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arXiv · 1808.10713

Phonon transport across a Si-Ge interface: the role of inelastic bulk scattering

Jesse Maassen·Vahid Askarpour
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Abstract

Understanding phonon transport across heterojunctions is important to achieve a wide range of thermal transport properties. Using the McKelvey-Shockley flux method with first-principles modeling, we theoretically investigate the phonon transport properties of a Si-Ge interface with a focus on the role of inelastic bulk phonon processes. We observe significant inelastic scattering near the interface that redistributes the heat among the phonons as a result of non-equilibrium effects driven by the junction. These effects are most pronounced when the length of the junction is comparable to the average phonon mean-free-path. What controls these inelastic processes is elucidated.

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Jesse Maassen, Vahid Askarpour. 2018-08-31. Phonon transport across a Si-Ge interface: the role of inelastic bulk scattering. https://arxiv.org/abs/1808.10713

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