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arXiv · 1506.02365

Influence of mass contrast in alloy phonon scattering

Takuma Shiga·Takuma Hori·Junichiro Shiomi
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Abstract

We have investigated the effect of mass contrast on alloy phonon scattering in mass-substituted Lennard-Jones crystals. By calculating the mass-difference phonon scattering rate using a modal analysis method based on molecular dynamics, we have identified the applicability and limits of the widely-used mass-difference perturbation model in terms of magnitude and sign of the mass difference. The result of a phonon -mode-dependent analysis reveals that the critical phonon frequency, above which the mass-difference perturbation theory fails, decreases with the magnitude of the mass difference independently of its sign. This gives rise to a critical mass contrast, above which the mass-difference perturbation model noticeably underestimates the lattice thermal conductivity.

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Takuma Shiga, Takuma Hori, Junichiro Shiomi. 2015-06-08. Influence of mass contrast in alloy phonon scattering. https://doi.org/10.7567/jjap.53.021802

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