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arXiv · 1609.08133

Anisotropic heat conduction in silicon nanowire network revealed by Raman scattering

Mykola Isaiev·Oles Didukh·Tetyana Nychyporuk·Victor Timoshenko·Vladimir Lysenko
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Abstract

Anisotropic nanomaterials possess interesting thermal transport properties because they allow orientation of heat fluxes along preferential directions due to a high ratio (up to three orders of magnitude) between their in-plane and cross-plane thermal conductivities. Among different techniques allowing thermal conductivity evaluation, micro-Raman scattering is known to be one of the most efficient contactless measurement approaches. In this letter, a new experimental approach based on Raman scattering measurements with variable laser spot sizes is reported. Correlation between experimental and calculated thermal resistances of one-dimensional nanocrystalline solids allows simultaneous estimation of their in-plane and cross-plane thermal conductivities. In particular, our measurement approach is illustrated to be successfully applied for anisotropic thermal conductivity evaluation of silicon nanowire arrays.

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Mykola Isaiev, Oles Didukh, Tetyana Nychyporuk, Victor Timoshenko, Vladimir Lysenko. 2016-09-26. Anisotropic heat conduction in silicon nanowire network revealed by Raman scattering. https://doi.org/10.1063/1.4973737

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