Automatic calibration of arrays of superconducting qubits and couplers

High-fidelity operation of superconducting qubits requires fine-tuning numerous experimental parameters. As superconducting qubit systems scale up to large arrays, automatic calibration becomes essential, both for bringing up systems from scratch and for maintaining calibrations. These algorithms depend strongly on the qubit architecture. For example, consider arrays of qubits connected by adjustable couplers, where the coupling can be turned off to isolate qubits and turned on to facilitate fast interactions. These couplers substantially complicate automatic calibration. At the start, the coupling may inadvertently be very strong, which can disrupt qubit bringup, and we can only learn about the coupler configuration indirectly through qubit measurements. In this presentation, we describe algorithms and experiments to automatically calibrate superconducting qubits and couplers.