{"paper":{"title":"Superconducting properties of ultrapure niobium","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["cond-mat.mtrl-sci"],"primary_cat":"cond-mat.supr-con","authors_text":"K.-H. Bertel, N. E. Alekseevskiy, V. I. Nizhankovskiy","submitted_at":"2025-06-02T05:19:16Z","abstract_excerpt":"The results of determination of critical magnetic fields, magnetization curves and critical currents of niobium samples of different purity are presented. It is shown that ultrapure niobium near Tc is a superconductor of the first type and becomes a superconductor of the second type with decreasing temperature due to the temperature dependence of the Ginzburg-Landau parameters. The dependence of the hysteresis of the magnetization curves of massive samples on the surface state is investigated. A comparison of the superconducting parameters with the parameters of the electron spectrum of niobiu"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2506.01330","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/2506.01330/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"}