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Heat vortex in hydrodynamic phonon transport of two-dimensional materials.

ABSTRACT: We study hydrodynamic phonon heat transport in two-dimensional (2D) materials. Starting from the Peierls-Boltzmann equation with the Callaway model approximation, we derive a 2D Guyer-Krumhansl-like equation describing hydrodynamic phonon transport, taking into account the quadratic dispersion of flexural phonons. In addition to Poiseuille flow, second sound propagation, the equation predicts heat current vortices and negative non-local thermal conductance in 2D materials, which are common in classical fluids but have not yet been considered in phonon transport. Our results also illustrate the universal transport behaviors of hydrodynamics, independent of the type of quasi-particles and their microscopic interactions.

SUBMITTER: Shang MY

PROVIDER: S-EPMC7237709 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Heat vortex in hydrodynamic phonon transport of two-dimensional materials.

Shang Man-Yu MY Zhang Chuang C Guo Zhaoli Z Lü Jing-Tao JT

Scientific reports 20200519 1

We study hydrodynamic phonon heat transport in two-dimensional (2D) materials. Starting from the Peierls-Boltzmann equation with the Callaway model approximation, we derive a 2D Guyer-Krumhansl-like equation describing hydrodynamic phonon transport, taking into account the quadratic dispersion of flexural phonons. In addition to Poiseuille flow, second sound propagation, the equation predicts heat current vortices and negative non-local thermal conductance in 2D materials, which are common in cl ...[more]

PMID: 32427969

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