Tailored Optical Clock Transition in 40Ca+

We engineer an artificial optical clock transition in 40Ca+ with a continuous dynamical decoupling scheme. It suppresses inhomogeneous tensor shifts as well as the linear Zeeman shift, making it suitable for multi-ion operation. Coherence times approaching the natural lifetime limit ensure low statistical uncertainties on the optical transition. We continuously apply the dressing fields, making the tailored transition robust against magnetic field fluctuations during the entire clock probe time.