Universal features of charge and spin order in a half-doped layered perovskite

TL;DR

This study reveals universal characteristics of charge and spin ordering in half-doped layered perovskite La$_{1.5}$Sr$_{0.5}$CoO$_4$, highlighting both common features and subtle differences across samples.

Contribution

It demonstrates that certain charge and spin order features are universal in this material, regardless of sample preparation, while others vary subtly.

Findings

Ordered states are short-range and glassy.

Spin incommensurability is a universal feature.

Correlation lengths differ between samples.

Abstract

We have investigated the peculiar structure of charge and spin ordering in the half-doped layered perovskite oxide La$_{1.5}$Sr$_{0.5}$CoO$_4$ by elastic neutron scattering. Two samples with different preparation histories were studied. We find that the generic features of the ordered states, such as their short-range, glassy nature and the spin incommensurability, are sample-independent. At the same time, some subtle features of the ordered phases, such as the correlation lengths, differ.