Electronic and structural phase separation in strongly correlated sytems

Abstract

We review recent work on frustrated electronic phase separation in strongly correlated systems and the connection between electronic phase separation at a mesoscopic scale and structural phase separation at larger scales associated with volume instabilities. The former is due to the competition between phase separation tendencies and the long-range Coulomb interaction and surface energy effects. Above a critical value of the Coulomb interaction electronic phase separation is not possible and a volume instability arises. The system shows the tendency to phase separate into two neutral phases with different unit cell volumes.