Journal of Physics Conference Series

Collisions between cold molecules in a superconducting magnetic trap

Martin Pitzer, Yair Segev, Michael Karpov, N Akerman, Julia Narevicius, Edvardas Narevicius

Published Jan 1, 2020• 5 citations

Abstract

Synopsis We decelerate and trap molecular oxygen using time-dependent magnetic fields and superconducting magnets. The density-dependent, non-exponential decay in particle number provides a clear proof of molecule-molecule collisions within the trapped ensemble. The spatial distribution of molecules in the trap is found to change over time, allowing to set limits on the ratio between the elastic and inelastic collision cross sections. Our experimental scheme opens up new possibilities for studying quantum effects in chemistry as well as for evaporative cooling of molecules.

DOI: 10.1088/1742-6596/1412/12/122001

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Journal of Physics Conference Series

Collisions between cold molecules in a superconducting magnetic trap

Martin Pitzer, Yair Segev, Michael Karpov, N Akerman, Julia Narevicius, Edvardas Narevicius

Published Jan 1, 2020• 5 citations

Publisher

Abstract

DOI: 10.1088/1742-6596/1412/12/122001

Related papers

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Physical Review AAug 10, 201016 citations

{}^{17}{\mathrm{O}}_{2}

looks like a good candidate for ultracold studies, while

{}^{16}{\mathrm{O}}_{2}

is unlikely to survive evaporative cooling. Since

{}^{17}{\mathrm{O}}_{2}

is representative of a wide class of molecules that are paramagnetic in their ground state we conclude that many molecules can be successfully magnetically trapped at ultralow temperatures.

J=3/2,{M}_{J}=3/2,f

) molecules with

^{4}\mathrm{He}

atoms. Our calculations quantify the extent to which both elastic and inelastic cross sections are suppressed by external trapping fields, clarify the role of small-angle scattering in trap loss, and may benefit future experiments on collisional cooling of molecules in electromagnetic traps. The calculated cross sections for trap loss in

^{4}\mathrm{He}

+

OH collisions are consistent with recent experimental observations at low beam energies [B. C. Sawyer et al., Phys. Rev. Lett. 101, 203203 (2008)], demonstrating the importance of including the effects of nonuniform trapping fields in theoretical simulations of cold collision experiments with trapped molecules and slow atomic beams.