Certifying bipartite entanglement on a superconducting processor from a corrected QAOA cost layer
Carlos-Miguel Lorenzo · arXiv (Cornell University) · 2026
Reproducibility deposit accompanying the manuscript "Certifying bipartite entanglement on a superconducting processor from a corrected QAOA cost layer" (target: Quantum). The single primary certificate is the PSD-constrained reduced-state tomographic negativity on the good edge 4-5 at depth p=1: day-level grand mean 0.077, PSD-constrained BCa 95% CI [0.065, 0.091], 6/6 days; controls do not certify (degraded edge 6-8 BCa [0.000, 0.007]; J=0 twin equivalent to 0). A p3-PPT randomized-measurement (classical-shadow) witness W = p2^2 - p3 = 0.0105, canonical BCa 95% CI [0.0060, 0.0161], is reported as a consistent but underpowered secondary reading on Red (not an independent certification: at the measured magnitude the near-pure-separable null needs N_U ~ 12,672 settings vs the 800 run). The deposit includes a pre-registered causal manipulation campaign (data/r2_causal/): a 3-coupler x 2-session dose-response of certified negativity against the manipulated CZ pulse amplitude on a fixed |Phi+> Bell preparation, with per-session slopes positive and each 95% CI excluding zero, a DerSimonian-Laird three-edge random-effects pool, and pre-committed J=0 CZ-off twins at negativity ~ 0. Every circuit passes an anti-regression statevector guardrail to the pre-registered 1e-9 bound (worst deviation 8.4e-15 tomography / 8.33e-16 RM; 0 aborts). Contents: sealed live-B pre-registration + REGISTRATION.md; the executed Ising instances and frozen angles (instances_liveB.json); six daily tomography manifests + raw per-shot .out (tomography jobs 11479-11484); the RM witness toolchain and raw outputs (jobs 11608-11611); the causal campaign (six sealed run directories, each with its own RFC-3161-timestamped PREREGISTRATION.json and local CHECKSUMS.sha256); Red runcard/evidence archive and BSC daily autocalibration; the full analysis + figure pipeline; and AMENDMENTS.md (byte-level sealed-artefact reconciliation, RFC-3161 timestamped). Scope: every reported quantity is regenerable for the Red superconducting device only; the cross-architecture Euro-Q-Exa corroboration is held under the hosting facility's policy and is outside this deposit. The obsolete 8-variable design pre-registration and its instance set are quarantined under obsolete/ (SUPERSEDED.txt) and are retained only as part of the honest amendment trail. Integrity: CHECKSUMS.sha256 lists the SHA-256 of every deposit file (181 entries, 181/181 verified).