An ytterbium quantum gas microscope with narrow-line laser cooling

Abstract

We demonstrate site-resolved imaging of individual bosonic 174Yb atoms in aHubbard-regime twodimensional optical lattice with a short lattice constant of 266 nm. To suppress the heating by probe light with the 1S0- 1P1 transition of the wavelength λ = 399 nmfor high-resolution imaging and preserve atoms at the same lattice sites during the fluorescence imaging, we simultaneously cool atoms by additionally applying narrow-line optical molasses with the 1S0 3P1 transition of the wavelength λ = 556 nm.We achieve a lowtemperature of T = 7.4(13) μK, corresponding to amean oscillationquantum number along the horizontal axes of 0.22(4) during the imaging process.Wedetect, on average, 200 fluorescence photons from a single atom within a 400 ms exposure time, and estimate a detection fidelity of 87(2)%. The realization of a quantum gas microscope with enough fidelity for Yb atoms in a Hubbard-regime optical lattice opens up the possibilities for studying various kinds of quantum many-body systems such as Bose and Fermi gases, and their mixtures, and also long-rangeinteracting systems such as Rydberg states.