Anisotropic two-dimensional Heisenberg model by Schwinger-boson Gutzwiller projected method

TL;DR

This paper investigates the anisotropic two-dimensional Heisenberg model using Schwinger-boson mean-field theory combined with Gutzwiller projection, revealing persistent antiferromagnetic order even in the one-dimensional limit.

Contribution

It introduces a combined Schwinger-boson and Gutzwiller projection approach to study anisotropic 2D Heisenberg models, providing new insights into their magnetic order.

Findings

Antiferromagnetic order persists down to 1D limit.

Energy and correlations computed for large systems.

Method effectively captures anisotropic effects.

Abstract

Two-dimensional Heisenberg model with anisotropic couplings in the $x$ and $y$ directions ($J_x \neq J_y$) is considered. The model is first solved in the Schwinger-boson mean-field approximation. Then the solution is Gutzwiller projected to satisfy the local constraint that there is only one boson at each site. The energy and spin-spin correlation of the obtained wavefunction are calculated for systems with up to $20 \times 20$ sites by means of the variational Monte Carlo simulation. It is shown that the antiferromagnetic long-range order remains down to the one-dimensional limit.