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arXiv · 1109.6735

Characterization of a two-transmon processor with individual single-shot qubit readout

A. Dewes·F. R. Ong·V. Schmitt·R. Lauro·N. Boulant·P. Bertet·D. Vion·D. Esteve
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Abstract

We report the characterization of a two-qubit processor implemented with two capacitively coupled tunable superconducting qubits of the transmon type, each qubit having its own non-destructive single-shot readout. The fixed capacitive coupling yields the \sqrt{iSWAP} two-qubit gate for a suitable interaction time. We reconstruct by state tomography the coherent dynamics of the two-bit register as a function of the interaction time, observe a violation of the Bell inequality by 22 standard deviations after correcting readout errors, and measure by quantum process tomography a gate fidelity of 90%.

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A. Dewes, F. R. Ong, V. Schmitt, R. Lauro, N. Boulant, P. Bertet, D. Vion, D. Esteve. 2011-09-30. Characterization of a two-transmon processor with individual single-shot qubit readout. https://doi.org/10.1103/physrevlett.108.057002

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