Related papers: Kekule-distortion-induced Exciton instability in g…
The effects of the electromagnetic (e.m.) electron-electron interactions in half-filled graphene are investigated in terms of a lattice gauge theory model. By using exact Renormalization Group methods and lattice Ward Identities, we show…
Exciton instability in graphene bilayer systems is studied in the case of a short-ranged Coulomb interaction and a finite voltage difference between the layers. Self-consistent exciton gap equations are derived and solved numerically and…
Kekul\'e phases are Peierls-like lattice distortions in graphene that are predicted to host novel electronic states beyond graphene (1-8). Although the Kekul\'e phases are realized in graphene through introducing electron-electron…
In this Ph.D. thesis a model for graphene in presence of quantized electromagnetic interactions is introduced. The zero and low temperature properties of the model are studied using rigorous renormalization group methods and lattice Ward…
Fractional charges are one of the wonders of the fractional quantum Hall effect, a liquid of strongly correlated electrons in a large magnetic field. Fractional excitations are also anticipated in two-dimensional crystals of non-interacting…
Two-dimensional quantum materials offer a robust platform for investigating the emergence of symmetry-broken ordered phases owing to the high tuneability of their electronic properties. For instance, the ability to create new electronic…
The deposition of a two-dimensional material on the surface of a three-dimensional crystal can generate superlattices with electronic properties modified through the proximity spin-orbit effect. In this study, we found that Kekul\'e…
At half filling, the electronic structure of graphene can be modelled by a pair of free two-dimensional Dirac fermions. We explicitly demonstrate that in the presence of a geometrically induced gauge field, an everywhere-real Kekule…
Twisted bilayer graphenes with magical angle exhibit strongly correlated electronic properties because of the isolated flat band at the Fermi level. We studied the twisted bilayer graphene with substrates on both layers. The substrate…
This work investigates the Floquet dynamics of electrons and excitons (particle-hole pairs) in a Dirac material referred to as Kekul\'e-distorted graphene. Specifically, we examine the role played by a high frequency driving electromagnetic…
We provide numerical evidence that a Kelvin-Helmholtz instability occurs in the Dirac fluid of electrons in graphene and can be detected in current experiments. This instability appears for electrons in the viscous regime passing though a…
We study the effect of a uniform pseudomagnetic field, induced by a strain in a monolayer and double layer of gapped graphene, acting on excitons. For our analysis it is crucial that the pseudomagnetic field acts on the charges of the…
Employing tight-binding model we investigate the effects of a uniform Y-shaped Kekule lattice distortion on the electronic spectrum and optical conductivity of graphene. We derive a low-energy effective Hamiltonian which is found to be in…
We propose a chiral symmetry restoration mechanism in monolayer graphene, in analogy with the strongly coupled gauge theory. The chiral (sublattice) symmetry of graphene, which is spontaneously broken under the effectively strong Coulomb…
Breaking the intrinsic chirality of quasiparticles in graphene enables the emergence of new and intriguing phases. One such paradigmatic example is the bond density wave, which leads to a Kekul\'{e}-ordered structure and underpins exotic…
Using density-functional theory, we calculate the electronic bandstructure of single-layer graphene on top of hexagonal In_2Te_2 monolayers. The geometric configuration with In and Te atoms at centers of carbon hexagons leads to a Kekule'…
We consider a model of Dirac fermions coupled to flexural phonons to describe a graphene sheet fluctuating in dimension $2+d$. We derive the self-consistent screening equations for the quantum problem, exact in the limit of large $d$. We…
We show that the dipole moment of an exciton is uniquely determined by the quantum geometry of its eigenstates, and demonstrate its intimate connection with a quantity we call the Quantum Geometric Dipole (QGD). The QGD arises naturally in…
The formation of a superlattice in graphene can serve as a way to modify its electronic bandstructure and thus to engineer its electronic transport properties. Recent experiments have discovered a Kekul\'e bond ordering in graphene…
Electron interactions in undoped bilayer graphene lead to instability of the gapless state, `which-layer' symmetry breaking, and energy gap opening at the Dirac point. In contrast to single layer graphene, the bilayer system exhibits…