{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"dc197ac246c6d0cb3b24934d70e23b26ed7028d41eae2b037c0b13e21afdc180","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["1f601410322cdcfe00cccad7c945bff94b200a5feac304a2341ddec819eedea6","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"b2bd6597ee2943c893b06c6f280b84b60938e06f11cd8c5ec21c465891355637","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"classification","assisted_by":[],"external_id":"cm.heavy-fermions.kondo-breakdown-vs-sdw","kind":"phenomenon","literature_status":"contested","n":"2","parents":[],"plain":"At a heavy-fermion quantum critical point either magnetism appears while the f electrons stay bound to conduction electrons, or the binding itself (Kondo screening) breaks down; which happens decides the theory.","posed_since":"2001","precise":"For heavy-fermion quantum critical points (CeCu6-xAux, $\\mathrm{YbRh_2Si_2}$, $\\mathrm{CeRhIn_5}$ under pressure, $\\mathrm{CeCoIn_5}$), determine whether criticality is of Hertz-Millis-Moriya spin-density-wave type with Kondo screening intact, or of local (Kondo breakdown) type in which the f electrons leave the Fermi volume at the critical point. An answer classifies the known materials using $\\omega/T$ scaling of the dynamical spin susceptibility, the Fermi-volume change, and the exponents of $C/T$ and $\\rho(T)$.","problem_ref":"1f601410322cdcfe00cccad7c945bff94b200a5feac304a2341ddec819eedea6","references":"","settled_by":"Material-by-material measurements of Fermi volume on both sides of the critical point plus dynamical spin susceptibility scaling, compared with the two theories.","status_note":"","title":"Kondo breakdown versus spin-density-wave criticality in heavy-fermion metals","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"7c557bf7aad981568104a203214150a8a10cf7ea8e26ca8db84344fdf5aa3ac4","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"f58b23405290a0050070ca89e265849ef3141f5907edcce211ebcc2b96babede","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"bIaUJxkyvKK4VLv_RH_RD-RrHDJ2cehMguWuhynmtN6qvgxvqO8dWiRX89u0o-QPKkFXXAz-45xDjejVItuLAA"},"schema":"pubphys.envelope/1"},"record_hash":"7c557bf7aad981568104a203214150a8a10cf7ea8e26ca8db84344fdf5aa3ac4","leaf_index":2838}