Narrow linewidth cooling of $^{6}$Li

We present progress toward the realization of narrow linewidth laser cooling on the $2S_{1/2}\rightarrow 3P_{3/2}$ transition of $^{6}$Li at 323 nm. Laser cooling on the D2 transition of $^{6}$Li at 671 nm is limited to 140 $\mu$K due to the 5.9 MHz transition linewidth. The 323 nm UV transition has a linewidth of 150 kHz, reducing the Doppler limit of laser cooling to 20 $\mu$K, still above but comparable to the recoil limit of 15 $\mu$K. We expect that implementing a stage of UV laser cooling after our 671 nm magneto-optical trap will enhance the phase-space density of the gas by a factor of 20. This will allow efficient loading to a moderately deep (700 $\mu$K) optical trap/lattice directly after laser cooling without the need of an additional deeper optical trap between the MOT and lattice stages, in contrast with other all-optical $^{6}$Li experiments.