Role of light and heavy embedded nanoparticles on the thermal conductivity of SiGe alloys
- 9 September 2011
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review B
- Vol. 84 (12), 125426
- https://doi.org/10.1103/physrevb.84.125426
Abstract
We have used an atomistic ab initio approach with no adjustable parameters to compute the lattice thermal conductivity of SiGe with a low concentration of embedded Si or Ge nanoparticles of diameters up to 4.4 nm. Through exact Green’s function calculation of the nanoparticle scattering rates, we find that embedding Ge nanoparticles in provides 20% lower thermal conductivities than embedding Si nanoparticles. This contrasts with the Born approximation, which predicts an equal amount of reduction for the two cases, irrespective of the sign of the mass difference. Despite these differences, we find that the Born approximation still performs remarkably well, and it permits investigation of larger nanoparticle sizes, up to 60 nm in diameter, not feasible with the exact approach.
Keywords
This publication has 23 references indexed in Scilit:
- Low-Temperature Thermoelectric Power Factor Enhancement by Controlling Nanoparticle Size DistributionNano Letters, 2010
- Diameter dependence of carbon nanotube thermal conductivity and extension to the graphene limitPhysical Review B, 2010
- Ab initiotheory of the lattice thermal conductivity in diamondPhysical Review B, 2009
- “Nanoparticle-in-Alloy” Approach to Efficient Thermoelectrics: Silicides in SiGeNano Letters, 2009
- Intrinsic lattice thermal conductivity of semiconductors from first principlesApplied Physics Letters, 2007
- Phonon scattering cross section of polydispersed spherical nanoparticlesJournal of Applied Physics, 2006
- Thermal Conductivity Reduction and Thermoelectric Figure of Merit Increase by Embedding Nanoparticles in Crystalline SemiconductorsPhysical Review Letters, 2006
- Cubic AgPb
m
SbTe 2+
m
: Bulk Thermoelectric Materials with High Figure of MeritScience, 2004
- The maximum possible conversion efficiency of silicon-germanium thermoelectric generatorsJournal of Applied Physics, 1991
- Phonon scattering by impurity platelet precipitates in diamondPhysical Review B, 1974