We demonstrate atom-resolved imaging of fermionic lithium-6 in a sparsely-filled optical lattice. Lithium, with its fast dynamics and tunable interactions, is an ideal species to study quantum many-body
physics with ultracold atoms under a quantum gas microscope. Obtaining a site-resolved fluorescence image in such a microscope requires scattering many thousands of photons off of each atom while laser-cooling the atoms. Lithium's large recoil energy and its unresolved excited state hyperfine structure make sub-Doppler laser cooling challenging. To address these issues, we developed an imaging technique based on Raman sideband cooling. We load atoms into a single layer of a three-dimensional optical lattice with 566 nm lattice spacing, 10 micron below a super-polished substrate that forms the last element of an imaging system with 0.85 numerical aperture. The lattice is then ramped to a depth of approximately 3 mK leading to trap frequencies ~1 MHz. In this deep lattice we apply an alternating sequence of imaging pulses and Raman sideband cooling to image the atoms while keeping them pinned to their lattice sites.