{"paper":{"title":"Very high upper critical fields in MgB2 produced by selective tuning of impurity scattering","license":"","headline":"","cross_cats":[],"primary_cat":"cond-mat.supr-con","authors_text":"A. Gurevich, A. Siri, C. B. Eom, C. Mielke, D.C. Larbalestier, D. M. Kim, E. E. Hellstrom, J. Giencke, J. H. Choi, K. H. Kim, L. D. Cooley, L. J. Belenky, M. K. Lee, S. D. Bu, S. Patnaik, V. Braccini, W. Tian, X.Q. Pan, X. Song","submitted_at":"2003-05-20T14:59:13Z","abstract_excerpt":"We report a significant enhancement of the upper critical field $H_{c2}$ of different $MgB_2$ samples alloyed with nonmagnetic impurities. By studying films and bulk polycrystals with different resistivities $\\rho$, we show a clear trend of $H_{c2}$ increase as $\\rho$ increases. One particular high resistivity film had zero-temperature $H_{c2}(0)$ well above the $H_{c2}$ values of competing non-cuprate superconductors such as $Nb_3Sn$ and Nb-Ti. Our high-field transport measurements give record values $H_{c2}^\\perp (0) \\approx 34T$ and $H_{c2}\\|(0) \\approx 49 T$ for high resistivity films and "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"cond-mat/0305474","kind":"arxiv","version":2},"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/cond-mat/0305474/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"}