Fast Reliable Automatic Parallel Calibration of High Fidelity CZ Gates on Large Superconducting Quantum Processing Units

As superconducting Quantum Processing Units (QPU) grow larger, automated and reliable calibration of high-fidelity two-qubit remains one of the main challenges. Here, we demonstrate our two-qubit gate calibration strategy that parallelizes across all the qubits and leverages fast reset to speed-up the calibration. To increase the accuracy of the calibration, we leverage techniques such as error-amplification and refocusing of the conditional phase. The calibration is designed to be fully automatic and is executed in a specific way, making the calibration duration independent of the size of the QPU. We demonstrate a two-qubit gate calibration procedure that executes in less than 10 minutes on a large quantum processor and has been shown to result in CZ-gate fidelities above 99.9%.