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Oscillating Nernst-Ettingshausen effect in Bismuth across the quantum limit

Kamran Behnia·Marie-Aude Measson·Yakov Kopelevich
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Abstract

In elemental Bismuth, 10$^5$ atoms share a single itinerant electron. Therefore, a moderate magnetic field can confine electrons to the lowest Landau level. We report on the first study of metallic thermoelectricity in this regime. The main thermoelectric response is off-diagonal with an oscillating component several times larger than the non-oscillating background. When the first Landau level attains the Fermi Energy, both the Nernst and the Ettingshausen coefficients sharply peak, and the latter attains a temperature-independent maximum. A qualitative agreement with a theory invoking current-carrying edge excitations is observed.

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Kamran Behnia, Marie-Aude Measson, Yakov Kopelevich. 2007-04-27. Oscillating Nernst-Ettingshausen effect in Bismuth across the quantum limit. https://doi.org/10.1103/physrevlett.98.166602

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