{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"41d10597cbddace1623b415c04e7697f98ff7b4c0cd62c3882f470188bf11132","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["4e26afc00b7011defe0fb8dd7e4edec02af962c3bb628d77fb25bedb149ad4e3","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"d45a5d1f2c08b01e375855522150571a20fc38d3f6ad24a91174f043ea02e41b","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"cm.moire-graphene-superconductivity.pairing-mechanism","kind":"phenomenon","literature_status":"contested","n":"2","parents":[],"plain":"Superconductivity needs electrons to pair up despite repelling each other, and in magic-angle graphene it is unknown whether lattice vibrations (phonons) or the electrons' own interactions supply the attraction.","posed_since":"2018","precise":"Twisted bilayer graphene at $\\theta \\sim 1.05-1.15\\,\\mathrm{deg}$ superconducts with $T_c$ up to $\\sim 3\\,\\mathrm{K}$ near filling $\\nu = -2 - \\delta$ ($\\nu$ = electrons per moire cell measured from charge neutrality). Determine the dominant pairing interaction (intervalley K-point optical phonons, other phonons, spin or valley fluctuations, Coulomb-driven Kohn-Luttinger pairing, or a combination) and the order-parameter symmetry. An answer is a microscopic model that reproduces the measured $T_c(\\nu, \\theta)$, tunnelling gap spectrum and superfluid stiffness without retuned parameters.","problem_ref":"4e26afc00b7011defe0fb8dd7e4edec02af962c3bb628d77fb25bedb149ad4e3","references":"","settled_by":"A phase-sensitive gap-symmetry measurement plus an isotope or phonon-engineering test, combined with a parameter-free calculation reproducing $T_{c}(\\nu, \\theta)$.","status_note":"2024 photoemission (Chen et al., Nature 636, 342) found flat-band replicas from strong coupling to a $\\sim 150\\,\\mathrm{meV}$ K-point phonon, while 2025 superfluid-stiffness data show power-law temperature dependence pointing to unconventional pairing; no consensus as of 2026.","title":"What binds electron pairs in magic-angle graphene superconductors?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"adf01e2e7bc376e03fe3c7325b91ba74b776e8cdb7cba6cd3f0452ec9d1e35e7","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"80d987f4da5b5a1b1ae8adca68abd688d1cb2b855558a76b7cbe855a834f133f","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"ZNiOd68iAjamBYaQOvCk_FmNF76_mH868nVc7ZTQJm80I8tCljY7HsiN6w0zs_yEvIQp7F_0sHP9A_wT1fd7DQ"},"schema":"pubphys.envelope/1"},"record_hash":"adf01e2e7bc376e03fe3c7325b91ba74b776e8cdb7cba6cd3f0452ec9d1e35e7","leaf_index":2950}