相关论文: Spontaneous symmetry breaking and Lifshitz transit…

We develop a two stage renormalization group which connects the continuum Hamiltonian for twisted bilayer graphene at length scales shorter than the moire superlattice period to the Hamiltonian for the active narrow bands only which is…

The non-interacting energy spectrum of graphene and its bilayer counterpart consists of multiple degeneracies owing to the inherent spin, valley and layer symmetries. Interactions among charge carriers are expected to spontaneously break…

With the two-band continuum model, we study the broken inversion and time-reversal symmetry state of electrons with finite-range repulsive interactions in bilayer graphene. With the analytical solution to the mean-field Hamiltonian, we…

We study the renormalization of the effective mass and trigonal warping of bilayer graphene by the electron-electron interaction. One consequence of such a renormalization in the low-energy bands of a bilayer crystal consists of a small…

The nematic phase transition in electronic liquids, driven by Coulomb interactions, represents a new class of strongly correlated electronic ground states. We studied suspended samples of bilayer graphene, annealed so that it achieves very…

We study effects of a repulsive Coulomb interaction on the spectral gap in monolayer and bilayer graphene in the vicinity of the charge neutrality point by employing the functional renormalization-group technique. In both cases Coulomb…

On a lattice model, we study the possibility of existence of gapped broken inversion symmetry phase (GBISP) of electrons with long-range Coulomb interaction in bilayer graphene using both self-consistent Hartree-Fock approximation (SCHFA)…

Application of the magnetic field parallel to the plane of the graphene sheet leads to the formation of electron- and hole-like Fermi surfaces. Such situation is shown to be unstable with respect to the formation of an excitonic condensate…

We analyze the phase diagram of twisted graphene bilayers near a magic angle. We consider the effect of the long range Coulomb interaction, treated within the self consistent Hartree-Fock approximation, and we study arbitrary band fillings.…

We show that topology of the low-energy band structure in bilayer graphene critically depends on mechanical deformations of the crystal which may easily develop in suspended graphene flakes. We describe the Lifshitz transition that takes…

It is shown theoretically that the renormalization of the electron energy spectrum of bilayer graphene with a strong high-frequency electromagnetic field (dressing field) results in the Lifshitz transition - the abrupt change in the…

Graphene is a two dimensional crystal of carbon atoms with fascinating electronic and morphological properties. The low energy excitations of the neutral, clean system are described by a massless Dirac Hamiltonian in (2+1) dimensions which…

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…

We devote this work to the study of the mean-field phase diagram of the $\nu=0$ quantum Hall state in bilayer graphene and the computation of the corresponding neutral collective modes, extending the results of recent works in the…

We develop a theory for quantum phases and quantum multicriticality in bilayer graphene in the presence of an explicit energy gap in the non-interacting spectrum by extending previous renormalization group (RG) analyses of electron-electron…

We report on our studies of interacting electrons in bilayer graphene in a magnetic field. We demonstrate that the long range Coulomb interactions between electrons in this material are highly important and account for the band asymmetry in…

Inter-Landau-level transitions in the bilayer graphene at high perpendicular magnetic field at the filling-factor v<<1 have been studied. The next-nearest-neighbor transitions, energy difference between dimer and non-dimer sites and layer…

Using mean-field theory, we determine the electronic phase diagram of undoped AB-stacked bilayer graphene in the presence of a transverse electric field. In addition to multiple competing electronic instabilities characterized by excitonic…

We theoretically consider bilayers of two dimensional (2D) electron gases as in semiconductor quantum wells, and investigate possible spontaneous symmetry breaking transitions at low carrier densities driven by interlayer Coulomb…

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…