{"paper":{"title":"In-plane spin excitation anisotropy in the paramagnetic phase of NaFeAs","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cond-mat.supr-con","authors_text":"A. D. Christianson, Chenglin Zhang, Guotai Tan, Louis-Pierre Regnault, Pengcheng Dai, Scott V. Carr, Songxue Chi, Tao Xiang, Yu Song","submitted_at":"2013-10-04T01:08:05Z","abstract_excerpt":"We use unpolarized and polarized inelastic neutron scattering to study low-energy spin excitations in NaFeAs, which exhibits a tetragonal-to-orthorhombic lattice distortion at $T_s\\approx 58$ K followed by a collinear antiferromagnetic (AF) order below $T_N\\approx 45$ K. In the AF ordered state ($T<T_N$), spin waves are entirely c-axis polarized below $\\sim$10 meV, exhibiting a gap of $\\sim4$ meV at the AF zone center and disperse to $\\sim$7 meV near the c-axis AF zone boundary. On warming to the paramagnetic state with orthorhombic lattice distortion ($T_N<T<T_s$), spin excitations become ani"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1310.1143","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/1310.1143/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}