Experimental predictions for the normal state of electron-doped high-temperature superconductors

The discovery of n-type high-temperature superconductors implies an electron-hole symmetry that is missing in two-band descriptions of the copper oxides. At the same time, several peculiar differences between the new electron-carriers and the older hole-carriers cannot be explained within the Cu-based single-band Hubbard model. It is shown that these differences are expected within a dopant-induced valence transition mechanism proposed earlier, in which a first-order valence transition accompanies the antiferromagnetic-superconductor transition in the copper oxides. Based on this theoretical mechanism, a large number of explicit testable experimental predictions are made for the normal state of Nd(Ce)CuO.