Magnetic Trapping and Coherent Control of Laser-Cooled Molecules.

  title={Magnetic Trapping and Coherent Control of Laser-Cooled Molecules.},
  author={H. J. Williams and Luke Caldwell and N J Fitch and S. Truppe and Jonas Rodewald and E. A. Hinds and B E Sauer and M R Tarbutt},
  journal={Physical review letters},
  volume={120 16},
We demonstrate coherent microwave control of the rotational, hyperfine, and Zeeman states of ultracold CaF molecules, and the magnetic trapping of these molecules in a single, selectable quantum state. We trap about 5×10^{3} molecules for almost 2 s at a temperature of 70(8)  μK and a density of 1.2×10^{5}  cm^{-3}. We measure the state-specific loss rate due to collisions with background helium. 

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