Graphene, a two-dimensional carbon sheet, has attracted great interest due to its unique properties. To explore its practical applications, large-scale synthesis with controllable integration of individual graphene sheets is essential. To date, numerous approaches have been developed for graphene synthesis, including mechanical cleavage, epitaxial growth, and chemical vapor deposition. All of t...

We characterize the macroscopic effective mechanical behavior of a graphene sheet modeled by a hexagonal lattice of elastic bars, using Γ-convergence.

We demonstrate electrical control over coherent optical absorption in a graphene-based Salisbury screen consisting of a single layer of graphene placed in close proximity to a gold back reflector. The screen was designed to enhance light absorption at a target wavelength of 3.2 μm by using a 600 nm-thick, nonabsorbing silica spacer layer. An ionic gel layer placed on top of the screen was used ...

3D annealed SnO2/graphene sheet foams (ASGFs) are synthesized by in situ self-assembly of graphene sheets prepared by mild chemical reduction. L-ascorbyl acid is used to effectively reduce the SnO2 nanoparticles/graphene oxide colloidal solution and form the 3D conductive graphene networks. The annealing treatment contributes to the formation of the Sn-O-C bonds between the SnO2 nanoparticles a...

Graphene thin films have great potential to function as transparent electrodes in organic electronic devices, due to their excellent conductivity and high transparency. Recently, organic light-emitting diodes (OLEDs)have been successfully demonstrated to possess high luminous efficiencies with p-doped graphene anodes. However, reliable methods to fabricate n-doped graphene cathodes have been la...

To unleash the full potential of graphene in electronics and optoelectronics, high-quality graphene patterns on insulating substrates are required. However, existing methods generally follow a "synthesis + patterning" strategy, which are time consuming and costly for fabricating high-quality graphene patterns on desired substrates. We developed a nanofabrication process to deposit high-quality ...

Graphene’s unique symmetry between pand n-branches has enabled several interesting device applications; however, short-channel devices often exhibit degraded symmetry. We examine how graphene nanoribbon geometries can improve transfer characteristics and p–n symmetry, as well as reduce Dirac point shift for highly scaled graphene devices. RF graphene transistors utilizing a multiribbon channel ...

The graphene is a native two-dimensional crystal material consisting of a single sheet of carbon atoms. In this unique one-atom-thick material, the electron transport is ballistic and is described by a quantum relativistic-like Dirac equation rather than by the Schrödinger equation. As a result, a graphene barrier behaves very differently compared to a common semiconductor barrier. We show that...

We discuss various scattering mechanisms for Dirac fermions in single-layer graphene. It is shown that scattering on a short-range potential (e.g. due to neutral impurities) is mostly irrelevant for electronic quality of graphene, which is likely to be controlled by charged impurities and ripples (microscopic corrugations of a graphene sheet). The latter are an inherent feature of graphene due ...

Using thermally evaporated cesium carbonate (Cs2CO3) in an organic matrix, we present a novel strategy for efficient n-doping of monolayer graphene and a ∼90% reduction in its sheet resistance to ∼250 Ohm sq(-1). Photoemission spectroscopy confirms the presence of a large interface dipole of ∼0.9 eV between graphene and the Cs2CO3/organic matrix. This leads to a strong charge transfer based dop...