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arXiv · 1703.04996

Exceptionally strong phonon scattering by B substitution in cubic SiC

Ankita Katre·Jesús Carrete·Bonny Dongre·Georg K. H. Madsen·Natalio Mingo
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Abstract

We use ab-initio calculations to predict the thermal conductivity of cubic SiC with different types of defects. An excellent quantitative agreement with previous experimental measurements is found. The results unveil that B$_\mathrm{C}$ substitution has a much stronger effect than any of the other defect types in 3C-SiC, including vacancies. This finding contradicts the prediction of the classical mass-difference model of impurity scattering, according to which the effects of B$_\mathrm{C}$ and N$_\mathrm{C}$ would be similar and much smaller than that of the C vacancy. The strikingly different behavior of the B$_\mathrm{C}$ defect arises from a unique pattern of resonant phonon scattering caused by the broken structural symmetry around the B impurity.

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Ankita Katre, Jesús Carrete, Bonny Dongre, Georg K. H. Madsen, Natalio Mingo. 2017-03-15. Exceptionally strong phonon scattering by B substitution in cubic SiC. https://doi.org/10.1103/physrevlett.119.075902

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