The magnetism of the t-t' Hubbard model

TL;DR

This paper investigates the magnetic behaviors of the two-dimensional t-t' Hubbard model, revealing complex magnetic phases and textures influenced by the ratio t'/t, using an unrestricted Hartree-Fock approach.

Contribution

It provides a detailed analysis of magnetic phase transitions and inhomogeneous textures in the t-t' Hubbard model, highlighting the effects of varying t'/t ratios.

Findings

Rich magnetic phenomena at large t'/t ratios

Transition between antiferromagnetic and ferromagnetic phases

Presence of inhomogeneous magnetic textures

Abstract

The magnetic properties of the t-t' Hubbard Model in the two dimensional square lattice are studied within an unrestricted Hartree-Fock approximation in real space. The interplay between antiferromagnetism, ferromagnetism, phase separation and inhomogeneous magnetic textures is studied. It is shown that, at sufficiently large values of t'/t, a rich fenomenology is to be expected between the antiferromagnetic phase at half filling and the ferromagnetic phase a lower fillings.