相关论文: Imaging van Hove Singularity Heterogeneity in Over…
We demonstrate a new method to control the Fermi level around the van Hove singularity (VHS) in Li-intercalated graphene on the SiC substrate. By angle-resolved photoemission spectroscopy, we observed a clear Lifshitz transition in the…
Graphene is an ideal platform to study many-body effects due to its semimetallic character and the possibility to dope it over a wide range. Here we study the width of graphene's occupied $\pi$-band as a function of doping using…
Graphene is an excellent candidate for the next generation of electronic materials due to the strict two-dimensionality of its electronic structure as well as the extremely high carrier mobility. A prerequisite for the development of…
We study the effects of metallic doping on the electronic properties of graphene using density functional theory in the local density approximation in the presence of a local charging energy (LDA+U). The electronic properties are sensitive…
Since lattice strain and charge density affect various material properties of graphene, a reliable and efficient method is required for quantification of the two variables. While Raman spectroscopy is sensitive and non-destructive, its…
We study proximity effects in clean nanoscale superconductor-normal metal-superconductor (S$\mid$N$\mid$S) graphene heterostructures using a self-consistent numerical solution to the continuum Dirac Bogoliubov-de Gennes (DBdG) equations. We…
Tuning the charge carrier density of two-dimensional (2D) materials by incorporating dopants into the crystal lattice is a challenging task. An attractive alternative is the surface transfer doping by adsorption of molecules on 2D crystals,…
Experimental setups for charge transport measurements are typically not compatible with the ultra-high vacuum conditions for chemical doping, limiting the charge carrier density that can be investigated by transport methods. Field-effect…
The superconducting proximity effect induces pairing correlations in metallic systems via Andreev scattering. This effect is particularly intriguing in graphene, as it enables two-dimensional superconductivity that is tunable through…
Graphene monolayer is a material with zero band gap, because of which its applications in optoelectronics are limited. The question arises, can we modify the optoelectronic properties of graphene by doping it with other atoms? Synthesis of…
The band structure of graphene exhibits van Hove singularities (VHS) at doping x=+- 1/8 away from the Dirac point. Near the VHS, interactions effects, enhanced due to the large density of states, can give rise to various many-body phases at…
Recent studies show that two low-energy Van Hove singularities (VHSs) seen as two pronounced peaks in the density of states (DOS) could be induced in twisted graphene bilayer. Here, we report angle dependent VHSs of slightly twisted…
This study presents a method based on the total internal reflection and the phase-shifting interferometry for measuring the Van Hove singularities in strained graphene. A linearly polarized light passes through some quarter- and half-wave…
In this review we highlight recent theoretical and experimental work on sublattice asymmetric doping of impurities in graphene, with a focus on substitutional Nitrogen dopants. It is well known that one current limitation of graphene in…
We propose a unique way to control both bandgap and the magnetic properties of nanoscale graphene, which might prove highly beneficial for application in nanoelectronic and spintronic devices. We have shown that chemical doping by nitrogen…
Raman spectroscopy is a powerful tool for characterizing the local properties of graphene. Here, we introduce a method for evaluating unknown strain configurations and simultaneous doping. It relies on separating the effects of hydrostatic…
Since advanced Silicon-based device components are moderately chemically tunable, doped graphene has emerged as a promising candidate to replace this semiconducting material in flexible miniaturized electronic devices. Indeed, heteroatom…
Graphene and carbon nanotubes have extraordinary mechanical and electronic properties. Intrinsic line defects such as local non-hexagonal reconstructions or grain boundaries, however, significantly reduce the tensile strength, but feature…
We simulate the optical and electrical responses in gallium-doped graphene. Using density functional theory with a local density approximation, we simlutate the electronic band structure and show the effects of impurity doping (0-3.91\%) in…
We present a method to create and erase spatially resolved doping profiles in graphene-hexagonal boron nitride (hBN) heterostructures. The technique is based on photo-induced doping by a focused laser and does neither require masks nor…