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arXiv:2209.00678

An entanglement-based volumetric benchmark for near-term quantum hardware

Kathleen E. Hamilton, Nouamane Laanait, Akhil Francis, Sophia E. Economou, George S. Barron, Kübra Yeter Aydeniz, Titus Morris, Harrison Cooley, Muhun Kang, Alexander F. Kemper, Raphael C. Pooser

Published Sep 1, 2022• 2 citations
arXivHTMLPDF

Abstract

We introduce a volumetric benchmark for near-term quantum platforms based on the generation and verification of genuine entanglement across n-qubits using graph states and direct stabilizer measurements. Our benchmark evaluates the robustness of multipartite and bipartite n-qubit entanglement with respect to many sources of hardware noise: qubit decoherence, CNOT and swap gate noise, and readout error. We demonstrate our benchmark on multiple superconducting qubit platforms available from IBM (ibmq_belem, ibmq_toronto, ibmq_guadalupe and ibmq_jakarta). Subsets of $n<10$ qubits are used for graph state preparation and stabilizer measurement. Evaluation of genuine and biseparable entanglement witnesses we report observations of $5$ qubit genuine entanglement, but robust multipartite entanglement is difficult to generate for $n>4$ qubits and identify two-qubit gate noise as strongly correlated with the quality of genuine multipartite entanglement.

DOI
10.48550/arxiv.2209.00678

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