Related papers: Direct imaging of monovacancy-hydrogen complexes i…
We present a scanning tunneling microscopy (STM) study of a gently-graphitized 6H-SiC(0001) surface in ultra high vacuum. From an analysis of atomic scale images, we identify two different kinds of terraces, which we unambiguously attribute…
We characterize germanium-vacancy GeVn complexes in silicon using first-principles Density Functional Theory calculations with screening-dependent hybrid functionals. We report on the local geometry and electronic excited states of these…
We study the electronic structure of graphene with a single substitutional vacancy using a combination of the density-functional, tight-binding, and impurity Green's function approaches. Density functional studies are performed with the…
Adsorption of hydrogen atoms on a single graphite sheet (graphene) has been investigated by first-principles electronic structure means, employing plane-wave based, periodic density functional theory. A reasonably large 5x5 surface unit…
We provide a thorough study of a carbon divacancy, a fundamental but almost unexplored point defect in graphene. Low temperature scanning tunneling microscopy (STM) imaging of irradiated graphene on different substrates enabled us to…
Electronic instabilities at the crossing of the Fermi energy with a Van Hove singularity in the density of states often lead to new phases of matter such as superconductivity, magnetism or density waves. However, in most materials this…
Transmission electron microscopy (TEM) and scanning TEM (STEM) are indispensable tools for materials characterization. However, during a typical (S)TEM experiment, the sample is subject to a number of effects that can change its atomic…
Creating defects in graphene by hydrogenation, either to achieve hydrogen chemisorption or partial etching, is a way to open an electronic band gap in graphene. Understanding the range of stability conditions of partially etched or…
We study interfacial water trapped between a sheet of graphene and a muscovite (mica) surface using Raman spectroscopy and ultra-high vacuum scanning tunneling microscopy (UHV-STM) at room temperature. We are able to image the…
While defects are generally considered to be unavoidable in experiments, engineering them is also a way of manipulating the physical properties of materials. In this study, the role of periodically arranged single vacancy defects in…
A thorough spectroscopic characterisation of two samples of highly hydrogenated monolayer graphene transferred on nickel grids is herein reported. With X ray photoemission spectroscopy on the C 1s core-level, a 100$\%$ $sp^3$ distortion was…
X-ray photoelectron spectroscopy of graphene is important both for its characterization and as a model for other carbon materials. Despite great recent interest, the intrinsic photoemission of its single layer has not been unambiguously…
We analyze the nature of the single particle states, away from the Dirac point, in the presence of long-range charge impurities in a tight-binding model for electrons on a two-dimensional honeycomb lattice which is of direct relevance for…
Density functional calculations are employed to study the molecular dissociation of hydrogen on graphene, the diffusion of chemisorbed atomic species, and the electronic properties of the resulting hydrogen on graphene system. Our results…
We report a metal-insulator transition in disordered graphene with low coverages of hydrogen atoms. Hydrogen interacting with graphene creates short-range disorder and localizes states near the neutrality point. The energy range of…
A series of measurements using a novel technique called electrostatic-manipulation scanning tunneling microscopy were performed on a highly-oriented pyrolytic graphite (HOPG) surface. The electrostatic interaction between the STM tip and…
Artificial graphene consisting of honeycomb lattices other than the atomic layer of carbon has been shown to exhibit electronic properties similar to real graphene. Here, we reverse the argument to show that transport properties of real…
Recent scanning tunneling spectroscopy (STM) experiments display images with star and ellipsoidal like features resulting from unique geometrical arrangements of a few adsorbed hydrogen atoms on graphite. Based on first-principles STM…
High mobility single and few-layer graphene sheets are in many ways attractive as nanoelectronic circuit hosts but lack energy gaps, which are essential to the operation of field-effect transistors. One of the methods used to create gaps in…
The ability of atomic hydrogen to chemisorb on graphene makes the latter a promising material for hydrogen storage. Based on scanning tunneling microscopy techniques, we report on site-selective adsorption of atomic hydrogen on convexly…