Related papers: Ghost excitonic insulator transition in layered gr…

In the present paper, we consider the excitonic effects on the single particle normal density of states (DOS) in the bilayer graphene (BLG). The local interlayer Coulomb interaction is considered between the particles on the non-equivalent…

Many-body interactions can produce novel ground states in a condensed-matter system. For example, interacting electrons and holes can spontaneously form excitons, a neutral bound state, provided that the exciton binding energy exceeds the…

Topological Mott insulator (TMI) with spontaneous time-reversal symmetry breaking and nonzero Chern number has been discovered in a real-space effective model for twisted bilayer graphene (TBG) at 3/4 filling in the strong coupling limit.…

Bilayer graphene -- two coupled single graphene layers stacked as in graphite -- provides the only known semiconductor with a gap that can be tuned externally through electric field effect. Here we use a tight binding approach to study how…

Antidot lattices, defined on a two-dimensional electron gas at a semiconductor heterostructure, are a well-studied class of man-made structures with intriguing physical properties. We point out that a closely related system, graphene sheets…

Electronic properties of bilayer and multilayer graphene have generally been interpreted in terms of AB or Bernal stacking. However, it is known that many types of stacking defects can occur in natural and synthetic graphite; rotation of…

Mott insulators with a half-filled band of electrons on the triangular lattice have been recently studied in a variety of organic compounds. All of these compounds undergo transitions to metallic/superconducting states under moderate…

An energy gap can be opened in the electronic spectrum of graphene by lifting its sublattice symmetry. In bilayers, it is possible to open gaps as large as 0.2 eV. However, these gaps rarely lead to a highly insulating state expected for…

Topological excitonic insulators combine topological edge states and spontaneous exciton condensation, with dual functionality of topological insulators and excitonic insulators. Yet, they are very rare and little is known about their…

Using non-perturbative theoretical method, we address the problem of strong correlations in twisted bilayer-layer graphene at the magic angle. We concentrate on the solution without symmetry breaking, where conventional Mott insulating…

We consider a single layer graphene nanoribbon with armchair edges in a longitudinally constant external potential and point out that its transport properties can be described by means of an effective non-Hermitian Hamiltonian. We show that…

The low energy physics of both graphene and surface states of three-dimensional topological insulators is described by gapless Dirac fermions with linear dispersion. In this work, we predict the emergence of a "heavy" Dirac fermion in a…

The electronic properties of a material depend on the spatial freedom of the electron wavefunction. A well-known example is graphite, which is a conventional gapless semiconductor, while a single layer of it, graphene, exhibits extremely…

All-carbon heterostructures have been produced recently via focused ion beam patterning of single layer graphene. Amorphized graphene is similar to a graphene sheet in which some hexagons are replaced by a combination of pentagonal,…

We investigate the electronic structure of terraces of single layer graphene (SLG) by scanning tunneling microscopy (STM) on samples grown by thermal decomposition of 6H-SiC(0001) crystals in ultra-high vacuum. We focus on the perturbations…

Graphene, a two-dimensional crystal made of carbon atoms, provides a new and unexpected bridge between low and high-energy physics. The field has evolved very fast and very good reviews are already available in the literature. Graphene…

Strongly correlated quantum matter exhibits a rich variety of remarkable properties, but the organizing principles that underlie the behavior remain to be established. Graphene heterostructures, which can host narrow moire electron bands…

We show theoretically that an undoped carbon nanotube might be an excitonic insulator---the long-sought phase of matter proposed by Keldysh, Kohn and others fifty years ago. We predict that the condensation of triplet excitons, driven by…

We investigate the magnetism in graphite by controlled oxidation. Our approach renders graphite an insulator while maintaining its structure. Fourier transform infrared spectroscopy and X-ray absorption near edge structure spectra reveal…

Intrinsic rhombohedral graphene hosts an unusual low-energy electronic wavefunction, predominantly localized at its outer crystal faces with negligible presence in the bulk. Increasing the number of graphene layers amplifies the density of…