Related papers: Variational approach to the excitonic phase transi…
Motivated by the physics of graphene, we consider a model of N species of 2+1 dimensional four-component massless Dirac fermions interacting through a 3D instantaneous Coulomb interaction. We show that in the limit of infinitely strong…
We consider the optical properties of the half-filled AB-stacked bilayer graphene with the excitonic pairing and condensation between the layers. Both intra and interlayer local Coulomb interaction effects have been taken into account and…
We use the Gutzwiller method to investigate the importance of the on-site Coulomb interaction in graphene. We apply it to Hubbard Hamiltonian to study the renormalization of the kinetic energy in graphene due to the on-site Coulomb…
We investigate the excitonic instability in the theory of Dirac fermions in graphene with long-range Coulomb interaction. We analyze the electron-hole vertex relevant for exciton condensation in the ladder approximation, showing that it…
We compute the renormalization group flow of the long-ranged electron-electron interaction at the Gross-Neveu quantum critical point between the semimetal and the excitonic insulator in graphene, perturbatively in the small parameter…
We consider the effect of the Coulomb interaction in strained graphene using tight-binding approximation together with the Hartree-Fock interactions. The many-body energy dispersion relation, anisotropic Fermi velocity renormalization and…
We address the problem of an unscreened Coulomb charge in graphene, and calculate the local density of states and displaced charge as a function of energy and distance from the impurity. This is done non-perturbatively in two different…
We argue that the unscreened Coulomb interaction in graphene provides a positive, universal, and logarithmic correction to scaling of zero-temperature conductivity with frequency. The combined effect of the disorder due to wrinkling of the…
The gap generation is studied in suspended clean graphene in the continuum model for quasiparticles with the Coulomb interaction. We solve the gap equation with the dynamical polarization function and show that, comparing to the case of the…
The dynamics of symmetry breaking responsible for lifting the degeneracy of the Landau levels in the integer quantum Hall effect in graphene is studied in a low-energy model with the Coulomb interaction. The gap equation for Dirac…
A fully selfconsistent treatment for gap generation and Coulomb screening in excitonic insulators is presented. The method is based on the equations of motion for the relevant dynamical variables combined with a variational approach.…
There is an interesting proposal that the long-range Coulomb interaction in suspended graphene can generate a dynamical gap, which leads to a semimetal-insulator phase transition. We revisit this problem by solving the self-consistent…
Low-energy electronic structure of (unbiased) bilayer graphene is made of two Fermi points with quadratic dispersions, if trigonal-warping and other high order contributions are ignored. We show that as a result of this qualitative…
The optical response and the ground state of graphene and graphene-like systems are determined self-consistently. Deriving equations of motion for the basic variables, graphene Bloch equations are introduced and combined with a variational…
The supercritical instability in a system of two identical charged impurities in gapped graphene described in the continuous limit by the two-dimensional Dirac equation has been studied. The case where the charge of each impurity is…
An anisotropic flat band fermion system with a novel dispersion that is linear along one direction and cubic along another is proposed in Phys. Rev. X. 13, 021012 (2023). We study the effects of Coulomb interaction in this fermion system by…
The quasi-2D electrons in graphene behave as massless fermions obeying a Dirac-Weyl equation in the low-energy regime near the two Fermi points. The stability of spin-polarized phases (SPP) in graphene is considered. The exchange energy is…
The electron-electron interactions effects on the shape of the Fermi surface of doped graphene are investigated. The actual discrete nature of the lattice is fully taken into account. A $\pi$-band tight-binding model, with nearest-neighbor…
We present results for the equation of state of a graphene-like model in an effort to understand the properties of its quantum phase transition. The N_f fermion species interact through a three dimensional instantaneous Coulomb potential.…
We address the computation of physical observables in graphene in the presence of Coulomb interactions of density-density type modeled with a static Coulomb potential within a quantum field theory perturbative renormalization scheme. We…