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arXiv · 1202.5344

Complete universal quantum gate set approaching fault-tolerant thresholds with superconducting qubits

Jerry M. Chow·Jay M. Gambetta·A. D. Corcoles·Seth T. Merkel·John A. Smolin·Chad Rigetti·S. Poletto·George A. Keefe·Mary B. Rothwell·J. R. Rozen·Mark B. Ketchen·M. Steffen
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Abstract

We use quantum process tomography to characterize a full universal set of all-microwave gates on two superconducting single-frequency single-junction transmon qubits. All extracted gate fidelities, including those for Clifford group generators, single-qubit pi/4 and pi/8 rotations, and a two-qubit controlled-NOT, exceed 95% (98%), without (with) accounting for state preparation and measurement errors. Furthermore, we introduce a process map representation in the Pauli basis which is visually efficient and informative. This high-fidelity gate set serves as another critical building block towards scalable architectures of superconducting qubits for error correction schemes.

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Jerry M. Chow, Jay M. Gambetta, A. D. Corcoles, Seth T. Merkel, John A. Smolin, Chad Rigetti, S. Poletto, George A. Keefe, Mary B. Rothwell, J. R. Rozen, Mark B. Ketchen, M. Steffen. 2012-02-23. Complete universal quantum gate set approaching fault-tolerant thresholds with superconducting qubits. https://doi.org/10.1103/physrevlett.109.060501

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