Measurement of the Hyperfine Quenching Rate of the Clock Transition in $^{171}$Yb

TL;DR

This paper experimentally measures the hyperfine quenching rate of a specific Yb atomic transition, crucial for optical clock precision, using fluorescence decay in solid neon, and finds results consistent with theoretical predictions.

Contribution

First experimental determination of the hyperfine quenching rate of the $^{171}$Yb clock transition using fluorescence decay in solid neon.

Findings

Hyperfine quenching rate is $(4.42\u00b1 0.35) imes 10^{-2} ext{ s}^{-1}$ for free $^{171}$Yb.

Results agree with recent ab initio calculations.

Method involves spectrally resolved fluorescence decay measurements in solid neon.

Abstract

We report the first experimental determination of the hyperfine quenching rate of the $6s^2\ ^1\!S_0\ (F=1/2) - 6s6p\ ^3\!P_0\ (F=1/2)$ transition in $^{171}$Yb with nuclear spin $I=1/2$. This rate determines the natural linewidth and the Rabi frequency of the clock transition of a Yb optical frequency standard. Our technique involves spectrally resolved fluorescence decay measurements of the lowest lying $^3\!P_{0,1}$ levels of neutral Yb atoms embedded in a solid Ne matrix. The solid Ne provides a simple way to trap a large number of atoms as well as an efficient mechanism for populating $^3\!P_0$. The decay rates in solid Ne are modified by medium effects including the index-of-refraction dependence. We find the $^3\!P_0$ hyperfine quenching rate to be $(4.42\pm0.35)\times10^{-2}\ \mathrm{s}^{-1}$ for free $^{171}$Yb, which agrees with recent ab initio calculations.