Atomic-resolution TEM Studies of Pillar-Matrix Structures in Epitaxially Grown Ultrathin ZrO2-La2/3Sr1/3MnO3 Films

TL;DR

This study uses atomic-resolution TEM to analyze the structure and chemistry of ZrO2-La2/3Sr1/3MnO3 thin films, revealing atomic-level details of the pillar-matrix interface and elemental distributions affecting their magnetic and electronic properties.

Contribution

First atomic-resolution TEM analysis of ZrO2-La2/3Sr1/3MnO3 films, revealing detailed interface chemistry and elemental diffusion relevant to their properties.

Findings

Zr occupies Mn sites with less than 6 mol% solubility.

Zr concentration is lowest at the pillar-matrix interface with oxygen deficiency.

La and Mn diffuse into ZrO2 pillars and alter Mn valence state.

Abstract

We studied ZrO2-La2/3Sr1/3MnO3 pillar matrix thin films which were found to show anomalous magnetic and electron transport properties controlled by the amount of ZrO2. With the application of an aberration corrected transmission electron microscope, structure and chemical information of the system, especially of the pillar matrix interface were revealed at atomic resolution. Minor amounts of Zr were found to occupy Mn positions within the matrix and its solubility within the matrix was found to be less than 6 mol%. Moreover, the Zr concentration reached minimum concentration at the pillar matrix interface accompanied by oxygen deficiency. La and Mn diffusion into the pillar was observed along with a change of the Mn valence state. La and Mn positions inside ZrO2 pillars were also revealed at atomic resolution. These results provide detailed information for future studies of macroscopic properties of these materials.