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arXiv · 1909.01694

Suppression of Penning ionization by orbital angular momentum conservation

Katrin Dulitz·Tobias Sixt·Jiwen Guan·Jonas Grzesiak·Markus Debatin·Frank Stienkemeier
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Abstract

The efficient suppression of Penning-ionizing collisions is a stringent requirement to achieve quantum degeneracy in metastable rare gases. Thus far, such loss processes have been avoided by electron-spin polarizing the collision partners. Here, we report on the efficient suppression of Penning ionization in collisions between metastable He and laser-excited Li atoms. The results illustrate that not only the electron spin, but also $\Lambda$ - the projection of the total molecular orbital angular momentum along the internuclear axis - is conserved during the ionization process. Our findings suggest that $\Lambda$ conservation can be used as a more general means of reaction control, for example, to improve schemes for the simultaneous laser cooling and trapping of metastable He and alkali atoms.

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Katrin Dulitz, Tobias Sixt, Jiwen Guan, Jonas Grzesiak, Markus Debatin, Frank Stienkemeier. 2019-09-04. Suppression of Penning ionization by orbital angular momentum conservation. https://doi.org/10.1103/physreva.102.022818

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