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Magnetothermal Conductivity of Highly Oriented Pyrolytic Graphite in the Quantum Limit

R. Ocaña·P. Esquinazi·H. Kempa·J. H. S. Torres·Y. Kopelevich
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Abstract

We report on the magnetic field (0T$ \le B \le 9$T) dependence of the longitudinal thermal conductivity $κ(T,B)$ of highly oriented pyrolytic graphite in the temperature range 5 K $\le T\le$ 20 K for fields parallel to the $c-$axis. We show that $κ(T,B)$ shows large oscillations in the high-field region (B > 2 T) where clear signs of the Quantum-Hall effect are observed in the Hall resistance. With the measured longitudinal electrical resistivity we show that the Wiedemann-Franz law is violated in the high-field regime.

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R. Ocaña, P. Esquinazi, H. Kempa, J. H. S. Torres, Y. Kopelevich. 2003-09-05. Magnetothermal Conductivity of Highly Oriented Pyrolytic Graphite in the Quantum Limit. https://doi.org/10.1103/physrevb.68.165408

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