Regensburg 2022 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
QI: Fachverband Quanteninformation
QI 13: Implementations: Superconducting Qubits
QI 13.5: Vortrag
Freitag, 9. September 2022, 10:45–11:00, H8
Tunable-coupler mediated controlled-controlled-phase gate with superconducting qubits — •Niklas J Glaser1,2, Federico Roy1,3, and Stefan Filipp1,2,4 — 1Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, 85748 Garching, Germany — 2Physik-Department, Technische Universität München, 85748 Garching, Germany — 3Theoretical Physics, Saarland University, 66123 Saarbrücken, Germany — 4Munich Center for Quantum Science and Technology (MCQST), 80799 München, Germany
Applications for noisy intermediate scale quantum computing devices rely on the efficient entanglement of many qubits to reach a potential quantum advantage. Although entanglement is typically generated using two-qubit gates, direct control of strong multi-qubit interactions can improve the efficiency of the process. We investigate a system of three superconducting transmon-type qubits coupled via a single flux-tunable coupler. Tuning the frequency of the coupler by adiabatic flux pulses enables us to control the conditional energy shifts between the qubits and directly realize multi-qubit interactions. To accurately adjust the resulting controlled relative phases, we describe a gate protocol involving refocusing pulses and adjustable interaction times. This enables the implementation of the full family of pairwise controlled-phase (CPHASE) and controlled-controlled-phase (CCPHASE) gates. Numerical simulations result in fidelities around 99% and gate times below 300 ns using currently achievable system parameters and decoherence rates.