Microstructure of epitaxial strained BiCrO3 thin films

TL;DR

This study investigates the microstructure of epitaxial strained BiCrO3 thin films, revealing multiple coexisting phases due to local strain and oxygen distribution, which enhances understanding of Bi-based perovskites.

Contribution

It identifies a new phase in strained BiCrO3 films and explains the coexistence of multiple structural variants due to strain and oxygen inhomogeneity.

Findings

Three structural variants coexist in the films.

A new phase different from bulk phases is identified.

Local strain and oxygen distribution influence phase stabilization.

Abstract

The structure and microstrucutre of fully-strained BiCrO3 thin films have been investigated by X-rays diffraction and transmission electron microscopy, at room temperature. Interestingly, three structural variants are simultaneously stabilized within the film. While txo of them are consistent with the existing phases in the bulk-below and above the 420 K structural transition, a different phase is identified. The existence of various structures has been attributed to the inhomogeneous distribution of local strains and oxygens resulting from a minimization of the strain-energy at the interface. These findings will open the route to a better understanding of Bi-based perovskites and metastable phases.