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arXiv · 1307.2257

The effect of electron dielectric response on the quantum capacitance of graphene in a strong magnetic field

Brian Skinner·G. L. Yu·A. V. Kretinin·A. K. Geim·K. S. Novoselov·B. I. Shklovskii
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Abstract

The quantum capacitance of graphene can be negative when the graphene is placed in a strong magnetic field, which is a clear experimental signature of positional correlations between electrons. Here we show that the quantum capacitance of graphene is also strongly affected by its dielectric polarizability, which in a magnetic field is wave vector-dependent. We study this effect both theoretically and experimentally. We develop a theory and numerical procedure for accounting for the graphene dielectric response, and we present measurements of the quantum capacitance of high-quality graphene capacitors on boron nitride. Theory and experiment are found to be in good agreement.

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Brian Skinner, G. L. Yu, A. V. Kretinin, A. K. Geim, K. S. Novoselov, B. I. Shklovskii. 2013-07-08. The effect of electron dielectric response on the quantum capacitance of graphene in a strong magnetic field. https://doi.org/10.1103/physrevb.88.155417

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