Variation of the Fine-Structure Constant and Laser Cooling of Atomic Dysprosium

TL;DR

This study monitored atomic dysprosium over eight months to detect potential variations in the fine-structure constant, finding no significant change and also exploring laser cooling techniques for the atom.

Contribution

It provides the first long-term measurement constraining the variation of the fine-structure constant using dysprosium and introduces initial laser cooling results for atomic dysprosium.

Findings

No significant variation in α detected within measurement sensitivity.

Established upper bounds on the temporal variation rate of α.

Presented initial laser cooling results for dysprosium atomic beam.

Abstract

Radio-frequency electric-dipole transitions between nearly degenerate, opposite parity levels of atomic dysprosium (Dy) were monitored over an eight-month period to search for a variation in the fine-structure constant, $\alpha$. The data provide a rate of fractional temporal variation of $\alpha$ of $(-2.4\pm2.3)\times10^{-15}$ yr$^{-1}$ or a value of $(-7.8 \pm 5.9) \times 10^{-6}$ for $k_\alpha$, the variation coefficient for $\alpha$ in a changing gravitational potential. All results indicate the absence of significant variation at the present level of sensitivity. We also present initial results on laser cooling of an atomic beam of dysprosium.