Adaptable platform for trapped cold electrons, hydrogen and lithium anions and cations

TL;DR

This paper presents a versatile laboratory system for generating and trapping cold electrons, hydrogen, and lithium ions and anions, with applications in space chemistry, fundamental physics, and fusion research.

Contribution

The authors develop an adaptable platform using laser ablation and a Penning trap to produce and trap cold charged particles, including novel methods for guiding and neutralizing anions.

Findings

Achieved cold electron, hydrogen, and lithium ion/anion trapping at 0-25 meV energies.

Demonstrated guiding and neutralization of anions with near-threshold photodetachment.

Potential for scalable production applicable to various isotopes like deuterium and tritium.

Abstract

Cold cations, electrons and anions are ubiquitous in space, participate in star formation chemistry and are relevant to studies on the origin of molecular biology homochirality. We report on a system to generate and trap these species in the laboratory. Laser ablation of a solid target (LiH) facing a sublimating Ne matrix generates cold electrons, anions, and cations. Axial energy distributions (of e$^-$, H$^\pm$ and Li$^\pm$) peaked at 0-25 meV are obtained in a Penning trap at 90 mT and 0.5 eV barrier. Anions can be guided and neutralized with low recoil energy by near-threshold photodetachment. An immediate prospect for this H$^-$ source is to load hydrogen atoms into the ALPHA antihydrogen trap at CERN towards direct spectroscopic comparison of both conjugated species beyond 13 significant figures. The production is potentially scalable and adaptable to different species including deuterium and tritium, relevant for neutrino mass and fusion research.