Improving the spectroscopic knowledge of neutral Neodymium

TL;DR

This paper provides a detailed semi-empirical spectroscopic model of neutral neodymium, enhancing understanding of its energy levels to identify potential laser-cooling candidates among lanthanides.

Contribution

It introduces a comprehensive semi-empirical modeling of Nd energy levels using Cowan codes, filling a gap in spectroscopic data for laser-cooling applications.

Findings

Interpreted over 200 experimental energy levels

Developed a set of atomic parameters for future transition probability calculations

Enhanced spectroscopic knowledge of neodymium for laser-cooling research

Abstract

Laser cooling and trapping of lanthanides has opened the possibility to carry out new experiments with ultracold dipolar gases, for example for quantum simulation of solid state physics. To identify new suitable candidates for laser-cooling, it is important to have a precise spectroscopic knowledge of the atom under consideration. Along this direction, we present here a detailed modeling of the energy levels of neutral neodymium (Nd), an element belonging to the left part of the lanthanide row, which has not yet been considered for laser-cooling. Using the semi-empirical method implemented in the Cowan suite of codes, we are in particular able to interpret more than 200 experimental levels of the NIST database belonging to both parities. The optimal set of atomic parameters obtained after the least-square fitting step can serve to calculate radiative transition probabilities in the future.