Measurement of the Hyperfine Quenching Rate of the Clock Transition in 171Yb

We report the first experimental determination of the hyperfine quenching rate of the 6s(2) S-1(0)(F = 1/2) - 6s6p P-3(0)(F = 1/2) transition in Yb-171 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 P-3(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 P-3(0). The decay rates in solid Ne are modified by medium effects including the index-of-refraction dependence. We find the P-3(0) hyperfine quenching rate to be (4.42 +/- 0.35) x 10(-2) s(-1) for free Yb-171, which agrees with recent ab initio calculations.