Single ion spectroscopy of four metastable state clear-out transitions in Yb II: isotope shifts and hyperfine structure

We present spectroscopic data for four metastable state clear-out transitions between 399 nm and 412 nm for all even long-lived isotopes of Yb⁺ as well as their hyperfine structure in ¹⁷¹Yb⁺. The strong ² D3/2 → ¹[1/2]1/2 transition at 412 nm represents an attractive alternative for the standard 935 nm repumper used in cooling and trapping experiments, while the transition to the ³[3/2]3/2 state at 411 nm clears out the ²F7/2 state, for which typically 638 nm or 760 nm are used. These two alternative transitions simplify the experimental setup by removing the need for infrared optics to cool and manipulate Yb⁺ and may be of particular interest when considering integrated photonics solutions. We also present data for the transitions ²D3/2 → ³[1/2]3/2 at 399 nm, and ²D3/2 → ¹[5/2]5/2 at 410 nm including decay branching ratios of the excited states.