Nanoscale phase separation in manganites

TL;DR

This paper investigates nanoscale phase separation in manganites using the double exchange model, revealing instability of the homogeneous state and the formation of ferromagnetic droplets within an antiferromagnetic matrix, influenced by quantum effects.

Contribution

It demonstrates the instability of the homogeneous canted state and analyzes quantum effects on ferromagnetic polarons in manganites, providing new insights into phase separation mechanisms.

Findings

Homogeneous canted state is unstable to phase separation.

Formation of small ferromagnetic droplets within antiferromagnetic matrix.

Quantum effects influence the stability and formation threshold of polarons.

Abstract

We study the possibility of nanoscale phase separation in manganites in the framework of the double exchange model. The homogeneous canted state of this model is proved to be unstable toward the formation of small ferromagnetic droplets inside an antiferromagnetic insulating matrix. For the ferromagnetic polaronic state we analyze the quantum effects related to the tails of electronic wave function and a possibility of electron hopping in the antiferromagnetic background. We find that these effects lead to the formation of the threshold for the polaronic state.