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Nernst effect in semi-metals: the meritorious heaviness of electrons

Kamran Behnia·Marie-Aude Measson·Yakov Kopelevich
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Abstract

We present a study of electric, thermal and thermoelectric transport in elemental Bismuth, which presents a Nernst coefficient much larger than what was found in correlated metals. We argue that this is due to the combination of an exceptionally low carrier density with a very long electronic mean-free-path. The low thermomagnetic figure of merit is traced to the lightness of electrons. Heavy-electron semi-metals, which keep a metallic behavior in presence of a magnetic field, emerge as promising candidates for thermomagnetic cooling at low temperatures.

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Kamran Behnia, Marie-Aude Measson, Yakov Kopelevich. 2007-02-21. Nernst effect in semi-metals: the meritorious heaviness of electrons. https://doi.org/10.1103/physrevlett.98.076603

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