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Towards the grain boundary phonon scattering problem: an evidence for a low-temperature crossover

V. A. Osipov·S. E. Krasavin
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Abstract

The problem of phonon scattering by grain boundaries is studied within the wedge disclination dipole (WDD) model. It is shown that a specific q-dependence of the phonon mean free path for biaxial WDD results in a low-temperature crossover of the thermal conductivity, $κ$. The obtained results allow to explain the experimentally observed deviation of $κ$ from a $T^3$ dependence below $0.1K$ in $LiF$ and $NaCl$.

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V. A. Osipov, S. E. Krasavin. 1998-07-14. Towards the grain boundary phonon scattering problem: an evidence for a low-temperature crossover. https://doi.org/10.1088/0953-8984%2F10%2F36%2F002

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