Print Email Facebook Twitter Fast, High-Fidelity Conditional-Phase Gate Exploiting Leakage Interference in Weakly Anharmonic Superconducting Qubits Title Fast, High-Fidelity Conditional-Phase Gate Exploiting Leakage Interference in Weakly Anharmonic Superconducting Qubits Author Rol, M.A. Battistel, F. Malinowski, F.K. Bultink, C.C. Tarasinski, B.M. Vollmer, R. Haider, S.N. Muthusubramanian, N. Bruno, A. Terhal, B.M. Dicarlo, L. Publication year 2019 Abstract Conditional-phase (cz) gates in transmons can be realized by flux pulsing computational states towards resonance with noncomputational ones. We present a 40 ns cz gate based on a bipolar flux pulse suppressing leakage (0.1%) by interference and approaching the speed limit set by exchange coupling. This pulse harnesses a built-in echo to enhance fidelity (99.1%) and is robust to long-timescale distortion in the flux-control line, ensuring repeatability. Numerical simulations matching experiment show that fidelity is limited by high-frequency dephasing and leakage by short-timescale distortion. © 2019 American Physical Society. Subject Atomic physicsPhysicsFlux controlHigh frequency HFHigh-fidelityLeakage interferencesPhase gatesSpeed limitSuperconducting qubitsTime-scalesQubits To reference this document use: http://resolver.tudelft.nl/uuid:2e7eab2a-1d85-4ff2-9bfd-cdda9f1b182a TNO identifier 869493 Publisher American Physical Society ISSN 0031-9007 Source Physical Review Letters, 123 (12) Article number 120502 Document type article Files To receive the publication files, please send an e-mail request to TNO Library.