While high fidelity two qubit gates have been achieved on superconducting circuit platforms in recent years, two qubit gate fidelity remains a limiting factor for algorithm performance in the NISQ era. All microwave gates implemented on fully static architectures are simple to implement and allow for high coherence qubits, but this comes at the expense of always-on couplings and slower gate times. Fully tunable architectures, on the other hand, trade minimal residual coupling and fast entangling operations for increased complexity and sensitivity to flux noise. Parametric entangling gates, which use fast flux modulation to induce resonant interactions in a rotating frame, offer a middle ground between these two approaches to high fidelity two qubit gates. By restricting tunability to a coupling element, qubit sensitivity to flux noise can be significantly reduced and high coherence maintained. Furthermore, the resonant nature of the parametric interactions allow for fast entangling gates with minimal residual coupling. At AQT, we are working towards implementing parametric entangling gates on a 10 qubit quantum processor and investigating how error sources can be mitigated to achieve gate fidelities beyond the current state-of-the-art.
