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Ballistic Thermal Conduction across Acoustically Mismatched Solid Junctions

Jian Wang·Jian-Sheng Wang
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Abstract

We derive expressions for energy flow in terms of lattice normal mode coordinates and energy transmission involving reduced group velocities. With a version of Landauer formula appropriate for lattice dynamic approach, the phonon transmission coefficients and thermal conductance are calculated for two kinds of acoustically mismatched junctions: different chirality nanotubes (11,0) to (8,0), and Si-Ge superlattice structure. Our calculation shows a mode-dependent transmission in nanotube junction and a resonantly modulated ballistic thermal conductance in superlattice. The superlattice result suggests a new interpretation of the experimental data. Our approach provides an atomistic way for the calculation of thermal conduction in nanostructure.

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Jian Wang, Jian-Sheng Wang. 2005-05-17. Ballistic Thermal Conduction across Acoustically Mismatched Solid Junctions. https://arxiv.org/abs/cond-mat/0505401

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