Optical Excitation and Trapping of $^{81}$Kr

TL;DR

This paper demonstrates the optical excitation, trapping, and detection of the rare isotope $^{81}$Kr using a novel all-optical method, significantly improving the loading rate and enabling advanced applications in earth sciences.

Contribution

It introduces an all-optical technique for $^{81}$Kr detection, achieving high loading rates and overcoming previous limitations in radiokrypton dating.

Findings

Achieved a $^{81}$Kr loading rate of 1800 atoms/hour.

Optimized photon transport in krypton gas enhances resonance.

Method enables new applications in dating polar ice cores.

Abstract

We have realized optical excitation, trapping and detection of the radioisotope $^{81}$Kr with an isotopic abundance of 0.9 ppt. The 124 nm light needed for the production of metastable atoms is generated by a resonant discharge lamp. Photon transport through the optically thick krypton gas inside the lamp is simulated and optimized to enhance both brightness and resonance. We achieve a state-of-the-art $^{81}$Kr loading rate of 1800 atoms/h, which can be further scaled up by adding more lamps. The all-optical approach overcomes the limitations on precision and sample size of radiokrypton dating, enabling new applications in the earth sciences, particularly for dating of polar ice cores.