The competition between antiferromagnetism and superconductivity in a doped Hubbard model with anisotropic interaction

TL;DR

This paper investigates the competition between antiferromagnetism and superconductivity in a doped Hubbard model with anisotropic interactions using quantum Monte Carlo simulations, revealing conditions under which superconductivity emerges.

Contribution

It introduces a double layer Hubbard-Heisenberg model free of the sign problem and demonstrates how tuning parameters suppress antiferromagnetism to induce superconductivity.

Findings

Superconductivity appears when antiferromagnetism is suppressed.

The model mimics transitions in unconventional superconductors.

Ground state correlations were successfully extracted.

Abstract

The competition between antiferromagnetism and superconductivity is one of the central questions in the research of strong correlated systems. In this work, we utilize a double layer model containing Hubbard interaction and interlayer Heisenberg interaction to reveal their competitions. This model is free of sign problem at certain conditions, and we perform projector quantum Monte Carlo simulations to extract the ground state correlations of magnetism and superconductivity. Our results shows that the superconductivity emerges when the antiferromagnetism is suppressed by tuning the filling or the anisotropy of the interlayer Heisenberg interaction. This model can be seen as an analogue of unconventional superconductors and may help us to understand the transition from an antiferromagnetic insulator to a superconductor.