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Related papers: Fermions on bilayer graphene: symmetry breaking fo…

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Bilayer graphene (BLG) offers a rich platform for broken symmetry states stabilized by interactions. In this work we study the phase diagram of BLG in the quantum Hall regime at filling factor $\nu=0$ within the Hartree-Fock approximation.…

Strongly Correlated Electrons · Physics 2017-12-27 Ganpathy Murthy , Efrat Shimshoni , Herbert Fertig

We revisit the effect of local interactions on the quadratic band touching (QBT) of Bernal stacked bilayer graphene models using renormalization group (RG) arguments and quantum Monte Carlo simulations of the Hubbard model. We present an RG…

Strongly Correlated Electrons · Physics 2016-08-23 Sumiran Pujari , Thomas C. Lang , Ganpathy Murthy , Ribhu K. Kaul

Using a combination of quantum Monte Carlo simulations, functional renormalization group calculations and mean-field theory, we study the Hubbard model on the Bernal-stacked honeycomb bilayer at half-filling as a model system for bilayer…

We study the effects of long and short-range electron-electron interactions in a graphene bilayer. Using a variational wavefunction technique we show that in the presence of long-range Coulomb interactions the clean bilayer is always…

Strongly Correlated Electrons · Physics 2009-11-11 Johan Nilsson , A. H. Castro Neto , N. M. R. Peres , F. Guinea

Both insulating and conducting electronic behaviors have been experimentally seen in clean bilayer graphene samples at low temperature, and there is still no consensus on the nature of the interacting ground state at half-filling and in the…

Strongly Correlated Electrons · Physics 2019-09-11 Jia Ning Leaw , Ho-Kin Tang , Pinaki Sengupta , Fakher F. Assaad , Igor F. Herbut , Shaffique Adam

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…

Strongly Correlated Electrons · Physics 2011-04-01 Andreas Sinner , Klaus Ziegler

We study the ballistic conductivity of graphene bilayer in the presence of next-nearest neighbor hoppings between the layers. An undoped and unbiased system was found in Ref. [1] to show a nonuniversal (length-dependent) conductivity…

Mesoscale and Nanoscale Physics · Physics 2014-08-12 Grzegorz Rut , Adam Rycerz

We use a functional renormalization group approach to study the instabilities due to electron-electron interactions in a bilayer honeycomb lattice model with AA stacking, as it might be relevant for layered graphene with this structure.…

Strongly Correlated Electrons · Physics 2014-07-22 David Sánchez de la Peña , Michael M. Scherer , Carsten Honerkamp

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…

Strongly Correlated Electrons · Physics 2014-01-20 Hong-Shuai Tao , Yao-Hua Chen , Heng-Fu Lin , Hai-Di Liu , Wu-Ming Liu

We study the quantum many-body ground states of electrons on the half-filled honeycomb lattice with short- and long-ranged density-density interactions as a model for graphene. To this end, we employ the recently developed truncated-unity…

Strongly Correlated Electrons · Physics 2017-12-06 David Sánchez de la Peña , Julian Lichtenstein , Carsten Honerkamp , Michael M. Scherer

Interactions among charge carriers in graphene can lead to the spontaneous breaking of multiple degeneracies. When increasing the number of graphene layers following rhombohedral stacking, the dominant role of Coulomb interactions becomes…

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…

Strongly Correlated Electrons · Physics 2020-12-21 Oskar Vafek , Jian Kang

The low-energy theory of interacting electrons on graphene's two-dimensional honeycomb lattice is derived and discussed. In particular, the Hubbard model in the large-N limit is shown to have a semi-metal - antiferromagnetic insulator…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Igor F. Herbut

AA-stacked bilayer graphene supports Fermi circles in its bonding and antibonding bands which coincide exactly, leading to symmetry-breaking in the presence of electron-electron interactions. We analyze a continuum model of this system in…

Mesoscale and Nanoscale Physics · Physics 2013-04-02 L. Brey , H. A. Fertig

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)…

Strongly Correlated Electrons · Physics 2012-09-26 Xin-Zhong Yan , C. S. Ting

Bilayer graphene in a magnetic field hosts a variety of ordered phases built from eight Landau levels close in energy to the neutrality point. These levels are characterized by orbital $n=0,1$, valley $\xi=+,-$ and spin…

Mesoscale and Nanoscale Physics · Physics 2020-05-25 Brett R. Green , Jorge O. Sofo

The competing ground states of bilayer graphene are studied by applying renormalization group techniques to a bilayer honeycomb lattice with nearest neighbor hopping. In the absence of interactions, the Fermi surface of this model at…

Mesoscale and Nanoscale Physics · Physics 2013-01-03 Kok Wee Song , Yung-Ching Liang , Stephan Haas

We study the effect of sublattice symmetry breaking on the electronic, magnetic and transport properties of two dimensional graphene as well as zigzag terminated one and zero dimensional graphene nanostructures. The systems are described…

Mesoscale and Nanoscale Physics · Physics 2013-05-30 D. Soriano , J. Fernández-Rossier

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…

Strongly Correlated Electrons · Physics 2007-07-11 D. T. Son

We explore Bernal bilayer graphene in the presence of long-range Coulomb interactions, short-range Hund's coupling, and proximity-induced Ising spin-orbit coupling using self-consistent Hartree-Fock simulations. We show that the interplay…

Mesoscale and Nanoscale Physics · Physics 2024-12-10 Jin Ming Koh , Alex Thomson , Jason Alicea , Étienne Lantagne-Hurtubise