The pseudogaps in multiband electron-doped cuprate superconductivity

Abstract

The pseudogap (PG) excitations in the framework of multiband superconductivity are analysed. Calculations for the doping phase diagram of electron-doped cuprate superconductors have been made. A nonrigid multiband model has been used. The interband pairing acts between the upper Hubbard band (UHB) and midgap states created (and shifted upwards) by doping. The appearance of two PG and two phase diagram critical points (CP) is suggested. The larger antinodal PG reflects the destruction of the long-range antiferromagnetic (AF) order. The second, smaller PG is a near-nodal event with exposed doping dependence behind the first CP. It reaches the T$_c$ - dome. Model calculations have been made. The peculiarities of the phase diagram are determined by the doping-stimulated band overlap dynamics. The observation of ,,foreign`` carriers as compared to the ones introduced by doping is expected to start with the vanishing PG.