Free space single-site-resolved imaging in an erbium quantum gas microscope

We demonstrate single-site-resolved imaging at greater than 99.5% fidelity using shorter than 10 microsecond resonant beam pulses in our erbium quantum gas microscope. Whereas conventional quantum gas microscope experiments image the atoms in tightly spaced lattices and must collect thousands of photons per atom, our experiment transfers the atoms into variable spacing accordion lattices to enable high fidelity imaging using as few as 20 detected photons. The rapid imaging makes it possible to turn trapping lattices off, opening the door to double-occupancy readout, phase coherence readout, and multi-spin-state readout. The setup is also technically simple without the complexity of cooling or pinning lattices. The imaging method presented here, along with dipolar interactions between erbium atoms, paves the way to single-site-resolved studies of exotic quantum phases generated by Hubbard models extended with nearest-neighbor interactions.