Disentangling phonon channels in nanoscale heat transport

Phonon surface scattering has been at the core of heat transport engineering in nanoscale devices. Herein, we demonstrate that this phonon pathway can be the sole mechanism only below a critical, size-dependent temperature. Above this temperature, the lattice phonon scattering coexists along with su...

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Detalles Bibliográficos
Autores: Mukherjee, Samik|||0000-0002-5279-1110, Wajs, Marcin, De La Mata, Maria|||0000-0002-1581-4838, Givan, Uri, Senz, Stephan, Arbiol i Cobos, Jordi|||0000-0002-0695-1726, Francoeur, Sebastien|||0000-0002-6129-7026, Moutanabbir, Oussama|||0000-0002-0721-3696
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:271935
Acceso en línea:https://ddd.uab.cat/record/271935
https://dx.doi.org/urn:doi:10.1103/PhysRevB.104.075429
Access Level:acceso abierto
Palabra clave:Chemical compositions
Critical temperatures
Design and modeling
Equilibrium transport
Nano-scale system
Nanoscale device
Nanoscale heat transports
Phonon-scattering mechanisms
Descripción
Sumario:Phonon surface scattering has been at the core of heat transport engineering in nanoscale devices. Herein, we demonstrate that this phonon pathway can be the sole mechanism only below a critical, size-dependent temperature. Above this temperature, the lattice phonon scattering coexists along with surface effects. By tailoring the mass disorder at the atomic level, the lattice dynamics in nanowires was artificially controlled without affecting morphology, crystallinity, chemical composition, or electronic properties, thus allowing the mapping of the temperature-thermal conductivity-diameter triple parameter space. This led to the identification of the critical temperature below which the effects of lattice mass disorder are suppressed to an extent that phonon transport becomes governed entirely by the surface. This behavior is discussed based on a modified Landauer-Datta-Lundstrom near-equilibrium transport model. Besides disentangling the main phonon scattering mechanisms, the established framework also provides the necessary input to further advance the design and modeling of heat transport in semiconductor nanoscale systems.