Melting of magnetic correlations in charge-orbital ordered La(0.5)Sr(1.5)MnO(4) : competition of ferro and antiferromagnetic states

TL;DR

This study investigates how magnetic correlations in La(0.5)Sr(1.5)MnO(4) evolve with temperature, revealing a competition between ferromagnetic and CE-type antiferromagnetic states and their relation to charge-orbital order.

Contribution

It provides new insights into the melting of charge-orbital order and the competition of magnetic states in manganites using neutron scattering techniques.

Findings

CE-type magnetic order disappears with charge-orbital melting

Ferromagnetic correlations resemble metallic manganites

Magnetic fluctuations show temperature-dependent competition

Abstract

The magnetic correlations in the charge- and orbital-ordered manganite La(0.5)Sr(1.5)MnO(4) have been studied by elastic and inelastic neutron scattering techniques. Out of the well-defined CE-type magnetic structure with the corresponding magnons a competition between CE-type and ferromagnetic fluctuations develops. Whereas ferromagnetic correlations are fully suppressed by the static CE-type order at low temperature, elastic and inelastic CE-type correlations disappear with the melting of the charge-orbital order at high temperature. In its charge-orbital disordered phase, La(0.5)Sr(1.5)MnO(4) exhibits a dispersion of ferromagnetic correlations which remarkably resembles the magnon dispersion in ferromagnetically ordered metallic perovskite manganites.