonic system into an effective harmonic one with a temperature-dependent transmission. Despite the approximations, the approach is ideal for our setup, wherein the weak interfacial coupling guarantees an approximate local thermal equilibrium of each segment and short chain length (less than the phonon mean-free path) ensues from the effective harmonic approximation. Remarkably, the heat current shows a resonant to bi-resonant transition due to the variations in the interfacial coupling and temperature, which is attributed to the delocalization of phonon modes. Delocalization occurs only in the strong system-bath coupling regime and we utilize it to model a thermal rectifier whose ratio can be nonmonotonically tuned not only with the intrinsic system parameters but also with the external temperature. |
| first_indexed | 2024-09-23T11:17:36Z |
| format | Article |
| id | mit-1721.1/115891 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T11:17:36Z |
| publishDate | 2018 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/1158912022-09-27T18:30:45Z Interfacial thermal transport with strong system-bath coupling: A phonon delocalization effect He, Dahai Thingna, Juzar Cao, Jianshu Massachusetts Institute of Technology. Department of Chemistry He, Dahai Cao, Jianshu We study the effect of system-bath coupling strength on quantum thermal transport through the interface of two weakly coupled anharmonic molecular chains by using a quantum self-consistent phonon approach. The approach inherently assumes that the two segments (anharmonic molecular chains) are approximately in local thermal equilibrium with respect to the baths that they are connected to and transforms the strongly anharmonic system into an effective harmonic one with a temperature-dependent transmission. Despite the approximations, the approach is ideal for our setup, wherein the weak interfacial coupling guarantees an approximate local thermal equilibrium of each segment and short chain length (less than the phonon mean-free path) ensues from the effective harmonic approximation. Remarkably, the heat current shows a resonant to bi-resonant transition due to the variations in the interfacial coupling and temperature, which is attributed to the delocalization of phonon modes. Delocalization occurs only in the strong system-bath coupling regime and we utilize it to model a thermal rectifier whose ratio can be nonmonotonically tuned not only with the intrinsic system parameters but also with the external temperature. National Science Foundation (U.S.) (Grant CHE1112825) 2018-05-25T15:11:00Z 2018-05-25T15:11:00Z 2018-05 2018-03 2018-05-23T18:00:21Z Article http://purl.org/eprint/type/JournalArticle 2469-9950 2469-9969 http://hdl.handle.net/1721.1/115891 He, Dahai et al. "Interfacial thermal transport with strong system-bath coupling: A phonon delocalization effect." Physical Review B 97, 19: 195437 © 2018 American Physical Society https://orcid.org/0000-0001-7616-7809 en http://dx.doi.org/10.1103/PhysRevB.97.195437 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. American Physical Society application/pdf American Physical Society American Physical Society |
| spellingShingle | He, Dahai Thingna, Juzar Cao, Jianshu Interfacial thermal transport with strong system-bath coupling: A phonon delocalization effect |
| title | Interfacial thermal transport with strong system-bath coupling: A phonon delocalization effect |
| title_full | Interfacial thermal transport with strong system-bath coupling: A phonon delocalization effect |
| title_fullStr | Interfacial thermal transport with strong system-bath coupling: A phonon delocalization effect |
| title_full_unstemmed | Interfacial thermal transport with strong system-bath coupling: A phonon delocalization effect |
| title_short | Interfacial thermal transport with strong system-bath coupling: A phonon delocalization effect |
| title_sort | interfacial thermal transport with strong system bath coupling a phonon delocalization effect |
| url | http://hdl.handle.net/1721.1/115891 https://orcid.org/0000-0001-7616-7809 |
| work_keys_str_mv | AT hedahai interfacialthermaltransportwithstrongsystembathcouplingaphonondelocalizationeffect AT thingnajuzar interfacialthermaltransportwithstrongsystembathcouplingaphonondelocalizationeffect AT caojianshu interfacialthermaltransportwithstrongsystembathcouplingaphonondelocalizationeffect |