Phase separation in the strongly correlated Falicov-Kimball model in infinite dimensions

Phase separation in the strongly correlated Falicov-Kimball model in infinite dimensions is examined. We show that the phase separation can occur for any values of the interaction constant J <Superscript>*</Superscript> when the site energy ε <Superscript>0</Superscript> of the localized electrons is equal to zero. Electron-poor regions always have homogeneous state and electron-rich regions have chessboard state for J <Superscript>0</Superscript> ≥ 0.03, chessboard state or homogeneous state in dependence upon temperature for 0 > J <Superscript>*</Superscript> > 0.03 and homogeneous state for J <Superscript>*</Superscript>=0. For J <Superscript>*</Superscript>=0 and T=0, phase separation (segregation) occurs at −1 > ε <Superscript>0</Superscript> > 0. The obtained results are exact for the Bethe lattice with infinite number of the nearest neighbours. Copyright Società Italiana di Fisica, Springer-Verlag 1999