Columbia University and Massachusetts Institute of Technology
Quantum Control of Ultracold Dipolar Molecules
Ultracold molecules open up new routes for precision measurements, quantum information processing and many-body quantum physics. In particular, dipolar molecules with long-range interactions promise the creation of novel states of matter, such as topological superfluids and quantum crystals. Dipolar molecules can be efficiently assembled from ultracold atoms. Using this approach we created the first near-degenerate gases of strongly dipolar sodium- potassium (NaK) molecules . At temperatures as low as few hundred nanokelvin, we prepare spin-polarized molecular ensembles, in which each molecule occupies the rovibrational and hyperfine ground state.
I will discuss our advances on coherent quantum control in ultracold NaK molecules. Starting from the absolute ground state, we demonstrate coherent microwave coupling into higher rotational and hyperfine states . Furthermore, we create superpositions between the lowest hyperfine states of NaK and observe coherence times on the scale of one second, enabling precision Ramsey spectroscopy with Hertz-level resolution . These results suggest new possibilities for precision metrology and quantum information. I will conclude with an outlook on future prospects of molecular quantum gases.
 PRL 114, 205302 (2015)
 PRL 116, 225306 (2016)
 Science 357, 372-375 (2016)