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arXiv · 1105.1801

Capacitance of Graphene Bilayer as a Which-Layer Probe

Andrea F. Young·Leonid S. Levitov
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Abstract

The unique capabilities of capacitance measurements in bilayer graphene enable probing of layer-specific properties that are normally out of reach in transport measurements. Furthermore, capacitance measurements in the top-gate and penetration field geometries are sensitive to different physical quantities: the penetration field capacitance probes the two layers equally, whereas the top gate capacitance preferentially samples the near layer, resulting in the "near-layer capacitance enhancement" effect observed in recent top-gate capacitance measurements. We present a detailed theoretical description of this effect and show that capacitance can be used to determine the equilibrium layer polarization, a potentially useful tool in the study of broken symmetry states in graphene.

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Andrea F. Young, Leonid S. Levitov. 2011-05-09. Capacitance of Graphene Bilayer as a Which-Layer Probe. https://doi.org/10.1103/physrevb.84.085441

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