Phase separation and the segregation principle in the infinite-U spinless Falicov-Kimball model

TL;DR

This paper provides an exact solution to a simplified model of crystalline formation with electronic degrees of freedom, revealing phase transitions and segregation phenomena relevant to understanding charge ordering in cuprates.

Contribution

It presents an exact solution of the infinite-U spinless Falicov-Kimball model in high dimensions, highlighting phase separation and transition behaviors.

Findings

Presence of both first- and second-order phase transitions

Phase separation or segregation phenomena observed

Spinodal-decomposition temperature follows a scaling law

Abstract

The simplest statistical-mechanical model of crystalline formation (or alloy formation) that includes electronic degrees of freedom is solved exactly in the limit of large spatial dimensions and infinite interaction strength. The solutions contain both second-order phase transitions and first-order phase transitions (that involve phase-separation or segregation) which are likely to illustrate the basic physics behind the static charge-stripe ordering in cuprate systems. In addition, we find the spinodal-decomposition temperature satisfies an approximate scaling law.