Momentum Distribution Functions in a One-Dimensional Extended Periodic Anderson Model

We study the momentum distribution of the electrons in an extended periodic Anderson model, where the interaction,Ucf, between itinerant and localized electrons is taken into account. In the symmetric half-filled model, due to the increase of the interorbital interaction, thefelectrons become more and more delocalized, while the itinerancy of conduction electrons decreases. Above a certain value ofUcfthefelectrons become again localized together with the conduction electrons. In the less than half-filled case, we observe thatUcfcauses strong correlations between thefelectrons in the mixed valence regime.