Generation of neutral atomic beams utilizing photodetachment by high power diode laser stacks

TL;DR

This paper demonstrates a practical method for producing neutral atomic beams by photodetaching negative ions using high power diode laser stacks, achieving notable efficiencies with a simple, stable setup.

Contribution

The study introduces a straightforward, stable, and efficient diode laser-based system for photodetachment of negative ions to generate neutral atomic beams without complex enhancements.

Findings

Achieved 7.4% photodetachment efficiency for H$^-$ at 10 keV

Achieved 3.7% efficiency for C$^-$ at 28 keV

System operates at high power levels with minimal maintenance

Abstract

We demonstrate the use of high power diode laser stacks to photodetach fast hydrogen and carbon anions and produce ground term neutral atomic beams. We achieve photodetachment efficiencies of $\sim$7.4\% for H$^-$ at a beam energy of 10\,keV and $\sim$3.7\% for C$^-$ at 28\,keV. The diode laser systems used here operate at 975\,nm and 808\,nm, respectively, and provide high continuous power levels of up to 2\,kW, without the need of additional enhancements like optical cavities. The alignment of the beams is straightforward and operation at constant power levels is very stable, while maintenance is minimal. We present a dedicated photodetachment setup that is suitable to efficiently neutralize the majority of stable negative ions in the periodic table.