Magnetic Domains and Stripes in the Spin-Fermion Model for Cuprates

TL;DR

This study uses Monte Carlo simulations of the Spin-Fermion model to reveal antiferromagnetic spin domains and charge stripes in cuprates, aligning with experimental observations and showing their impact on electronic properties.

Contribution

It demonstrates the spontaneous formation of charge stripes and magnetic domains in the Spin-Fermion model without external stabilization, matching experimental incommensurate peaks.

Findings

Charge stripes are partially filled with ~1/2 hole per site.

Stripe orientations are along x or y axes with large energy barriers.

Charge fluctuations induce a pseudogap in the density of states.

Abstract

Monte Carlo simulations applied to the Spin-Fermion model for cuprates show the existence of antiferromagnetic spin domains and charge stripes upon doping. The stripes are partially filled, with a filling of approximately 1/2 hole per site, and they separate spin domains with a $\pi$ phase shift among them. The stripes observed run either along the x or y axes and they are separated by a large energy barrier. No special boundary conditions or external fields are needed to stabilize these structures at low temperatures. When magnetic incommensurate peaks are observed at momentum $\pi(1,1-\delta)$ and symmetrical points, charge incommensurate peaks appear at $(0,2 \delta)$ and symmetrical points, as experimentally observed. The strong charge fluctuations responsible for the formation of the stripes also induce a pseudogap in the density of states.