A Fermi-Hubbard Optical Tweezer Array

TL;DR

This study demonstrates the use of lithium-6 atoms in an optical tweezer array to realize a Fermi-Hubbard model, observe Mott insulators with antiferromagnetic correlations, and explore tunneling dynamics in a highly controllable platform.

Contribution

It introduces a flexible optical tweezer platform for simulating Fermi-Hubbard physics with single-site resolution and low entropy, advancing quantum simulation capabilities.

Findings

Achieved single-site detection of lithium-6 atoms.

Observed Mott insulators with strong antiferromagnetic correlations.

Established low entropy bounds comparable to optical lattice systems.

Abstract

We use lithium-6 atoms in an optical tweezer array to realize an eight-site Fermi-Hubbard chain near half filling. We achieve single site detection by combining the tweezer array with a quantum gas microscope. By reducing disorder in the energy offsets to less than the tunneling energy, we observe Mott insulators with strong antiferromagnetic correlations. The measured spin correlations allow us to put an upper bound on the entropy of 0.26(4)$k_\mathrm{B}$ per atom, comparable to the lowest entropies achieved with optical lattices. Additionally, we establish the flexibility of the tweezer platform by initializing atoms on one tweezer and observing tunneling dynamics across the array for different 1D geometries.