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