{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"98f9c65581dad8192f4834b9233596432d54c6ea8981f4ad7b360a89283f10c1","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":["ai:gpt-5.5"],"kind":"seed"},"parents":["ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b","dd0e9821c69027dfa25a1569e5f3d8c9d179cda67bd7ec39e5ca03e298f1676e"],"salt":"3a14a347f3b191b0693cc9599fe7c0f3e67c0b76283f209d9cdc9f7bbd60b4dd","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":["ai:gpt-5.5"],"external_id":"cm.kitaev-materials.rucl3-spin-hamiltonian","kind":"well-posed","literature_status":"contested","n":"2","parents":[],"plain":"Interpreting any $\\alpha$-RuCl3 experiment requires its spin couplings, yet published fits disagree even on which coupling is largest. Without an agreed set, claims of spin-liquid behavior cannot be checked against theory.","posed_since":"","precise":"Determine the exchange constants of alpha-RuCl3 in $H = \\sum$ over nearest-neighbor bonds $\\langle ij\\rangle$ of type $\\gamma$ of [$J S_i . S_j + K S^{\\gamma}_{i} S^{\\gamma}_{j} + \\Gamma (S^{\\alpha}_{i} S^{\\beta}_{j} + S^{\\beta}_{i} S^{\\alpha}_{j}) + \\Gamma'$ (terms mixing $\\gamma$ with $\\alpha$ and $\\beta$)] $+ J3 \\sum$ over third neighbors of $S_i . S_j$, with $(\\alpha, \\beta, \\gamma)$ a permutation of $(x, y, z)$, from a joint fit of inelastic neutron spectra, THz and ESR modes, the field-angle dependence of the critical field and the high-field magnon spectrum. An answer is one parameter set with error bars consistent with all these data, including the sign of $K$ and the ratio $K/\\Gamma$.","problem_ref":"dd0e9821c69027dfa25a1569e5f3d8c9d179cda67bd7ec39e5ca03e298f1676e","references":"","settled_by":"A global fit of neutron, THz, ESR, magnetization and magnetostriction data using quantum many-body (beyond linear spin-wave) calculations of the spectra that yields a unique parameter set.","status_note":"Proposed parameter sets range from Kitaev dominated to regions with a large off-diagonal $\\Gamma$ term; Maksimov and Chernyshev (Physical Review Research 2020) argued for the latter.","title":"The minimal spin Hamiltonian of $\\alpha$-RuCl3","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"0554b259c9b50af9d4a577b9fdfa82d9f114a025085767a52dcb6e6e66a6e5fb","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"602a8e6a23bb74520b641dc39c46a2a612c1bb6e7e0075b9b15ffd66bc6ab294","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"OYCPnpsjguRPmoofw3YOr1yDpGv-JcWlnlei4a8RUKFOW28Ano2a79BocvbafS-6GmjYRAwQ5-E0PLyArZ68Bw"},"schema":"pubphys.envelope/1"},"record_hash":"0554b259c9b50af9d4a577b9fdfa82d9f114a025085767a52dcb6e6e66a6e5fb","leaf_index":2900}