● Measuring nonlocal order in two dimensions

Exotic quantum many-body states, such as Haldane and spin liquid phases, can exhibit remarkable features like fractional excitations and non-abelian statistics and offer new understandings of quantum entanglement in many-body quantum systems. These phases are classified by non-local correlators that can be directly measured in atomic analog quantum simulating platforms, such as optical lattices and Rydberg atom arrays. However, characterizing these phases in large systems is experimentally challenging because they are sensitive to local errors like atom loss, which suppress its signals exponentially. Additionally, protocols for systematically identifying and mitigating uncorrelated errors in analog quantum simulators are lacking. Here, we address these challenges by developing an error correction method for large-scale neutral atom quantum simulators using optical lattices. 

Reference: Physical Review X (accepted) preprint at arxiv:2305.10592v1(2023)

● Quantum gas microscope of Lithium-7 atoms

We demonstrate single-site and single-atom-resolved fluorescence imaging of a bosonic Mott insulator of 7 Li atoms in an optical lattice. The fluorescence images are obtained by implementing Raman sideband cooling on a deep two-dimensional square lattice, where we collect scattered photons with a high numerical aperture objective lens. The square lattice is created by a folded retroreflected beam configuration that can reach a 2.5 mK lattice depth from a single laser source. The lattice beam is elliptically focused to have a large area with deep potential. On average, 4000 photons are collected per atom during 1 s of Raman sideband cooling and the imaging fidelity is over 95 % in the central 80 × 80 lattice sites.

Reference: Physical Review A 99, 053604 (2019)