• 5 February 1997
Abstract
On the basis of the Boson-Fermion model we have previously shown that the density of states of the electrons develops a pseudo gap at the Fermi energy in the normal state. We show here that concomitantly the spectral function for electrons near the Fermi surface develops a three-peak structure upon lowering the temperature and that the Fermi momentum increases due to a thermal rearangement of the Fermion and Boson densities. These features are direct consequences of a two component scenario involving preformed pairs with an amplitude of the order parameter which is finite above Tc and global phase coherence setting in only below Tc.