Related papers: Does Silicene on Ag(111) Have a Dirac Cone?
The oxidized Ag(111) surface has been studied by a combination of experimental and theoretical methods, scanning tunneling microscopy (STM), x-ray photoelectron spectroscopy (XPS), and density functional theory (DFT). A large variety of…
Strong band engineering in two-dimensional (2D) materials can be achieved by introducing moir\'e superlattices, leading to the emergence of various novel quantum phases with promising potential for future applications. Presented works to…
The electronic structure of graphene on Cu(111) and Cu(100) single crystals is investigated using low energy electron microscopy, low energy electron diffraction and angle resolved photoemission spectroscopy. On both substrates the graphene…
We have performed systematic angle-resolved photoemission spectroscopy of the topological crystalline insulator (TCI) Pb1-xSnxTe to elucidate the evolution of its electronic states across the topological phase transition. As previously…
Angle resolved photoemission spectroscopy (ARPES) studies were performed on two compounds (TlBiTe$_2$ and TlBiSe$_2$) from a recently proposed three dimensional topological insulator family in Thallium-based III-V-VI$_2$ ternary…
On the basis of first-principles calculations, we report that a novel interfacial atomic structure occurs between graphene and the surface of silicon carbide, destroying the Dirac point of graphene and opening a substantial energy gap…
Anisotropic bulk Dirac (or Weyl) cones in three dimensional systems have recently gained intense research interest as they are examples of materials with tilted Dirac (or Weyl) cones indicatig the violation of Lorentz invariance. In…
$\alpha$-GeTe(111) is a non-centrosymmetric ferroelectric (FE) material for which a significative lattice distortion combined with a strong spin-orbit interaction gives rise to giant Rashba split states in the bulk and at the surface, which…
Dirac fermions exist in many solid state systems including graphene, silicene and other two dimensional membranes such as are found in group VI dichalcogenides, as well as on the surface of some insulators where such states are protected by…
Two-dimensional Graphene is fascinating because of its unique electronic properties. From a fundamental perspective, one among them is the geometric phase structure near the Dirac points in the Brillouin zone, owing to the SU(2) nature of…
In the previous publications (E. Kogan and V. U. Nazarov, Phys. Rev. B {\bf 85}, 115418 (2012) and E. Kogan, Graphene {\bf 2}, 74 (2013)) we presented point group symmetry classification of energy bands in graphene. In the present note we…
Two-dimensional Dirac semimetals have attracted much attention because of their linear energy dispersion and non-trivial Berry phase. Graphene-like 2D Dirac materials are gapless only within certain approximations, e.g., if spin-orbit…
We present a joint experimental and theoretical determination of structures of Ag adatoms on the Ge(111) surface using low energy electron diffraction, low energy electron microscopy, scanning tunneling microscopy, and density functional…
A self-consisting gauge-theory approach to describe Dirac fermions on flexible surfaces with a disclination is formulated. The elastic surfaces are considered as embeddings into R^3 and a disclination is incorporated through a topologically…
We explore the hyperbolic band theory under a magnetic field for the first time. Our theory is a general extension of the conventional band theory defined on a Euclidean lattice into the band theory on a general hyperbolic lattice/Riemann…
The symmetries that protect massless Dirac fermions from a gap opening may become ineffective if the Dirac equation is discretized in space and time, either because of scattering between multiple Dirac cones in the Brillouin zone (fermion…
We investigate a planar heterostructure composed of two graphene films separated by a narrow-gap semiconductor ribbon. We show that there is no the Klein paradox when the Dirac points of the Brillouin zone of graphene are in a band gap of a…
Massive Dirac fermions are low-energy electronic excitations characterized by a hyperbolic band dispersion. They play a central role in several emerging physical phenomena such as topological phase transitions, anomalous Hall effects and…
We analyze the energy spectrum of graphene in the presence of spin-orbit coupling and a unidirectionally periodic Zeeman field, focusing on the stability and location of Dirac points it may support. It is found that the Dirac points at the…
The massless Dirac electrons found at topological insulator surfaces are thought to be influenced very little by weak, non-magnetic disorder. However, a resonance effect of strongly perturbing non-magnetic impurities has been theoretically…