Robust laser frequency drift tracking and data sharing platform to perform qubit calibration for an ion trap quantum computer

One of the fundamental requirements for using optical transitions as qubits is an accurate control of the phase of the electric field of the laser field driving the qubit transition. For this it is necessary to calibrate the laser frequency accurately. The calibration can be achieved by simple spectroscopy scan of the optical transition. Alternatively, one can use Ramsey spectroscopy achieving a higher signal-to-noise ratio in a given time. However, if the laser frequency jumps significantly with respect to the atomic transition, one may switch by one Ramsey fringe. Here we implement a laser frequency drift tracker for the Ca⁺ quadrupole transition at 729 nm based on the Ramsey method. An algorithm adjusts automatically the Ramsey wait time to stay in tracking range while maintaining the accuracy. In addition, we develop a platform such that different ion trap experiments can share and use tracking results from other ion trap experiments.