Quantum Gas Microscope of Bosonic Atoms with Tunable Interaction

In this presentation, we report a quantum gas microscope of Lithium-7 atoms in a two-dimensional (2D) square optical lattice. Individual atoms in each lattice site are imaged by Raman sideband cooling in a hybrid potential of the 2D lattice and a single tightly focused optical sheet potential. With a high numerical aperture (NA=0.65) objective, we achieve a point spread function of 600 nm (full width half maximum), which is small enough to resolve the lattice spacing (752 nm). About 3000 photons were collected during 1 s of exposure time with a detection fidelity of 98%. Moreover, using the magnetic Feshbach resonance, we are able to obtain a large size of unity filling Mott insulator containing 1000 atoms. Imaging the atoms in the deep lattice potential with Gray molasses will be also discussed.