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arXiv · 1509.02815

Characterizing a Four-Qubit Planar Lattice for Arbitrary Error Detection

Jerry M. Chow·Srikanth J. Srinivasan·Easwar Magesan·A D. Corcoles·David W. Abraham·Jay M. Gambetta·Matthias Steffen
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Abstract

Quantum error correction will be a necessary component towards realizing scalable quantum computers with physical qubits. Theoretically, it is possible to perform arbitrarily long computations if the error rate is below a threshold value. The two-dimensional surface code permits relatively high fault-tolerant thresholds at the ~1% level, and only requires a latticed network of qubits with nearest-neighbor interactions. Superconducting qubits have continued to steadily improve in coherence, gate, and readout fidelities, to become a leading candidate for implementation into larger quantum networks. Here we describe characterization experiments and calibration of a system of four superconducting qubits arranged in a planar lattice, amenable to the surface code. Insights into the particular qubit design and comparison between simulated parameters and experimentally determined parameters are given. Single- and two-qubit gate tune-up procedures are described and results for simultaneously benchmarking pairs of two-qubit gates are given. All controls are eventually used for an arbitrary error detection protocol described in separate work [Corcoles et al., Nature Communications, 6, 2015]

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Jerry M. Chow, Srikanth J. Srinivasan, Easwar Magesan, A D. Corcoles, David W. Abraham, Jay M. Gambetta, Matthias Steffen. 2015-09-09. Characterizing a Four-Qubit Planar Lattice for Arbitrary Error Detection. https://doi.org/10.1117/12.2192740

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