FPGA-based optimal control for two-qubit gates

Improved controls for high-coherence superconducting qubits will enable high-fidelity multi-qubit gates. Superconducting qubits made of tantalum were recently found to have lifetimes and coherence times exceeding 0.3 milliseconds. Implementing Field-Programmable Gate Array (FPGA)-based qubit control enables real-time feedback which informs qubit state preparation and allows for careful study of quantum trajectories and decoherence. Implementing classical signal-processing calculations digitally on the FPGA further enhances the quality of control. Here we present the results of these new controls applied in an optimal control scheme for a two-qubit gate.