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A Large Atom Number Metastable Helium Bose-Einstein Condensate

A. S. Tychkov·T. Jeltes·J. M. McNamara·P. J. J. Tol·N. Herschbach·W. Hogervorst·W. Vassen
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Abstract

We have produced a Bose-Einstein condensate of metastable helium (4He*) containing over 1.5x10^7 atoms, which is a factor of 25 higher than previously achieved. The improved starting conditions for evaporative cooling are obtained by applying one-dimensional Doppler cooling inside a magnetic trap. The same technique is successfully used to cool the spin-polarized fermionic isotope (3He*), for which thermalizing collisions are highly suppressed. Our detection techniques include absorption imaging, time-of-flight measurements on a microchannel plate detector and ion counting to monitor the formation and decay of the condensate.

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A. S. Tychkov, T. Jeltes, J. M. McNamara, P. J. J. Tol, N. Herschbach, W. Hogervorst, W. Vassen. 2005-11-30. A Large Atom Number Metastable Helium Bose-Einstein Condensate. https://doi.org/10.1103/physreva.73.031603

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