{"paper":{"title":"Magnetic quantum oscillations in YBa$_2$Cu$_3$O$_{6.61}$ and YBa$_2$Cu$_3$O$_{6.69}$ in fields of up to 85 T; patching the hole in the roof of the superconducting dome","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cond-mat.str-el"],"primary_cat":"cond-mat.supr-con","authors_text":"C.H. Mielke, Clarina de la Cruz, Dwight Rickel, Isabel Franke, John Singleton, Moaz Altarawneh, Paul Goddard, Pengcheng Dai, R.D. McDonald, Shiliang Li, Xin Yao","submitted_at":"2009-11-14T05:38:35Z","abstract_excerpt":"We measure magnetic quantum oscillations in the underdoped cuprates YBa$_2$Cu$_3$O$_{6+x}$ with $x=0.61$, 0.69, using fields of up to 85 T. The quantum-oscillation frequencies and effective masses obtained suggest that the Fermi energy in the cuprates has a maximum at $p\\approx 0.11-0.12$. On either side, the effective mass may diverge, possibly due to phase transitions associated with the T=0 limit of the metal-insulator crossover (low-$p$ side), and the postulated topological transition from small to large Fermi surface close to optimal doping (high $p$ side)."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0911.2745","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":""},"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"}