# Spectroscopy of the 1001 nm transition in atomic dysprosium

## TL;DR

This paper reports precise spectroscopy of cold dysprosium atoms at 1001 nm, measuring a long excited state lifetime, polarizability ratios, and isotope shifts with high accuracy, advancing understanding of dysprosium's atomic properties.

## Contribution

The study provides the first detailed measurements of the 1001 nm transition in dysprosium, including lifetime, polarizability ratio, and isotope shifts with unprecedented precision.

## Key findings

- Excited state lifetime is at least 87.2 ms.
- Polarizability ratio at 1064 nm is 0.828(0.129).
- Isotope shifts measured with <30 kHz accuracy.

## Abstract

We report on spectroscopy of cold dysprosium atoms on the $1001\,\mathrm{nm}$ transition and present measurements of the excited state lifetime which is at least $87.2(6.7)\,\mathrm{ms}$ long. Due to the long excited state lifetime we are able to measure the ratio of the excited state polarizability to the ground state polarizability at $1064\,\mathrm{nm}$ to be $0.828(0.129)$ by parametric heating in an optical dipole trap. In addition we measure the isotope shifts of the three most abundant bosonic isotopes of dysprosium on the $1001\,\mathrm{nm}$ transition with an accuracy better than $30\,\mathrm{kHz}$.