PROPERTIES OF HIGH-TEMPERATURE SUPERCONDUCTORS IN A TWO-BAND MODEL WITH THE DOPING-DEPENDENT ELECTRON SPECTRUM

Abstract. A simple model of interband superconductivity, incorporating a basic band and a doping created one (constant total number of states), is considered, keeping in mind the two-component scenario of high-Tc superconductivity. The dependences of Tc, its isotope exponent, superconductivity gaps, etc. on doping are calculated using an illustrative set of parameters. The observed types of behaviour are reproduced. Diminishing gap ratios with hole doping have been found. In the one-particle excitation spectrum the peak–dip–hump type complex can be identified. In spite of crude approximations the model reflects, in general, the experimental findings on high-Tc cuprates. Two-band models will remain a channel for looking for the high-Tc mechanism. Key words: high-temperature superconductivity, two-band models, doping, gaps. 1