Staggered flux and stripes in doped antiferromagnets

TL;DR

This paper investigates whether mean-field spin textures generate fictitious flux in doped antiferromagnets, analyzing uniform and striped phases to understand their energetic stability and topological properties.

Contribution

It introduces a numerical study of flux generation in striped phases of the doped $t-J$ model, linking flux to spin textures and comparing energetics of different configurations.

Findings

Phase separation is generally energetically favorable.

Fictitious flux can be generated in domain walls of striped phases.

Topological arguments relate flux to geometric spin textures.

Abstract

We have numerically investigated whether or not a mean-field theory of spin textures generate fictitious flux in the doped two dimensional $t-J$-model. First we consider the properties of uniform systems and then we extend the investigation to include models of striped phases where a fictitious flux is generated in the domain wall providing a possible source for lowering the kinetic energy of the holes. We have compared the energetics of uniform systems with stripes directed along the (10)- and (11)-directions of the lattice, finding that phase-separation generically turns out to be energetically favorable. In addition to the numerical calculations, we present topological arguments relating flux and staggered flux to geometric properties of the spin texture. The calculation is based on a projection of the electron operators of the $t-J$ model into a spin texture with spinless fermions.