Engineering microwave-activated interactions for two-qubit gates and coherent-error suppression

Improving the extensibility of circuit-QED architectures is a necessary step towards developing functional large-scale quantum processors. In this context, the choice of two-qubit coupling and gate scheme is important, as it can place stringent design constraints at a larger scale. Tunable-qubit architectures offer some flexibility for mitigating frequency crowding and might have an edge in this respect. However, tunability often comes at the price of increased decoherence. In this talk, we introduce a transmon-qubit-based architecture that leverages always-on microwave drives to enhance or suppress multiqubit interactions. In the appropriate frame, the drive parameters appear as tunable knobs that are useful to enact two-qubit gates or idle with high-fidelity. We discuss ways to leverage such tunability alongside operating-regime tradeoffs that account for drive-induced decoherence.