New Classification Method for Layered Copper Oxide Compounds and Its Application to Design of New High T_c Superconductors

Abstract

Structures of layered copper oxide compounds and relating high-temperature superconductors are classified by using the concept of the block layer which can isolate each CuO2-sheet and control carrier density within the Cu-O plane. Particular emphasis is laid on the Cu-O network dependent physico-chemical properties which are entirely governed by ordering and combination of constituent block layers. By the new classification method, structures and carrier-doping characteristics are predicted for prospective but hitherto unknown CuO2-layered superconductors. Possible importance of the concept of the block layer is pointed out in epitaxial growth of superconducting structures.