Amy Wakim

Formation of ultracold, highly polar X1Σ+ NaCs molecules

We present photoassociation spectroscopy of ultracold NaCs molecules formed in a dual-species magneto-optical trap. Excited-state molecules are formed in states correlating to the Na(3S1/2)+Cs(6P3/2) asymptote. We assign the most prominent observed vibrational progression to the Ω=2 long range state based on a comparison with ab initio potentials. Molecules are secondarily excited before decaying to deeply bound levels of the electronic ground X1Σ+ state where they are ionized and detected by time-of-flight mass spectroscopy.

Luminorefrigeration: vibrational cooling of NaCs

We demonstrate the use of optical pumping of kinetically ultracold NaCs to cool an initial vibrational distribution of electronic ground state molecules X(1)Σ(+)(v ≥ 4) into the vibrational ground state X(1)Σ(+)(v=0). Our approach is based on the use of simple, commercially available multimode diode lasers selected to optically pump population into X(1)Σ(+)(v=0). We investigate the impact of the cooling process on the rotational state distribution of the vibrational ground state, and observe that an initial distribution, J(initial)=0-2 is only moderately affected resulting in J(final)=0-4. This method provides an inexpensive approach to creation of vibrational ground state ultracold polar molecules.

Lumino-Refrigeration: Deep Cooling Polar Molecules by Optical Pumping

Our ability to laser cool atoms depends on the availability of a closed-cycling transition that allows many successive photons to be scattered by the atom. By comparison, molecules have a richer internal structure that is an asset and a liability. It offers new degrees of freedom for exciting experiments but precludes a simple scheme for molecular laser cooling.

Dynamics of Ultracold Polar Molecules in a Thin Wire Electrostatic Trap (TWIST)

Improvement in the lifetime of electrostatically trapped and deeply bound, polar NaCs molecules in the X1? state is achieved. Studies of optical and inter-species interactions occurring in the TWIST are presented.