Optimized Gutzwiller Projected States for Doped Antiferromagnets in Fermi-Hubbard Simulators

TL;DR

This paper uses machine learning to optimize resonating valence bond states based on experimental Fermi-Hubbard data, providing insights into strongly correlated systems and potential quantum spin liquid states.

Contribution

It introduces a method to optimize RVB states with experimental data, revealing their ability to capture correlations and offering a new approach for analyzing quantum many-body systems.

Findings

RVB states accurately reproduce experimental correlations

Doping dependence of parameters offers physical insights

Finite temperature data well modeled by RVB states

Abstract

In quantum many-body physics, one aims to understand emergent phenomena and effects of strong interactions, ideally by developing a simple theoretical picture. Recently, progress in quantum simulators has enabled the measurement of site resolved snapshots of Fermi-Hubbard systems at finite doping on square as well as triangular lattice geometries. These experimental advances pose the quest for theorists to analyze the ensuing data in order to gain insights into these prototypical, strongly correlated many-body systems. Here we employ machine learning techniques to optimize the mean-field parameters of a resonating valence bond (RVB) state through comparison with experimental data, thus determining a possible underlying simple model that is physically motivated and fully interpretable. We find that the resulting RVB states are capable of capturing two- as well as three-point correlations measured in experiments, even when they are not specifically used in the optimization. The analysis of the mean-field parameters and their doping dependence can be used to obtain physical insights and shed light on the nature of possible underlying quantum spin liquid states. Our results show that finite temperature data from Fermi-Hubbard quantum simulators can be well captured by RVB states. This work paves the way for a new, systematic analysis of data from numerical as well as quantum simulation of strongly correlated quantum many-body systems.