相关论文: Absorptive pinhole collimators for ballistic Dirac…
We theoretically demonstrate the capability of a ferromagnetic-normal (FN) interface in graphene to focus an electron-wave with a certain spin direction. The essential feature is the negative refraction Klein tunneling, which is…
Graphene bilayer systems are known to exhibit a band gap when the layer symmetry is broken, by applying a perpendicular electric field. The resulting band structure resembles that of a conventional semiconductor with a parabolic dispersion.…
We report that the {\pi}-electrons of graphene can be spin-polarized to create a phase with a significant spin-orbit gap at the Dirac point (DP) using a graphene-interfaced topological insulator hybrid material. We have grown epitaxial…
Twisted bilayer graphene with a twist angle of around 1.1{\deg} features a pair of isolated flat electronic bands and forms a strongly correlated electronic platform. Here, we use scanning tunneling microscopy to probe local properties of…
Atomically thin two-dimensional layer of honeycomb crystalline carbon known as graphene is a promising system for electronics. It has a point-like Fermi surface, which is very sensitive to external potentials. In particular, Zeeman magnetic…
The unusual electronic properties of graphene, which are a direct consequence of its two-dimensional (2D) honeycomb lattice, have attracted a great deal of attention in recent years. Creation of artificial lattices that recreate graphene's…
Dirac-electronic tunneling and nonlinear transport properties with both finite and zero energy bandgap are investigated for graphene with a tilted potential barrier under a bias. For validation, results from a finite-difference based…
We present a paradigm for integrated photonic devices based upon broadband slab-confined collimated beams that are launched with half-Maxwell fisheye lenses. Although it is challenging to match to the low-index focus of the lens whilst…
We study the tunneling of chiral electrons in graphene through a region where the electronic spectrum changes from the usual linear dispersion to a hyperbolic dispersion, due to the presence of a gap. It is shown that contrary to the…
Many of the proposed future applications of graphene require the controlled introduction of defects into its perfect lattice. Energetic ions provide one way of achieving this challenging goal. Single heavy ions with kinetic energies in the…
The response of Dirac fermions to a Coulomb potential is predicted to differ significantly from the behavior of non-relativistic electrons seen in traditional atomic and impurity systems. Surprisingly, many key theoretical predictions for…
Electron interferometry with quantum Hall edge channels holds promise for probing and harnessing exotic exchange statistics of non-Abelian anyons. In semiconductor heterostructures, however, quantum Hall interferometry has proven…
Band structure determines the motion of electrons in a solid, giving rise to exotic phenomena when properly engineered. Drawing an analogy between electrons and photons, artificially designed optical lattices indicate the possibility of a…
In a Dirac semimetal, the conduction and valence bands contact only at discrete (Dirac) points in the Brillouin zone (BZ) and disperse linearly in all directions around these critical points. Including spin, the low energy effective theory…
Recently, the most intensely studied objects in the electronic theory of solids have been strongly correlated systems and graphene. However, the fact that the Dirac bands in graphene are made up of $sp^{2}$-electrons, which are subject to…
When an ionic liquid adsorbs onto a porous electrode, its ionic arrangement is deeply modified due to a screening of the Coulombic interactions by the metallic surface and by the confinement imposed upon it by the electrode's morphology. In…
We present first-principles calculations of many-electron effects on the optical response of graphene, bilayer graphene, and graphite employing the GW-Bethe Salpeter equation approach. We find that resonant excitons are formed in these…
To fully utilize graphene's remarkable optical properties for optoelectronic applications, it needs to be integrated in planar photonic systems. Here, we demonstrate integration of graphene on silicon photonic circuits and precise…
The coupling of charge carrier motion and pseudospin via chirality for massless Dirac fermions in monolayer graphene has generated dramatic consequences, such as the unusual quantum Hall effect and Klein tunneling. In bilayer graphene,…
We present measurements of transmission and reflection spectra of a microwave photonic crystal composed of 874 metallic cylinders arranged in a triangular lattice. The spectra show clear evidence of a Dirac point, a characteristic of a…