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

• Published in: arXiv.org
• Main Authors: Burrell, A H, Szwer, D J, Webster, S C, Lucas, D M
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 07.04.2010
• Subjects: Crosstalk; Error analysis; Physics - Quantum Physics
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.0906.3304

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.