{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"f06781d797ec273b93c3c66009816c8002e65d8c4d24b4ee3644a264c8f580b8","created":"2026-10-03T07:18:00Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"911a5dc6d2c4008726327c2f5c36cbf69d76481fbeb2cad17e9febaee12d171a","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"classification","assisted_by":[],"external_id":"cm.kitaev-materials.kitaev-111-intermediate","kind":"well-posed","literature_status":"contested","n":"1","parents":[],"plain":"Numerical studies of the ideal antiferromagnetic Kitaev model in a field along the cube diagonal find an extra phase between the low-field spin liquid and the high-field polarized state. Its identity, possibly a gapless spin liquid with a Fermi surface of neutral particles, is disputed.","posed_since":"2018","precise":"Model: H = K sum_<ij>_gamma S^gamma_i S^gamma_j - h sum_i (S^x_i + S^y_i + S^z_i)/sqrt(3), $K > 0$, $S = 1/2$, honeycomb lattice. For the window h_c1 < h < h_c2 found numerically, determine whether the ground state is a gapless $U(1)$ spin liquid with a spinon Fermi surface, a gapped chiral spin liquid of different Chern number, or another phase. An answer gives the classification, its boundaries in $h/K$, and the supporting entanglement and spectral evidence.","problem_ref":null,"references":"","settled_by":"Large-cylinder DMRG, iPEPS or neural-network variational calculations that agree on the gap, entanglement scaling and topological invariants of the intermediate phase.","status_note":"","title":"Nature of the intermediate phase of the antiferromagnetic Kitaev model in a field","topic_ref":"8a920d20c87cdaf1da8d81ec58f05a8787f99b7ca6e234e7f5eef3a4d6c67048"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"bd517604dc4ab2c76ed507ce2348d076749611972449e06a38bac3d30b647f92","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"084b5dcde39ab39ce096034214d586cf844c6de5ba93c7028f2e659ba00c7d11","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"eC2D1Fly7ELcuZyuIk7J3DN-XhU8XoHs_Qh1tiP8J_KvxqSsFcjBuryx3QbH_8aM4arEZhrBhQrK8C7lL0a_Dg"},"schema":"pubphys.envelope/1"},"record_hash":"bd517604dc4ab2c76ed507ce2348d076749611972449e06a38bac3d30b647f92","leaf_index":1056}