{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"f7b6cf39679bca00ee883110022e1180ecb9fc8395ab7c818c0efb659f80119d","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":["ai:gpt-5.5"],"kind":"seed"},"parents":["a86192b2af51a2db41ce759971b8e2a9b81ef03f1564f2469e0e1b7d953d803a","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"2d370d0a675441f041eeba3852e92124d70c747bd773421737bc5e4589dfe928","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":["ai:gpt-5.5"],"external_id":"cm.strange-metals.hall-angle","kind":"phenomenon","literature_status":"contested","n":"2","parents":[],"plain":"In cuprates the resistance grows linearly with temperature while the Hall angle, the deflection of current by a magnetic field, behaves as if a second scattering rate grows as temperature squared.","posed_since":"1991","precise":"In optimally doped cuprates $\\rho_{xx} \\sim T$ while $\\cot(\\theta_{H}) = \\rho_{xx}/\\rho_{xy} \\sim A + B T^{2}$ over a wide range. Determine whether this requires two distinct relaxation rates (transport and Hall) or follows from a single anisotropic scattering rate on a Fermi surface with hot and cold regions. An answer is a model that reproduces both laws and their doping dependence with one parameter set.","problem_ref":"a86192b2af51a2db41ce759971b8e2a9b81ef03f1564f2469e0e1b7d953d803a","references":"","settled_by":"Angle-dependent magnetoresistance mapping of the momentum-resolved scattering rate, fed into a Boltzmann or non-quasiparticle calculation that yields both $\\rho_{xx}(T)$ and $\\operatorname{cot}(\\theta_{H})(T)$.","status_note":"","title":"Why Hall angle and resistivity follow different temperature laws","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"925ca6c6d44c7d8735746ba41f9c7200519394f3e014fbd1ceaa9602bef6bd24","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"f7f8c4396f4bd0af93633ffedfa625171ffdf42473258743bcaf7a74c0c0ea83","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"b7ap89u7ZsoDo_x4j4hZeKoONfBM-usHVyBVdGfh1dc2CTc9q_1be2gwv8xGbgNO4Ltm8tGLqZKyA_fvZ0JTDw"},"schema":"pubphys.envelope/1"},"record_hash":"925ca6c6d44c7d8735746ba41f9c7200519394f3e014fbd1ceaa9602bef6bd24","leaf_index":3060}