| 摘要 |
Novel superconductive oxides are disclosed. The oxides all have layered perovskite-like crystal structure and manifest superconductivity above about 77K. An exemplary material has composition Bi2.2Sr2Ca0.8Cu2O8. Other materials are described by the nominal formula X2+xMn-xCun-1O2+2n+x/2+/- delta , where X typically is Bi, or Bi together with Pb or other appropriate substituent, M is one or more divalent ion or mixture of monovalent and trivalent ion, n is an integer greater than 3, x=p/q, where p and q are integers and p<q, and delta is less than 0.5. Associated with the inventive compounds typically is a superlattice structure, with Tc of the compound typically being correlated with the superlattice spacing. The inventive compounds are typically relatively ductile.
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