Single‐ion spectroscopy system for the 2S1/2(F = 0) − 2D3/2(F = 2) transition in 171Yb

We report on our system and scheme for single‐ion spectroscopy of the 2S1/2(F=0)−2D3/2(F=2) clock transition in 171Yb+. Spectroscopy of the clock transition requires decoupling of the 2D3/2(F=2) state from the laser cooling cycle. We investigate this decoupling of the 2D3/2(F=2) state by using independent light sources for driving of all the transitions between the hyperfine structures contained in the cooling and repumping transitions. We observe the carrier spectrum of the mF=0−mF′=0 magnetic‐insensitive transition with a spectral width of 380 Hz. Key Points A system for spectroscopy of the clock transition at 435 nm in a single ytterbium ion of isotope 171 is developed Laser cooling, state preparation, and state detection techniques are developed The observed spectrum has a full width at half maximum of 380 Hz, which indicates the need for improvement of the clock‐laser linewidth