The quantum capacitance effect in graphene can readily be observed experimentally due to the low density of states near the Dirac energy. In particular, in metal-oxide-graphene structures with thin, high-K dielectrics, the quantum capacitance strongly affects the measurable capacitance as a function of gate voltage.

In this work, we show how the quantum capacitance can be utilized to understand numerous properties of graphene, the surrounding dielectrics and even absorbed molecules on the graphene surface. Furthermore, we show that the quantum capacitance can be utilized to realize numerous novel graphene-based devices, including wireless sensors and optical modulators. Finally, the prospects for future materials-related investigations and device applications of quantum capacitance in graphene are described.

Steven J Koester

University of Minnesota

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