Alkali ion-to-neutral atom converter for the magneto-optical trap of a radioactive isotope

TL;DR

This paper presents a novel neutralizer device using yttrium and platinum to efficiently convert radioactive ions into neutral atoms for magneto-optical trapping, demonstrated with rubidium and francium.

Contribution

The development of a unique yttrium-based neutralizer device that achieves high-efficiency ion-to-neutral atom conversion for radioactive isotopes in magneto-optical traps.

Findings

Successfully neutralized rubidium atoms with $10^6$ atoms trapped.

Demonstrated neutralization of francium atoms.

Achieved small angular divergence in the neutral atomic beam.

Abstract

We have developed a unique neutralizer device that uses an yttrium target surrounded by a platinum wall to magneto-optically trap radioactive atoms. In general, the radioactive nucleus produced in a nuclear reaction is extracted and transported in ion form. For the magneto-optical trap, thermal neutralization must occur on the surface of a metal with a small work function. The converter can produce a neutral atomic beam with small angular divergence that, given the recycling of atoms and ions, converts ions into neutral atoms with remarkable efficiency. We demonstrated the ion neutralization process using stable rubidium and confirmed $10^6$ neutralized atoms in the magneto-optical trap. Additionally, the experiment using francium demonstrated the obtaining of neutralized francium atoms.