Spin and Charge Resolved Quantum Gas Microscopy of Antiferromagnetic Order in Hubbard Chains

TL;DR

This paper demonstrates the direct detection of antiferromagnetic correlations in ultracold fermionic Hubbard chains using quantum gas microscopy, enabling detailed studies of magnetic order and doping effects in strongly correlated systems.

Contribution

It presents the first single-site resolved detection of antiferromagnetic correlations extending beyond nearest neighbors in Hubbard chains, with simultaneous spin and density measurements.

Findings

Antiferromagnetic correlations observed up to three sites.

Detection achieved at entropy levels below ln(2).

Simultaneous spin and density imaging enables new studies.

Abstract

The repulsive Hubbard Hamiltonian is one of the foundational models describing strongly correlated electrons and is believed to capture essential aspects of high temperature superconductivity. Ultracold fermions in optical lattices allow for the simulation of the Hubbard Hamiltonian with a unique control over kinetic energy, interactions and doping. A great challenge is to reach the required low entropy and to observe antiferromagnetic spin correlations beyond nearest neighbors, for which quantum gas microscopes are ideal. Here we report on the direct, single-site resolved detection of antiferromagnetic correlations extending up to three sites in spin-$1/2$ Hubbard chains, which requires an entropy well below $s^*=\ln(2)$. Finally, the simultaneous detection of spin and density opens the route towards the study of the interplay between magnetic ordering and doping in various dimensions.