Saturation of superconductivity in cuprates overdoped with high pressure oxygen: Phase diagram with YBa2Cu3O7+δ, δ → 1-

• 成果类型: Article
• 署名作者: Conradson, Steven D.; Dezaneti, Luiz M.; Baldinozzi, Gianguido; Sederholm, Linda; Karppinen, Maarit; Casillas-Trujillo, Luis; Latimer, Matthew; Mueller, Oliver; Gilioli, Edmondo; Bishop, Alan R.; Liu, Juejing; Guo, Xiaofeng; Pacheco, Juan Lezama
• 署名单位: Washington State University; Instituto Federal de Goias (IFG); Universite Paris Saclay; Centre National de la Recherche Scientifique (CNRS); Aalto University; Linkoping University; United States Department of Energy (DOE); Stanford University; SLAC National Accelerator Laboratory; Consiglio Nazionale delle Ricerche (CNR); Istituto dei Materiali per l'Elettronica ed il Magnetismo (IMEM-CNR); United States Department of Energy (DOE); Los Alamos National Laboratory; Stanford University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.2520089123
• 发表日期: 2026-03-10
• 页码: e2520089123
• 关键词: high temperature superconductivity; overdoped cuprates; superconductivity saturation; HIGH-TEMPERATURE SUPERCONDUCTIVITY; crystal-structure; AXIAL-OXYGEN; t-c; single-crystal; APICAL OXYGEN; copper; SR2CUO3+DELTA; YBA2CU3O7-DELTA; optimization

摘要

High temperature superconductivity (HTSC) typically occurs as a dome over a narrow range of doping in its phase diagram. The reaction ofYBa2Cu3O7 with Ag2O2 at >= 800 degrees C and 6 GPa inserts oxygen atoms between the Cu1 sites to form tetragonal YBa2Cu3O8 without significant changes to its overall structure or interatomic distances. The superconductivity inYBa2Cu3O8 is essentially unaffected, with the reduction of the transition temperature by <= 2 K and its superconducting fraction by <= 15% between the O7 and O8 endpoints of the oxygen stoichiometry and associated carrier density.The dome therefore only pertains to compounds doped by cation substitution or presumably interstitial oxygen. Band structure calculations of the fully ordered endpoints show substantial changes in the density of states at the Fermi level because of its shift to lower energy with increasing oxygen stoichiometry. The coincidence of optimum and saturation HTSC at a carrier:CuO2 ratio of approximate to 1/6 implies a direct coupling of HTSC with the lattice such that this value is intrinsic to the superconducting phase. The SC in YBa2Cu3O8 is therefore not only pinned at its optimum values but also separated from the other electronic states so that the additional holes have no measurable effect on the condensate. In addition, the 95 K transition temperature of Sr2CuO3.4 that possesses CuO1.5 ladders instead of CuO2 planes reveals a second distinct behavior of cuprates overdoped with high-pressure oxygen, demonstrating significant gaps in our understanding of HTSC.