Charge and spin orders in the t-U-V-J model: a slave-spin-1 approach

TL;DR

This paper introduces a novel slave-particle approach to study the complex charge and spin orders in the t-U-V-J model, revealing stripe phases consistent with other numerical methods.

Contribution

A new spin-1 slave-particle formalism is developed to analyze the t-U-V-J model at various dopings, capturing stripe phases not seen in previous studies.

Findings

Charge and spin stripes emerge in the phase diagram.

The method qualitatively agrees with more reliable numerical techniques.

Stripe phases are a novel prediction of this formalism.

Abstract

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 regimes of parameters where degrees of freedom compete or cooperate at similar energy and length scales. Here, we introduce a spin-1 slave-particle technique to approximately treat the t-U-V-J fermionic model at arbitrary electron dopings in an economical manner. This formalism respectively maps the original charge and spin degrees of freedom into effective pseudo-spin and pseudo-fermion sectors, which are treated using a self-consistent cluster mean-field method. We study the phase diagram of the model under various conditions and report the appearance of charge and spin stripes within this formalism. These stripes are a consequence of the cluster mean-field treatment of the pseudo-particle sectors and have not been detected in previous slave-particle studies. The results obtained agree qualitatively well with what more reliable numerical methods capture.