Towards Raman sideband cooling of a single atom in a microscopic optical trap

Neutral atoms in microscopic optical traps (“optical tweezers”) are promising as a platform for quantum computation and simulation. Our group has been focused on utilizing fermionic atoms to this end, and in particular, on harnessing the fermionic statistics and exchange interaction to perform robust quantum gates. A crucial step in the route to low entropy atomic arrays is to prepare a single atom in the vibrational ground state of the tweezer. One way to accomplish this is by cooling inside the micro-trap.

In this seminar, I present our progress towards Raman sideband cooling of ⁴⁰K atoms in a micro-trap. The technique relies on a repeated cycle of stimulated Raman transition followed by optical pumping and spontaneous emission. The Raman transition lowers the vibrational energy by a single quantum, while optical pumping in the Lamb-Dicke regime allows energy dissipation without further change of the vibrational state. I will discuss the use of this technique in both preparation and detection. I will then describe the implementation of the scheme in our setup and explain the inherent challenges. Finally, I will present preliminary results and discuss the next steps to achieve our goal.