Charge-ordered ferromagnetic phase in manganites

TL;DR

This paper proposes a mechanism for the emergence of a charge-ordered ferromagnetic phase in manganites, based on double exchange with disorder, modeled through advanced theoretical methods, revealing two phase transitions.

Contribution

It introduces a combined model using Ising double-exchange and Falicov-Kimball models to explain charge-ordered ferromagnetism in manganites, analyzed via dynamical mean-field theory.

Findings

Identification of two successive phase transitions: ferromagnetic and charge ordering.

Stabilization of charge-ordered ferromagnetic phase at low temperatures.

Explicit calculation of charge and spin correlation functions.

Abstract

A mechanism for charge-ordered ferromagnetic phase in manganites is proposed. The mechanism is based on the double exchange in the presence of diagonal disorder. It is modeled by a combination of the Ising double-exchange and the Falicov-Kimball model. Within the dynamical mean-field theory the charge and spin correlation function are explicitely calculated. It is shown that the system exhibits two successive phase transitions. The first one is the ferromagnetic phase transition, and the second one is a charge ordering. As a result a charge-ordered ferromagnetic phase is stabilized at low temperature.