Dissipative Preparation of Antiferromagnetic Order in the Fermi-Hubbard Model

TL;DR

This paper proposes a dissipative quantum engineering method to efficiently prepare antiferromagnetic order in the Fermi-Hubbard model using ultracold fermions, overcoming current temperature limitations in experiments.

Contribution

It introduces a novel dissipative approach to generate antiferromagnetic order, compatible with existing ultracold atom experiments, and employs advanced simulation techniques to analyze the process.

Findings

Antiferromagnetic order can be prepared as a dark state via engineered dissipation.

The method is compatible with current ultracold atom experimental setups.

Simulations show effective development of antiferromagnetic order under dissipative dynamics.

Abstract

The Fermi-Hubbard model is one of the key models of condensed matter physics, which holds a potential for explaining the mystery of high-temperature superconductivity. Recent progress in ultracold atoms in optical lattices has paved the way to studying the model's phase diagram using the tools of quantum simulation, which emerged as a promising alternative to the numerical calculations plagued by the infamous sign problem. However, the temperatures achieved using elaborate laser cooling protocols so far have been too high to show the appearance of antiferromagnetic and superconducting quantum phases directly. In this work, we demonstrate that using the machinery of dissipative quantum state engineering, one can efficiently prepare antiferromagnetic order in present-day experiments with ultracold fermions. The core of the approach is to add incoherent laser scattering in such a way that the antiferromagnetic state emerges as the dark state of the driven-dissipative dynamics. In order to elucidate the development of the antiferromagnetic order we employ two complementary techniques: Monte Carlo wave function simulations for small systems and a recently proposed variational method for open quantum systems, operating in the thermodynamic limit. The controlled dissipation channels described in this work are straightforward to add to already existing experimental setups.