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arXiv · 2211.02306

Quantized thermoelectric Hall plateau in the quantum limit of graphite as a nodal line semimetal

Andhika Kiswandhi·Tomotaka Ochi·Toshihiro Taen·Mitsuyuki Sato·Kazuhito Uchida·Toshihito Osada
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Abstract

We performed thermoelectric Hall conductivity $\alpha_{xy}$ measurements on single-crystal graphite in the quantum limit up to 13 T. Both electrical and thermoelectric transport measurements were performed on the same crystal to extract pure $\alpha_{xy}$, avoiding any sample quality dependence. The $\alpha_{xy}$ converges to a plateau in the quantum limit with a linear dependence on temperature. This behavior is analogous to the quantized thermoelectric Hall effect (QTHE) observed in three-dimensional Dirac/Weyl nodal-point semimetals, and experimentally confirms a theoretical proposal on the QTHE in semimetals with nodal lines as in graphite.

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Andhika Kiswandhi, Tomotaka Ochi, Toshihiro Taen, Mitsuyuki Sato, Kazuhito Uchida, Toshihito Osada. 2022-11-04. Quantized thermoelectric Hall plateau in the quantum limit of graphite as a nodal line semimetal. https://doi.org/10.1103/physrevb.107.195106

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