Related papers: Electronic Instabilities of the AA-Honeycomb Bilay…
Bilayer honeycomb lattice, with inter-layer tunneling energy, has a parabolic dispersion relation, which causes the charge imbalance between two sublattices. Here, we investigate the metal-insulator and magnetic phase transitions on the…
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…
We calculate the dynamical conductivity of AA-stacked bilayer graphene as a function of frequency and in the presence of a finite chemical potential due to charging. Unlike the monolayer, we find a Drude absorption at charge neutrality in…
According to electronic structure theory, bilayer graphene is expected to have anomalous electronic properties when it has long-period moir\'e patterns produced by small misalignments between its individual layer honeycomb lattices. We have…
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…
In the presence of a finite interlayer displacement field bilayer graphene has an energy gap that is dependent on stacking and largest for the stable AB and BA stacking arrangements. When the relative orientations between layers are twisted…
We predict topological electron crystals driven by the interplay of interlayer Coulomb attraction and topological miniband physics in bilayer graphene--Mott insulator heterostructures. Charge transfer creates a charge neutral, mass…
In the present paper, we describe the antiferromagnetic and excitonic correlations in the AA-stacked bilayer graphene. We consider the applied external electric field potential to the structure which leads to the electronic charge imbalance…
The interplay between different types of disorder and electron-electron interactions in graphene planes is studied by means of Renormalization Group techniques. The low temperature properties of the system are determined by fixed points…
We derive ground state wave functions of superconducting instabilities on the honeycomb lattice induced by nearest-neighbor attractive interactions. They reflect the Dirac nature of electrons in the low-energy limit. For the order parameter…
Band structure determines the motion of electrons in a solid, giving rise to exotic phenomena when properly engineered. Drawing an analogy between electrons and photons, artificially designed optical lattices indicate the possibility of a…
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 derive electronic structure models for weakly interacting bilayers such as graphene-graphene and graphene-hexagonal boron nitride, based on density functional theory calculations followed by Wannier transformation of electronic states.…
Within the Hartree Fock- RPA analysis, we derive the spin wave spectrum for the weak ferromagnetic phase of the Hubbard model on the honeycomb lattice. Assuming a uniform magnetization, the polar (optical) and acoustic branches of the spin…
A striking series of experiments have observed superconductivity in Bernal-stacked bilayer graphene (BBG) when the energy bands are flattened by applying an electrical displacement field. Intriguingly, superconductivity manifests only at…
We study the stability and electronic structure of magic-angle twisted bilayer graphene on the hexagonal boron nitride (TBG/BN). Full relaxation has been performed for commensurate supercells of the heterostructures with different twist…
The nature of the insulating and superconducting states in twisted bilayer graphene systems is intensely debated. While many works seek for explanations in the few flat bands near the Fermi level, theory and a number of experiments suggest…
Conducting steady-states of doped bilayer graphene have a non-zero sublattice pseudospin polarization. Electron-electron interactions renormalize this polarization even at zero temperature, when the phase space for electron-electron…
A DFT-based investigation of rhombohedral (ABC)-type graphene stacks in finite static electric fields is presented. Electronic band structures and field-induced charge densities are compared with related literature data as well as with own…
We investigate the twisted bilayer graphene by a two-orbital Hubbard model on the honeycomb lattice. The model is studied near 1/4 band filling by using the singular-mode functional renormalization group theory. Spin-triplet $f$-wave…