62 citations · 537 across the 37 of their papers we have counts for
37 papers
Finite temperatures and flat bands: the Hubbard model on three-dimensional Lieb lattices
Lucas O. Lima, Julián Faúndez, Natanael C. Costa +1
We investigate some thermodynamic and magnetic properties of the Hubbard model on two three-dimensional extensions of the Lieb lattice: the perovskite Lieb lattice (PLL) and the la…
The extended Hubbard model on a honeycomb lattice
Welberth Kennedy, Sebastião dos Anjos Sousa-Júnior, Natanael C. Costa +1
The lack of both nesting and a van Hove singularity at half filling, together with the presence of Dirac cones makes the honeycomb lattice a special laboratory to explore strongly…
Increasing superconducting by layering in the attractive Hubbard model
Rodrigo A. Fontenele, Natanael C. Costa, Thereza Paiva +1
The attractive Hubbard model has become a model readily realizable with ultracold atoms on optical lattices. However, the superconducting (superfluid) critical temperatures, '…
Multifractal critical phase driven by coupling quasiperiodic systems to electromagnetic cavities
Thales F. Macedo, Julián Faúndez, Raimundo R. dos Santos +2
We theoretically investigate criticality and multifractal states in a one-dimensional Aubry-Andre-Harper model coupled to electromagnetic cavities. We focus on two specific cases w…
Magnetism and metal-insulator transitions in the anisotropic kagome lattice
Lucas O. Lima, Andressa R. Medeiros-Silva, Raimundo R. dos Santos +2
The interest in the physical properties of kagome lattices has risen considerably. In addition to the synthesis of new materials, the possibility of realizing ultracold atoms on an…
The half-filled extended Hubbard model on a square lattice: Phase boundaries from determinant quantum Monte Carlo simulations
Sebastião dos Anjos Sousa-Júnior, Natanael C. Costa, Raimundo R. dos Santos
The extended Hubbard model (EHM) describes fermions on a lattice coupled through on-site, , and first-neighbor, , interactions. In the context of high- cuprates, antifer…
Magnetic impurities in a charge-ordered background
Sebastião dos Anjos Sousa-Júnior, Raimundo R. dos Santos, Natanael C. Costa
We investigate how magnetic impurities may affect a system exhibiting charge-density wave (CDW) in its ground state. We consider a disordered Hubbard-Holstein model with a homogene…
Magnetism and metal-insulator transitions in the Rashba-Hubbard model
Welberth Kennedy, Sebastião dos Anjos Sousa Júnior, Natanael C. Costa +1
The nature of metal-insulator and magnetic transitions is still a subject under intense debate in condensed matter physics. Amongst the many possible mechanisms, the interplay betw…
Unsupervised machine learning approaches to the -state Potts model
Andrea Tirelli, Danyella O. Carvalho, Lucas A. Oliveira +3
In this paper with study phase transitions of the -state Potts model, through a number of unsupervised machine learning techniques, namely Principal Component Analysis (PCA), $k…
Percolation on Lieb lattices
W. S. Oliveira, J. Pimentel de Lima, Natanael C. Costa +1
We study site- and bond-percolation on a class of lattices referred to as Lieb lattices. In two dimensions the Lieb lattice (LL) is also known as the decorated square lattice, or a…
Superconducting Kondo phase in an orbitally-separated bilayer
Sebastião dos Anjos Sousa-Júnior, José P. de Lima, Natanael C. Costa +1
The nature of superconductivity in heavy-fermion materials is a subject under intense debate, and controlling this many-body state is central for its eventual understanding. Here,…
A kaleidoscope of phases in the dipolar Hubbard model
Tiago Mendes-Santos, Rubem Mondaini, Thereza Paiva +1
We investigate the emergence of a myriad of phases in the strong coupling regime of the dipolar Hubbard model in two dimensions. By using a combination of numerically unbiased meth…
Determinant Quantum Monte Carlo Study of Exhaustion in the Periodic Anderson Model
Lufeng Zhang, Tianxing Ma, Natanael C. Costa +2
The Kondo and Periodic Anderson models describe many of the qualitative features of local moments coupled to a conduction band, and thereby the physics of materials such as the hea…
Coherence Temperature in the Diluted Periodic Anderson Model
N. C. Costa, T. Mendes-Santos, T. Paiva +3
The Kondo and Periodic Anderson Model (PAM) are known to provide a microscopic picture of many of the fundamental properties of heavy fermion materials and, more generally, a varie…
Compressible Ferrimagnetism in the depleted Periodic Anderson Model
N. C. Costa, M. V. Araújo, J. P. Lima +3
Tight-binding Hamiltonians with single and multiple orbitals exhibit an intriguing array of magnetic phase transitions. In most cases the spin ordered phases are insulating, while…
A mean-field approach to Kondo-attractive-Hubbard model
N. C. Costa, J. P. Lima, T. C. L. Paiva +2
With the purpose of investigating coexistence between magnetic order and superconductivity, we consider a model in which conduction electrons interact with each other, via an attra…
Ferromagnetism beyond Lieb's theorem
Natanael C. Costa, Tiago Mendes-Santos, Thereza Paiva +2
The noninteracting electronic structures of tight binding models on bipartite lattices with unequal numbers of sites in the two sublattices have a number of unique features, includ…
Impurities near an Antiferromagnetic-Singlet Quantum Critical Point
T. Mendes, N. Costa, G. Batrouni +4
Heavy fermion systems, and other strongly correlated electron materials, often exhibit a competition between antiferromagnetic (AF) and singlet ground states. Using exact Quantum M…
Spiral magnetic phases on the Kondo Lattice Model: A Hartree-Fock approach
Natanael de Carvalho Costa, José Pimentel de Lima, Raimundo R. dos Santos
We study the Kondo Lattice Model (KLM) on a square lattice through a Hartree-Fock approximation in which the local spins are treated semi-classically, in the sense that their avera…
Size and shape of Mott regions for fermionic atoms in a two-dimensional optical lattice
Tiago Mendes-Santos, Thereza Paiva, Raimundo R. dos Santos
We investigate the harmonic-trap control of size and shape of Mott regions in the Fermi Hubbard model on a square optical lattice. The use of Lanczos diagonalization on clusters wi…
Finite-size effects in transport data from Quantum Monte Carlo simulations
Rubem Mondaini, K. Bouadim, Thereza Paiva +1
We have examined the behavior of the compressibility, the dc-conductivity, the single-particle gap, and the Drude weight as probes of the density-driven metal-insulator transition…
Magnetic exchange mechanism for electronic gap opening in graphene
T. G. Rappoport, M. Godoy, B. Uchoa +2
We show within a local self-consistent mean-field treatment that a random distribution of magnetic adatoms can open a robust gap in the electronic spectrum of graphene. The electro…
Suppression of Anderson localization of light and Brewster anomalies in disordered superlattices containing a dispersive metamaterial
D. Mogilevtsev, F. A. Pinheiro, R. R. dos Santos +2
Light propagation through 1D disordered structures composed of alternating layers, with random thicknesses, of air and a dispersive metamaterial is theoretically investigated. Both…
Finite-size scaling behavior in trapped systems
S. L. A. de Queiroz, R. R. dos Santos, R. B. Stinchcombe
Numerical transfer-matrix methods are applied to two-dimensional Ising spin systems, in presence of a confining magnetic field which varies with distance to a "trap ce…