Related papers: Hole on a stripe in a spinless fermion model
We show that pronounced modulations in spin and charge densities can be induced by the insertion of a single hole in an otherwise half-filled 2-leg Hubbard ladder. Accompanied with these modulations is a loosely bound structure of the doped…
We study repulsive Hubbard and t-J type systems on a square lattice (long believed to capture certain quintessential aspects of the high temperature superconductors). These models (alongside the parent compounds of the high temperature…
The problem of finding the minimum-energy configuration of particles on a lattice, subject to a generic short-ranged repulsive interaction, is studied analytically. The study is relevant to charge ordered states of interacting fermions, as…
We present a unified account for the coupled single-hole- and spin-dynamics in the spin-gap phase of dimerized and frustrated spin-chains and two-leg spin ladders. Based on the strong dimer-limit of a one-dimensional $t_123$-$J_123$-model a…
We investigate a system of fermions on a two-dimensional optical square lattice in the strongly repulsive coupling regime. In this case, the interactions can be controlled by laser intensity as well as by Feshbach resonance. We compare the…
We show that many observable properties of high temperature superconductors can be obtained in the frameworks of one-dimensional self-consistent model with included superconducting correlations. Analytical solutions for spin, charge and…
The two-orbital Hubbard model for the pnictides is studied numerically using the real-space Hartree-Fock approximation on finite clusters. Upon electron doping, states with a nonuniform distribution of charge are stabilized. The observed…
We establish a novel mechanism of stripe formation in doped systems with alternating $t_{2g}$ orbital order --- the stripe takes the form of a ferro-orbitally ordered domain wall separating domains with staggered order and allowing for…
The problems of charge stripe formation, spin-charge separation, and stability of the antiphase domain wall (ADW) associated with a stripe are addressed using an analytical approach to the t-J_z model. We show that a metallic stripe…
We study a model of spinless fermions on the honeycomb lattice with nearest-neighbor exclusion and extended repulsive interactions that exhibits `lattice supersymmetry' [P. Fendley, K. Schoutens, and J. de Boer, Phys. Rev. Lett. 90, 120402…
The microscopic structure of a charge stripe in an antiferromagnetic insulator is studied within the t-Jz model using analytical and numerical approaches. We demonstrate that a stripe in an antiferromagnet should be viewed as a system of…
We show that a system of spinless Fermi particles, localized on the sites of the Bethe lattice with coordination number z and interacting through a repulsive nearest-neighbor interaction, exhibits a phase transition to a charge-ordered…
We investigate the phase separated inhomogeneous charge and spin states in magnetic oxides. In particular, we study one dimensional harmonic waves and stripe structures. We show that harmonic spin charge waves are unstable and inevitably…
The 2D Hubbard model with large repulsion is a central and yet unsolved problem in condensed matter physics for decades. The challenge appears below half filling, where the system is a doped antiferromagnet. In this regime, the fermion…
Strongly-correlated fermion systems on a lattice have been a subject of intense focus in the field of condensed-matter physics. These systems are notoriously difficult to solve, even with state-of-the-art numerical methods, especially in…
We calculate the dynamical behaviour of a hole in various spin backgrounds in infinite dimensions, where it can be determined exactly. We consider hypercubic lattices with two different types of spin backgrounds. On one hand we study an…
Motivated by recent inelastic neutron scattering experiments on cuprates, we discuss the formation of bond order in the stripe phase. We suggest that the spin Peierls order emerges in hole-rich domain walls (DWs) formed between hole-poor…
The interplay between charge and spin dynamics is at the heart of strongly correlated materials. Inspired by recent quantum simulation experiments, we develop a conserving diagrammatic method to describe the Fermi-Hubbard model for strong…
The Shastry-Sutherland model is a two-dimensional frustrated spin model whose ground state is a spin gap state. We study this model doped with one and two holes on a 32-site lattice using exact diagonalization. When t'>0, we find that the…
Ultracold fermions in a one-dimensional, spin-dependent, optical lattice are described by a non-standard Hubbard model with next-nearest-neighbour correlated hopping. Periodic driving of the lattice allows wide tuning of the system…