Variation of crystal symmetry, superconductivity and weak ferromagnetism in (R1-yGdy)1.85Ce0.15CuO 4-δ (R = Nd, Eu) cuprates

B. N. Lin*, H. C. Chiang, Y. H. Lin, H. B. Yang, Y. Y. Hsu, H. M. Luo, H. C. Ku


研究成果: 雜誌貢獻會議論文同行評審


Metal-insulator transition in the Gd-doped (R1-yGdy)1.85Ce0.15CuO 4-δ systems occurred around y ∼ 0.1 for R = Eu and y ∼ 0.65 for R = Nd with a simultaneous structural transition from the tetragonal T′-phase (space group I4/mmm) to an orthorhombic O′-phase (Acam, a0 ≤ b0 ∼ √2at). The structural distortion is due to the lattice mismatch between smaller (R,Gd,Ce)2O2 layer and CuO2 plane which results in an oxygen distortion in the otherwise perfect CuO2 square plane. The phase diagram indicates that the superconductivity can only occur in the metallic T′-phase cuprates where the metallic state is controlled by a delicate balance between oxygen reduction and structural stability. The Cu2+ weak-ferromagnetic/canted-antiferromagnetic (WF/CAF) order observed in the insulating region is the direct result of non-180° α(Cu-O-Cu) canting angle of the O′-phase.

頁(從 - 到)922-923
期刊Physica B: Condensed Matter
出版狀態已發佈 - 2000
事件Yamada Conference LI - The International Conference on Strongly Correlated Electron Systems (SCES '99) - Nagano, 日本
持續時間: 1999 八月 241999 八月 28

ASJC Scopus subject areas

  • 電子、光磁材料
  • 凝聚態物理學
  • 電氣與電子工程


深入研究「Variation of crystal symmetry, superconductivity and weak ferromagnetism in (R<sub>1-y</sub>Gd<sub>y</sub>)<sub>1.85</sub>Ce<sub>0.15</sub>CuO <sub>4-δ</sub> (R = Nd, Eu) cuprates」主題。共同形成了獨特的指紋。