Transverse viscous transport in classical solids

Akira Furukawa

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arXiv · 1911.05997

Transverse viscous transport in classical solids

Akira Furukawa

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Abstract

The transverse velocity time correlation function ${\tilde C}_{\rm T}(k,\omega)$ with $k$ and $\omega$ being the wavenumber and the frequency, respectively, is a fundamental quantity in determining the transverse mechanical and transport properties of materials. In ordinary liquids, a nonzero value of ${\tilde C}_{\rm T}(k,0)$ is inevitably associated with viscous material flows. Curiously, even in solids where significant material flows are precluded due to frozen positional degrees of freedom, molecular dynamics simulations reveal that ${\tilde C}_{\rm T}(k,0)$ certainly takes a nonzero value, and in consequence, the time integration of the velocity field shows definite diffusive behavior with diffusivity ${\tilde C}_{\rm T}(k,0)/3$. We demonstrate that this diffusive behavior can be attributed to a solid-specific viscous transport. The resultant viscosity is interpreted as the renormalized viscosity accounting for the nonlinear inertia effect.

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Akira Furukawa. 2019-11-14. Transverse viscous transport in classical solids. https://arxiv.org/abs/1911.05997

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