Spectroscopy of a narrow-line optical pumping transition in dysprosium

TL;DR

This paper reports precise measurements of hyperfine coefficients, isotope shifts, and excited state lifetime of a narrow optical transition in dysprosium, demonstrating its suitability for optical pumping and cooling applications.

Contribution

It provides new hyperfine and isotope shift data, along with lifetime measurements, establishing the transition's potential for optical manipulation in dysprosium.

Findings

Updated isotope shift value with high precision

Measured excited state lifetime of 1.68 microseconds

Confirmed transition suitability for optical pumping and cooling

Abstract

We present measurements of the hyperfine coefficients and isotope shifts of the Dy I $683.731 $nm transition, using saturated absorption spectroscopy on an atomic beam. A King Plot is drawn resulting in an updated value for the specific mass shift $\delta \nu_\mathrm{684,sms}^\mathrm{164-162}=-534 \pm 17 MHz$. Using fluorescence spectroscopy we measure the excited state lifetime $\tau_{684}=1.68(5) \mu$s, yielding a linewidth of $\gamma_\mathrm{684} = 95 \pm 3 kHz$. We give an upper limit to the branching ratio between the two decay channels from the excited state showing that this transition is useable for optical pumping into a dark state and demagnetization cooling.