Related papers: 4He on a single graphene sheet
A single-layer graphene is synthesized on Cu foil in the absence of H2 flow by plasma enhanced chemical vapor deposition (PECVD). In lieu of an explicit H2 flow, hydrogen species are produced during methane decomposition process into their…
We examine the competition between adhesive and bending energies for few-layered graphene samples placed on rigid, microscale-corrugated substrates. Using atomic force microscopy, we show that the graphene undergoes a sharp "snap-through"…
The adsorption/desorption of ethene (C2H4), also commonly known as ethylene, on Fe3O4(001) was studied under ultrahigh vacuum conditions using temperature programmed desorption (TPD), scanning tunneling microscopy, x-ray photoelectron…
The possible occurrence of bound states of He-3 atoms in the vicinity of a weakly attractive substrate coated with a thin superfluid He-4film is investigated by first principle computer simulations. No evidence is seen of such bound states,…
We study the elasticity of perfect 4He at zero-temperature using the diffusion Monte Carlo method and a realistic semi-empirical pairwise potential to describe the He-He interactions. Specifically, we calculate the value of the elastic…
We find experimentally that the optical sheet conductance of graphite per graphene layer is very close to $(\pi/2)e^2/h$, which is the theoretically expected value of dynamical conductance of isolated monolayer graphene. Our calculations…
The hydrogen dynamics on a graphene sheet is studied in the presence of carbon vacancies. We analyze the motion of atomic H by means of molecular dynamics (MD) simulations, using a tight-binding Hamiltonian fitted to density-functional…
In this study, we use the density functional theory (DFT) calculations and the molecular dynamics (MD) simulations to investigate the performance of graphenylene--1 membrane for hydrogen ($H_2$) purification and helium ($He$) separation.…
Point Projection Microscopy (PPM) is used to image suspended graphene using low-energy electrons (100-200eV). Because of the low energies used, the graphene is neither damaged or contaminated by the electron beam. The transparency of…
Atomic layer deposition of ultrathin HfO2 on unmodified graphene from HfCl4 and H2O was investigated. Surface RMS roughness down to 0.5 nm was obtained for amorphous, 30 nm thick hafnia film grown at 180 degrees C. HfO2 was deposited also…
Graphene is considered a promising candidate to replace conventional transparent conductors due to its low opacity, high carrier mobility and flexible structure. Multi-layer graphene or stacked single layer graphenes have been investigated…
We have measured surface morphology and gas adsorption characteristics of uncompressed pyrolytic graphite sheet (uPGS) which is a candidate substrate for AC and DC superflow experiments on monolayers of 4He below T = 1 K. The PGS is a…
Computer simulations are employed to investigate the adsorption mechanisms of ethane on both homogeneous and inhomogeneous substrates. For homogeneous surfaces, the full range of surface phase transitions - from incomplete to complete…
We have investigated ozone adsorption on graphene using the ab initio density functional theory method. Ozone molecules adsorb on graphene basal plane with binding energy of 0.25 eV, and the physisorbed molecule can chemically react with…
Energetically the single sheet of graphite (graphene) is more stable than the nanotube. The energy difference between the two systems can be directly related to the strain energy involved in rolling up the graphene sheet to form the…
Thin $^4$He films adsorbed to weakly attractive substrates form nearly 2D layers. We describe the vortices in 2D superfluid $^4$He like quasiparticles. With the aid of a variational many-body calculation we estimate their inertial mass and…
We observe optical third harmonic generation from graphene and few-layer graphite flakes produced by exfoliation. The emission scales with the cube of the intensity of the incident near-infrared femtosecond pulses and has a wavelength that…
We experimentally investigate electrical transport properties of graphene, which is a two dimensional (2D) conductor with relativistic energy dispersion relation. By investigating single- and bi-layer graphene devices with different aspect…
Based on first principles calculation, the electronic properties of graphene on metal (Ti, Ca, Ni, Mn, Co, Fe, Cr, K) modified SiO2 substrate have been studied. The results of binding energies supported graphene indicate that the metal…
The kinetics of the sorption and the subsequent desorption of 4He by the starting graphite oxide (GtO) and the thermally reduced graphene oxide samples (TRGO, Treduction = 200, 300, 500, 700 and 900 C) have been investigated in the…