Measurement of the Isotopic Shift of the S1/2–D5/2 Clock Transition in Monoisotopic Clouds of Strontium Ions

The isotopic shifts of the 5s 2S1/2–5p 2P1/2 cooling transition, the 5p 2P1/2–4d 2D3/2 pumping transition, and the 5s 2S1/2–4d 2D5/2 electroquadrupole transition are measured in monoisotopic clouds of strontium ions: 88Sr+, 86Sr+, and 84Sr+. To the best of our knowledge, the isotopic shift of the clock transition at 674 nm in 84Sr+ is measured for the first time and is found to be 1186.7(7.2) MHz. The obtained experimental data is used to construct a King diagram, which allows the field (F) and mass (K) shift constants to be estimated for the transition at a wavelength of 674 nm. The obtained results can be used to test atomic structure calculations, sympathetic cooling, and quantum algorithms.