Progress towards imaging and cooling with the narrow-line 6S_1/2- 5D_5/2electric quadrupole transition in tweezer-trapped Cs atoms.

Narrow-line transitions of atoms have had a great impact in quantum metrology and simulation. These transitions make cooling schemes possible which rely on motional state resolution, such as attractive and repulsive Sisyphus cooling and resolved single-photon sideband cooling. These techniques are readily accessible to alkaline-earth atoms due to their intercombination lines but are generally not amenable to alkali atoms. This talk will present the experimental progress of driving the 685 nm 6S_1/2-5D_5/2 electric-quadrupole (E2) transition in Cs, which due to decay almost entirely through the 6P_3/2 state has an effective linewidth of ~100 kHz. Two units of angular momentum are transferred from a single photon to a tweezer-trapped Cs atom via spin and orbital angular momentum. We show that the E2 transition can be driven by placing the atom into the dark spot of a donut beam, and present progress towards ground state preparation via attractive Sisyphus cooling and magic polarization angle-tuned resolved sideband cooling. Finally, we show background-free single atom imaging with this transition, where the usual requirement for high scattering rates to differentiate from excitation laser scattering is relaxed due to emission at 852 nm.