An <i>ab initio</i> study of multiple phonon scattering resonances in silicon germanium alloys

Mendoza, Jonathan; Esfarjani, Keivan; Chen, Gang

doi:10.1063/1.4919661

Cited by 10 publications

(12 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is questionable when the wavelength of phonons is comparable to the characteristic length of the disorder. It has been shown by using a full-order scattering theory that, the VCA fails for high frequency phonons and predicts incorrect phonon density of state [57]. However, such high frequency phonons are shown to have large scattering rates [57], which make VCA still a good approximation in evaluating the heat transport of alloys.…”

Section: Impurity Scatteringmentioning

confidence: 99%

First-principles calculations of thermal, electrical, and thermoelectric transport properties of semiconductors

Zhou

Liao

Chen

2016

Semicond. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

Transport properties of semiconductors are keys to the performance of many solid-state devices (transistors, data storage, thermoelectric cooling and power generation devices, etc.).Understanding of the transport details can lead to material designs with better performances. In recent years simulation tools based on first-principles calculations have been greatly improved, being able to obtain the fundamental ground state properties of materials (such as band structure and phonon dispersion) accurately. Accordingly, methods have been developed to calculate the transport properties based on an ab initio approach. In this review we focus on the thermal, electrical, and thermoelectric transport properties of semiconductors, which represent the basic transport characteristics of the two degrees of freedom in solids -electronic and lattice degrees of freedom.Starting from the coupled electron-phonon Boltzmann transport equations, we illustrate different scattering mechanisms that change the transport features and review the first-principles approaches that solve the transport equations. We then present the first-principles results on the thermal and electrical transport properties of semiconductors. The discussions are grouped based on different scattering mechanisms including phonon-phonon scattering, phonon scattering by equilibrium electrons, carrier scattering by equilibrium phonons, carrier scattering by polar optical phonons, scatterings due to impurities, alloying and doping, and phonon drag effect. We show how the first-principles methods allow one to investigate the transport properties with unprecedented details and also offer new insights to the electron and phonon transport. Current status of the simulation is mentioned when appropriate and some of the future directions are also discussed.

show abstract

Section: Impurity Scatteringmentioning

confidence: 99%

First-principles calculations of thermal, electrical, and thermoelectric transport properties of semiconductors

Zhou

Liao

Chen

2016

Semicond. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is expected that these modes do not significantly contribute to thermal conductivity, as their group velocities are small and their lifetimes have been reduced by mass disorder scattering. The virtual crystal approximation is expected to break down when the mass disorder takes on a correlation length on the order of the probing length scale [23].…”

Section: Theory a First Principle Calculationsmentioning

confidence: 99%

Unifying first-principles theoretical predictions and experimental measurements of size effects in thermal transport in SiGe alloys

Huberman

Chiloyan

Duncan

et al. 2017

Phys. Rev. Materials

Self Cite

View full text Add to dashboard Cite

In this work, we demonstrate the correspondence between first principle calculations and experimental measurements of size effects on thermal transport in SiGe alloys. Transient thermal grating (TTG) is used to measure the effective thermal conductivity. The virtual crystal approximation under the density functional theory (DFT) framework combined with impurity scattering is used to determine the phonon properties for the exact alloy composition of the measured samples. With these properties, classical size effects are calculated for the experimental geometry of reflection mode TTG using the recently-developed variational solution to the phonon Boltzmann transport equation (BTE), which is verified against established Monte Carlo simulations. We find agreement between theoretical predictions and experimental measurements in the reduction of thermal conductivity (as much as ∼ 25% of the bulk value) across grating periods spanning one order of magnitude. This work provides a framework for the tabletop study of size effects on thermal transport. * gchen2@mit.edu 1 arXiv:1704.01386v2 [cond-mat.mes-hall]

show abstract

“…"# and ξ is the strong departure from Rayleigh behavior at 1.5 THz when both values suddenly drop two orders of magnitude. Since 1.5 THz corresponds to the fifth band edge in the zone-folded Brillouin zone representation, the low group velocities leads to resonant scattering [8,31,32]. Beyond 1.5 THz, !…”

mentioning

confidence: 99%

Anderson Localization of Thermal Phonons Leads to a Thermal Conductivity Maximum

Mendoza

Chen

2016

Nano Lett.

Self Cite

View full text Add to dashboard Cite

Our elastic model of ErAs disordered GaAs/AlAs superlattices exhibits a local thermal conductivity maximum as a function of length due to exponentially suppressed Anderson-localized phonons. By analyzing the sample-to-sample fluctuations in the dimensionless conductance, !, the transition from diffusive to localized transport is identified as the crossover from the multi-channel to single-channel transport regime ! ≈ 1. Single parameter scaling is shown to hold in this crossover regime through the universality of the probability distribution of ! that is independent of system size and disorder strength.

show abstract

An ab initio study of multiple phonon scattering resonances in silicon germanium alloys

Cited by 10 publications

References 29 publications

First-principles calculations of thermal, electrical, and thermoelectric transport properties of semiconductors

First-principles calculations of thermal, electrical, and thermoelectric transport properties of semiconductors

Unifying first-principles theoretical predictions and experimental measurements of size effects in thermal transport in SiGe alloys

Anderson Localization of Thermal Phonons Leads to a Thermal Conductivity Maximum

Contact Info

Product

Resources

About