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arXiv · 1111.5829

Magnetic-field dependent trap loss of ultracold metastable helium

J. S. Borbely·R. van Rooij·S. Knoop·W. Vassen
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Abstract

We have experimentally studied the magnetic-field dependence of the decay of a Bose-Einstein condensate of metastable 4He atoms confined in an optical dipole trap, for atoms in the m=+1 and m=-1 magnetic substates, and up to 450 G. Our measurements confirm long-standing calculations of the two-body loss rate coefficient that show an increase above 50 G. We demonstrate that for m=-1 atoms, decay is due to three-body recombination only, with a three-body loss rate coefficient of 6.5(0.4)(0.6)10^(-27)cm^6s^(-1), which is interesting in the context of universal few-body theory. We have also searched for a recently-predicted d-wave Feshbach resonance, but did not observe it.

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J. S. Borbely, R. van Rooij, S. Knoop, W. Vassen. 2011-11-24. Magnetic-field dependent trap loss of ultracold metastable helium. https://doi.org/10.1103/physreva.85.022706

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