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arXiv:1905.05720 · Physical Review A

Verifying multipartite entangled Greenberger-Horne-Zeilinger states via multiple quantum coherences

Ken Xuan Wei, Isaac Lauer, Srikanth J. Srinivasan, Neereja Sundaresan, Douglas McClure, D.M. Toyli, David C. McKay, Jay Gambetta, Sarah Sheldon

Published Mar 25, 2020• 140 citations
arXivHTMLPDF

Abstract

An 18-qubit GHZ state with multipartite entanglement is prepared and measured on a 20-qubit device. The detection technique used, which is based on measuring multiple quantum coherences, is robust to noise and only requires measuring the population in the ground state.
DOI
10.1103/physreva.101.032343

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