{"paper":{"title":"Hidden Universal Metal in Cuprate Superconductors","license":"http://creativecommons.org/licenses/by/4.0/","headline":"A universal metal sets the critical temperature in all cuprate superconductors via a fixed nuclear relaxation ratio.","cross_cats":[],"primary_cat":"cond-mat.supr-con","authors_text":"Abigail Lee, Juergen Haase","submitted_at":"2026-04-11T09:58:32Z","abstract_excerpt":"Nuclear relaxation is a powerful probe of electronic excitations in superconducting materials. Their emergence from a condensed state near the critical temperature, $T_\\mathrm{c}$, is of particular interest. In cuprate superconductors, the behavior is not yet understood. Here, based on planar Cu and O relaxation data available in the literature, a universal metal is uncovered that reigns in the pseudogap phase, characterised by an average $1/{^{63}T}_{1\\perp} T \\approx 25$/Ks, i.e.\\@ cuprates condense at $T_\\mathrm{c}$ out of this universal metallic density of states. The metal exists up to $T"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"a universal metal, characterized by 1/{^{63}T}_{1⊥} T_c ≈ 25/Ks, found in all materials, i.e. T_c is directly related to the Cu nuclear relaxation rate.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That relaxation data from the literature for different cuprate materials can be directly compared without significant systematic differences in sample quality, measurement conditions, or material-specific effects that would invalidate the claimed universality.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"A universal metal state exists in all cuprate superconductors with 1/^{63}T_{1⊥} Tc approximately constant at 25/Ks, directly tying Tc to Cu nuclear relaxation and explaining doping-dependent anisotropy.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"A universal metal sets the critical temperature in all cuprate superconductors via a fixed nuclear relaxation ratio.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"a78c7ccf6fd932b20b16c7f69ad7bdd4bb868c65bf4cd4cfd1e0ccfb843c1e8b"},"source":{"id":"2604.10133","kind":"arxiv","version":2},"verdict":{"id":"54b7ebde-ecd8-4ddf-89a9-0a0140ae29d9","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-10T15:53:21.853638Z","strongest_claim":"a universal metal, characterized by 1/{^{63}T}_{1⊥} T_c ≈ 25/Ks, found in all materials, i.e. T_c is directly related to the Cu nuclear relaxation rate.","one_line_summary":"A universal metal state exists in all cuprate superconductors with 1/^{63}T_{1⊥} Tc approximately constant at 25/Ks, directly tying Tc to Cu nuclear relaxation and explaining doping-dependent anisotropy.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That relaxation data from the literature for different cuprate materials can be directly compared without significant systematic differences in sample quality, measurement conditions, or material-specific effects that would invalidate the claimed universality.","pith_extraction_headline":"A universal metal sets the critical temperature in all cuprate superconductors via a fixed nuclear relaxation ratio."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.10133/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}