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arXiv · 1801.04330

Hydrodynamic heat transport regime in bismuth: a theoretical viewpoint

Maxime Markov·Jelena Sjakste·Giuliana Barbarino·Giorgia Fugallo·Lorenzo Paulatto·Michele Lazzeri·Francesco Mauri·Nathalie Vast
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Abstract

Bismuth is one of the rare materials in which second sound has been experimentally observed. Our exact calculations of thermal transport with the Boltzmann equation predict the occurrence of this Poiseuille phonon flow between $\approx$ 1.5 K and $\approx$ 3.5 K, in sample size of 3.86 mm and 9.06 mm, in consistency with the experimental observations. Hydrodynamic heat flow characteristics are given for any temperature: heat wave propagation length, drift velocity, Knudsen number. We discuss a Gedanken-experiment allowing to assess the presence of a hydrodynamic regime in any bulk material.

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Maxime Markov, Jelena Sjakste, Giuliana Barbarino, Giorgia Fugallo, Lorenzo Paulatto, Michele Lazzeri, Francesco Mauri, Nathalie Vast. 2018-01-12. Hydrodynamic heat transport regime in bismuth: a theoretical viewpoint. https://doi.org/10.1103/physrevlett.120.075901

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