Related papers: Bound States in Gapped Graphene with Impurities : …
We present a quantum analysis of the massless excitations in graphene with a charge impurity. When the effective charge exceeds a certain critical value, the spectrum is quantized and is unbounded from below. The corresponding eigenstates…
The effect of supercritical charge impurities in graphene is very similar to the supercritical atomic collapses in QED for Z > 137, but with a much lower critical charge. In this sense graphene can be considered as a natural testing ground…
We study theoretically the effects of short-range electron-electron interactions on the electronic structure of graphene, in the presence of single substitutional impurities. Our computational approach is based on the $\pi$ orbital…
We study the combined effect of a conical topological defect and a Coulomb charge impurity on the dynamics of Dirac fermions in gapped graphene. Beyond a certain strength of the Coulomb charge, quantum instability sets in, which demarcates…
The electronic energy spectrum of graphene electron subjected to a homogeneous magnetic field in the presence of a charged Coulomb impurity is studied analytically within two-dimensional Dirac-Weyl picture by using variational approach. The…
Bound electron states in impure graphene are considered. Short-range perturbations for defect and impurities of the types "local chemical potential" and "local gap" are taken into account.
We study the problem of the electron excitation spectrum in the presence of point-like and regularized Coulomb impurities in gapped graphene. To this end, we use the Dirac model and in the point-like case theory of self-adjoint extensions…
Recent optical conductivity experiments of doped graphene in the infrared regime reveal a strong background in the energy region between the intra and interband transitions difficult to explain within conventional pictures. We propose a…
We consider an effect of weak impurities on electronic properties of graphene within the functional renormalization-group approach. The energy dependences of the electronic self-energy and density of states near the neutrality point are…
In this paper, we numerically study the bound electron states induced by long range Coulomb impurity in gapped graphene and the quasi-bound states in supercritical region based on the lattice model. We present a detailed comparison between…
Bound and resonance electronic states in impure graphene are studied. Short-range perturbations for defects and impurities of the types "local chemical potential" and "local gap" are taken into account. Zero gap and non-zero gap kinds of…
In the low-energy two-band as well as four-band continuum models, we study the supercritical instability in gapped bilayer graphene in the field of a charged impurity. It is found that the screening effects are crucially important in…
We give an update of the situation concerning the effect of electron-electron interactions on the physics of a neutral graphene system at low energies. We revise old renormalization group results and the use of 1/N expansion to address…
The effects of the electron-electron interactions in a graphene layer are investigated. It is shown that short range couplings are irrelevant, and scale towards zero at low energies, due to the vanishing of density of states at the Fermi…
We consider the problem of electron energy states related to strongly localized potential of a single impurity in graphene. Our model simulates the effect of impurity atom substituting the atom of carbon, on the energy spectrum of electrons…
We formulate and solve the perhaps simplest two-body bound state problem for interacting Dirac fermions in two spatial dimensions. A two-body bound state is predicted for gapped graphene monolayers in the presence of weakly repulsive…
Based on the calculation and analysis of local Green functions of impurity atoms of low concentration in a two-dimensional graphene lattice, the conditions for the formation and characteristics of local discrete levels with energies lying…
We study optically-induced collective excitations of graphene in the presence of a strong perpendicular magnetic field and a single impurity. We determine the energies and absorption strengths of these excitations, which become localised on…
The Coulomb impurity problem of graphene, in the absence of a magnetic field, displays discrete scale invariance. Applying a magnetic field introduces a new magnetic length scale $\ell$ and breaks discrete scale invariance. Moreover, a…
The effect of substitution atoms on the energy spectrum and the electrical conductivity of graphene was investigated in a Lifshitz one-electron tight-binding model. It is established that the ordering of impurity atoms results in a gap in…