Related papers: A contractor-renormalization study of Hubbard plaq…
In strongly correlated quantum materials, the behavior of charge carriers is dominated by strong electron-electron interactions. These can lead to insulating states with spin order, and upon doping to competing ordered states including…
We generalize the Cooper problem to the case of many interacting particles in the vicinity of the Fermi level in the presence of disorder. On the basis of this approach we study numerically the variation of the pair coupling energy in small…
We study the spectral function of two-leg Hubbard ladders with the time-dependent density matrix renormalization group method (tDMRG). The high-resolution spectrum displays features of spin-charge separation and a scattering continuum of…
Ferromagnetism in the t-t' Hubbard model is investigated on a square lattice. Correlation effects in the form of self-energy and vertex corrections are systematically incorporated within a spin-rotationally-symmetric scheme which explicitly…
We demonstrate that the infinite-$U$ triangular-lattice Hubbard model supports a superconducting state built from tightly bound Cooper pairs composed of two holes and one magnon ($2h1m$). Building on the seminal prediction of repulsively…
We extend and apply a recently introduced quasi-particle functional renormalisation group scheme to the two-dimensional Hubbard model with next-nearest-neighbour hopping and away from half filling. We confirm the generation of…
A two-dimensional model of interacting plaquettes is studied by means of the real space renormalization group approach. Interactions between the plaquettes are mediated solely by spin excitations on the plaquettes. Depending on the…
The equations of motion of pair-like excitations in the superconducting state are studied for various types of pairing using the random phase approximation. The collective modes are computed of a layered electron gas described by a $t-t'$…
Using a spin-rotation invariant six-slave boson representation, we study the square lattice Hubbard model with nearest-neighbor hopping $t$ and next-nearest neighbor hopping $t'$. We discuss the influence of $t'$ on the charge and magnetic…
We study the one-dimensional attractive Fermionic Hubbard model under the influence of periodic driving with the time-dependent density matrix renormalization group method. We show that the system can be driven into an unconventional…
Identifying materials hosting an excitonic insulator ground state has been one of the major pursuits in condensed matter physics in recent years. Promising candidates in transition metal chalcogenide compounds (TMC), including…
Extensive numerical studies have demonstrated that the two-dimensional single-band Hubbard model contains much of the key physics in cuprate high-temperature superconductors. However, there is no definitive proof that the Hubbard model…
We investigate the charge-order transition at zero temperature in a two-leg Hubbard ladder with additional nearest-neighbor Coulomb repulsion V using the Density Matrix Renormalization Group technique. We consider electron densities between…
A theoretical model for the reentrant charge-order transition in the manganites is examined. This transition is studied with a purely electronic model for the Mn electrons: the extended Hubbard model. The electron-phonon coupling results in…
We study the weak-coupling limit of the $t-t^\prime-U$ Hubbard model on a two-dimensional square lattice using a direct perturbative approach. Aided by symbolic computational tools, we compute the longitudinal density-density correlation…
We use resurgent analysis to study non-perturbative aspects of the one-dimensional, multicomponent Hubbard model with an attractive interaction and arbitrary filling. In the two-component case, we show that the leading Borel singularity of…
The formation of hole pairs in the planar t-J model is studied in the presence of independent {\it dynamic} vibrations of the in-plane oxygen atoms. In-plane (breathing modes) and out-of-plane (buckling modes) displacements are considered.…
The spin configuration induced by single holes and hole pairs doped into stoichiometric, antiferromagnetic cuprates is considered. Unrestricted Hartree-Fock calculations for the three-band Hubbard model are employed to study spin-polaron…
We investigate the nature of the insulating phases in a bilayer Hubbard model with intralayer coupling $t$ and interlayer coupling $t_{\perp}$ at large interaction strength $U/t$ and half-filling. We consider a dynamical cluster…
It is discussed some problems of normal states of high temperature superconductors (HTS's) with d-wave pairing and next suppositions: 1) at pseudogap temperature it occurs the dimensional crossover from 3D incoherent normal state to quasi…