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arXiv · 0812.2866

The thermopower and Nernst Effect in graphene in a magnetic field

Joseph G. Checkelsky·N. P. Ong
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Abstract

We report measurements of the thermopower $S$ and Nernst signal $S_{yx}$ in graphene in a magnetic field $H$. Both quantities show strong quantum oscillations vs. the gate voltage $V_g$. Our measurements for Landau Levels of index $n\ne 0$ are in quantitative agreement with the edge-current model of Girvin and Jonson (GJ). The inferred off-diagonal thermoelectric conductivity $α_{yx}$ comes close to the quantum of Amps per Kelvin. At the Dirac point ($n=0$), however, the width of the peak in $α_{yx}$ is very narrow. We discuss features of the thermoelectric response at the Dirac point including the enhanced Nernst signal.

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Joseph G. Checkelsky, N. P. Ong. 2009-01-12. The thermopower and Nernst Effect in graphene in a magnetic field. https://doi.org/10.1103/physrevb.80.081413

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