Spectroscopy of a narrow-line laser cooling transition in atomic dysprosium

TL;DR

This paper investigates a narrow-line 741-nm transition in dysprosium for laser cooling, providing experimental data on isotope shifts, hyperfine constants, and decay rates to enable ultracold Dy preparation.

Contribution

The study identifies and characterizes a promising narrow-line transition in dysprosium for improved laser cooling and trapping techniques.

Findings

Measured isotope shifts and hyperfine constants for the 741-nm transition.

Determined decay rate and linewidth of the 421-nm transition.

Summarized laser cooling characteristics of multiple transitions in Dy.

Abstract

The laser cooling and trapping of ultracold neutral dysprosium has been recently demonstrated using the broad, open 421-nm cycling transition. Narrow-line magneto-optical trapping of Dy on longer wavelength transitions would enable the preparation of ultracold Dy samples suitable for loading optical dipole traps and subsequent evaporative cooling. We have identified the closed 741-nm cycling transition as a candidate for the narrow-line cooling of Dy. We present experimental data on the isotope shifts, the hyperfine constants A and B, and the decay rate of the 741-nm transition. In addition, we report a measurement of the 421-nm transition's linewidth, which agrees with previous measurements. We summarize the laser cooling characteristics of these transitions as well as other narrow cycling transitions that may prove useful for cooling Dy.