Lattice and superexchange effects in doped CMR manganites

TL;DR

This paper investigates how lattice effects, including electron-phonon coupling and superexchange interactions, influence charge, orbital, and spin correlations in doped CMR manganites, affecting their magnetic and electronic properties.

Contribution

It provides new insights into the role of lattice degrees of freedom and superexchange interactions in the behavior of doped CMR manganites.

Findings

Electron-phonon coupling promotes charge carrier trapping.

Orbital polaron patterns disappear with doping.

Ferromagnetism breaks down at the CMR transition.

Abstract

We report on the influence of the lattice degrees of freedom on charge, orbital and spin correlations in colossal magnetoresistance (CMR) manganites. For the weakly doped compounds we demonstrate that the electron-phonon coupling promotes the trapping of charge carriers, the disappearance of the orbital polaron pattern and the breakdown of ferromagnetism at the CMR transition. The role of different superexchange interactions is explored.