Engineering the microstructure and magnetism of La$_2$CoMnO$_6$ thin films by tailoring oxygen stoichiometry

TL;DR

This study demonstrates how controlling oxygen stoichiometry during growth and annealing of La$_2$CoMnO$_6$ thin films influences their microstructure and magnetic properties, enabling tailored magnetic behavior.

Contribution

It provides a detailed analysis of the relationship between oxygen content, crystallographic orientation, and magnetic properties in La$_2$CoMnO$_6$ thin films, which was not previously established.

Findings

Oxygen stoichiometry affects Curie temperature and magnetic hysteresis.

Two crystallographic orientations are identified related to oxygen content.

In situ annealing can tailor microstructure and magnetic properties.

Abstract

We report on the magnetic and structural properties of ferromagnetic-insulating La$_2$CoMnO$_6$ thin films grown on top of (001) STO substrates by means of RF sputtering technique. Careful structural analysis, by using synchrotron X-ray diffraction, allows identifying two different crystallographic orientations that are closely related to oxygen stoichiometry and to the features (coercive fields and remanence) of the hysteresis loops. Both Curie temperature and magnetic hysteresis turn out to be dependent on the oxygen stoichiometry. In situ annealing conditions allow tailoring the oxygen content of the films, therefore controlling their microstructure and magnetic properties.