Structure of Four Families of Layered Copper-oxide High Tc Superconductors

Abstract

Four major families of copper·oxide based high Tc superconductors have been identified by the following research groups: Bednorz and Muller (1986), Cava et al. (1988), Hor et al. (1987), Maeda et al. (1988), Sheng and Herman (1988) and Wu et al. (1987). It is now well established that the superconductivity is associated with the layers of copper·oxide and that some of the remaining structural building blocks in each primitive cell act as electron acceptors which induce the holes in the copper·oxide layers necessary for superconductivity.