Coulomb drag and magnetotransport in graphene double layers

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.

► We present the fabrication of graphene double layers separated by an ultra-thin dielectric. ► We present individual layer resistivity measurements at zero and in high magnetic fields. ► We present Coulomb drag measurements in graphene as a function of temperature and layer density.