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arXiv · 1206.2854

Coulomb Drag and Magnetotransport in Graphene Double Layers

Seyoung Kim·Emanuel Tutuc
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Abstract

We review the fabrication and key transport properties of graphene double layers, consisting of two graphene monolayers placed in close proximity, independently contacted, and separated by an ultra-thin dielectric. We outline a simple band structure model relating the layer densities to the applied gate and inter-layer biases, and show that calculations and experimental results are in excellent agreement both at zero and in high magnetic fields. Coulomb drag measurements, which probe the electron-electron scattering between the two layers reveal two distinct regime: (i) diffusive drag at elevated temperatures, and (ii) mesoscopic fluctuation-dominated drag at low temperatures. We discuss the Coulomb drag results within the framework of existing theories.

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Seyoung Kim, Emanuel Tutuc. 2012-06-13. Coulomb Drag and Magnetotransport in Graphene Double Layers. https://doi.org/10.1016/j.ssc.2012.04.032

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