Acta Phys. -Chim. Sin. ›› 1991, Vol. 7 ›› Issue (06): 641-645.doi: 10.3866/PKU.WHXB19910601

• Communication •     Next Articles

Structure and Superconductivity on N-Type Superconductors (Ln1.85Ce0.15)CuO4-y

Zhang Yu-Fen; Lin Qin; Liu Zun-Xiao   

  1. Laboratory for Applied Physical Chemistry, Institute of Physical Chemistry, Peking University, Beijing 100871; Department of Physics, Peking University
  • Received:1991-04-27 Revised:1991-07-06 Published:1991-12-15
  • Contact: Zhang Yu-Fen

Abstract: In comparison with the structure of hole-doped T phase (La_(2-x)Sr_x)CuO_4, electron-doped superconductors (Ln_(1.85)Ce_(0.15))CuO_(4-y), Ln=Pr, Nd, Sm, Eu, possess T phase structure with tetragonal I4/mmm symmetry. Their structural features are that the Cu ion is coordinated by four oxygen ions in square planar form and the Ln ion is located in octa-coordinate cubic site in the fluorite type LnO_2Ln duble layers. In this paper, the effects of preparation condition and cation substitution on the structure and superconductivity have been studied. Average ionic radius of Ln-site is limited in very narrow range. It can be changed by the substitution of larger or smaller ions. Its dimension is very important for structural type, structural stability under N_2 atmosphere and superconductivity.

Key words: Electron-doped Supereonductors, (Ln1.85Ce0.15)CuO4-y, Ln=Pr,Nd,Sm,Eu,Structure, Superconductivity