UNIVERSAL RELATIONSHIP BETWEEN TC AND THE HOLE CONTENT IN P-TYPE CUPRATE SUPERCONDUCTORS

A critical analysis of experimental data reveals a universal relationship between T(c)/T(c,max) and hole content among the p-type high-T(c) cuprate superconductors. Each individual compound is characterized by the value of its maximum T(c), T(c,max), while the variation of T(c)/T(c,max) with the hole content is independent of the compound considered. The universal curve is characterized by a plateau, rather than a parabola, with sharp bends at both sides. The T(c) versus hole content curve has a close relation to hole contents determined by ordered arrangements of holes in the two-dimensional CuO2 layer.