{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"322785944206ca59dc8405779090b82997a4b9a5a2fd0b2f1a8058deedabe599","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["1556471aceff89e4ac7ba529a6a220bdd6a394873c0015f3b653bed4823e071c","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"0df8ec8ad3731bea540b76023380974cd949e78c681add53a951594b3015b30b","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"identification","assisted_by":[],"external_id":"cm.dilute-superconductivity.yptbi-j32-pairing","kind":"well-posed","literature_status":"open","n":"2","parents":[],"plain":"In the half-Heusler compound YPtBi, the electrons near the Fermi level carry total angular momentum $3/2$ instead of the usual $1/2$, so a pair can have total angular momentum 0, 1, 2 or 3, not only the usual 0 or 1. Experiments indicate lines of zero gap, but which pairing state forms is unknown.","posed_since":"2016","precise":"YPtBi ($\\Gamma_{8}$ band, $n \\sim 2 \\times 10^{18}\\ \\mathrm{cm}^{-3}$, $T_{c} \\sim 0.78\\ \\mathrm{K}$) shows a penetration depth linear in $T$ suggesting line nodes (Kim et al., Science Advances 2018) and an upper critical field above the Pauli limit. Identify the order parameter among $j = 3/2$ pairing channels (septet $J = 3$, quintet $J = 2$, singlet-septet mixture allowed by broken inversion) and its pairing interaction. An answer is a symmetry identification consistent with penetration depth, NMR, critical-field and tunneling data.","problem_ref":"1556471aceff89e4ac7ba529a6a220bdd6a394873c0015f3b653bed4823e071c","references":"","settled_by":"Phase-sensitive or angle-resolved gap measurements (e.g. field-angle thermal conductivity or Josephson interferometry) that discriminate between the $J = 2$ and $J = 3$ candidate states.","status_note":"","title":"Pairing state of total angular momentum $3/2$ fermions in YPtBi","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"5a34c28db04709ad67220ede50185402af75fbefe8108194755f3780803ae43d","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"e3f7eca51519a488c19b3d69f372dca65ff2c04097dfc97f33a9f55af89cebae","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"dERbHH3P7r8RB69-bn96Sh9snZYCW4EoRHU2mx3y1tVR68qDg6dnDFF-wjtmzjfZjHOX2rJAhXAO_AyuA1ACAw"},"schema":"pubphys.envelope/1"},"record_hash":"5a34c28db04709ad67220ede50185402af75fbefe8108194755f3780803ae43d","leaf_index":2750}