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arXiv · 0906.3304

Scalable simultaneous multi-qubit readout with 99.99% single-shot fidelity

A. H. Burrell·D. J. Szwer·S. C. Webster·D. M. Lucas
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Abstract

We describe single-shot readout of a trapped-ion multi-qubit register using space and time-resolved camera detection. For a single qubit we measure 0.9(3)x10^{-4} readout error in 400us exposure time, limited by the qubit's decay lifetime. For a four-qubit register (a "qunybble") we measure an additional error of only 0.1(1)x10^{-4} per qubit, despite the presence of 4% optical cross-talk between neighbouring qubits. A study of the cross-talk indicates that the method would scale with negligible loss of fidelity to ~10000 qubits at a density <~1 qubit/um^2, with a readout time ~1us/qubit.

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A. H. Burrell, D. J. Szwer, S. C. Webster, D. M. Lucas. 2010-04-07. Scalable simultaneous multi-qubit readout with 99.99% single-shot fidelity. https://doi.org/10.1103/physreva.81.040302

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