Related papers: Superconductivity and antiferromagnetism in the tw…
We study the effects of a periodically varying electric field on the Hubbard model at half-filling on a triangular lattice. The electric field is incorporated through the phase of the nearest-neighbor hopping amplitude via the Peierls…
We have systematically studied superconducting instabilities in the repulsive Hubbard model for d-wave and p-wave pairing in various 2D and 3D lattices. Using fluctuation exchange approximation, we consider 3D face centered cubic lattice,…
Making use of symmetry properties and known exact results for the Hubbard Model on bipartite lattice, we show that (1) there is no phase separation for repulsive coupling at low dopings, (2) phase separation and superconductivity co-exist…
The half-filled attractive Hubbard model exhibits simultaneous charge density wave and superconducting order in its ground state. In this paper we explore the effect of disorder in the site energies on this degeneracy. We find that…
Using renormalization group and exact diagonalization of small clusters we investigate the ground state phase diagram of a two-dimensional extended Hubbard model with nearest-neighbor exchange interaction J, in addition to the local Coulomb…
We study the fluctuations responsible for pairing in the $d$-wave superconducting state of the two-dimensional Hubbard model at intermediate coupling within a cluster dynamical mean-field theory with a numerically exact quantum impurity…
The applicability of the Hartree-Fock and random phase approximations to models of strongly correlated electrons is discussed. The 2D Hubbard model is analyzed. An antiferromagnetic phase (at half filling) and Fermi liquid behavior (at low…
We study superconductivity in two-band models where one of the bands does or does not intersect the Fermi level depending on the parameter values. Applying a many-variable variational Monte-Carlo method for a Hubbard model on two-leg ladder…
We present an extension to the two-dimensional functional renormalization group to efficiently treat interactions on the surface or at interfaces of three-dimensional systems. As an application, we consider a semi-infinite stack of…
We investigate two-component ultracold fermions loaded into a decorated square lattice, which are described by the Hubbard model with repulsive interactions and nearest neighbor hoppings. By combining the real-space dynamical mean-field…
Using a recently developed renormalization group method for fermionic superfluids, we determine conditions for d-wave superconductivity in the two-dimensional Hubbard model at moderate interaction strength, and we compute the pairing gap in…
Applying the recently developed variational approach to Kohn-Luttinger superconductivity to the t-t' Hubbard model in two dimensions, we have found, for sizeable next-nearest neighbor hopping, an electron density controlled quantum phase…
Striped superconductivity with lattice distortions is investigated based on the three-band Hubbard model for high-Tc cuprates. A stable inhomogeneous striped state is determined in the low-temperature tetragonal (LTT) phase with lattice…
The ground state properties of random-exchange spin-1/2 Heisenberg antiferromagnets on the square lattice are investigated using a combination of quantum Monte Carlo simulations, exact numerical diagonalizations, and spin wave calculations.…
In this work, we revisit the phase diagram of the $t$-$t^\prime$-$\delta$ Fermi-Hubbard model on the square lattice to gain a more comprehensive understanding of this correlated model at half filling. This model has recently become a…
The paper examines part of the ground state diagram of the extended Hubbard model, with the on-site attraction U<0 and intersite repulsion W>0 in the presence of charge density waves, superconducting and $\eta$-superconducting order…
We study numerically the ground-state properties of the repulsive Hubbard model for spin-1/2 electrons on two-dimensional lattices with disordered on-site energies. The projector quantum Monte Carlo method is used to obtain very accurate…
We study the Hubbard model on a square lattice, using the dynamical vertex approximation and the parquet approximation. These methods allow us to describe the mutual interference of spin-fluctuations in the particle-hole channel and…
We present magnetic properties of the three-band Hubbard model in the para- and antiferromagnetic phase on a hypercubic lattice calculated with the Dynamical Mean-Field Theory (DMFT). To allow for solutions with broken spin-symmetry we…
We have studied the half-Heusler compound TbPdBi through resistivity, magnetization, Hall effect and heat capacity measurements. A semimetal behavior is observed in its normal state transport properties, which is characterized by a large…