Quantum-State Controlled Penning Ionization Reactions between Ultracold Alkali and Metastable Helium Atoms
Abstract
In an ultracold, optically trapped mixture of Rb and metastable triplet He atoms we have studied trap loss for different spin-state combinations, for which interspecies Penning ionization is the main two-body loss process. We observe long trapping lifetimes for the purely quartet spin-state combination, indicating strong suppression of Penning ionization loss by at least two orders of magnitude. For the other spin-mixtures we observe short lifetimes that depend linearly on the doublet character of the entrance channel. We compare the extracted loss rate coefficient with recent predictions of multichannel quantum-defect theory for reactive collisions involving a strong exothermic loss channel and find near-universal loss for doublet scattering. Our work demonstrates control of reactive collisions by internal atomic state preparation.
Keywords
Cite
@article{arxiv.1609.01098,
title = {Quantum-State Controlled Penning Ionization Reactions between Ultracold Alkali and Metastable Helium Atoms},
author = {Adonis Silva Flores and Wim Vassen and Steven Knoop},
journal= {arXiv preprint arXiv:1609.01098},
year = {2016}
}
Comments
5 pages, 5 figures + Supplemental Materials