Fidelity Optimization of the Cross-resonance Gate on a Multi-qubit Quantum Processor*

In this work, we benchmark the performance of the cross-resonance gate in a multi-qubit setting, and evaluate gate fidelity as a function of circuit and control parameters, such as qubit detuning, effective coupling rate, and control pulse shape. We use numerical techniques to efficiently optimize gate parameter configurations. Lastly, we monitor the error syndromes of calibrated gates to investigate their sensitivity to environmental drift. This work outlines systematic calibration and operation of cross-resonance gates with model-guided optimization for general algorithmic utilization in near-term quantum computers.