{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"bee3d4f05b0dfff554d084ccdd14c0cd435024c59240af3c9008a009a3753ec1","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["9f23ba26781c93a47988bbf50169733ce5fb29028215d09c02cb666d93c39ec0","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"409b2816832514ba2f5136edb5531044d9b73f823a787b019fd851fbb8e02d58","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"cm.moire-graphene-superconductivity.insulator-sc-relation","kind":"well-posed","literature_status":"partially-resolved","n":"2","parents":[],"plain":"Superconductivity in magic-angle graphene appears next to insulating states, as in cuprates, but devices in which a nearby metal gate screens the electron repulsion lose the insulators and keep the superconductivity, so the two may have different causes.","posed_since":"2018","precise":"Saito et al. (Nature Physics 16, 926, 2020, arXiv:1911.13302) and Stepanov et al. (Nature 583, 2020, doi:10.1038/s41586-020-2459-6) found superconductivity in twisted bilayer graphene without correlated insulators at $\\nu = \\pm2$, for twist angles detuned from 1.1 deg or with metallic gates a few nm away. Determine whether the superconductor and the correlated insulator share an origin (pairing from doping the ordered insulator) or compete for the same flat-band electrons. An answer is the dependence of $T_{c}$ and of the insulating gap on gate-screening length $d$ and twist angle, with the pairing state shown to be the same or different with and without the insulator.","problem_ref":"9f23ba26781c93a47988bbf50169733ce5fb29028215d09c02cb666d93c39ec0","references":"","settled_by":"$T_c$, insulating-gap and gap-symmetry measurements in devices with gate distance $d$ varied from about 1 to 50 nm at fixed twist angle and strain.","status_note":"2020 screening experiments showed superconductivity can exist without the insulators; whether both share one pairing mechanism remains unsettled as of 2026.","title":"Does magic-angle superconductivity require the neighbouring correlated insulator?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"7b87c441cd16a5c8f93a230efcd18ba655ccf6deccc6c01e3e7181f073215c88","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"d27f1af184af9f13f47d0156f238b2832496e495a736a84aa185d19247b1182e","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"CGGdhkC0FDfK3dmeruQz7LLHthg_fCQ7ue809eBpDck2ZaxgDmcK-zEUEdk3VdtBm55zZEZYT2yCDS42cB4GAA"},"schema":"pubphys.envelope/1"},"record_hash":"7b87c441cd16a5c8f93a230efcd18ba655ccf6deccc6c01e3e7181f073215c88","leaf_index":2946}