Thermal conductivity and phonon transport properties of silicon using perturbation theory and the environment-dependent interatomic potential

Perturbation theory is used to compute the strength of three-phonon and isotope scattering mechanisms in silicon using the Environment-Dependent Interatomic Potential (EDIP) without resorting to any parameter-fitting. A detailed methodology to accurately find three-phonon processes satisfying energy- and momentum-conservation rules is described. Bulk silicon thermal conductivity values are computed across a range of temperatures and shown to match experimental data well. It is found that about two-thirds of the heat transport in bulk silicon may be attributed to transverse acoustic modes. Effective relaxation times and mean free paths are computed in order to provide a more complete picture of the detailed transport mechanisms and for use with carrier transport models based on the Boltzmann transport equation.

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Designing Si/Si1−xGex Superlattices With Tailored Thermal Transport Properties

Heat Transfer: Volume 1 ◽

10.1115/ht2008-56473 ◽

2008 ◽

Author(s):

E. S. Landry ◽

A. J. H. McGaughey

Keyword(s):

Thermal Conductivity ◽

Experimental Study ◽

Transport Properties ◽

Electrical Transport ◽

Design Space ◽

Phonon Transport ◽

Atomistic Modeling ◽

Electrical Transport Properties ◽

Modeling Tools ◽

Thermoelectric Energy

Si/Si1−xGex superlattices are promising candidates for thermoelectric energy conversion applications [1, 2], as the phonon transport through them can be inhibited while maintaining desirable electrical transport properties. No comprehensive experimental study has been performed to map the thermal conductivity design space accessible by Si/Ge nanocomposites. By using atomistic modeling tools, interesting areas of the design space can be identified and then further explored experimentally.

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Spectral Detail of Phonon Conduction and Scattering in Graphene

ASME 2011 Pacific Rim Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Systems, MEMS and NEMS: Volume 1 ◽

10.1115/ipack2011-52243 ◽

2011 ◽

Author(s):

Dhruv Singh ◽

Jayathi Y. Murthy ◽

Timothy S. Fisher

Keyword(s):

Thermal Conductivity ◽

Phonon Scattering ◽

Interatomic Potential ◽

Phonon Dispersion ◽

Transition Probabilities ◽

Transition Probability ◽

Phonon Transport ◽

Temperature Perturbation ◽

Boltzmann Transport ◽

Wide Range

This paper examines the thermodynamic and thermal transport properties of the 2D graphene lattice. The interatomic interactions are modeled using the Tersoff interatomic potential and are used to evaluate phonon dispersion curves, density of states and thermodynamic properties of graphene as functions of temperature. Perturbation theory is applied to calculate the transition probabilities for three-phonon scattering. The matrix elements of the perturbing Hamiltonian are calculated using the anharmonic interatomic force constants obtained from the interatomic potential as well. An algorithm to accurately quantify the contours of energy balance for three-phonon scattering events is presented and applied to calculate the net transition probability from a given phonon mode. Under the linear approximation, the Boltzmann transport equation (BTE) is applied to compute the thermal conductivity of graphene, giving spectral and polarization-resolved information. Predictions of thermal conductivity for a wide range of parameters elucidate the behavior of diffusive phonon transport. The complete spectral detail of selection rules, important phonon scattering pathways, and phonon relaxation times in graphene are provided, contrasting graphene with other materials, along with implications for graphene electronics. We also highlight the specific scattering processes that are important in Raman spectroscopy based measurements of graphene thermal conductivity, and provide a plausible explanation for the observed dependence on laser spot size.

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Two-dimensional bucking structure induces the ultra-low thermal conductivity: A comparative study of the group GaX (X = N, P, As)

Journal of Materials Chemistry C ◽

10.1039/d1tc04531h ◽

2022 ◽

Author(s):

Chen Shen ◽

Niloofar Hadaeghi ◽

Harish K. Singh ◽

Teng Long ◽

Ling Fan ◽

...

Keyword(s):

Thermal Conductivity ◽

Gallium Nitride ◽

Comparative Study ◽

Transport Properties ◽

Honeycomb Structure ◽

Phonon Transport ◽

Two Dimensional ◽

Low Thermal Conductivity

With the successful synthesis of the two-dimensional (2D) gallium nitride (GaN) in a planar honeycomb structure, the phonon transport properties of 2D GaN have been reported. However, it still remains...

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Silicon Thin-Film Lattice Dynamics and Thermal Transport Properties

Volume 7: Fluids and Heat Transfer, Parts A, B, C, and D ◽

10.1115/imece2012-89902 ◽

2012 ◽

Author(s):

Bruce L. Davis ◽

Mehmet Su ◽

Ihab El-Kady ◽

Mahmoud I. Hussein

Keyword(s):

Thin Film ◽

Thin Films ◽

Thermal Conductivity ◽

Transport Properties ◽

Lattice Dynamics ◽

Dielectric Materials ◽

Phonon Transport ◽

Solid State Physics ◽

Silicon Thin Film ◽

Silicon Thin Films

Thin films composed of dielectric materials are attracting growing interest in the solid state physics and nanoscale heat transfer communities. This is primarily due to their unique thermal and electronic properties and their extensive use as components in optoelectronic, and potentially in thermoelectric, devices. In this paper, an elaborate study is presented on silicon thin films ranging from a few nanometers in thickness to very thick bulk-like thicknesses. Full lattice dynamics calculations are performed incorporating the entire film cross section and the relaxation of the free surfaces. The phonon properties emerging from these calculations are then incorporated into Holland-Callaway models to predict the thermal conductivity and other phonon transport properties. A rigorous curve fitting process to a limited set of available experimental data is carried out to obtain the scattering lifetimes. Our results demonstrate the importance of proper consideration of the full thin-film dispersion description and provide insights into the relationship between thermal conductivity, film thickness and temperature.

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High-temperature phonon transport properties of SnSe from machine-learning interatomic potential

Journal of Physics Condensed Matter ◽

10.1088/1361-648x/ac13fd ◽

2021 ◽

Author(s):

Huan Liu ◽

Xin Qian ◽

Hua Bao ◽

Changying Zhao ◽

Xiaokun Gu

Keyword(s):

Machine Learning ◽

High Temperature ◽

Transport Properties ◽

Interatomic Potential ◽

Phonon Transport

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Interatomic potential for predicting the thermal conductivity of zirconium trisulfide monolayers with molecular dynamics

Journal of Applied Physics ◽

10.1063/5.0046823 ◽

2021 ◽

Vol 129 (15) ◽

pp. 155105

Author(s):

Fernan Saiz ◽

Yenal Karaaslan ◽

Riccardo Rurali ◽

Cem Sevik

Keyword(s):

Thermal Conductivity ◽

Molecular Dynamics ◽

Interatomic Potential

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Decoupling electron and phonon transport in single-nanowire hybrid materials for high-performance thermoelectrics

Science Advances ◽

10.1126/sciadv.abe6000 ◽

2021 ◽

Vol 7 (20) ◽

pp. eabe6000

Author(s):

Lin Yang ◽

Madeleine P. Gordon ◽

Akanksha K. Menon ◽

Alexandra Bruefach ◽

Kyle Haas ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermal Transport ◽

Electrical Transport ◽

High Performance ◽

Figure Of Merit ◽

Phonon Transport ◽

Core Shell ◽

Nanowire Diameter ◽

High Performing ◽

Polycrystalline Thin Films

Organic-inorganic hybrids have recently emerged as a class of high-performing thermoelectric materials that are lightweight and mechanically flexible. However, the fundamental electrical and thermal transport in these materials has remained elusive due to the heterogeneity of bulk, polycrystalline, thin films reported thus far. Here, we systematically investigate a model hybrid comprising a single core/shell nanowire of Te-PEDOT:PSS. We show that as the nanowire diameter is reduced, the electrical conductivity increases and the thermal conductivity decreases, while the Seebeck coefficient remains nearly constant—this collectively results in a figure of merit, ZT, of 0.54 at 400 K. The origin of the decoupling of charge and heat transport lies in the fact that electrical transport occurs through the organic shell, while thermal transport is driven by the inorganic core. This study establishes design principles for high-performing thermoelectrics that leverage the unique interactions occurring at the interfaces of hybrid nanowires.

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