Spectroscopy of the ${}^2{S}_{1/2}\to {}^2{P}_{3/2}$ transition in Yb II: Isotope shifts, hyperfine splitting and branching ratios

Abstract

We report on spectroscopic results on the ${}^2{S}_{1/2}\to {}^2{P}_{3/2}$ transition in single trapped Yb${}^{+}$ ions. We measure the isotope shifts for all stable Yb${}^{+}$ isotopes except ${}^{173}$Yb${}^{+}$, as well as the hyperfine splitting of the ${}^2{P}_{3/2}$ state in ${}^{171}$Yb${}^{+}$. Our results are in agreement with previous measurements but are a factor of 5-9 more precise. For the hyperfine constant $A\left({}^2{P}_{3/2}\right)=875.4(10)$ MHz our results also agree with previous measurements but deviate significantly from theoretical predictions. We present experimental results on the branching ratios for the decay of the ${}^2{P}_{3/2}$ state. We find branching fractions for the decay to the ${}^2{D}_{3/2}$ state and ${}^2{D}_{5/2}$ state of 0.17(1)% and 1.08(5)%, respectively, in rough agreement with theoretical predictions. Furthermore, we measured the isotope shifts of the ${}^2{F}_{7/2}\to {}^{1}D{\left[5/2\right]}_{5/2}$ transition and determine the hyperfine structure constant for the ${}^{1}D{\left[5/2\right]}_{5/2}$ state in ${}^{171}$Yb${}^{+}$ to be $A\left({}^{1}D{\left[5/2\right]}_{5/2}\right)=-107(6)$ MHz.

6 pages, 4 figures